Blown head gasket ?

[amani260]

Hi everyone, been a while since I have worked on the GMC.
Replaced heads , cam , lifters a while back then got sidetracked for a while before really testing it out. Anyway, it starts right up and runs little rough. I noticed bubbling in coolant with radiator cap off . Drained oil and it definitely has coolant in it. So Im trying to take my time before I just tear everything apart. Is there a way of determining , if it is a blown head gasket, which cylinder it is in without taking head off? Mainly meaning, if only one side is blown, why do both sides. I removed spark plugs but they all look same , didnt notice one looking cleaner or different color. Any thoughts would be appreciated, thanks

 

[Ricko1966]

Did it have coolant in the oil problems before the work? When did the problem start?

 

[amani260]

Well I dont think it was getting coolant in oil before I replaced heads and cam , but honestly its been quite a while since Ive worked on it, ( had some medical issues). I was secretly hoping it might be intake manifold leak instead of head gasket, just trying to pin it down before I go crazy replacing everything.

 

[amani260]

The bubbling in the radiator is what made me think head gasket

 

[Ricko1966]

Do a cooling system pressure test. If you don't have,don't want,can't afford a pressure tester,let me know. I do have a workaround. Anyway pressure test no spark plugs,dist hot lead disconnected,leave pressure on an hour or so,then crank the engine watch for water to shoot out of a plug hole.Yes cylinder head is coming off. No the drain the oil leave the plug out,wait for it to quit dripping,then wait some more. Okay,pressure test again,do you get a leak out of the drain plug?

 

[amani260]

I have a tester, somewhere. If I can find it I will give it a try, thank you

 

[amani260]

Ok, found the tester, ( my brother had it). Hooked it up, pumped up to 15 lbs, been sitting for about 3 hours, barely gone down a pound, thinking I need to wait til its gone down a good bit to get enough in cylinder to blow out . May give it overnight.

 

[Edelbrock]

If it lost 1 lb in 3 hours, I would say your probably OK. I mean, ambient temperature changes could cause a 1 pound drop, or maybe the seal on the tester is not 100% absolutely perfect.

Also, I would double check the intake manifold gaskets. Maybe re-torque it and see if any of the bolts are loose.

 

[Ricko1966]

Ok, found the tester, ( my brother had it). Hooked it up, pumped up to 15 lbs, been sitting for about 3 hours, barely gone down a pound, thinking I need to wait til its gone down a good bit to get enough in cylinder to blow out . May give it overnight.

Not a bad plan.

 

[amani260]

I know its getting into oil somewhere, might not be big leak , but Id like to figure out where, Im gettin too old to be climbing over into that engine bay more times than needed.

 

[Ricko1966]

If you have to wait 29.37 hours to verify it's leaking into a cylinder,but you verify the problem in 29.37 hours then you've done the right thing. There is no harm in doing it that way. I would say I would not wait until all pressure was gone though. I would be afraid of bleeding off all pressure and giving enough time for the cylinder to dry out. A last thought,are you sure the water in your oil is not leftover from when you pulled the manifold? Are you using the same manifold as before?

 

[amani260]

I dont think it is, but I cant swear to it, been a while since work was done.
I will check it in morning before work, see where its at. Thanks for responses

 

[amani260]

Ok, so I checked it few minutes ago, gone down about 3 1/2 lbs. Turned it iover few times, cant see anything coming out of spark plug holes. Did notice tiny leak at waterneck. So Im not sure where that puts me. I keep going back to the thing that originally got me thinking head gasket leak and that was bubbles in the radiator. Also , the fact there was coolant in oil when I drained it. I’ll keep investigating, thanks for responses

 

[Edelbrock]

This may or may not fit into your plan of attack, and many people think its a horrible product that will melt your mustache and turn your truck bumpers to mush - but I have seen it work wonders. Out of the last dozen or so applications that I have seen, it failed to solve the issue one time. The rest were fixed immediately and permanently. Unlike other products, it doesn't have any solid material in it, no grit or fibers to clog stuff up or to damage the water pump seal.

I generally use it / recommend it in situations where:

There is a leak that would be very expensive or difficult to repair.
The vehicle owner has a limited budget.
The vehicle is not worth spending a bunch of money on to fix.
The rig needs to be back on the road ASAP.

The two most recent repairs using this product:

2004 Chevy Impala. The head gasket was leaking fluid at the back of the engine. A drip of coolant running down the block. This stuff fixed it right away. The lady was low income and could not afford a major repair. I covered the cost of the Blue Devil for her, and she has had no problems with the car since. She is a happy camper.

1996 Isuzu Rodeo. There was a freeze plug on the back of the engine (hidden by the transmission, diagnosed by a different mechanic). Coolant was dripping out of the bottom of the bellhousing. They could not afford the repair, so they brought it to me and I suggested the Blue Devil. It sealed the leak right away, and they are very happy with the results.

Now if you like taking your engine apart, want 100% maximum reliability, don't mind spending the money or time etc, then you might as well fix it by the book. But chances are, if you put this in your rig it will be instantly fixed - and leaks in the future will be prevented as well.

I would not recommend it for a bad water pump seal because most of the time a bad seal can't be repaired this way, and because most water pumps are easy enough to replace - especially on older rigs.

 

[Sad Sack]

Can you tell us what type of heads were put on and intake / head gasket part numbers?