Oil pan studs or bolts?

[lippy]

Here is the pan rail I made. It's not as slick as Wiki's, but I liked making it myself. I used 308 SS bar, 3/4" x 1/8", cut it, and TIG welded it. In order to get it flat and reasonably clean, I tacked it on one side, then the other on each joint, and then welded. I found that if I paid attention to the cuts and made them clean and tight, I could fusion weld (no filler rod) and the welds turned out much better. At any rate, it took a few hours (probably 5) but I'm happy with the results.

Now on the studs vs bolts... Between the two gaskets, the reinforcement, the pan, and the windage tray, the aggregate thickness is about 0.48", maybe a bit less. The bolt holes in the Pond block are about 0.5" deep, but they vary. If I use bolts, the 1" ones may bottom out, and the shorter ones (0.812") would only go into the block about 0.3", which isn't enough. I'm told you want to go 1.5x the bolt diameter for steel and 2x for aluminum, so for 5/16" bolts I would need the full 0.5" in my block, as it's aluminum.

Which leads me to studs. I have the Canton ones already (which loosened) but I'm thinking it may be worth it to spring for the ARPs. They are slightly better because (1) they use a higher strength material and finish, and I can torque them to 20-22 ft-lb, which will better take advantage of the reinforcement I made, and (2) they use coarse threads into the block, and fine threads on top, which i'm told provide better clamping force, and are less likely to back out.

[DanEC]

Wow - that's nice work Lippy. Shouldn't show too many pictures of those as you will start getting inquiries to produce them. FWIW - I think studs are the way to go, especially with an aluminum block. Do they have an allen screw recess or screw driver slot to help tighten them? I can't see what a little blue locktite would hurt to keep them tight to the block. But then the tensioning by the nut is taken up in the stud and there's less risk of galling and stressing the block threads by the combined action of tensioning and friction when tightening everything down. Maybe an ME can address that better than this aging CE.

[lippy]

Well, I'm an aging ME so I don't remember most of this anyway. The Canton studs have an Allen end but they are all coarse thread and don't have a shoulder. The ARPs have a shoulder so they can be snugged into the block, and they are fine thread on top, but they don't have an Allen hole. Instead, they have a nose so the nut starts easier. I guess you can double nut them if you need to take them out.

They don't make a stud kit for FEs and the bolts they have for FEs are too short if you use a reinforcement. But the Pontiac/Mopar kit works. ARP 200-1901 and its variants for 6/12 point stainless/oxide. While these seem expensive at $70 for the kit, I priced out McMaster-Carr and the studs and nuts were more expensive, not the ideal size, and not as strong. So not a bad deal.

[lippy]

Update: I got the engine back together and the pan on. I used a new set of Canton studs with the rail shown above. This way I was able to put more torque on the studs (about 13 ft-lb), hopefully stretching them enough so they don't come loose. The method I used was to first glue the gaskets to the windage tray and then use The Right Stuff to attach that assembly to the block, using the rail as a clamp. It made the whole process easier, as I could let that dry, then take the rail and nuts off, put the pan itself on as a last step, and tighten down with the rail. This way, I was in far less of a rush to get everything together before The Right Stuff set up, which is quick.

I've put about 100 miles on the car since I put on the new gaskets and studs. No leaks so far. But every time I retorque it, which has been I think 3-4 times now, the nuts need about 1/8 turn. I should be past the gasket compression phase by now. Anyone have an idea what might be going on? I'm worried that as soon as I stop tightening them, It'll start to leak.

[patrickt]

Originally Posted by lippy

But every time I retorque it, which has been I think 3-4 times now, the nuts need about 1/8 turn. I should be past the gasket compression phase by now. Anyone have an idea what might be going on? I'm worried that as soon as I stop tightening them, It'll start to leak.

No chance the studs are backing out?

[Bernica]

Any chance of heat cooking and shrinking things a little? "Snug" seems to work, but over tightening over time doesn't seem to....
If it's not leaking, I wouldn't touch it!
My 2 c...

[lippy]

I don't think the studs are backing out, but if they are looser once again I may pull out a few and add Loctite.

[DanEC]

I've noticed that pattern with oil pan, transmission pan and valve cover gaskets - I assume the gaskets are compressing and losing their elastic compressibility under engine heat. In this day and age you would think they would have some miracle polymer that would not do this.

[Dimis]

Originally Posted by lippy

I don't think the studs are backing out, but if they are looser once again I may pull out a few and add Loctite.

You could probably use a marker to confirm if they are backing out.
If they are, then perhaps a bit of Loctite as you suggested.

[Bernica]

Originally Posted by DanEC

I've noticed that pattern with oil pan, transmission pan and valve cover gaskets - I assume the gaskets are compressing and losing their elastic compressibility under engine heat. In this day and age you would think they would have some miracle polymer that would not do this.

Oh, there's some nasty industrial / aerospace stuff out there that hasn't quite met all requirements for consumer use. Some are amazing and some are just plain over the top! Like... once you seal it, forget it unless you want to use hard core methods to take it apart.

[55312]

Look at the 4th post on page one of this thread. BTW, I used red loctite on all the studs.

Tim

[lippy]

Originally Posted by 55312

Look at the 4th post on page one of this thread. BTW, I used red loctite on all the studs.

Tim

Why red and not blue? That would seem to create a big issue if you ever needed to remove 20 studs under the car.

[4pipes]

I think you're still compressing the gasket and RTV, I'd stop tightening.

[55312]

loctite grade is besides the point (the studs came out with a little extra torque). The point here was the constant loosening of the nuts and the only way I fixed it was to replace the stud set up from Canton with ARP Bolts.

Just my experience.

Tim