Lifter Valley Tray
 

When I rebuilt my FE 390 I replaced the intake with a Performer RPM. Because the new intake does not have the exhaust cross over, I discarded the lifter valley tray. This was also after doing some research and discovering the lifter valley tray was intended to keep oil from splashing on the underside of the original intake and burning/crystalizing into chunks.

Now the issue - I have replaced my intake gaskets four times. I have read every post on the proper method for cleaning and prep and have followed them to the letter, yet I am still getting leaks at the rear of the intake. I am not using the end gaskets, I am making them out of RTV silicone (have also tried two different types of RTV). The engine is tilted down in the rear, thus allowing oil to naturally flow in that direction. A theory I want to throw out is with the oil on the underneath side of the intake could it possibly be preventing the RTV silicone from sealing properly? Even after I let it cure for at least 24 hours as per the directions. I have never had a leak at the front, however it is higher than the rear.

Lastly, assuming I get the RTV silicone to seal to both surfaces, would constant exposure to the engine oil (i.e. oil on the underside of the intake flowing to the rear of the engine and over the end gasket) lead to the end gasket coming "unstuck"? Do I need to put a lifter valley tray back in hoping this will keep oil from splashing on the underside of the intake and flowing to the rear over the gasket?

As I said, just a theory. However, I certainly appreciate any suggestions you guys can send my way. I understand FEs like to mark their territory, but it seems mine is being way too "territorial"!

Thanks!

Rick

Hmmm, that is strange. ONE good thick bead of silicone on the ENGINE and then set the intake in place should be more than adequate. No curing is really required and oil won't 'eat up' the silicone.

Somethings not right here. Is the motor ventilated properly? Like with a PC Valve? NO heat cross over on my high rise intake, thus, no valley cover required. The valley cover also keeps the intake cooler, it actually ADDS horse power, in some cases.

Check. PCV valve on one side and breather cap on the other. I have played this out a hundred times. What's the definition of insanity "When we do something over and over again, yet expect different results" - sign me up. Maybe I simply am not getting my silicone thick enough.

Could be you are not getting the silicone thick enough. Could also be the intake itself slightly out of square. I've seen several guys complain of this and did turn out to be the intake machined out of spec. Also were the heads or block surfaced before the rebuild?

G.

I believe FFR is correct about the thickness, What works for me....I lay a 3/8 bead down and a little extra where the intake gasket meets the block, after wiping the front and rear with thinner, wait until you can touch the bead without it sticking to your finger and place the intake. Torque to about 10Lbs
and wait until the next day then torque to specs. Trim any excess....

Be careful not to make the bead to thick. If it is to thick it may block off the head oil drain back passages. If you have the breather port in the back of your intake you can use an inspection mirror to check if the passages are clear after installing the intake.