Changing the exhaust manifold gaskets on my 78 F150. Its a 351 (really not sure which one). The questions I have are:

1) Where can I find a replacement set of exhaust manifold bolts (a few of mine were damaged when I took them out).

2) has anyone used the aluminum "reusable" gaskets and if so how do they work out.

 

Hi plcdwg101,

When I did the exhaust on my 460 I tossed ALL the bolts that came out of it. They were a mess. I went down to the hardware store and purchased grade 8 studs and flange locknuts (NOT the ones with the teflon insert). Used a thread chaser (not a tap/die set) and clean the holes out, especially any blind ones. Shoot some brake clean in the holes to clean, blow out with air compressor, put just a dab of hi-temp anti-seize on the stud motor side threads and install.

My thinking was if I have to remove them either the stud or the nut will be able to turn and avoid breaking bolts. Our local Ace has an incredible hardware section.

If you don't want to go that far, take your bolt down to the hardware store and find a grade 8 that is the same thread/length/head with a hardened lock washer and it will be fine.

As for the gaskets - I suppose you could, but I don't re-use exhaust gaskets. Just a personal preference. You should be able to pick them up for less than $15 a set.

Remember to check the bolts after you heat it up a few times to make sure everything is staying good and tight.

 

Ford did not use exhaust manifold gaskets on 351m 400 or 460 engines .I would clean and sand mating surfaces of cylinder head and exhaust manifold.Check manifold for flatness with level or straight edge. you can use gaskets if you want but I have never had a problem running metal to metal on these 3 engines .On 360 390 engines that's a whole different story .I have had to double the exhaust gaskets to get them to seal they were really prone to warping .

 

I agree. 351M/400's never came with exhaust manifold gaskets from the factory so I don't use them either. I just put a coating of graphite based anti-sieze on the mating surfaces to help with heat transfer between the head & manifold. Zero leaks in 400,000 miles. If you don't need gaskets then don't use them. I always thought that manifold gaskets can cause harm too by not allowing even heat transfer and possibly resulting in warped manifolds. If they are bolted solid to the head without gaskets then it sort of makes sense that they are not going to move or warp.

Manifold bolts--check AMK Products website. They sell manifold bolt sets and sell individual bolts for many different engines. The AMK bolts will be just like the originals.

MeanGreen460: I am working on my first 390 for a 1976 F250 and it didn't use manifold "gaskets" either but Ford actually used tin heat shields instead of a fiber/composite gasket that most people would use today. Now, I realize that 360's & 390's are notorious for manifold leaks but I plan to install mine with the tin shields that Ford used originally. Do you have any experience with the tin shields/gaskets that Ford used originally?

 

Red Mercury I used to work on a lot of 360 390s over 30 yrs ago .Exhaust manifolds were a pain on these engines. First was getting them off .then you would put a straight edge on them see how warped they were then have them milled straight .I believe they came from the factory with a metal gasket .the steel gasket was prone to rusting out creating leaks which led to warping.If you have the manifolds milled flat and heads are nice and flat yes go with the metel gaskets but for better sealing you may want to use a metal gasket with a coating of asbestos or what ever the coating they are putting on them these days .Like I said sometimes you had to double the gaskets to make them seal good. I know I H used to make copper ones for the 345 and 392 engines Copper ones if anyone makes them for a 360 390 would be the way to go.