Intake worries

[ThatOneGuy]

So I've been cleaning up some engine parts for the 4.0 today which has not been an easy task one of the nastiest engines I've ever torn down so much sludge everwhere. Any way once I got the intake 99% clean I started going over the sealing surfaces. The p.o. must have owned stock in permatex it was everywhere. I fact strips of it were in the oil pickup when I tore the engine down. Well once I got them clean I wish I hadent. What do you think caused this damage. Cavitation?, poor castings. Here is the question though should this be sent to the great foundry in the sky, or do you guys think it's salvageable. I currently don't have a gasket to compare the damaged areas too.

 

[sgtsandman]

That looks like pitting from corrosion. From the factory, those surfaces would have been machined flat. Which might explain the Permatex. Though the pitting doesn’t look bad enough to not create a seal.

They should still be serviceable. The strips in the pickup is from using too much. A little goes a long way if it’s really even needed.

 

[Eddo Rogue]

I would use em....maybe hit em with 2" medium to fine polishing discs on die grinder.

 

[ThatOneGuy]

Thanks guys

 

[55trucker]

You might inquire to your local machine shop what they would charge to do a flycut across both surfaces to clean them up...one doesn't want to remove too much material as this IS a tapered contact surface.

 

[19Walt93]

I wouldn't machine the surface, it'll make the manifold a little narrower and misalign the ports. Get some epoxy like JB Weld, spread a light coat over the corrosion and block sand or file it flat once it cures. You're looking at what happens when coolant isn't changed often enough or is mixed with acidic water instead of distilled. I have seen it before.

 

[55trucker]

Well, that's why I advised to ask the machine shop about this, they would know without a doubt how much could be safely removed before upsetting the manifolds position between the heads. I'm thinking .010 could be safely removed.

 

[RonD]

Yes, aluminum intake with cast iron heads = galvanic corrosion if the coolant gets too old, over 2 years old

 

[vagabond80]

if po invested in permatex, you should invest in 3M roloc bristle disks.
i love the things for surfaces like that

 

[Mac]

Well, that's why I advised to ask the machine shop about this, they would know without a doubt how much could be safely removed before upsetting the manifolds position between the heads. I'm thinking .010 could be safely removed.

.010 ' is the limit.

 

[ThatOneGuy]

Thanks everyone so between two options would you smothe the imperfections with high temp rtv or jb weld. I know jb weld says it will withstand temps around 400 degrees. F. Will the intake see temps higher than that, id assume no???

 

[RonD]

If it gets hotter than 275degF then you will have cracked heads, so lets hope not
Operating temp is 190-215degF, 1/2 on Ford temp gauge is about 205deg
Use RTV

 

[sgtsandman]

I would agree with the RTV. Just don’t do like PO and use too much. A little goes a long way.

 

[Shran]

I would probably use RTV there, just a tiny bit or it will mess with your gasket alignment. Walt's suggestion for JB Weld is great too if you trust yourself to get it flat.

 

[RonD]

And just as a heads up, use lock-tite on the lower intake bolts, they use very little torque(12ft/lb) and like to unscrew themselves during engine operation