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'92 350 5.7 ltr- cracked block or head gasket?


relic000
06-06-2010, 02:03 PM
1992 chevy G20 conversion 5.7 ltr engine w/ 72000 miles- i lost my serpentine belt & didn't notice til temperature gauge was buried, pulled over and coolant is full of oil... none on the ground, just in the coolant. how do i figure out whether it's a cracked block or head gasket? is it even worth fixing without a new motor? thanks, w.

MT-2500
06-06-2010, 05:32 PM
1992 chevy G20 conversion 5.7 ltr engine w/ 72000 miles- i lost my serpentine belt & didn't notice til temperature gauge was buried, pulled over and coolant is full of oil... none on the ground, just in the coolant. how do i figure out whether it's a cracked block or head gasket? is it even worth fixing without a new motor? thanks, w.

All depends on how hot it got and if engine was in good shape before.

Coolant in oil can also be a blown in take gasket.

A chemical block test tester on coolant system will show cracked head or head gasket leakage if they are leaking exhaust into coolant.

relic000
06-06-2010, 10:10 PM
that did NOT answer my question- i said oil in the coolant, not coolant in the oil... a block tester will only find the presence of exhaust gasses- NOT which gasket is blown or if the block is cracked... w.

MT-2500
06-07-2010, 08:27 AM
that did NOT answer my question- i said oil in the coolant, not coolant in the oil... a block tester will only find the presence of exhaust gasses- NOT which gasket is blown or if the block is cracked... w.

Are you sure oil in coolant?
Does it have a engine oil cooler in radiator?
A lot of times old bad coolant can look like oil in it but not really oil.
Is you coolant just black/brown/oily or is it real milky?

DO NOT BE TO QUICK TO RULE OUT A BLOCK TEST.

A block tester should be used any time a engine has been hot like yours.
It can be used to find cracked heads and bad head gaskets and cracked blocks.
And in the hands of a good user it can even pinpoint which cylinder is bad.

relic000
06-07-2010, 09:05 AM
no coolant in the oil- only in coolant... yes there is an oil cooler, but i think it's for tranny fluid. coolant is like light chocolate milk. will it still show exhaust presence if it''s the intake gasket? already flushed entire cooling system.

MT-2500
06-07-2010, 09:48 AM
no coolant in the oil- only in coolant... yes there is an oil cooler, but i think it's for tranny fluid. coolant is like light chocolate milk. will it still show exhaust presence if it''s the intake gasket? already flushed entire cooling system.

No block test will not show intake leakage.

If you have flushed coolant system bypass transmission cooler jump across not block line and see what it does.

If it is transmission fluid in coolant the transmission usually gets coolant in it to.
That wipes out transmission fast.
May help and pay to flush/clean it out.

A good test to see if it is engine oil in coolant add some engine oil test dye to oil and see if it shows up in coolant.
Let us know how it goes.
Good Luck

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