just to clarify, i didn't polish the head, i polished the block. i
never touched the head after it was machined.

small update:
i drove the car to work today which ends up being about 70 miles round
trip. at the end of my trip home (which is about a 2500 foot climb
into some mountains), i park the car, turn off the motor and i hear
silence for a time. which if i haven't been clear, is sort of normal
but sometimes i would have a little bubbling after parking and turning
off the motor.

it was clear though that this time there was no bubbling, even after a
hard drive. however, after about 10 or 15 seconds i start hearing the
slurping of the coolant past the rad cap. then the bubbling started.
so, *no* bubbling with engine running, and *bubbling* shortly after the
enginie is shut off.

i pulled the overflow tube out of the resevoir and noticed coolant
coming out in small quantities in time with the slurping sound. is it
possible that the recently shut down engine heats up slightly (i think
they do after shut down), thereby heating up coolant in the engine,
pushing coolant past the rad cap, but the flow is momentary (the
slurping) creating a small steam pocket in the overflow tube, which
then is manifested as bubbles in the overflow resevoir?

the rad cap is newish (~6 months old), but i have at least two other
ones that i may test to see if they perform differently.

i am now hopeful that the engine is okay since bubbling isn't ocurring
during engine operation.

thanks so much for all your input.

josh

jim beam wrote:
> Jim Yanik wrote:
> > larson.joshua@gmail.com wrote in
> > news:1150430858.954298.27930@h76g2000cwa.googlegro ups.com:
> >
> >
> >>>>i cleaned and lapped the surface of the block.
> >>>
> >>>how exactly did you do this?
> >>
> >>i scraped the block surface with a plastic scraper at first. then i
> >>used carb cleaner and a toothbrush to scrub off the remaining gasket
> >>crud. after it was fairly clean i used 600 grit sandpaper tightly
> >>stapled to an index card sized piece of flat particle board. i lightly
> >>sanded the surface.
> >
> >
> > You did this before or AFTER the head was machined to flatten it?
> > Why would old gasket material need to be removed after machining to flatten
> > it? It should not BE there after machining. Besides,I believe you do NOT
> > want the mating surfaces to be polished(there's no need for it) because it
> > would reduce sealing to the gasket.
> >
> >
> >>the head surface seemed near perfect after being machined. there were
> >>no scrapes/scratches of much significance on the block that i could
> >>tell, but who knows. what do you mean by "impossible for a gas seal to
> >>be made?"
> >
> >
> >
> > The head would not clamp down on the GASKET sufficiently if polished or
> > polishing affected the levelness recreated by the machining.
> >
> sealing is much more effective with a /smooth/ surface. look at the
> mating surfaces on high pressure valves and artillery. you're right if
> "polishing" makes the surface deviate from completely flat, but the
> flatter & smoother the better.

 

jim beam <nospam@example.net> wrote in
news:ZomdnTqYbeA3zg7ZnZ2dnUVZ_vWdnZ2d@speakeasy.ne t:

> Jim Yanik wrote:
>> larson.joshua@gmail.com wrote in
>> news:1150430858.954298.27930@h76g2000cwa.googlegro ups.com:
>>
>>
>>>>>i cleaned and lapped the surface of the block.
>>>>
>>>>how exactly did you do this?
>>>
>>>i scraped the block surface with a plastic scraper at first. then i
>>>used carb cleaner and a toothbrush to scrub off the remaining gasket
>>>crud. after it was fairly clean i used 600 grit sandpaper tightly
>>>stapled to an index card sized piece of flat particle board. i
>>>lightly sanded the surface.
>>
>>
>> You did this before or AFTER the head was machined to flatten it?
>> Why would old gasket material need to be removed after machining to
>> flatten it? It should not BE there after machining. Besides,I believe
>> you do NOT want the mating surfaces to be polished(there's no need
>> for it) because it would reduce sealing to the gasket.
>>
>>
>>>the head surface seemed near perfect after being machined. there
>>>were no scrapes/scratches of much significance on the block that i
>>>could tell, but who knows. what do you mean by "impossible for a gas
>>>seal to be made?"
>>
>>
>>
>> The head would not clamp down on the GASKET sufficiently if polished
>> or polishing affected the levelness recreated by the machining.
>>
> sealing is much more effective with a /smooth/ surface.

Not when you're compressing a head gasket,not all the time.
With a metallic gasket,you WANT a texture to grip the gasket.
*The gasket is what does the sealing.*


> look at the
> mating surfaces on high pressure valves and artillery.

Which do not use gaskets. They are -mating- surfaces.

> you're right
> if "polishing" makes the surface deviate from completely flat, but the
> flatter & smoother the better.
>



--
Jim Yanik
jyanik
at
kua.net

 

jim beam <nospam@example.net> wrote in
news:ZomdnTqYbeA3zg7ZnZ2dnUVZ_vWdnZ2d@speakeasy.ne t:

> Jim Yanik wrote:
>> larson.joshua@gmail.com wrote in
>> news:1150430858.954298.27930@h76g2000cwa.googlegro ups.com:
>>
>>
>>>>>i cleaned and lapped the surface of the block.
>>>>
>>>>how exactly did you do this?
>>>
>>>i scraped the block surface with a plastic scraper at first. then i
>>>used carb cleaner and a toothbrush to scrub off the remaining gasket
>>>crud. after it was fairly clean i used 600 grit sandpaper tightly
>>>stapled to an index card sized piece of flat particle board. i
>>>lightly sanded the surface.
>>
>>
>> You did this before or AFTER the head was machined to flatten it?
>> Why would old gasket material need to be removed after machining to
>> flatten it? It should not BE there after machining. Besides,I believe
>> you do NOT want the mating surfaces to be polished(there's no need
>> for it) because it would reduce sealing to the gasket.
>>
>>
>>>the head surface seemed near perfect after being machined. there
>>>were no scrapes/scratches of much significance on the block that i
>>>could tell, but who knows. what do you mean by "impossible for a gas
>>>seal to be made?"
>>
>>
>>
>> The head would not clamp down on the GASKET sufficiently if polished
>> or polishing affected the levelness recreated by the machining.
>>
> sealing is much more effective with a /smooth/ surface.

Not when you're compressing a head gasket,not all the time.
With a metallic gasket,you WANT a texture to grip the gasket.
*The gasket is what does the sealing.*


> look at the
> mating surfaces on high pressure valves and artillery.

Which do not use gaskets. They are -mating- surfaces.

> you're right
> if "polishing" makes the surface deviate from completely flat, but the
> flatter & smoother the better.
>



--
Jim Yanik
jyanik
at
kua.net

 

jim beam <nospam@example.net> wrote in
news:ZomdnTqYbeA3zg7ZnZ2dnUVZ_vWdnZ2d@speakeasy.ne t:

> Jim Yanik wrote:
>> larson.joshua@gmail.com wrote in
>> news:1150430858.954298.27930@h76g2000cwa.googlegro ups.com:
>>
>>
>>>>>i cleaned and lapped the surface of the block.
>>>>
>>>>how exactly did you do this?
>>>
>>>i scraped the block surface with a plastic scraper at first. then i
>>>used carb cleaner and a toothbrush to scrub off the remaining gasket
>>>crud. after it was fairly clean i used 600 grit sandpaper tightly
>>>stapled to an index card sized piece of flat particle board. i
>>>lightly sanded the surface.
>>
>>
>> You did this before or AFTER the head was machined to flatten it?
>> Why would old gasket material need to be removed after machining to
>> flatten it? It should not BE there after machining. Besides,I believe
>> you do NOT want the mating surfaces to be polished(there's no need
>> for it) because it would reduce sealing to the gasket.
>>
>>
>>>the head surface seemed near perfect after being machined. there
>>>were no scrapes/scratches of much significance on the block that i
>>>could tell, but who knows. what do you mean by "impossible for a gas
>>>seal to be made?"
>>
>>
>>
>> The head would not clamp down on the GASKET sufficiently if polished
>> or polishing affected the levelness recreated by the machining.
>>
> sealing is much more effective with a /smooth/ surface.

Not when you're compressing a head gasket,not all the time.
With a metallic gasket,you WANT a texture to grip the gasket.
*The gasket is what does the sealing.*


> look at the
> mating surfaces on high pressure valves and artillery.

Which do not use gaskets. They are -mating- surfaces.

> you're right
> if "polishing" makes the surface deviate from completely flat, but the
> flatter & smoother the better.
>



--
Jim Yanik
jyanik
at
kua.net

 

larson.joshua@gmail.com wrote:
> just to clarify, i didn't polish the head, i polished the block. i
> never touched the head after it was machined.
>
> small update:
> i drove the car to work today which ends up being about 70 miles round
> trip. at the end of my trip home (which is about a 2500 foot climb
> into some mountains), i park the car, turn off the motor and i hear
> silence for a time. which if i haven't been clear, is sort of normal
> but sometimes i would have a little bubbling after parking and turning
> off the motor.
>
> it was clear though that this time there was no bubbling, even after a
> hard drive. however, after about 10 or 15 seconds i start hearing the
> slurping of the coolant past the rad cap. then the bubbling started.
> so, *no* bubbling with engine running, and *bubbling* shortly after the
> enginie is shut off.
>
> i pulled the overflow tube out of the resevoir and noticed coolant
> coming out in small quantities in time with the slurping sound. is it
> possible that the recently shut down engine heats up slightly (i think
> they do after shut down), thereby heating up coolant in the engine,
> pushing coolant past the rad cap, but the flow is momentary (the
> slurping) creating a small steam pocket in the overflow tube, which
> then is manifested as bubbles in the overflow resevoir?

there's only one situation where bubbling in the expansion reservoir is
"ok", and that's the first time after the coolant's been refilled.
that's the "burp". after that, all the air in the system should be
expelled as it rises to the top of the rad and expands out as the system
warms up. [it won't do it if there's too much air in the system, but
i'm assuming everything was refilled ok.]

if the gasket/head/motor is still leaking, what you'll then find is that
excess fluid gets pushed out to the expansion reservoir, and it stays
there as the motor cools overnight. if there's an air gap under the
radiator cap in the morning, it's either a radiator/hose leak, /or/ its
gas from an engine leak having over-filled the system.

at this stage, you have to leave it to do its thing undisturbed
overnight after it's been running to full temp. if you want to spend a
little more money, there's a hydrocarbon test you can do on the coolant
to see if exhaust is leaking into it, but i'm not sure how much that is
offhand.

>
> the rad cap is newish (~6 months old), but i have at least two other
> ones that i may test to see if they perform differently.
>
> i am now hopeful that the engine is okay since bubbling isn't ocurring
> during engine operation.

i have my fingers crossed for you. i've just been through all this
myself, and mine wouldn't bubble while i watched it. gunning it up a
big multi-mile hill at 105 degrees sure did the job though. it would
blow coolant, then not suck back to refill completely. having changed
/all/ the hoses and the rad and the water pump, there was only one other
thing, the gasket. and as if to confirm, the last time i looked under
the hood just before performing surgery, sure enough, there was a steady
stream on bubbles blowing into the expansion reservoir.

good luck.

>
> thanks so much for all your input.
>
> josh
>
> jim beam wrote:
>
>>Jim Yanik wrote:
>>
>>>larson.joshua@gmail.com wrote in
>>>news:1150430858.954298.27930@h76g2000cwa.google groups.com:
>>>
>>>
>>>
>>>>>>i cleaned and lapped the surface of the block.
>>>>>
>>>>>how exactly did you do this?
>>>>
>>>>i scraped the block surface with a plastic scraper at first. then i
>>>>used carb cleaner and a toothbrush to scrub off the remaining gasket
>>>>crud. after it was fairly clean i used 600 grit sandpaper tightly
>>>>stapled to an index card sized piece of flat particle board. i lightly
>>>>sanded the surface.
>>>
>>>
>>>You did this before or AFTER the head was machined to flatten it?
>>>Why would old gasket material need to be removed after machining to flatten
>>>it? It should not BE there after machining. Besides,I believe you do NOT
>>>want the mating surfaces to be polished(there's no need for it) because it
>>>would reduce sealing to the gasket.
>>>
>>>
>>>
>>>>the head surface seemed near perfect after being machined. there were
>>>>no scrapes/scratches of much significance on the block that i could
>>>>tell, but who knows. what do you mean by "impossible for a gas seal to
>>>>be made?"
>>>
>>>
>>>
>>>The head would not clamp down on the GASKET sufficiently if polished or
>>>polishing affected the levelness recreated by the machining.
>>>
>>
>>sealing is much more effective with a /smooth/ surface. look at the
>>mating surfaces on high pressure valves and artillery. you're right if
>>"polishing" makes the surface deviate from completely flat, but the
>>flatter & smoother the better.
>
>

 

larson.joshua@gmail.com wrote:
> just to clarify, i didn't polish the head, i polished the block. i
> never touched the head after it was machined.
>
> small update:
> i drove the car to work today which ends up being about 70 miles round
> trip. at the end of my trip home (which is about a 2500 foot climb
> into some mountains), i park the car, turn off the motor and i hear
> silence for a time. which if i haven't been clear, is sort of normal
> but sometimes i would have a little bubbling after parking and turning
> off the motor.
>
> it was clear though that this time there was no bubbling, even after a
> hard drive. however, after about 10 or 15 seconds i start hearing the
> slurping of the coolant past the rad cap. then the bubbling started.
> so, *no* bubbling with engine running, and *bubbling* shortly after the
> enginie is shut off.
>
> i pulled the overflow tube out of the resevoir and noticed coolant
> coming out in small quantities in time with the slurping sound. is it
> possible that the recently shut down engine heats up slightly (i think
> they do after shut down), thereby heating up coolant in the engine,
> pushing coolant past the rad cap, but the flow is momentary (the
> slurping) creating a small steam pocket in the overflow tube, which
> then is manifested as bubbles in the overflow resevoir?

there's only one situation where bubbling in the expansion reservoir is
"ok", and that's the first time after the coolant's been refilled.
that's the "burp". after that, all the air in the system should be
expelled as it rises to the top of the rad and expands out as the system
warms up. [it won't do it if there's too much air in the system, but
i'm assuming everything was refilled ok.]

if the gasket/head/motor is still leaking, what you'll then find is that
excess fluid gets pushed out to the expansion reservoir, and it stays
there as the motor cools overnight. if there's an air gap under the
radiator cap in the morning, it's either a radiator/hose leak, /or/ its
gas from an engine leak having over-filled the system.

at this stage, you have to leave it to do its thing undisturbed
overnight after it's been running to full temp. if you want to spend a
little more money, there's a hydrocarbon test you can do on the coolant
to see if exhaust is leaking into it, but i'm not sure how much that is
offhand.

>
> the rad cap is newish (~6 months old), but i have at least two other
> ones that i may test to see if they perform differently.
>
> i am now hopeful that the engine is okay since bubbling isn't ocurring
> during engine operation.

i have my fingers crossed for you. i've just been through all this
myself, and mine wouldn't bubble while i watched it. gunning it up a
big multi-mile hill at 105 degrees sure did the job though. it would
blow coolant, then not suck back to refill completely. having changed
/all/ the hoses and the rad and the water pump, there was only one other
thing, the gasket. and as if to confirm, the last time i looked under
the hood just before performing surgery, sure enough, there was a steady
stream on bubbles blowing into the expansion reservoir.

good luck.

>
> thanks so much for all your input.
>
> josh
>
> jim beam wrote:
>
>>Jim Yanik wrote:
>>
>>>larson.joshua@gmail.com wrote in
>>>news:1150430858.954298.27930@h76g2000cwa.google groups.com:
>>>
>>>
>>>
>>>>>>i cleaned and lapped the surface of the block.
>>>>>
>>>>>how exactly did you do this?
>>>>
>>>>i scraped the block surface with a plastic scraper at first. then i
>>>>used carb cleaner and a toothbrush to scrub off the remaining gasket
>>>>crud. after it was fairly clean i used 600 grit sandpaper tightly
>>>>stapled to an index card sized piece of flat particle board. i lightly
>>>>sanded the surface.
>>>
>>>
>>>You did this before or AFTER the head was machined to flatten it?
>>>Why would old gasket material need to be removed after machining to flatten
>>>it? It should not BE there after machining. Besides,I believe you do NOT
>>>want the mating surfaces to be polished(there's no need for it) because it
>>>would reduce sealing to the gasket.
>>>
>>>
>>>
>>>>the head surface seemed near perfect after being machined. there were
>>>>no scrapes/scratches of much significance on the block that i could
>>>>tell, but who knows. what do you mean by "impossible for a gas seal to
>>>>be made?"
>>>
>>>
>>>
>>>The head would not clamp down on the GASKET sufficiently if polished or
>>>polishing affected the levelness recreated by the machining.
>>>
>>
>>sealing is much more effective with a /smooth/ surface. look at the
>>mating surfaces on high pressure valves and artillery. you're right if
>>"polishing" makes the surface deviate from completely flat, but the
>>flatter & smoother the better.
>
>

 

larson.joshua@gmail.com wrote:
> just to clarify, i didn't polish the head, i polished the block. i
> never touched the head after it was machined.
>
> small update:
> i drove the car to work today which ends up being about 70 miles round
> trip. at the end of my trip home (which is about a 2500 foot climb
> into some mountains), i park the car, turn off the motor and i hear
> silence for a time. which if i haven't been clear, is sort of normal
> but sometimes i would have a little bubbling after parking and turning
> off the motor.
>
> it was clear though that this time there was no bubbling, even after a
> hard drive. however, after about 10 or 15 seconds i start hearing the
> slurping of the coolant past the rad cap. then the bubbling started.
> so, *no* bubbling with engine running, and *bubbling* shortly after the
> enginie is shut off.
>
> i pulled the overflow tube out of the resevoir and noticed coolant
> coming out in small quantities in time with the slurping sound. is it
> possible that the recently shut down engine heats up slightly (i think
> they do after shut down), thereby heating up coolant in the engine,
> pushing coolant past the rad cap, but the flow is momentary (the
> slurping) creating a small steam pocket in the overflow tube, which
> then is manifested as bubbles in the overflow resevoir?

there's only one situation where bubbling in the expansion reservoir is
"ok", and that's the first time after the coolant's been refilled.
that's the "burp". after that, all the air in the system should be
expelled as it rises to the top of the rad and expands out as the system
warms up. [it won't do it if there's too much air in the system, but
i'm assuming everything was refilled ok.]

if the gasket/head/motor is still leaking, what you'll then find is that
excess fluid gets pushed out to the expansion reservoir, and it stays
there as the motor cools overnight. if there's an air gap under the
radiator cap in the morning, it's either a radiator/hose leak, /or/ its
gas from an engine leak having over-filled the system.

at this stage, you have to leave it to do its thing undisturbed
overnight after it's been running to full temp. if you want to spend a
little more money, there's a hydrocarbon test you can do on the coolant
to see if exhaust is leaking into it, but i'm not sure how much that is
offhand.

>
> the rad cap is newish (~6 months old), but i have at least two other
> ones that i may test to see if they perform differently.
>
> i am now hopeful that the engine is okay since bubbling isn't ocurring
> during engine operation.

i have my fingers crossed for you. i've just been through all this
myself, and mine wouldn't bubble while i watched it. gunning it up a
big multi-mile hill at 105 degrees sure did the job though. it would
blow coolant, then not suck back to refill completely. having changed
/all/ the hoses and the rad and the water pump, there was only one other
thing, the gasket. and as if to confirm, the last time i looked under
the hood just before performing surgery, sure enough, there was a steady
stream on bubbles blowing into the expansion reservoir.

good luck.

>
> thanks so much for all your input.
>
> josh
>
> jim beam wrote:
>
>>Jim Yanik wrote:
>>
>>>larson.joshua@gmail.com wrote in
>>>news:1150430858.954298.27930@h76g2000cwa.google groups.com:
>>>
>>>
>>>
>>>>>>i cleaned and lapped the surface of the block.
>>>>>
>>>>>how exactly did you do this?
>>>>
>>>>i scraped the block surface with a plastic scraper at first. then i
>>>>used carb cleaner and a toothbrush to scrub off the remaining gasket
>>>>crud. after it was fairly clean i used 600 grit sandpaper tightly
>>>>stapled to an index card sized piece of flat particle board. i lightly
>>>>sanded the surface.
>>>
>>>
>>>You did this before or AFTER the head was machined to flatten it?
>>>Why would old gasket material need to be removed after machining to flatten
>>>it? It should not BE there after machining. Besides,I believe you do NOT
>>>want the mating surfaces to be polished(there's no need for it) because it
>>>would reduce sealing to the gasket.
>>>
>>>
>>>
>>>>the head surface seemed near perfect after being machined. there were
>>>>no scrapes/scratches of much significance on the block that i could
>>>>tell, but who knows. what do you mean by "impossible for a gas seal to
>>>>be made?"
>>>
>>>
>>>
>>>The head would not clamp down on the GASKET sufficiently if polished or
>>>polishing affected the levelness recreated by the machining.
>>>
>>
>>sealing is much more effective with a /smooth/ surface. look at the
>>mating surfaces on high pressure valves and artillery. you're right if
>>"polishing" makes the surface deviate from completely flat, but the
>>flatter & smoother the better.
>
>

 

Jim Yanik wrote:
> jim beam <nospam@example.net> wrote in
> news:ZomdnTqYbeA3zg7ZnZ2dnUVZ_vWdnZ2d@speakeasy.ne t:
>
>
>>Jim Yanik wrote:
>>
>>>larson.joshua@gmail.com wrote in
>>>news:1150430858.954298.27930@h76g2000cwa.google groups.com:
>>>
>>>
>>>
>>>>>>i cleaned and lapped the surface of the block.
>>>>>
>>>>>how exactly did you do this?
>>>>
>>>>i scraped the block surface with a plastic scraper at first. then i
>>>>used carb cleaner and a toothbrush to scrub off the remaining gasket
>>>>crud. after it was fairly clean i used 600 grit sandpaper tightly
>>>>stapled to an index card sized piece of flat particle board. i
>>>>lightly sanded the surface.
>>>
>>>
>>>You did this before or AFTER the head was machined to flatten it?
>>>Why would old gasket material need to be removed after machining to
>>>flatten it? It should not BE there after machining. Besides,I believe
>>>you do NOT want the mating surfaces to be polished(there's no need
>>>for it) because it would reduce sealing to the gasket.
>>>
>>>
>>>
>>>>the head surface seemed near perfect after being machined. there
>>>>were no scrapes/scratches of much significance on the block that i
>>>>could tell, but who knows. what do you mean by "impossible for a gas
>>>>seal to be made?"
>>>
>>>
>>>
>>>The head would not clamp down on the GASKET sufficiently if polished
>>>or polishing affected the levelness recreated by the machining.
>>>
>>
>>sealing is much more effective with a /smooth/ surface.
>
>
> Not when you're compressing a head gasket,not all the time.
> With a metallic gasket,you WANT a texture to grip the gasket.

with respect, you're stuck in detroit there jim. "grip" on a gasket is
simply grooving along which gas can escape - you really don't want it.
that's why your old ford blew gaskets every 60k and a honda [typically]
will go hundreds without being touched. i promise you, oem spec honda
heads are near mirror finish, and that's for good reason.

> *The gasket is what does the sealing.*
>
>
>
>>look at the
>>mating surfaces on high pressure valves and artillery.
>
>
> Which do not use gaskets.

they'd use them if they could! gaskets are single/low-cycle use.

> They are -mating- surfaces.

there's /two/ mating surfaces when a gasket is used, e.g., block to
gasket, gasket to head. /both/ need to seal, not just one.

>
>
>>you're right
>>if "polishing" makes the surface deviate from completely flat, but the
>>flatter & smoother the better.
>>
>
>
>
>

 

Jim Yanik wrote:
> jim beam <nospam@example.net> wrote in
> news:ZomdnTqYbeA3zg7ZnZ2dnUVZ_vWdnZ2d@speakeasy.ne t:
>
>
>>Jim Yanik wrote:
>>
>>>larson.joshua@gmail.com wrote in
>>>news:1150430858.954298.27930@h76g2000cwa.google groups.com:
>>>
>>>
>>>
>>>>>>i cleaned and lapped the surface of the block.
>>>>>
>>>>>how exactly did you do this?
>>>>
>>>>i scraped the block surface with a plastic scraper at first. then i
>>>>used carb cleaner and a toothbrush to scrub off the remaining gasket
>>>>crud. after it was fairly clean i used 600 grit sandpaper tightly
>>>>stapled to an index card sized piece of flat particle board. i
>>>>lightly sanded the surface.
>>>
>>>
>>>You did this before or AFTER the head was machined to flatten it?
>>>Why would old gasket material need to be removed after machining to
>>>flatten it? It should not BE there after machining. Besides,I believe
>>>you do NOT want the mating surfaces to be polished(there's no need
>>>for it) because it would reduce sealing to the gasket.
>>>
>>>
>>>
>>>>the head surface seemed near perfect after being machined. there
>>>>were no scrapes/scratches of much significance on the block that i
>>>>could tell, but who knows. what do you mean by "impossible for a gas
>>>>seal to be made?"
>>>
>>>
>>>
>>>The head would not clamp down on the GASKET sufficiently if polished
>>>or polishing affected the levelness recreated by the machining.
>>>
>>
>>sealing is much more effective with a /smooth/ surface.
>
>
> Not when you're compressing a head gasket,not all the time.
> With a metallic gasket,you WANT a texture to grip the gasket.

with respect, you're stuck in detroit there jim. "grip" on a gasket is
simply grooving along which gas can escape - you really don't want it.
that's why your old ford blew gaskets every 60k and a honda [typically]
will go hundreds without being touched. i promise you, oem spec honda
heads are near mirror finish, and that's for good reason.

> *The gasket is what does the sealing.*
>
>
>
>>look at the
>>mating surfaces on high pressure valves and artillery.
>
>
> Which do not use gaskets.

they'd use them if they could! gaskets are single/low-cycle use.

> They are -mating- surfaces.

there's /two/ mating surfaces when a gasket is used, e.g., block to
gasket, gasket to head. /both/ need to seal, not just one.

>
>
>>you're right
>>if "polishing" makes the surface deviate from completely flat, but the
>>flatter & smoother the better.
>>
>
>
>
>

 

Jim Yanik wrote:
> jim beam <nospam@example.net> wrote in
> news:ZomdnTqYbeA3zg7ZnZ2dnUVZ_vWdnZ2d@speakeasy.ne t:
>
>
>>Jim Yanik wrote:
>>
>>>larson.joshua@gmail.com wrote in
>>>news:1150430858.954298.27930@h76g2000cwa.google groups.com:
>>>
>>>
>>>
>>>>>>i cleaned and lapped the surface of the block.
>>>>>
>>>>>how exactly did you do this?
>>>>
>>>>i scraped the block surface with a plastic scraper at first. then i
>>>>used carb cleaner and a toothbrush to scrub off the remaining gasket
>>>>crud. after it was fairly clean i used 600 grit sandpaper tightly
>>>>stapled to an index card sized piece of flat particle board. i
>>>>lightly sanded the surface.
>>>
>>>
>>>You did this before or AFTER the head was machined to flatten it?
>>>Why would old gasket material need to be removed after machining to
>>>flatten it? It should not BE there after machining. Besides,I believe
>>>you do NOT want the mating surfaces to be polished(there's no need
>>>for it) because it would reduce sealing to the gasket.
>>>
>>>
>>>
>>>>the head surface seemed near perfect after being machined. there
>>>>were no scrapes/scratches of much significance on the block that i
>>>>could tell, but who knows. what do you mean by "impossible for a gas
>>>>seal to be made?"
>>>
>>>
>>>
>>>The head would not clamp down on the GASKET sufficiently if polished
>>>or polishing affected the levelness recreated by the machining.
>>>
>>
>>sealing is much more effective with a /smooth/ surface.
>
>
> Not when you're compressing a head gasket,not all the time.
> With a metallic gasket,you WANT a texture to grip the gasket.

with respect, you're stuck in detroit there jim. "grip" on a gasket is
simply grooving along which gas can escape - you really don't want it.
that's why your old ford blew gaskets every 60k and a honda [typically]
will go hundreds without being touched. i promise you, oem spec honda
heads are near mirror finish, and that's for good reason.

> *The gasket is what does the sealing.*
>
>
>
>>look at the
>>mating surfaces on high pressure valves and artillery.
>
>
> Which do not use gaskets.

they'd use them if they could! gaskets are single/low-cycle use.

> They are -mating- surfaces.

there's /two/ mating surfaces when a gasket is used, e.g., block to
gasket, gasket to head. /both/ need to seal, not just one.

>
>
>>you're right
>>if "polishing" makes the surface deviate from completely flat, but the
>>flatter & smoother the better.
>>
>
>
>
>

 

larson.joshua@gmail.com wrote:
>
> just to clarify, i didn't polish the head, i polished the block. i
> never touched the head after it was machined.
>
> small update:
> i drove the car to work today which ends up being about 70 miles round
> trip. at the end of my trip home (which is about a 2500 foot climb
> into some mountains), i park the car, turn off the motor and i hear
> silence for a time. which if i haven't been clear, is sort of normal
> but sometimes i would have a little bubbling after parking and turning
> off the motor.
>
> it was clear though that this time there was no bubbling, even after a
> hard drive. however, after about 10 or 15 seconds i start hearing the
> slurping of the coolant past the rad cap. then the bubbling started.
> so, *no* bubbling with engine running, and *bubbling* shortly after the
> enginie is shut off.
>
> i pulled the overflow tube out of the resevoir and noticed coolant
> coming out in small quantities in time with the slurping sound. is it
> possible that the recently shut down engine heats up slightly (i think
> they do after shut down), thereby heating up coolant in the engine,
> pushing coolant past the rad cap, but the flow is momentary (the
> slurping) creating a small steam pocket in the overflow tube, which
> then is manifested as bubbles in the overflow resevoir?
>
> the rad cap is newish (~6 months old), but i have at least two other
> ones that i may test to see if they perform differently.
>
> i am now hopeful that the engine is okay since bubbling isn't ocurring
> during engine operation.
>
> thanks so much for all your input.
>
> josh

--------------------------------

Here's another tip: You can't really overfill the reservoir with
coolant. Any air the system displaces will just bubble out since it's
not a sealed (pressurized) reservoir. Check it every morning when the
system is stone cold. Make sure it's at MAX. Check it next morning,
refill to MAX. Once ALL the air is out it will stop 'sipping' from the
reservoir. That will tell you how 'healthy' the cooling system is.

'Curly'

 

larson.joshua@gmail.com wrote:
>
> just to clarify, i didn't polish the head, i polished the block. i
> never touched the head after it was machined.
>
> small update:
> i drove the car to work today which ends up being about 70 miles round
> trip. at the end of my trip home (which is about a 2500 foot climb
> into some mountains), i park the car, turn off the motor and i hear
> silence for a time. which if i haven't been clear, is sort of normal
> but sometimes i would have a little bubbling after parking and turning
> off the motor.
>
> it was clear though that this time there was no bubbling, even after a
> hard drive. however, after about 10 or 15 seconds i start hearing the
> slurping of the coolant past the rad cap. then the bubbling started.
> so, *no* bubbling with engine running, and *bubbling* shortly after the
> enginie is shut off.
>
> i pulled the overflow tube out of the resevoir and noticed coolant
> coming out in small quantities in time with the slurping sound. is it
> possible that the recently shut down engine heats up slightly (i think
> they do after shut down), thereby heating up coolant in the engine,
> pushing coolant past the rad cap, but the flow is momentary (the
> slurping) creating a small steam pocket in the overflow tube, which
> then is manifested as bubbles in the overflow resevoir?
>
> the rad cap is newish (~6 months old), but i have at least two other
> ones that i may test to see if they perform differently.
>
> i am now hopeful that the engine is okay since bubbling isn't ocurring
> during engine operation.
>
> thanks so much for all your input.
>
> josh

--------------------------------

Here's another tip: You can't really overfill the reservoir with
coolant. Any air the system displaces will just bubble out since it's
not a sealed (pressurized) reservoir. Check it every morning when the
system is stone cold. Make sure it's at MAX. Check it next morning,
refill to MAX. Once ALL the air is out it will stop 'sipping' from the
reservoir. That will tell you how 'healthy' the cooling system is.

'Curly'

 

larson.joshua@gmail.com wrote:
>
> just to clarify, i didn't polish the head, i polished the block. i
> never touched the head after it was machined.
>
> small update:
> i drove the car to work today which ends up being about 70 miles round
> trip. at the end of my trip home (which is about a 2500 foot climb
> into some mountains), i park the car, turn off the motor and i hear
> silence for a time. which if i haven't been clear, is sort of normal
> but sometimes i would have a little bubbling after parking and turning
> off the motor.
>
> it was clear though that this time there was no bubbling, even after a
> hard drive. however, after about 10 or 15 seconds i start hearing the
> slurping of the coolant past the rad cap. then the bubbling started.
> so, *no* bubbling with engine running, and *bubbling* shortly after the
> enginie is shut off.
>
> i pulled the overflow tube out of the resevoir and noticed coolant
> coming out in small quantities in time with the slurping sound. is it
> possible that the recently shut down engine heats up slightly (i think
> they do after shut down), thereby heating up coolant in the engine,
> pushing coolant past the rad cap, but the flow is momentary (the
> slurping) creating a small steam pocket in the overflow tube, which
> then is manifested as bubbles in the overflow resevoir?
>
> the rad cap is newish (~6 months old), but i have at least two other
> ones that i may test to see if they perform differently.
>
> i am now hopeful that the engine is okay since bubbling isn't ocurring
> during engine operation.
>
> thanks so much for all your input.
>
> josh

--------------------------------

Here's another tip: You can't really overfill the reservoir with
coolant. Any air the system displaces will just bubble out since it's
not a sealed (pressurized) reservoir. Check it every morning when the
system is stone cold. Make sure it's at MAX. Check it next morning,
refill to MAX. Once ALL the air is out it will stop 'sipping' from the
reservoir. That will tell you how 'healthy' the cooling system is.

'Curly'

 

I'm solidly with the "smooth surface" view on this, but the question as it
relates to this thread is whether the head gasket is leaking or not. I
suspect not, but the OP really needs to check it out.

Mike

 

I'm solidly with the "smooth surface" view on this, but the question as it
relates to this thread is whether the head gasket is leaking or not. I
suspect not, but the OP really needs to check it out.

Mike