924Board.org

[marky522]

I know I know this is a P-car board but this is very important and i know some of you have experience with 350's. My cousin recenlty got a 87 GMC (blazer) with a 350 with TBI, the motor was installed by a local used car dealer, and was only supposed to only have 5000 miles, the truck has a 10" skyjacker lift with 38" Super Swampers, He had it about a week and he only drove it two days out of the week due to the power steering breaking, then he fixed that and was driving it down the highway and it stalled and when he started it it was blowing white smoke everywhere, so he got it home and called the guy who sold it to him and told him it blew a headgasket and that they had said if he had any probs with it to just bring it back, so they refused to do anything, so today me and my cousin pulled the whole thing apart (i have never done a headgasket job before) so we got it just about pulled apart, we got the pass side head off, which is the side the smoke was coming from, and the #8 cyl was FULL of coolant, i just shrugged it off and went to clean it out and saw the #6 cyl, 1/8 of the piston was gone!!!
Now as i understand this, and correct me if i am wrong, this was caused by coolant entering the cylender and cooland not compressing like the air will??? And one other thing is it has dripped coolant ever since they got it, just a little, but i noticed that when i pulled the intake that the head wasnt exactly on the motor deck, just a small fine gap, anyway the guy said that he has never heard of water entering the cyl from a bad headgasket and breaking the piston, and blamed it on my cousin mudding it and water getting into the cyl and cousing it, but how would the water get in there? I need to tale to the guy tomorrow and i need to completely under stand this so i dont sound like an idiot. I truly appreciate any advice or info.

Thanks in advance,
Mark

[PORSCHEV]

Assuming your cousin never swapped the truck and brought water in the intake (Carb) it sounds like a water jacket colasped or something like that. Not knowing the historu of the engine is the what makes me wonder. It may made just had the gaskets changed and not properly torqued...do you recall how tight they were during disassembly?? Also did you take the other heasd off? If you did infact take water into the intake the other head would have water as well.

I would like to help more.. I would say your cousin is about to be screwed!!

[PORSCHEV]

Assuming your cousin never swapped the truck and brought water in the intake (Carb) it sounds like a water jacket colasped or something like that. Not knowing the historu of the engine is the what makes me wonder. It may made just had the gaskets changed and not properly torqued...do you recall how tight they were during disassembly?? Also did you take the other heasd off? If you did infact take water into the intake the other head would have water as well.

I would like to help more.. I would say your cousin is about to be screwed!!

[8trdrvr]

me and your cousin should go bowling together, we both got screwed.

water wont compress like air thats for sure. if air can pressurize the coolant side, if oil can go into the cyldrs id venture to say that coolant can get in there easy too if its bad enough.

sounds like ya'll have your weekend cut out for you

[JvGinPDX]

I managed to inhale water into my 1973 Volvo 145 when I plowed through a flooded intersection. While the water was not that deep, the momentum made a wave that got sucked into the intake. Bent the rods. You could also have rod problems. Since it seeped water from the beginning, it is safe to guess that the gasket was about to fail as well. Take the gasket to a mechanic for verification. It is sometimes possible to see some deformation in the gasket where the water leaked through. If enough water leaked through the gasket while the coolant was pressurized, it could flood a cylinder while the truck was parked for a while, like on a trip 7-11. On restarting, the water could then blow a hole in the piston.

[TinMan54]

Mark I ued to build Chevy 4 wheel drives for years if the haed was not saeted good on the block it is possible for water t oget into one or more of the cyl. Also if it was noy saeted good the head may have cracked. Most of the 350 heads tha tI have seen cracked have been at the water jackets .I hate to say it but I'll have to agree with the others he probably got screwed.

[friskynibbles]

your brother should sue him because he just got raped, big time.
my porsche had coolant residue in one cyinder when i got it and four cylinder was steamcleaned, but the pistons were all fine. it is possible that the temperature shock cracked that piston... i'm not an expert though. he should get a lawyer to write something up for him, take it to the dealership - basically a 'gimme back my money or i'll see you in court'.

[Richard]

Several things could have happened. Could have been bad headgasket or head mounting job, crack in waterjacket in block or in head. Was there any kind of warranty or was the truck sold as is? What are the laws about used cars where you live? Do some research. Your cousin is most likely screwed, and the engine needs a total teardown, as the rod is probably bent and maybe the crank. Block and head need to be pressure tested for leaks. May be cheaper to buy a short block if the current heads are ok. Most likely you can try to be nice and see if they will split the cost and later start ranting and raving and threating to sue if that doesn't work. He's scrwed, but anything is worth a try. Yes, the piston broke from hydraulic lock. Water does not compress

[larso]

While your engine is running, the cylinders are full of combustion. If the head gasket is leaky, or there is a crack in the head...and the engine is running, that will not cause enough water to cause hydraulic lock. It just seeps and drips in there and burns off right away. When water then starts filling up the cylinder when the engine is off, you have to start the car again. I don't think the starter motor is powerful enough to cause the piston to break, the engine will just not turn over. UNLESS chevy engines have really strong starter motors or something. If you however were moving while you turned the car off, and were in gear...the momentum of the engine would cause the piston to break or bend a rod etc. Did they coast into a parking lot, and turn the car off before they stopped or something? Or did they stall while driving on the highway? Or while idling?

The only other very weird possibility I can think of, if one of your valves was stuck closed..and you had a crack in the head before the valve, around the valve. Water collects above the valve, and then all of a sudden while driving the valve unsticks, and water gets dumped into the engine. That's a rare case that probably have too many odds of happening!...OR, is this an interference engine? Maybe it's a coincidence, the timing chain or belt broke while your headgasket also went, and the valve crushed the piston. Or you overheated the engine enough to cause enough detonation to destroy the piston. What kind of noises was the engine making while driving, was it sounding ok, and all of a sudden it just started blowing smoke, or did it actually make rocky noises as if something was going to break in the engine.

Or, the piston was broken before this all happened, and the car ran on 7 cylinders. What did the car run like, and did you check the oil before this all happened, such as when you were buying the car and you checked the dipstick to see the oil.

[marky522]

Thanks for all the great ansewers guys, THIS BOARD IS AWSOME!!!! Anywho, my cousin was driving down the highway and it stalled on him, no bang no ping just stalled, he started it back up and it fired right up, not really any power, and a lot of white smoke out the pass side tail pipe, he got it home and called the mech. The funny thing about the whole situation is that i was worried that we were fixing something that wasnt broken, cause i checked the dippstick and there wasnt any coolant present, and the oil smelled fine. the head is not cracked, i cant tell but like i said before i think the head is warped, when i looked at the rear of the head towards the intake the bottom of the head wasnt seated perfectly with the deck of the motor, like a small gap a litttle bigger than i would have expected, would a vehile run if say the number 8 cyl was getting coolant in it but was leaking out of the cyl onto the ground??? Cause there was a small leak at the back of the motor on that side, just a small drip of coolant??? When he got the truck the mech's told him to "bring it back if you have any probs son" and Tony doesnt want to own up to him mech's word, not to metion that the mech's are total morons, i have NEVER seen such crappy work,there were open vac lines, about 10 wires that werent connected to anything, just real crappy worksmanship. Again guys, this is the best web board out there i owe you guys big!!!!

Keep that advice comin, i dont meet with the guy till later!!!

MArk