I have a lq4 swap with dart pro 1 heads EPS cam whipple supercharger and other small things. I just installed the heads and the leak began. It is a massive leak. We cleanex everything thought it was the valve cover but its not. After cleaning everything you can literally watch the small 10mm head bolt at the back of the intake start to seap oil when the truck is running. We tried removing them one at a time and adding sealer and no help. Please help

 

Is it the small head bolt at the top of the head or the intake bolt ? If its at the back maybe the blocks cracked into the oil passage going to the sensor. Does the whipple have oil pressure to it? The only way oil is fed to the heads is through the push rods. That's why I'm thinking there's a crack. maybe there was fluid in the hole when you assembled it and it hydraulic cracked into to oil pass.

 

Its definately the head bolt. You can watch it as the oil comes up. How does that work to crack the head like you said? I have done quite a bit of work on cars but never heard that. The block has 2000 miles so I really hope thats not it. But if it is is there any crazy fix for that. Thank you for the reply.

 

Hydraulic pressure caused by water/coolant sitting at the bottom of the bolt hole (usually from pulling the original head off). When you tighten up the bolt the water/coolant doesnt have anywhere to go. Its pretty well documented in the LS world to clean out the bolts holes thoroughly before installing the bolts. Some use compressed air, others use rolled up paper towels etc...

Sorry man, afraid theres not an easy fix for this one.

Mike

 

So what next? Pull the block and flux it? or will it be more visually obvious than that? Damn, what a bummer! Let us know what ya find man.... Interested.

 

I've only seen one crack in the mentioned area and it went about 6" into the block.

If you've never heard about it then nobody ever took the time to tell you. ANY bolt holt on these engines is susceptible to fluid entrapment and subsquent block fracture from putting a bolt on top and torquing. You will know when you do it because you'll get to the torque point and suddenly the bolt is a whole lot easier to turn.

 

Well this could be a crap deal then. I guess ill have to tear it apart and figure this out. Would the oil be likely to move elsewhere also. I know it will take the path of least resistance. I guess ill tear it back apart next week. Its a long shot but maybe becauae its only a 22lb. Torque bolt it dixnt do too much damage if thats it. Thats just me praying though lol. Thank you guys. Ill let you knw what I find.

 

What side of the block is it leaking on??? Driver side or pass side???

Where did you get the heads from???

 

It s leaking from both sides. We have come up with excessive crank case pressure due to a set of valve covers that I got off of the mptor with the heads. And the person took out the internal baffles and so this is causing the truck to pull oil from the covers as apposed to crank pressure. This would e plain the oil I also found in my intake. So we are gonna try and replace the covers and hopecully proper ventilation will solve this problem. But who knows. I might have broke a land on the piston and its letting pressure by. We will findout later this week.

 

As it turns out it was the valve covers. I bought some one inch spacers so I could use my factory valve covers. By using them I got my crank case pressure down and the truck is back to running great