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KTL KTL is offline
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Join Date: Sep 2000
Location: Frankfort IL USA
Posts: 16,643
I'm no pro and just above a hack. So take my advice with a grain of road salt.
  • Lightly beveling the case through bolt holes with a countersink to minimize the amount of o-ring murder that occurs when you tighten the through bolts. It seems that the o-rings in the gasket kits are larger than the originals and that creates more crush than desired.
  • The recommendation in Wayne's book to use RTV silicone as a "belt-and-suspenders" extra measure of protection in the through bolt sealing area is not my cup of tea since I have a massive fear of that stuff and hate cleaning it up after it's cured. So I won't get into that debate. Ooops, I just did but let's not go there.........
  • You'll likely notice that the interface of the main bearing saddles looks like it was machined differently than the case parting line, if untouched (not likely since you're assembling a 2.7 mag case). That's a sign of shuffling going on there. Use a very very very thin coat of 574 here, since it has some shear resistant ability unlike most other sealants.
  • Break the sharp edges of any oil passages with a fine file. Like the oil inlet port behind the oil cooler and the passages where the oil pump mates with the case halves
  • DON'T use Curil T on the periphery of the radial seals for the crank. That just invites the seal to walk its way out or leak. All you need is a bit of spit or water or whatever to provide some slip in the rubber-aluminum interface as the seal moves its way into the bore. You want whatever "lubricant" you use to dry and no longer lubricate after you're done installing the seal. Curil T never cures. Funny how its name has cure in it........
  • Lube the lips/ID of the seals with a swab of oil to avoid a dry startup. Also put some dabs of grease on the garter spring to hold it on there, in case you choose to drive the seal in place with a suitable guide piece and hammer, so the spring doesn't hop off the seal.
  • Thinner is better when it comes to sealant application. Especially when it comes to the cam housings- just a paper thin layer around the openings for the valves and the bolting holes in the cam valley. DO NOT coat the entire machined underbelly in orange (if using Loctite 574) like Wayne's book shows. That's completely unnecessary and makes for a TON of extra squeeze-out, and future cleanup, the next time it's disassembled.
  • Check the flatness of the cam bore at the gasket surface where the thrust plate mounts to it. This area is sensitive to leaking & the amount of contact surface for the gasket is quite small given the width of the gasket here. In fact this area is often not all that flat on the cam housing itself. You can verify this by coloring it with a permanent marker and then rub the housing on a known very flat surface with some 400 grit wet sandpaper. You'll be quite surprised how much marker does NOT rub off after a handful of passes across the paper. Also a good idea to check the thrust plate for flatness. That's an easy one to true up.
  • After you set that thrust plate in place (use some silicone paste or oil on the thick o-ring to help slide the thrust plate home), check behind the chain box to see that the gasket has not gone off alignment.
  • Make sure the epoxy on the back side of the chain boxes is not applied too thick. Too thick and it'll contact the cam housing and the above gasket can leak badly.
  • Use a false/mechanical tensioner set to set your cam timing. They allow you to turn out the adjuster bolt and therefore set your chain tension by "feel" vs. just clamping the chain with a vise grip/welding clamp or whatever. It'll make you feel better about getting your timing the same on both sides. Also nice to have two Z-blocks and dial indicators so you can see your timing on both sides- reduces setup error by transferring the block + dial setup to the other side. I really don't care for the alignment that the Z-block establishes for the dial indicator plunger. Stomski's setup is better for placing the plunger at a perpendicular to the valve spring retainer.
  • Make sure your four inner chain ramps engage the mounting bolts properly inside the case. It's easy to think the ramp just pops onto the nipple of the bolt quite easily but it doesn't. The ramp just gets pushed against the back of the case and doesn't fully seat onto the bolt. Yes, the ramp isn't going to fall off the bolt. But the ramp isn't well aligned with the chain.
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Kevin L
'86 Carrera "Larry"
Old 01-22-2018, 01:49 PM
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