BLOWN Head gasket?

Az671

New Member
#1
I hooked up scan master and went for cruise around the block. I did two quick burst 20psi to watch readings on SM. I noticed on the way back it started to smoke under the hood. It looked water sprayed from reservoir to the exhaust and had some oil by the passenger wires too. It sounded weird and Temp got real hot 220. Later I noticed water dripping from passenger corner hood insulation. Is RJC HG the way to go?
 

rag231

Well-Known Member
#2
Are you sure that's a head gasket or just a broken / split coolant line some where? Pull out your dipstick and check your oil for chocolate milk. When I blew head gaskets my first indication was steam coming out of my turbo and filling up my block with coolant. My engine usually blew out inside the manifold towards the lifter area on cylinders 3 or 4.
 
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Az671

New Member
#3
Are you sure that's a head gasket or just a broken / split coolant line some where? Pull out your dipstick and check your oil for chocolate milk. When I blew head gaskets my first indication was steam coming out of my turbo and filling up my block with coolant. My engine usually blew out inside the manifold towards the lifter area on cylinders 3 or 4.
no water in oil but I need to check Radiator for oil.
 

3.8L V-8 eater

Well-Known Member
#5
I would use RJC head gasket or Cometic if your planning on running high boost...I had water spraying under the hood under boost...Started the car crawled underneath and had coolant seeping between the head gasket and the block...
 

Az671

New Member
#6
I would use RJC head gasket or Cometic if your planning on running high boost...I had water spraying under the hood under boost...Started the car crawled underneath and had coolant seeping between the head gasket and the block...
Ok, it sprayed toward the battery and turbo cover, but I can see oil on the spark plug wires below the breather.
 

rag231

Well-Known Member
#7
Did you hear any detonation or back fire when you were getting on it? I had the little "S" shaped coolant hose rub a hole thru because of the way the compressor housing on the turbo was clocked. The black pipe has a nipple that was sticking out too far with that hose connected to it. If you are running a front mount inter cooler the compressor is angled down around 45 degrees. Check that for coolant leaking. If it was your pax side breather leaking oil ( using stock valve covers), coolant could have sprayed from the "S" hose onto the breather.
 

getchasum

MISSING 2 CYLINDERS???
#9
GM Cadillac pills will clean up small seeps but shouldn’t be used to trying to seal a head gasket that’s given up...
 

Mr.Spool

Well-Known Member
#11
Is RJC HG the way to go?
you will be moving the potential damage into the piston area if things go wrong,the graphite gaskets will blow out before cracked pistons, cracked mains, torched deck and head,etc.usually;)at 20 psi the gasket is not holding you back.look into the tune and fuel pressure.
 

Az671

New Member
#12
Did you hear any detonation or back fire when you were getting on it? I had the little "S" shaped coolant hose rub a hole thru because of the way the compressor housing on the turbo was clocked. The black pipe has a nipple that was sticking out too far with that hose connected to it. If you are running a front mount inter cooler the compressor is angled down around 45 degrees. Check that for coolant leaking. If it was your pax side breather leaking oil ( using stock valve covers), coolant could have sprayed from the "S" hose onto the breather.
No knock or retard on timing. I got home and coolant leak. I'm going compression test it this weekend.
 

Az671

New Member
#13
you will be moving the potential damage into the piston area if things go wrong,the graphite gaskets will blow out before cracked pistons, cracked mains, torched deck and head,etc.usually;)at 20 psi the gasket is not holding you back.look into the tune and fuel pressure.
Yes, that is something I didn't consider. Valid point taken.
 
#17
Stock GM headgaskets for the reasons others stated above. Mine held 25-30psi of beatings for years and when one finally let go nothing else was damaged.
 

cruzn57

Still plays with cars!
#20
if your not using alcohol , your wasting your time, as it will just reoccur, over and over,
and if thats a stock fuel pump, .............well, ..............read the usual recipes for higher boost,
if your in AZ, go see Nick , he can and will advise you correctly.