head gasket
Thread Starter
Racer
Joined: Sep 2021
Posts: 360
Likes: 59
head gasket
yesterday the battery died after trying to crank the engine. it did turn the engine but not enough to start. I did that a few times. Today I installed a new battery (a lithium 45Ah). (this can deliver higher amperage if needed, ) then I started the engine up and suddenly white steam came from the left bank exhaust manifold. I has rained recently and I thought maybe some water leaked onto the manifold, but then the. exhaust started making a lot of white steam. When I cranked it with the new battery the engine started immediately after the crankshaft barely rotated. my guess is the gasket was already weak and possibly extra fuel in the cylinders during previous cranking attempts possibly near hydrolock limit?! made it fail. Coolant level is now on cold level and 1” down, in the top tank, but will probably drop quickly. Not sure if I can drive like that to the repair shop where there will actually be an engine swap.
another cause I think can be an intake manifold leak, it’s been leaking to the outside a bit for a quite a while.
Any thoughts
thank you
PS I drove home and the smoke was gone, most likely rain water leaked into the exhaust.
another cause I think can be an intake manifold leak, it’s been leaking to the outside a bit for a quite a while.
Any thoughts
thank you
PS I drove home and the smoke was gone, most likely rain water leaked into the exhaust.
Last edited by Nilak; Apr 7, 2023 at 07:28 PM.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
Liquids don't compress. Hydraulic lock usually bends or breaks things. No smoke after driving,, oil that does not look like caramel,and not overheating usually indicates head gaskets are ok.
Thread Starter
Racer
Joined: Sep 2021
Posts: 360
Likes: 59
if the head chamber volume is say 58cc and you fill it with 57.5cc of gasoline it would increase the pressure to over 1200psi, (1200:1 plus temperature difference) anyway I don’t think it was that much gasoline in the cylinders. Injector are 22lbs /230ccpm but idk for startup they run say 10%, plus some gets spat out. I spent less than a minute cranking the car so most likely that didn’t do anything bad.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
If you hurt it you would know with a few miles. SBC Is pretty good at contaminating oil is a short time with a blown head gasket. There would be a loss of compression causing a roughness or miss while driving. It is possible to overfuel cylinders on engines that have weak batteries just grunting flywheel, all the energy is all going to the starter and injectors, there isn't enough voltag left to produce a strong spark. The new battery has no shortage of capacity so, as soon as spark reaches the overfueled cylinders; the engine immediately starts.
Thread Starter
Racer
Joined: Sep 2021
Posts: 360
Likes: 59
I got scared when I saw that white smoke and didn’t realise it could be water from the rain. The thing
is it rained for 4 days while the car was under a textile cover (enough to get through the fabric), then I drove it to work for 2 miles and then it sat for another day but it didn’t rain anymore so I can’t explain why water didn’t evaporated on the way to work. But I saw water on the exhaust flange. Oh, one possibility is it rained at work (2mi away) although it didn’t rained at home
And there were solar panels above the parking spots that make water drip worse than if you leave it under direct rain
I’ll go start it again in a couple of days and see what happens.
is it rained for 4 days while the car was under a textile cover (enough to get through the fabric), then I drove it to work for 2 miles and then it sat for another day but it didn’t rain anymore so I can’t explain why water didn’t evaporated on the way to work. But I saw water on the exhaust flange. Oh, one possibility is it rained at work (2mi away) although it didn’t rained at home
And there were solar panels above the parking spots that make water drip worse than if you leave it under direct rain I’ll go start it again in a couple of days and see what happens.
Last edited by Nilak; Apr 8, 2023 at 06:33 PM.
Thread Starter
Racer
Joined: Sep 2021
Posts: 360
Likes: 59
Unfortunately the rain water hypothesis was wrong. The steam in the exhaust was actually coolant and it’s been leaking into the exhaust. After driving a a few hundred yards I’ve noticed steam coming from exhaust and left bank and stopped the car. Then I wanted to start the engine back again and it hydrolocked. I didn’t realise it could leak into the cylinder. The leak is major and it filled the cylinder/s with coolant. It’s strange this seems correlated with the cranking attempts when the battery was too low. Now it’s clear, 100% head gasket failure.
PS I’ve pushed the car to get the water out and the engine starts but I won’t start it up again. The oil got quickly contaminated with coolant in those few hundred yards plus 1 minute of idling.
The car suffered from overheating lately and traces of oil in the coolant and this is an indication of an older problem, although the chemical gasket test had passed.
PS I’ve pushed the car to get the water out and the engine starts but I won’t start it up again. The oil got quickly contaminated with coolant in those few hundred yards plus 1 minute of idling.
The car suffered from overheating lately and traces of oil in the coolant and this is an indication of an older problem, although the chemical gasket test had passed.
Last edited by Nilak; Apr 10, 2023 at 03:56 PM.
Thread Starter
Racer
Joined: Sep 2021
Posts: 360
Likes: 59
I was thinking about removing all coolant then replacing the oil and start it up and leave it for like 30 s to lubricate the engine , because I have a new engine that I'll swap it for this one, but will take some time until they shop where I do this will be ready to do it. After that I can replace the gaskets and store the old engine as a backup. If I leave it like that for a month or who knows, the coolant would affect the internal components, even the contaminated coolant can start to do bad things in the coolant circuit
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Instructor
Joined: Mar 2021
Posts: 189
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From: Christiansburg Va
If it overheated bad enough to loose a head gasket, more than likely you will find the head has warped or cracked. You'll be more into it than installing some new gaskets if you plan to use it as a backup.
Thread Starter
Racer
Joined: Sep 2021
Posts: 360
Likes: 59
I’ve pulled some coolant and oil out. The coolant looks ok but on the bottom of the pan I’ve extracted 1l of coolant, the oil is light brown, there is still some oil left and already got over 8 liters from the pan.
I still wonder if the cranking attempts caused this. The injector add time vs battery voltage is about 7ms when voltage is around 4V. Probably best way is to stop trying if it doesn’t turn. I let the battery recover a for like 1 hour for a few times without charging, but never had power to turn the engine so fuel definitely buit up.