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engine help


bro9178
06-25-2009, 06:50 PM
:runaround:
Hi eveyone, I have a 1998 Chevy Tahoe 4X4. I have just finished replacing the cyl. heads because they were cracked. Now I hear a "clacking" sound coming from the bottom of the engine when the engine starts to warm up, and a sreaching sound when accelerated. I have also noticed that the oil has a fuel like smell to it, and has a different consistency. When the problems first appeared the oil pressure gauge dropped to almost 0 psi.

Any advise to help diagnose is appreciated.

toddman67
06-25-2009, 08:01 PM
Did you change the oil and filter afterthe extensive work? If not, the oil is more than likely contaminated with the other fluids for the repair. Don't run it anymore until you do another oil and filter service.
The squeel is probably comming from the belt that might be contaminated now as well. Clean things down with shop solvent and see if the noise disappears. If not remove the belt and temporarily run the engine to see if the noise goes away.

maxwedge
06-25-2009, 08:28 PM
Good advice, but why would anyone run an engine with fuel contaminated oil, hope you didn't spin a bearing!!

bro9178
06-25-2009, 10:40 PM
The oil and filter were replaced after the extensive work. I have not used the truck since the first time I noticed the noise. I heard that it could be the fuel regulator, how possible can that be?

toddman67
06-25-2009, 11:06 PM
These days anything is possible. Get a fuel pressure tester, check the pressure running and disconnect the regulator to see if there is a change in pressure.

j cAT
06-26-2009, 12:12 AM
:runaround:
Hi eveyone, I have a 1998 Chevy Tahoe 4X4. I have just finished replacing the cyl. heads because they were cracked. Now I hear a "clacking" sound coming from the bottom of the engine when the engine starts to warm up, and a sreaching sound when accelerated. I have also noticed that the oil has a fuel like smell to it, and has a different consistency. When the problems first appeared the oil pressure gauge dropped to almost 0 psi.

Any advise to help diagnose is appreciated.

this may be coolant got into the engine oil,,,when the head had cracked..if you ran engine for a period of time with this condition usually the engine should be replaced..I suspect the main crank bearings are bad...

bro9178
06-27-2009, 11:54 PM
Ok, all fingers a pointing to the main bearings. How hard would it be to replace them, at the amatuer level. I have spoken to several people, and they say it could be that. When the heads were cracked, I ran the truck like that for some time. Is it recommened to change the piston rings as well? I changed the engine oil once again and I don't have the "fuel" like smell anymore. When changing the oil I found alot of metal shavings on the tip of the oil plug.

toddman67
06-28-2009, 09:31 AM
A good way to tell, is to do a compression test on each cylinder. If they all test good, then the next step would be to drop the oil pan and pull a couple of rod and main bearing caps. look for scorn crank. If thats the case, then the crank needs to be re-ground. If the crank looks okay, then you might get away with new bearnings. The crankshaft should look smooth as glass.

j cAT
06-28-2009, 12:03 PM
Ok, all fingers a pointing to the main bearings. How hard would it be to replace them, at the amatuer level. I have spoken to several people, and they say it could be that. When the heads were cracked, I ran the truck like that for some time. Is it recommened to change the piston rings as well? I changed the engine oil once again and I don't have the "fuel" like smell anymore. When changing the oil I found alot of metal shavings on the tip of the oil plug.

It is your money////you want to repair a totalled motor with this damage is not correct.../smart ...

If you have limited funds get a scrap yard replacement if not then get a loan and get a rebuilt/new motor with a warrantee..

running the engine with coolant engine leaks destroys the O2 sensors these must be replaced as well,,,possibly the cat converters also..

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