Well, I finished my conversion and fored the bike up yesterday. I rode it aobut 20-30 miles between yesterday and today.

Noticed my stock lifter blocks are seeping oil.
I installed them in the correct holes and with new o-rings. I slightly dabbed oil on the rings before installing, so that they won't tear on the way in. Torqued them to 13 ft-lbs as per the HD manual.

I have read that the 5-speed block are made of pot-metal crap and can warp and leak.

Is this also true of the 4-speed blocks? They look to be beefier than the 5-speed blocks and I believe install differently, and are of a totally different design. (the 4-speeds use the same lifters as the 80" Big Twin Evos)

I will try and torque them again when the motor cools down, but I doubt that it'll help.

Anyone have experience with these 4-speed blocks?

I know S&S maked Billet blocks for 4-speed, but they cost $250...!!!!
Stock HD blocks cost like $90 for the set.
I didn't want to get the S&S ones for cost sake, but it looks like I should have...I'm pissed.

That Sucks, I read a thread some where here that if you go up one size thicker on the o-ring it would seat the old style block better. I did when I had mine torn down and they dont leak (yet). They did before I did work on the motor. I know its kinda late info. Good Luck

the lifter blocks were pretty tight going back in at the o-ring. I don't think the rings were too small.
I spoke to Dan at NRHS, and he said that the 4-speed lifter blocks are far superior to the 5-speed blocks, and that they shouldn't really leak. IT cost too much money for HD to make them, so they switched to the type on the 5-speed.

I also started to think about my crank case breathing. Somehow, it seems that my cam chest is pressurised or something. My breather is working, I feel it pumping out from like 10 inches away.

My head have breather provisions in them, and I thought that maybe I should use them.
So I took off my carb backing plate and the bolts I used to block them off.

But check this out, I posted a while back about my front and rear rocker boxes being different.
Rear:
http://xlforum.net/photopost/data/500/medium/129_2990_1.jpg
front:
http://xlforum.net/photopost/data/500/medium/129_2992_1.jpg

Seems that my rear box is an updated "top breather" designed for the forward move to cylinder head breathing. The front box is the old style one. Both stamped in 1988.
This means that only my rear cylinder head will breathe if I want it to.

But anyhow, letting my rear head breathe didn't do much to stop the oil seeping out of the lifter blocks.

I am frickin stumped...

I just posted on the same problem after I finished some engine work. I had small leaks at the lifter blocks and bottom cylinder gaskets, was running rough at idle and couldn't get it tuned just right. My crankcase vent line was putting out some serious pressure also. To make a long story short I discovered the vent line off my oil tank had collapsed and that inturn was building up pressure in the engine which was causing the leaks and the rough idle. I fixed it and everything is mint no leaks runs great.

I just posted on the same problem after I finished some engine work. I had small leaks at the lifter blocks and bottom cylinder gaskets, was running rough at idle and couldn't get it tuned just right. My crankcase vent line was putting out some serious pressure also. To make a long story short I discovered the vent line off my oil tank had collapsed and that inturn was building up pressure in the engine which was causing the leaks and the rough idle. I fixed it and everything is mint no leaks runs great.
hhhmmmm...

I'll have to check that.
I had forgotten that there is the vent line in the cam cover...Are you supposed to feel pressure coming out of that line into the top of the oil tank?

I just went out and started my bike and checked the CC vent line. Now that I have fixed the kinked line on the oil tank I isn't blowing off much at all nothing compared to what is was when it was screwed up. How I checked is with the bike off (of course) I blew into the oil tank when I had the restriction it would build pressure after I fixed the line it didn't build any, I could hear the air blowing out in the cam cover. When I upgrade my rocker covers I got the new styles but if you are still venting from the crank I don't think they should make any difference. I hope it's the problem its an easy fix,I was about to rip it down again

I have never had the blocks on my leak. I have only had it apart once to change cams and to get new valves reseated. you might have crushed a o-ring pushing it down or unseated it from the groove. as far as the vent lines go. I can feel the crankvent like 6 inches away of dry but oil-stinky air. and the line going to the oil tank does blow a lil bit of oil back into the tank. but no leaks but for a small seep between the cases.

I just started the bike, and I felt a vacuum at the oil tank vent line. It wasn't blowing out, just sucking in. With the line attached to the tank, I held my palm up to the oil tank plug hole, and it was pulling the oil tank into a vacuum. So that would mean that my cam chest is actually in a vacuum...so why would the lifter blocks seep oil???? this is getting wierder by the second...

It's all 4 lifet blocks that are seeping, not just one. I couldn't have torn o-rings on each block...

I was just thinking, since it is a new engine and it hasn't seated yet you are getting a TON of blow bye and since our bikes are vented from the crank it might put more pressure on the orings especially with the 10.5:1 All those leaks might disappear when it breaks in.

I will go start my bike and see if I get the same thing.

I just checked I have a bit of vacum also and when the line was kinked it was pressure. So this means the pressure causing the leaks has to be coming down the pushrod tubes and not up from the cam chest.

have ya got a pic?

I thought about the o-rings on the lifet blocks themselves, where one is thicker than the other. It was my co-worker that installed the new o-rings, and he swears that he put them in the right way. One o-ring groove is larger than the other, and it would be hard to screw that up.
then thought about the pushrod angles of the 91-up heads being slightly different, but that shouldn't matter, and MOREHP, you have XB heads on yours...and no leaks.
I really don't know what to say...

I still think after the pistons seat your seeping will stop. When I had the line kinked it was building up Crank case pressure and I had o-ring and gaskets seeping. When I say seeping I mean air and oil coming by the seals sometimes it would even bubble out. When I removed the kinked line it reduced the CC pressure and everything was good. You have a shit load of blow bye going on right now and it is doing the exact same thing inside your engine that my kinked line was doing to my engine, probably more so. I would put some miles on it before I started to think about taking it back down. Also My conversion was already done when I got the bike so I don't know how it acted when the conv. was done. What I do know is when the o-rings fail in our style lifter blocks they spew oil, the shit goes everywhere. So if you have 4 just seeping there are other forces at work. I'll keep thinkin on it. GOOD LUCK

I'm going to open the one head breather, make it operational and see if it does anything in the long run. If after I I put a bunch of miles on it, and it doesn't stop, I'll have to look into it deeper, maybe even remove the lifter blocks and see what's up with them...
thanks for your info.

I spoke to a few other mechanics and my local HD as well.
Couple guys were stumped, and the HD mechanic who used to work at my local Indy shop, said that it sounds like the lifter block o-rings just aren't sealing. He said to break the engine in and then open it up again afterwards.

I bought new o-rings for when that time comes...