Oil Filter Adapter

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Earlie A

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Working on a 1965 Dart with 360 and TTI headers. The oil filter adapter is leaking severely upon cold start up. The existing adapter is aluminum. Is there any benefit to replacing the aluminum with an iron adapter? I have to pull it off to change gaskets and mounting bolt anyway.
 
If it fits your car ok now, I don't see a benefit in replacing it with iron. An aluminum one is probably not a true 90 degree adapter like the iron ones that came on Early A bodies like your Dart, with 273 V8 engines. The later adapters like you have, will sometimes make the oil filter hit the frame rail. If yours isn't hitting, I wouldn't worry about changing it. Link below shows where all 3 gaskets go, but I always replace the fiber washer that goes under the bolt head with a big copper washer. Never had one leak there yet by doing that.
 
FWIW, I recall 4.0 Jeeps from the 90s used a 90 degree adapter. Probably <$20 at a junkyard.
 
Working on a 1965 Dart with 360 and TTI headers. The oil filter adapter is leaking severely upon cold start up. The existing adapter is aluminum. Is there any benefit to replacing the aluminum with an iron adapter? I have to pull it off to change gaskets and mounting bolt anyway.
The benefits I can think of are: Making it look more stock, improving the filter angle, and less prone to warping. There may be more..... The cast iron one adds a bit of weight though.
 
With the headers, the adapter is absolutely necessary. I'm wondering if other people have experienced less leaks with iron than aluminum. The oil leak is terrible when the car is cold, but goes away when the car warms up. Since aluminum expands more than iron and steel, perhaps the aluminum adapter is growing more than the steel bolt and the oil leak gets sealed up when the engine is hot. Would an iron adapter grow less than the aluminum one and crush the adapter gasket less?
 
I would think with the adapter, it wouldn't be as messy when changing the filter. You wouldn't have oil running down the block, it would drip off the adapter.
 
Here’s the pic of the difference in the iron adapters. The one on the right in the pic is what came on V8 Early A’s.

BD969318-1752-40B9-BB46-1D67BF3804DC.jpeg
 
Here’s the adapter. It is not the correct one for early A bodies. I found one on eBay, so I’ve got that covered. There are two gaskets stacked around the center bolt (see picture). Could this be the reason for the leak? Should the large outer gasket and the small inner gasket be the same thickness?

498E7F4C-2FEF-4575-A168-C0FFF7E30F65.jpeg
 
Here’s the adapter. It is not the correct one for early A bodies. I found one on eBay, so I’ve got that covered. There are two gaskets stacked around the center bolt (see picture). Could this be the reason for the leak? Should the large outer gasket and the small inner gasket be the same thickness?

View attachment 1716132391
Wow, that's a odd looking one!
 
Here’s the adapter. It is not the correct one for early A bodies. I found one on eBay, so I’ve got that covered. There are two gaskets stacked around the center bolt (see picture). Could this be the reason for the leak? Should the large outer gasket and the small inner gasket be the same thickness?

View attachment 1716132391
Pretty sure that is wrong.
Large gasket on block. Then adapter. Then small gasket on outside of adapter. Then bolt goes through everything.
 
Could not find a picture with that style gasket arrangement, but here is a thread with picture showing the other style gasket. The gasket without the center built in gets another small cork gasket between the adapter and block. But the one you have with three legs and a center does not use anything else there because you lose crush on the large outer diameter. Exactly the problem you had, I think.
Oil filter adapter gasket location
 
Here’s the adapter. It is not the correct one for early A bodies. I found one on eBay, so I’ve got that covered. There are two gaskets stacked around the center bolt (see picture). Could this be the reason for the leak? Should the large outer gasket and the small inner gasket be the same thickness?

View attachment 1716132391
Yeah, that's too much thickness in the middle, which isn't letting the outer ring seal as well. Look in the link I posted in #2 reply above. There is a pic that shows where each gasket goes. The fiber gasket that comes in the kit is supposed to go between the head of the bolt and the ring on the tube of the body of the adapter. I always toss that fiber gasket and use a big copper flat washer. I will try to find a part number for the copper washers and post them here. The ones I use are wider than the ones that come in the replacement bolt/gasket kit. They may not be any more benefit than the ones in the kit, but they make me feel better about the installation.....lol.
 
Oh man, sorry JDMopar, I must have skimmed right over your post. I ended up posting a link to the same one but you already had it right way up there.
 
Thank you for taking the time to respond. It’s nice to have a resource like this and knowledgeable people willing to share.
 
@Earlie A Hang onto that thin headed bolt! You can get 2 of the oil holes welded up, then step down a little ways and drill 2 new ones. The thin headed bolt is required with some TTI exhaust systems. @65barracudaLA had to saw the head of the bolt on his car off to get it to fit with the TTI head pipe he used on the factory passenger side manifold. I'm not sure if their headers require the same thing or not? If it does, I'd rather modify the oil holes than saw the bolt head thinner! Here is the pic he posted of his after he sawed it in two.....with a HACKSAW. :eek:
90 degree adapters - SBM.jpg
 
I do have TTI headers, and the thin bolt head almost touches. I bought a Fel-Pro gasket set and a hardened replacement bolt (all in a kit). The new bolt has a 1 3/16 diameter washer head under a 7/8 hex head. It’s a little thicker and stouter than the thin original 1 3/16 hex bolt. We’ll see what kind of clearance it gives.
 
If the TTI's were on the car when you got it, you can go to their website and download the installation instructions for the early A headers. You may have to use the old bolt back, but I'd fix it first. I bought a 90 degree adapter from @Mojack at a swap meet a few years ago, and he had fixed the bolt that was with it. The holes had twisted, but he welded 2 of them up, drilled 2 new ones lower, and then redrilled the big center hole. I cranked the pee out of it when I put it on a motor and it worked just fine. I tagged him so he will see this thread. He lives in Bristol, so all of us hillbilly's have to stick together, TN or NC versions!

:rofl:
 
Here's the washers I use between the bolt head and the adapter. You will need to hone the ID of them a little so they will slip on the bolt easier.

IMG_1743.JPG


IMG_1744.JPG
 
My bolt did not have either a gasket or copper washer, but appeared to be leaking mostly from the large gasket. Thanks for the source on the copper washer.

This gasket thickness thing has got me curious, so I did some measuring on a 340 block and the oil filter adapter. On the oil filter adapter, the inner (small) gasket machined face is 0.264 lower than the outer (large) gasket machined face. On the block, the inner face is 0.175 higher than the outer face. This means that when assembled, the compressed inner gasket should be 0.264-0.175=0.089 thicker than the compressed outer gasket.

It will be interesting to see the difference in new gasket thickness when my gasket kit arrives.
 
Good thread. Thanks. I'm trying to figure out why mine was leaking so bad so I don't have to do this again. I still haven't found the smoking gun.

Why did it leak (badly) when cold and stop leaking when hot?

The bolt was tight (at least relatively tight) and not stretched or broken.
The old gaskets (both inner and outer) had gray RTV on all sides. Is that bad?
The inner gasket area had the thin hard gasket and the foam gasket stacked, which appears to be correct for that gasket kit, but maybe that design of gasket kit is inferior.
Aluminum vs iron adapter. Has anyone experienced aluminum adapters leaking more?
 
Good thread. Thanks. I'm trying to figure out why mine was leaking so bad so I don't have to do this again. I still haven't found the smoking gun.

Why did it leak (badly) when cold and stop leaking when hot?

The bolt was tight (at least relatively tight) and not stretched or broken.
The old gaskets (both inner and outer) had gray RTV on all sides. Is that bad?
The inner gasket area had the thin hard gasket and the foam gasket stacked, which appears to be correct for that gasket kit, but maybe that design of gasket kit is inferior.
Aluminum vs iron adapter. Has anyone experienced aluminum adapters leaking more?
Neither should leak if properly sealed.
 
I've seen adapters (mainly aluminum ones) that were over tightened and would leak. What happened is that the center bottomed out before the outer gasket was compressed. It's easy to break the bolt tightening it that much too. I guess some people thought that such a large bolt needed lots of torque too.
 
From the measurements I took this morning, I don't see how the center can bottom out unless the gaskets are extremely thick and rigid. There is 0.089" more clearance between the center gasket faces than the outer gasket faces.

I stated earlier that my center bolt was not stretched or broken, but that is incorrect. It is not broken, but I can feel a small diameter change between the four holes. I think it is stretched. But it was still (fairly) tight when I broke it loose.
 
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