I’ve done a bit of research but I can’t find any definitive clues as to what my leaks are. I’ve got a leak that I have isolated to the aft section of my engine. I’m not sure what to look for to prove that it is a rear main seal but I do believe that it could be my oil pan gasket so I’m going to order one of those. Then I stumbled on a crucifix seal in a thread but I found no real pointers about how many there are, what other seals I can replace/need to replace while I am there, if anyone can answer those questions along with some pointers on how to do it. I can follow another thread about doing the oil pan gasket, that seems pretty easy.

Thanks for your help

oh and if anyone has a cheap pair of exhaust manifolds, let me know... <60

 

Have you done the PCV mod yet? Start with that first, it helps reduce the top end leaks so you can determine the source of the leak. There is a section in the Rave on the crucifix seals, and if you are going to take the pan off you should definitely do those while you are at it. Nothing else in there to replace at the same time.

Why do you need exhaust manifolds? You can drill out the studs and replace them with bolts if needed.

 

PCV mod has been done. Good to hear there isn’t anything else, I’ll check the rave before I get at it. Do you know off the top of your head how many I need to order?

As for the manifolds, I have 3 different sets (titanium) and none of them will cut through those studs. I was told I need a set of cobalt bits but a set of those is almost as much as new manifolds... more if someone on here has an extra set for cheap.

I’ve also never really drilled out a stuck bolt, do you know of any good tutorials? I’ve got a tap and die set, not really experienced at all with it but I get the process, but the way everyone talks about drilling out bolts it sounds like the threads remain afterwards which I don’t understand. If you have any pointers that can make it sound easier maybe I’ll just go grab the cobalt bits and then I can keep them on hand for the future

 

You don’t need cobalt bits, what you need is a good center punch and a steady hand. You will also need to take the manifolds off of the engine where are you can do this on a bench. Well, you don’t need to but your success rate goes through the roof comparatively. The broken bolts are relatively soft and easy to drill through with a sharp bit. I’m assuming broken bolts are your problem. If there’s anything sticking out then you may be able to soak it and then heat it with a torch to break it free and spin it out with vice-grips. I was lucky and got all my broken ones out this way. If not, the way to achieve the most predictable outcome is to take a grinder with a cut off wheel and remove as much of the broken stud as possible. You want a nice flat surface on which to place the center punch.

Punch it as close to the center as you possibly can and then use a 1/8” drill bit to drill a small hole through the exact center of the broken bolt, using lots of PB blaster or equivalent while you’re doing this. If you’re really lucky, the bolt will spin out the backside of the manifold as you’re drilling through it. Since this is a pretty rare occurrence, the next step is to get a slightly larger drill bit, maybe 3/16ths and enlarge the hole further, again using lots of penetrating fluid.

You can try your luck with a screw extractor and try to reverse out the broken piece but if heat and vice-grips didn’t get it to budge a screw extractor probably won’t either. Next you can drill it out to 17/64ths and try to chase the threads with an M8 x 1.25 tap. At this point the only thing left in the hole will be the little rings of thread from the old bolt. With any luck your tap will chase those and you’ll end up cleaning up the original threads in the manifold. this is where a very steady hand is critical. Or you can skip this and drill it out with a 5/16” drill bit and tap the hole for a 3/8-16 bolt, which is just larger than the original stud that was in there.

Oh, search here for crucifix seals. There are two types and the larger style seem to be the ones you want. It’s been discussed here recently. There are two seals in your engine.

 

Great instructions! I’m thinking my drill bits must be dull and I’m gonna try and sharpen them first because they will not cut through these bolts at all.

Ive already got the manifolds out and tried heating them and using a vice grip but it just mends the bolt and they don’t budge, which also doesn’t make sense as that would say that the bolts are soft, yet none of my drill bits will cut it! They’re Milwaukee bits so they aren’t some cheap harbor freight brand. I don’t know but I’ll figure out how to drill them one way or another.

I appreciate the number on the seals, I’ll try and look for a source of the larger ones but all I can find here in the states is the smaller one.

Appreciate the help!

 

Buy oem style cruciform seals from Bearmach, 2, one for each side, around $3 each.
The Allmakes are a different design.
Make sure to use rtv silicone in the cruciform grooves in the main cap.
And make sure to razor blade off the excess seal ends that protrude

from the cap, Before installing the cap. If you don't, the seals will leak, and the bearing clearance will be too large.

 

Cruciform seals go in the main bearing cap, one on each side.
Make sure to cut the protruding part of the seals off of each end of the cap.
The bottom Before installing, and the top side after the cap is installed.
(Notice how the Allmakes design does very little for sealing at the cross point in the grooves)

 

Cut these circled ends off flush(razor blade is easiest way).
On BOTH sides of the cap, 2 are pictured, plus the 2 oppsite ends, so 4 seal ends total, cut flush to the cap.

The short arms of the cross seal will Not fill the entire groove either, so fill in the rest with rtv silicone(as well as rtv under the entire seal).

 

https://bearmach.com/main-bearing-cap-seal-br-3374

They are cheap enough that it's adviseable to buy an extra set too, just in case you screw one up.

 

Awesome write-up! Really appreciate it! Do you have a source for the bearmach parts in the US? Ordering from their website is about $20 in shipping + parts. Looks to be the only one still selling that style so I'll get them worst case, but just curious if they are here already and I can skip the shipping.

Edit: Just saw your post from their website, I'll assume that's the only place to get them. I'll get them on order! Thanks!