Help

I just put a rebuilt 390 into my 79 F350. I started with a rebuilt long block from an engine supplier. I have no real details on the engine. All appeared to be in order. I installed an Edelbrock Performer 390 intake, Edelbrock 600 cfm carb, aluminum valve covers, dynomax headers and the rest of the normal stuff. At first, my valve covers were leaking, so I replaced the gaskets with Fel Pro rubber types. That seems to have resolved that problem. But the evidence of the oil leak (pretty bad one at that) is still there (i.e. puddles and the smell of oil burning when it drops on the header collector). I looked and can see oil coming from between the engine block and the heads on both sides. I admit that I didn't verify the torque on the head bolts before installation (probably should have), but they were marked with white marks, which seemed an indication of the builder's torque verification... Anyway, is there any 1st step I should take in trying to resolve this, or am I going to just have to bite the bullet and tear the heads off and replace the head gaskets???

 

First I would call the engine supplier and talk to them ...they make just want you to rip out your engine and they will send you a knew one (PITA). If you dont have any sort of warrenty then I would go ahead and rip that engine down..(its really not that bad) and replace the head and intake manifold gaskets. I would really lookover everything else too as there might be other problems..Be sure not to mix up your push rods!

 

ab, If you have just install this engine, things should still be fairly clean. Wipe any oil away and run the truck. I suspect that it is leaking from either the front or the rear of the intake. I suggest pulling the intake if it is leaking, and put a 1/4" thick bead of silicone (black/blue) whatever, let it stand for 45 min or until it skins over and starts to harden. Carefully place the intake on and you should stop your leak.

 

Thanks.

I used the ultra black when I installed the head, but I didn't let it skin over for 45 min. I' m also not sure if I put a large enough bead on.

I cleaned the front of the heads off today with solvent (brake clean) and the oil came back. I can't tell whether it was from the corner where the intake meets with the head/block or if it's coming from between the head and block. If I had to guess, I'm suspecting the fault lies in my workmanship...ie.. not sufficient silicone. I will try to confirm source tomorrow.

Thanks again,
Arlian

 

I just cleaned the back of the intake off with carb cleaner and packed a ton of blue silicone in the crack where the gasket is for the rear intake seal. It quit leaking completely and no one can see the ugly job since it is in the back of the engine.

 

Thanks ratsmoker.

That is my next step as you are the second one to recommend it. I checked today and the leak looks like it is originating from the intake. I will use solvent to clean thoroughly (2 or 3 times), let it dry and then 'gob' it on with as much care as possible. Maybe that will rectify. This will be easier than jumping right into the removal of the intake.

Thanks for the help.

Arlian

 

Not to push any buttons but.....I thought that why they made gaskets. Now I agree that the oil leaks on these engines are a PITA , but i thought of the RTV as more of a temporary fix ....Just my opinion
Jon

 

Jon,

Thanks for the posting. I would normally agree. However, with the Edelbrock intake, they specifically tell you to throw away the cork end gaskets and use RTV instead. This was included on the instruction sheet, which accompanied the intake.

Thanks,
Arlian

 

He is right chas. I chose to not listen to edelbrock and ended up globbing RTV all over the back of the intake. Never use gaskets. Also let the thing set for a 24 hour period after you finish before starting it.

 

Dang, when I was doing this stuff regularly, we didn't have RTV. And by the way, it WAS uphill both ways and snowy even in May on the way to school.
I did my Dads T-bird after he accused me of blowing a head gasquet.. that turned out to be a freeze plug that had rusted through. Hmmm, maybe that is why it showed cold 5 miles from home... No antifreeze and it was froze up... and rusted thru.

Any way, we had cork and permatex. I got the job done.. What did I do wrong? I just don't trust the blue goo to do the job except at the corners. Course, I installed this pig intake by myself not knowing that it weighed what everyone claims it weighs... Yeah, it was heavy, but not that heavy. Umm, this was in 1965, so maybe I was stronger then.. I just remember plunking it down on the cork and hoping for the best...
tom

 

I never had a problem with the stock cast iron intakes either using the cork gasket with RTV in the corners. I think the edelbrocks are higher at the seam than stock ones are.