thebrain

Vortec engine w/ 200K miles possible cracked head?

My 02 chevy express 1500 w/ 5.7 vortec has just over 200K miles the man that has been helping me lately w/ engines hasn’t really looked that close at it past connecting the tech2 tester up and finding mis fireing cylinders I think 2 and 4.

The problem was the disappearing antifreeze not on the driveway or though the waterpumps weep hole hence the occasional white smoke out the tailpipe.

This man basicalley says there is a cracked cylinder head guess he’s sean so many of the vortecs do this.

In hope it isn’t a cracked head I swapped in lower intake manifold gaskets that have been known to leak. Haven’t put it all back together yet. To see if I actually fixed something.

Anyway I have been informed that if I do a head swap on a engine w/ 200K miles the head will create to much compression and blowup the lower end, is this true or false?

Maybe a thicker head gasket?

I'm not a mechanic basicalley a bolton Guy Any suggestions on getting the express back on the road reliably and on budget is appreciated.
TB

CCrowell2

Sounds like intake gaskets have went bad, have done 3 on vortec 305/350s. Always lost coolant but not leaked and smelt like antifreeze at idle

someotherguy

Yeah how many of the older gen Vortecs has this guy worked on? They are notorious, literally, for intake gasket failure - on the original gaskets, anyway. Some that failed got replaced with the exact same plastic junk and of course failed again. There are updated gaskets from Fel-Pro that eliminate this weak link.

Re-reading your post that one paragraph is a little hard to follow. Sounded like someone else was working on it that said it was a cracked head - but you yourself replaced the intake gaskets? So you saw the gaskets, did they appear to have failed? Were they the original plastic junk?

Richard

thebrain

yes this Guy has worked on a bunch of vortecs maybe he doesn't smell any $ to be made.

so you Guy's think I could have actualley fixed the dissappearing antifreeze w/ mannie gasket swap. I drained a little oil and the antifreeze was in oil. heres a few images of under the mannie.

all I'm lacking is to figure out have to reinstall the distributer to test her out?

lastly for now will a compression test reveal cracked head?
thanks for advice

someotherguy

Ugh yes, those were the original plastic gaskets (or original type used to replace prior failed ones) - hopefully you didn't replace with same?

Full oil change is needed, any coolant in there will create an acidic condition with the oil and eat your bearings. Another change sooner than normal once you're up and running would be wise, too.

Those gaskets are ugly, so I'd say you found the issue. If it still continues to lose coolant then you could run a chemical block test to see if there are combustion gases in the cooling system.

The distributor has to be set using a scan tool that can read the cam retard angle. You want it within +/- 2 degrees of zero while holding RPM's to at least 1,000 for a good reading.

Richard