Hydrolock failure?
Thread Starter
Racer
Joined: May 2012
Posts: 427
Likes: 10
From: Texas
Hydrolock failure?
I’m looking for some input on an engine failure. This past February I did a heads, cam, intake injector swap on an 03 ls6 with 32,00 miles. After completing install I had my tuner install a base tune to get it up and going, I’d pulled the computer and taken to him and reinstalled. The heads are new TF and I cleaned the face on the block very well. I used Cometic Head gaskets and did have a little issue getting them over the alignment pins but upon removal didn’t see any damage on the gasket. All this to be said I fired the engine up and ran for several minutes one Saturday evening and while running the car had a very strong raw gas smell. I did a search and found info on large cam replacement and a poor tune can cause that so I assumed that was the cause for the raw gas smell. I left the car over night and came out the next morning to clean the car up and fired it up, as soon as I fired it up it went and was switched off directly. I called a friend who thought I may have dropped a nut etc in the intake at forts but then called back and said liquid which is what it ended up being. Like I’d said I didn’t see any indication when pulling the head off that the head gasket didn’t seal but I don’t know that you would be able. On the cylinder that went it did have a few small spots in the exhaust port that looked like they could be small blackened water spots? At first I thought water, then a leaky injector and now back to water. It’s irrelevant now but before firing up the new engine it would be nice to have a better understanding of what may have happened. One more time, very heavy raw gas while running and when reving lightly wasn’t crisp, like possible misfire.
Also so any idea how much liquid is needed to hydrolock an engine assuming stock specs?
thx Rich
Also so any idea how much liquid is needed to hydrolock an engine assuming stock specs?
thx Rich
Le Mans Master
Joined: Jul 2010
Posts: 5,987
Likes: 719
Man could be number of things, but what crosses my mine is stuck open injector. With the new cam that is larger your hitting the different values or different area on the tune the has different vacuum so it's going to hit different places on the air fuel table. Hope that makes sense. When I changed my cam and in I hector I didnt even change the tune. Ran rich in certain rpm areas . Ran for a few weeks like that until I got it to the tuner. Hope this helps
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
It only takes less than an oz of liquid. I had a coolant leak in my ported head and it filled the cylinder full of coolant. When I started the engine, the engine made about 1/1/2 revolutions and the #1 cylinder locked up and the starter busted off the block. After I had the head leak fixed and the starter boss welded back up, she ran hot straight and normal!!
TRY THIS:
Pop out the injector rail and flop it over backwards onto the windshield cowl. You can turn on the ignition and when the fuel system pressurizes, you will be able to see if an injector is leaking or stuck open.
TRY THIS:
Pop out the injector rail and flop it over backwards onto the windshield cowl. You can turn on the ignition and when the fuel system pressurizes, you will be able to see if an injector is leaking or stuck open.
Thread Starter
Racer
Joined: May 2012
Posts: 427
Likes: 10
From: Texas
The injectors where new, not to say one couldn’t have stuck. The injectors where the white fast 36# set. At this point it makes no difference, new motor as well as everything else. I’d really just like to have a better understanding of what may have caused it. Most likely will never really know ..
tgx
tgx
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maybe the wrong injector data entered in the tune or maybe just poor tuning period, see if you can find someone to pull the tune and look it over for anything super obvious
