Cooling problem

[james]

After some ideas about a stupid problem thats just started happening
in my car. Everything worked fine before, i just swapped the cam and
heads on my car last week and now i seem to be having a problem with
the cooling system.
It sits fine at its normal temperature, around 80deg. But then all of
a suddenly there will be like a water explosion noise and the temp
gauge (aftermarket mech one) will start shooting up very fast. The
water is exploding out of the overflow and i think you can hear it
boiling in the engine, now if i let it cool for half an hour and top
it up, usually around 500ml of water, it will then go back to its
normal temp as though nothing is wrong and be fine untill another
random time when it decided to do it again. It will go days without
doing it, but its a huge pain when it does happen.
What could be doing this? Ive tested the thermostat and done a basic
flush with the garden hose through the cooling system. Radiator cap
seems to be fine as well. No sign of oil in the water or vice versa.
Water isnt bubbling either with the motor running.
Could a headgasket cause this only at random times and not have any
other signs like steam out of the exhaust?
Thanks
Its a vc commodore 308, and im pretty sure i bleed the cooling system
right when i put the coolant in. Never had any trouble in the past.

[Clockmeister]

"james" <kaufman_j@hotmail.com> wrote in message
news:n3073117eb0gcsbi3hst4vflmu33q7oepj@4ax.com...
> After some ideas about a stupid problem thats just started happening
> in my car. Everything worked fine before, i just swapped the cam and
> heads on my car last week and now i seem to be having a problem with
> the cooling system.
> It sits fine at its normal temperature, around 80deg. But then all of
> a suddenly there will be like a water explosion noise and the temp
> gauge (aftermarket mech one) will start shooting up very fast. The
> water is exploding out of the overflow and i think you can hear it
> boiling in the engine, now if i let it cool for half an hour and top
> it up, usually around 500ml of water, it will then go back to its
> normal temp as though nothing is wrong and be fine untill another
> random time when it decided to do it again. It will go days without
> doing it, but its a huge pain when it does happen.
> What could be doing this? Ive tested the thermostat and done a basic
> flush with the garden hose through the cooling system. Radiator cap
> seems to be fine as well. No sign of oil in the water or vice versa.
> Water isnt bubbling either with the motor running.
> Could a headgasket cause this only at random times and not have any
> other signs like steam out of the exhaust?
> Thanks
> Its a vc commodore 308, and im pretty sure i bleed the cooling system
> right when i put the coolant in. Never had any trouble in the past.

Are the belts tight?

[Gonz]

>> After some ideas about a stupid problem thats just started happening
>> in my car. Everything worked fine before, i just swapped the cam and
>> heads on my car last week and now i seem to be having a problem with
>> the cooling system.
>> It sits fine at its normal temperature, around 80deg. But then all of
>> a suddenly there will be like a water explosion noise and the temp
>> gauge (aftermarket mech one) will start shooting up very fast. The
>> water is exploding out of the overflow and i think you can hear it
>> boiling in the engine, now if i let it cool for half an hour and top
>> it up, usually around 500ml of water, it will then go back to its
>> normal temp as though nothing is wrong and be fine untill another
>> random time when it decided to do it again. It will go days without
>> doing it, but its a huge pain when it does happen.
>> What could be doing this? Ive tested the thermostat and done a basic
>> flush with the garden hose through the cooling system. Radiator cap
>> seems to be fine as well. No sign of oil in the water or vice versa.
>> Water isnt bubbling either with the motor running.
>> Could a headgasket cause this only at random times and not have any
>> other signs like steam out of the exhaust?
>> Thanks
>> Its a vc commodore 308, and im pretty sure i bleed the cooling system
>> right when i put the coolant in. Never had any trouble in the past.
>
> Are the belts tight?

I were thinking Heads, are the water ports in the right place??

Are they the correct heads for the engine, what about the head gaskets, but
hey, I am not mechanicaly minded.
>
>
>

[james]

On Sun, 13 Mar 2005 11:13:13 +1100, "Gonz" <abuse@abuse.com> wrote:

>>> After some ideas about a stupid problem thats just started happening
>>> in my car. Everything worked fine before, i just swapped the cam and
>>> heads on my car last week and now i seem to be having a problem with
>>> the cooling system.
>>> It sits fine at its normal temperature, around 80deg. But then all of
>>> a suddenly there will be like a water explosion noise and the temp
>>> gauge (aftermarket mech one) will start shooting up very fast. The
>>> water is exploding out of the overflow and i think you can hear it
>>> boiling in the engine, now if i let it cool for half an hour and top
>>> it up, usually around 500ml of water, it will then go back to its
>>> normal temp as though nothing is wrong and be fine untill another
>>> random time when it decided to do it again. It will go days without
>>> doing it, but its a huge pain when it does happen.
>>> What could be doing this? Ive tested the thermostat and done a basic
>>> flush with the garden hose through the cooling system. Radiator cap
>>> seems to be fine as well. No sign of oil in the water or vice versa.
>>> Water isnt bubbling either with the motor running.
>>> Could a headgasket cause this only at random times and not have any
>>> other signs like steam out of the exhaust?
>>> Thanks
>>> Its a vc commodore 308, and im pretty sure i bleed the cooling system
>>> right when i put the coolant in. Never had any trouble in the past.
>>
>> Are the belts tight?
>
>I were thinking Heads, are the water ports in the right place??
>
>Are they the correct heads for the engine, what about the head gaskets, but
>hey, I am not mechanicaly minded.
>>
Yeah correct heads, had them on for a couple years. I only took them
off to be reconditioned.

[John_H]

james wrote:

>After some ideas about a stupid problem thats just started happening
>in my car. Everything worked fine before, i just swapped the cam and
>heads on my car last week and now i seem to be having a problem with
>the cooling system.
<snip>
>Its a vc commodore 308, and im pretty sure i bleed the cooling system
>right when i put the coolant in. Never had any trouble in the past.

Heads are a likely possibility -- either a leaking gasket or a leaking
valve seat insert. The latter is a common problem in 308's, which
have very little metal around the valve seats for machining....

Were the replacement heads inserted immediately prior to fitting?...
If so it's the first area I'd check (assuming you actually measured
the amount of coolant that went back in -- which is easy to recheck).

--
John H

[John Mackesy]

james wrote:
>
> It sits fine at its normal temperature, around 80deg. But then all of
> a suddenly there will be like a water explosion noise and the temp
> gauge (aftermarket mech one) will start shooting up very fast. The
> water is exploding out of the overflow and i think you can hear it
> boiling in the engine, now if i let it cool for half an hour and top
> it up, usually around 500ml of water, it will then go back to its
> normal temp as though nothing is wrong and be fine untill another
> random time when it decided to do it again.

<snippage>

I had a '79 Gemini (from new, not my choice) that did this. Cured by
replacing the thermostat with a vented type (Morris 1100, actually). The
theory is that water is not the greatest conductor of heat and unless
the water is moving past the thermostat it doesn't get the message.
After a while the temp and pressure gets up in the engine and lifts the
radiator pressure cap. About a 3mm hole drilled in the thermostat works.

John Mackesy

[Clockmeister]

"james" <kaufman_j@hotmail.com> wrote in message
news:qn17319pi5jmoupccg40bs6j8u1u7bllto@4ax.com...
> On Sun, 13 Mar 2005 07:56:40 +0800, "Clockmeister"
> <no-one@nowhere.com> wrote:
>
> >
> >"james" <kaufman_j@hotmail.com> wrote in message
> >news:n3073117eb0gcsbi3hst4vflmu33q7oepj@4ax.com...
> >> After some ideas about a stupid problem thats just started happening
> >> in my car. Everything worked fine before, i just swapped the cam and
> >> heads on my car last week and now i seem to be having a problem with
> >> the cooling system.
> >> It sits fine at its normal temperature, around 80deg. But then all of
> >> a suddenly there will be like a water explosion noise and the temp
> >> gauge (aftermarket mech one) will start shooting up very fast. The
> >> water is exploding out of the overflow and i think you can hear it
> >> boiling in the engine, now if i let it cool for half an hour and top
> >> it up, usually around 500ml of water, it will then go back to its
> >> normal temp as though nothing is wrong and be fine untill another
> >> random time when it decided to do it again. It will go days without
> >> doing it, but its a huge pain when it does happen.
> >> What could be doing this? Ive tested the thermostat and done a basic
> >> flush with the garden hose through the cooling system. Radiator cap
> >> seems to be fine as well. No sign of oil in the water or vice versa.
> >> Water isnt bubbling either with the motor running.
> >> Could a headgasket cause this only at random times and not have any
> >> other signs like steam out of the exhaust?
> >> Thanks
> >> Its a vc commodore 308, and im pretty sure i bleed the cooling system
> >> right when i put the coolant in. Never had any trouble in the past.
> >
> >Are the belts tight?
> >
> >
> i'll double check it. Is it possible for the belt to be slipping
> without making the terrible belt slipping noise?

I've seen it happen, particularly if the fan belt is very loose. Easy to
check.

[Albm&ctd]

In article <n3073117eb0gcsbi3hst4vflmu33q7oepj@4ax.com>,
kaufman_j@hotmail.com says...
> After some ideas about a stupid problem thats just started happening
> in my car. Everything worked fine before, i just swapped the cam and
> heads on my car last week and now i seem to be having a problem with
> the cooling system.
> It sits fine at its normal temperature, around 80deg. But then all of
> a suddenly there will be like a water explosion noise and the temp
> gauge (aftermarket mech one) will start shooting up very fast. The
> water is exploding out of the overflow and i think you can hear it
> boiling in the engine, now if i let it cool for half an hour and top
> it up, usually around 500ml of water, it will then go back to its
> normal temp as though nothing is wrong and be fine untill another
> random time when it decided to do it again. It will go days without
> doing it, but its a huge pain when it does happen.
> What could be doing this? Ive tested the thermostat and done a basic
> flush with the garden hose through the cooling system. Radiator cap
> seems to be fine as well. No sign of oil in the water or vice versa.
> Water isnt bubbling either with the motor running.
> Could a headgasket cause this only at random times and not have any
> other signs like steam out of the exhaust?
> Thanks
> Its a vc commodore 308, and im pretty sure i bleed the cooling system
> right when i put the coolant in. Never had any trouble in the past.
>
Is there a possibility of the valley gaskets incorectly installed
blocking water passages? It's about 20 years ago when I first came across
something similar with a Holden V8. A quick read of what you wrote made
me think, maybe the same problem.

Al
--
I don't take sides.
It's more fun to insult everyone.
http://kwakakid.cjb.net/insult.html

[Graham W]

> james wrote:
>> It sits fine at its normal temperature, around 80deg. But then all of
>> a suddenly there will be like a water explosion noise and the temp
>> gauge (aftermarket mech one) will start shooting up very fast. The
>> water is exploding out of the overflow and i think you can hear it
>> boiling in the engine, now if i let it cool for half an hour and top
>> it up, usually around 500ml of water, it will then go back to its
>> normal temp as though nothing is wrong and be fine untill another
>> random time when it decided to do it again.

John Mackesy wrote:
> <snippage>
> I had a '79 Gemini (from new, not my choice) that did this. Cured by
> replacing the thermostat with a vented type (Morris 1100, actually). The
> theory is that water is not the greatest conductor of heat and unless
> the water is moving past the thermostat it doesn't get the message.
> After a while the temp and pressure gets up in the engine and lifts the
> radiator pressure cap. About a 3mm hole drilled in the thermostat works.
>
> John Mackesy


I'm with John on this one.

When the thermostat is fully closed, no water flows past it to warm it
enough to open. Unless enough heat conducts through the water itself or
the block, it doesn't open.

The "explosion" is the thermostat finally opening and releasing water
into a part of the motor where the temperature has already exceeded
boiling point. Once the thermostat opens, it has a continuous flow of
warm water over it so it never fully closes until the motor is stone
cold again.

In a Mini this is a well known problem, because *some* Minis have a
bypass hose to prevent it happening, and other Minis have a bleed hole
in the thermostat instead. Put the wrong thermostat in and the car
overheats yet the thermostat never opens.

The solution in a Mini is to drill a 3mm or 1/8" hole through the
thermostat plate to let a small amount of water past it when it's
closed. I would expect the same approach to work for you, and it's
simple, quick and cheap to try before you go looking for more
complicated problems like an incorrectly fitted head gasket!

[Clockmeister]

"Graham W" <zebedee@alphalink.commercial.au> wrote in message
news:39ijsfF63bff3U1@individual.net...
> > james wrote:
> >> It sits fine at its normal temperature, around 80deg. But then all of
> >> a suddenly there will be like a water explosion noise and the temp
> >> gauge (aftermarket mech one) will start shooting up very fast. The
> >> water is exploding out of the overflow and i think you can hear it
> >> boiling in the engine, now if i let it cool for half an hour and top
> >> it up, usually around 500ml of water, it will then go back to its
> >> normal temp as though nothing is wrong and be fine untill another
> >> random time when it decided to do it again.
>
> John Mackesy wrote:
> > <snippage>
> > I had a '79 Gemini (from new, not my choice) that did this. Cured by
> > replacing the thermostat with a vented type (Morris 1100, actually). The
> > theory is that water is not the greatest conductor of heat and unless
> > the water is moving past the thermostat it doesn't get the message.
> > After a while the temp and pressure gets up in the engine and lifts the
> > radiator pressure cap. About a 3mm hole drilled in the thermostat works.
> >
> > John Mackesy
>
>
> I'm with John on this one.
>
> When the thermostat is fully closed, no water flows past it to warm it
> enough to open. Unless enough heat conducts through the water itself or
> the block, it doesn't open.
>
> The "explosion" is the thermostat finally opening and releasing water
> into a part of the motor where the temperature has already exceeded
> boiling point. Once the thermostat opens, it has a continuous flow of
> warm water over it so it never fully closes until the motor is stone
> cold again.
>
> In a Mini this is a well known problem, because *some* Minis have a
> bypass hose to prevent it happening, and other Minis have a bleed hole
> in the thermostat instead. Put the wrong thermostat in and the car
> overheats yet the thermostat never opens.
>
> The solution in a Mini is to drill a 3mm or 1/8" hole through the
> thermostat plate to let a small amount of water past it when it's
> closed. I would expect the same approach to work for you, and it's
> simple, quick and cheap to try before you go looking for more
> complicated problems like an incorrectly fitted head gasket!

I've heard about this problem, but I haven't seen a thermostat without the
bleeder hole in 10 years. Still, I would replace it before I go pulling head
off too, it could be sticking or have some other problem.

[Clockmeister]

"Graham W" <zebedee@alphalink.commercial.au> wrote in message
news:39k2nsF62irmnU1@individual.net...
> John_H wrote:
> > Or, for those of us who don't cost our time by the minute, remove and
> > test it in a saucepan of water on the stove -- hang it by a piece of
> > string so you can remove and replace it to make it open and close.
>
> The problem we're talking about is not that the thermostat is faulty and
> won't open in warm water. It is that without some form of bypass, the
> thermostat doesn't get enough warm water to open it until the rest of
> the motor is far too hot. Once it opens, everything works fine.

I know, but those thermostats without the bypass I haven't seen for at least
10 years.

[John_H]

Clockmeister wrote:

>
>"Graham W" <zebedee@alphalink.commercial.au> wrote in message
>news:39k2nsF62irmnU1@individual.net...
>> John_H wrote:
>> > Or, for those of us who don't cost our time by the minute, remove and
>> > test it in a saucepan of water on the stove -- hang it by a piece of
>> > string so you can remove and replace it to make it open and close.
>>
>> The problem we're talking about is not that the thermostat is faulty and
>> won't open in warm water. It is that without some form of bypass, the
>> thermostat doesn't get enough warm water to open it until the rest of
>> the motor is far too hot. Once it opens, everything works fine.
>
>I know, but those thermostats without the bypass I haven't seen for at least
>10 years.

Me neither. :)

--
John H

[james]

On Sun, 13 Mar 2005 11:37:09 +1100, John Mackesy <mack@melbpc.org.au>
wrote:

>james wrote:
>>
>> It sits fine at its normal temperature, around 80deg. But then all of
>> a suddenly there will be like a water explosion noise and the temp
>> gauge (aftermarket mech one) will start shooting up very fast. The
>> water is exploding out of the overflow and i think you can hear it
>> boiling in the engine, now if i let it cool for half an hour and top
>> it up, usually around 500ml of water, it will then go back to its
>> normal temp as though nothing is wrong and be fine untill another
>> random time when it decided to do it again.
>
><snippage>
>
>I had a '79 Gemini (from new, not my choice) that did this. Cured by
>replacing the thermostat with a vented type (Morris 1100, actually). The
>theory is that water is not the greatest conductor of heat and unless
>the water is moving past the thermostat it doesn't get the message.
>After a while the temp and pressure gets up in the engine and lifts the
>radiator pressure cap. About a 3mm hole drilled in the thermostat works.
>
>John Mackesy

Ive just replaced the radiator cap and it didnt solve the problem. So
i just bought a new thermostat and drilled the hole in it, the old
one already had it but the new one didnt have the hole. Anyway i havnt
driven it yet but some things i noticed while bleeding it, at idle
speed, around 1000rpm it all seems normal, but when idling at 1500 the
water, instead of burping the bubbles out well it errupts like a
volcano. Probabley around 5-8cm's in the air. Can lots of air in the
system do this or is it most likely a head gasket problem. I dont
know if i should wait it out and see if the errupting stops because
its sending the temp gauge all over the place above normal temp,
around 90-100deg C . Water wasnt boiling though. It blows out a fair
bit of water while its doing this. So could this be normal and i just
need to hope it will stop and get rid of any air or would symptoms
like this be more likely a head gasket leak or similar?

[atec]

james wrote:
> On Sun, 13 Mar 2005 11:37:09 +1100, John Mackesy <mack@melbpc.org.au>
> wrote:
>
>
>>james wrote:
>>
>>>It sits fine at its normal temperature, around 80deg. But then all of
>>>a suddenly there will be like a water explosion noise and the temp
>>>gauge (aftermarket mech one) will start shooting up very fast. The
>>>water is exploding out of the overflow and i think you can hear it
>>>boiling in the engine, now if i let it cool for half an hour and top
>>>it up, usually around 500ml of water, it will then go back to its
>>>normal temp as though nothing is wrong and be fine untill another
>>>random time when it decided to do it again.
>>
>><snippage>
>>
>>I had a '79 Gemini (from new, not my choice) that did this. Cured by
>>replacing the thermostat with a vented type (Morris 1100, actually). The
>>theory is that water is not the greatest conductor of heat and unless
>>the water is moving past the thermostat it doesn't get the message.
>>After a while the temp and pressure gets up in the engine and lifts the
>>radiator pressure cap. About a 3mm hole drilled in the thermostat works.
>>
>>John Mackesy
>
>
> Ive just replaced the radiator cap and it didnt solve the problem. So
> i just bought a new thermostat and drilled the hole in it, the old
> one already had it but the new one didnt have the hole. Anyway i havnt
> driven it yet but some things i noticed while bleeding it, at idle
> speed, around 1000rpm it all seems normal, but when idling at 1500 the
> water, instead of burping the bubbles out well it errupts like a
> volcano. Probabley around 5-8cm's in the air. Can lots of air in the
> system do this or is it most likely a head gasket problem. I dont
> know if i should wait it out and see if the errupting stops because
> its sending the temp gauge all over the place above normal temp,
> around 90-100deg C . Water wasnt boiling though. It blows out a fair
> bit of water while its doing this. So could this be normal and i just
> need to hope it will stop and get rid of any air or would symptoms
> like this be more likely a head gasket leak or similar?
>
>
tighten the cap and see what happens watching the gauge closly

[james]

On Wed, 16 Mar 2005 15:20:27 +1000, atec <"atec77(atec)"@hotmail.com>
wrote:

>james wrote:
>> On Sun, 13 Mar 2005 11:37:09 +1100, John Mackesy <mack@melbpc.org.au>
>> wrote:
>>
>>
>>>james wrote:
>>>
>>>>It sits fine at its normal temperature, around 80deg. But then all of
>>>>a suddenly there will be like a water explosion noise and the temp
>>>>gauge (aftermarket mech one) will start shooting up very fast. The
>>>>water is exploding out of the overflow and i think you can hear it
>>>>boiling in the engine, now if i let it cool for half an hour and top
>>>>it up, usually around 500ml of water, it will then go back to its
>>>>normal temp as though nothing is wrong and be fine untill another
>>>>random time when it decided to do it again.
>>>
>>><snippage>
>>>
>>>I had a '79 Gemini (from new, not my choice) that did this. Cured by
>>>replacing the thermostat with a vented type (Morris 1100, actually). The
>>>theory is that water is not the greatest conductor of heat and unless
>>>the water is moving past the thermostat it doesn't get the message.
>>>After a while the temp and pressure gets up in the engine and lifts the
>>>radiator pressure cap. About a 3mm hole drilled in the thermostat works.
>>>
>>>John Mackesy
>>
>>
>> Ive just replaced the radiator cap and it didnt solve the problem. So
>> i just bought a new thermostat and drilled the hole in it, the old
>> one already had it but the new one didnt have the hole. Anyway i havnt
>> driven it yet but some things i noticed while bleeding it, at idle
>> speed, around 1000rpm it all seems normal, but when idling at 1500 the
>> water, instead of burping the bubbles out well it errupts like a
>> volcano. Probabley around 5-8cm's in the air. Can lots of air in the
>> system do this or is it most likely a head gasket problem. I dont
>> know if i should wait it out and see if the errupting stops because
>> its sending the temp gauge all over the place above normal temp,
>> around 90-100deg C . Water wasnt boiling though. It blows out a fair
>> bit of water while its doing this. So could this be normal and i just
>> need to hope it will stop and get rid of any air or would symptoms
>> like this be more likely a head gasket leak or similar?
>>
>>
>tighten the cap and see what happens watching the gauge closly

Ok, all seems normal with the cap on. Temp is sitting fine at its
normal 80deg temp. Its not moving a budge. I havnt taken it for a
test drive yet, problem is the temp does stay fine untill it decides
to spit the dummy. Something i noticed yesterday, but it was with the
old thermostat so it may not do it with the new one but it may mean
something so ill mention it anyway: The car was running fine all day
untill the afternoon when it spat it, thing was before the temp gauge
started rising there was a knocking noise first, so that had me
panicked because i thought it was the engine. When the noise started
i looked down and a couple seconds later the temp gauge is going up (
well jumping back and faward going up. Turned the motor off and
coasted to a park and opened the engine bay. It was like someone
inside the thermostat housing was hitting it with a hammer, 2 hits a
second or so. It eventually stopped. The temp was now reading just
over 100. I started the engine back up hoping it would cool it and
sure enough the temp drop like a rock down to 70 and rose back to 80
and stayed there like it should. It did it again on the way back to
my place, knock knock and the temp gauge going wild, being in a bad
mood by now i kept driving, when the gauge would get to 100 i would
give the engine a big rev and it would drop again, holding the revs up
didnt keep the temp down though, just the occasional rev up.
Sorry for writing a novel here, hopefully it may lead to some clues
as to whats going on.
The water didnt sound like it was boiling, i wasnt game enough to
undo the radiator cap to look though.

[John_H]

james wrote:

>
>So could this be normal and i just
>need to hope it will stop and get rid of any air or would symptoms
>like this be more likely a head gasket leak or similar?

Once again... have valve seat inserts been fitted recently?

Syptoms sound close to what I'd expect to happen with a loose insert
where its recess has breached a water jacket.

--
John H

[james]

On Wed, 16 Mar 2005 16:26:15 +1000, John_H <john4271@hotmail.com>
wrote:

>james wrote:
>
>>
>>So could this be normal and i just
>>need to hope it will stop and get rid of any air or would symptoms
>>like this be more likely a head gasket leak or similar?
>
>Once again... have valve seat inserts been fitted recently?
>
>Syptoms sound close to what I'd expect to happen with a loose insert
>where its recess has breached a water jacket.

Im pretty sure it doesnt have inserts, its one of those things i wish
i had gotten now but was too stingy at the time to pay the extra 200
bucks they wanted.
Ill be pissed if hes broken through into the water jacket, he was
doing some porting, just pocket porting as far as i know.

[John Hudson]

"james" <kaufman_j@hotmail.com> wrote in message
news:55df3198dsjoutrhvlgi1lnj39ecipoe2d@4ax.com...
> On Sun, 13 Mar 2005 11:37:09 +1100, John Mackesy <mack@melbpc.org.au>
> wrote:
>
when idling at 1500 the
> water, instead of burping the bubbles out well it errupts like a
> volcano. Probabley around 5-8cm's in the air. would symptoms
> like this be more likely a head gasket leak or similar?

Try doing a compression test on each cylinder with all the spark plugs
removed and the radiator cap off. See if and when water spurts out....

huddo
>
>