I rebuilt my 400 in my 77 f150 , and now it has a high pitch whistling sound ever once in a while , it dont do it constantly....... all of my vaccum lines are hooked up and new.......i talked to a guy other nite that rebuilt his 460 in his 79 and he said his done the same thang , and it was leaking around the intake..... he told me what he done to stop it , but i dont remember. Does anybody else know anythang about this kind of problem? I know theres not a gasket between the intake and the heads/block , its just got that metal pan...... If anybody has any ideas post them up. I gotta get it fixed , it gets annoying.

Thanks
-Dustin

 

I had a similar exterience with a 460, using the "pan" type intake gasket.
The fix was to pull the intake and replac the gasket / pan. Found that I had caused the problem when I used gasket cement on the heads and intake. I installed the new gasket dry, no sealer, no silicone, nothing on the heads or head side in the intake. I did use silicone sealer on the "ends", where the block and manifole meet up.
Hope this helps.
Roger Carter

 

I didnt use any sealer on it....... Cud it still be possible that thats whats wrong?

 

when it does it is it while idleing or while driveing or is it completely random?