Yj with snowballing issues please help

Cacarter126

New member
So this process started with an 89' carbed yj that I recently purchased. I knew the carb needed a rebuild but I decided to buy a mc 2100 and just replace it instead. Here is where the issues started. I started looking around to see how complicated the install would be and discovered about a half inch of oil in my air cleaner. I assume it's coming from my PCV valve and if there is a fix out there the help would be much appreciated. Also, how intense is the swap between the Carter and the motorcraft? I have the transfer plate and gasket and electric choke already on the carb. Is this something I should hae someone do or is it something a novice could achieve. I purchased the mc 2100 from the eBay guy that sells the kits. That is the first set of issues.

The second set of problems deals with shackle lift that I recently installed fom full traction. Before the install I noticed transmision fluid where the drivshaft met the transfer case. Not very much at all. After installing the shackles the leak increased considerably. It throws transmisson fluid all over the undercarage. I don't know if this could be a seal or what, but it certainly wasn't helped by the increase in driveshaft angle. Which leads me to my next issue...dreaded driveshaft angle.

I was stupidly un informed that this would be such an issue. Since puting the shackles on, I have a vibration that I now know I should have known would need to be addressed. What are my options in correcting the angle? Transfer case drop or sye? I'm kind of clueless in this.

This leads me to my final issue. After installing the shackles and puting the weight back on the springs, the front springs are literally flat if not almost bent in the opposite direction. The shackles in the middle of the vehicle ( so the rear shackles on the front springs are hanging straight down if not slightly angled back. I actully lost ground clearence because the hanging suckle just described is lower then my pumpkin balls? Is this right?? The whole thing just looks unsafe. Is this correct? Are my springs to weak and can't hold their arch? And should the the center shackles e angles back? Could I solve this by leaving the very front and very back set of shackles and removing the center (rear shackles of front spring) ones. Simply bolting the rear of the front spring back to the frame, effectivly forcing an arch. Or are new springs needed?

I know this is all a lot and I'm sure I sound like an idiot but I'm really stuck and don't even think the think is driveable. Please any help is very much appeciated. Also I appologize for any spelling error, I types this on my phone.
 
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Issue #1: The reason you're getting oil blowback into your air cleaner from the PVC is because your PVC valve is not working, therefore not circulating air through the valve cover like it should and spitting oil up the backside tube. Replace the PVC and that backside tube, because it's oil soaked now. As far as the MC2100 goes, I'm one of the lucky ones with a working Carter...can't help ya there.

For a couple of your other issues we need to know how much lift you have now, and what type they are. I have 4" of lift with 33s and my t-case drop works perfect.

Don't worry, you're not an idiot.
 
Thanks man, the lift is a full traction shackle reversal which was supposed to give me 2 inches of lift. What do u think about the springs? if I have to replace the springs won't that lift it more and therfore screw up the angle again. Should I fix that first?
 

Unfortunatley no, I've got the carb, transfer plate, gasket and electric choke wich is already on the carb, that's it. That and figuring out the vacum setup i feel will be the hardest part.
 
I can help you with the MC2100 install.

I am assuming you are referring to the carb base adapter as the transfer plate.

The linkage is easy if you cut the throttle lever off the Carter BBD.

Only the part that has the ball stud that connects the bellcrank, or vertical link.

If your MC2100 has a throttle lever like mine, there is one hole on it, that will line up with the BBD's lever chunk you cut off. after the MC2100 is mounted you put the two levers together with the one bolt that lines up.

Then you take the slack out of the linkage & mark the second hole.
This should give you about 1'2 a hole through the MC2100's lever.
That will be enough to keep it together, just use small screw/bolts & nylon lock nuts.
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In this pic you can see the closer bolt that catches 1/2 a hole on the other link.

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Return springs, use two in case one ever breaks!
IMG_0193-3.jpg

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Pcv tees into the carb base & continues on to the charcoal canister.
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CTO switch should remain connected;
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vaclines_199878-2.jpg

This pic shows the PCV line in front of the carb for clarity.
Real world setup connects to the carb base at the rear of the carb.

There is a ported vacuum barb in front of the choke for connecting the distributor advance.
The port on the front of the carb (drivers side) should be capped or plugged.
Also plug the barb hanging down behind the carb (points toward rear of engine block).

If your MC2100 is like mine, there is no connection for a carb bowl vent.
Plug that line at the charcoal canister if so.

PCV breather;
IMG_0206-2.jpg


I moved my PCV valve to the rear port on the valve cover, so the sweet bling breather would be up front. There is no difference in the air flowing either direction, as long as on is an air inlet & the other leads to the carb base.
 
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What I would say about the slip yoke leaking is that it's from a preexisting condition, which was only exacerbated by the slight amount of lift you gave it. Two inches would not have caused a healthy t-case to go south so quickly.

As far as the springs, a flat spring is not a bad thing; after all, that's how it came from the factory. What they should not do is invert themselves. Your springs are probably 20 years old and had a good run. If you don't want anymore lift Full Traction sells 0" lift springs that are perfect for what you're looking for. Front part # FTSJYJ101F; rear part # FTSJYJ102R. Normally they're used for someone doing a spring over axle (SOA) setup, but they'll work for you. Be ready to shell out another $300ish.

If it were me, I'd order the new leafs, junk yard ones will give you the same problem (old age). I'd get a t-case drop kit, and I'd tear into the t-case tail shaft and order any seals I see in there.

There's a million ways to skin this cat, and you'll probably get a few more courses of action from other members on this thread. All of them will work, you're just going to have to make a decision that fits your wallet and desired endstate.
 

Issue #1: The reason you're getting oil blowback into your air cleaner from the PVC is because your PVC valve is not working, therefore not circulating air through the valve cover like it should and spitting oil up the backside tube. Replace the PVC and that backside tube, because it's oil soaked now. As far as the MC2100 goes, I'm one of the lucky ones with a working Carter...can't help ya there.

For a couple of your other issues we need to know how much lift you have now, and what type they are. I have 4" of lift with 33s and my t-case drop works perfect.

Don't worry, you're not an idiot.


I don't want to be the wet blanket here but if your YJ is running the original motor just changing the PVC may not do the trick. It could be blow by from the ring failure. That allows pressure to build up inside the crank case and it has to go somewhere forcing oil out and into the filter box. This is a common problem. You can drive it for some time that way and I have seen people get a sports bottle and tape it inside the engine compartment and run the hose to the bottle to keep the drip down. You do need to empty it from time to time.
 
I had the same problem with fluid leaking out of my extension housing, (cone on the rear of your T-case). BE CAREFULE!!! I had a SLIGHT leak, and in my infinite wisdom decided to replace the oil seal, (getting the old one out was one of the most frustrating things I've ever done in my grease monkey history). I think I may have messed up the housing b/c after putting it all back together... I have a WAY WAY worse leak than I did before...huge bummer. Hope you have better luck than I did.

-Boze
 
I had the same problem with fluid leaking out of my extension housing, (cone on the rear of your T-case). BE CAREFULE!!! I had a SLIGHT leak, and in my infinite wisdom decided to replace the oil seal, (getting the old one out was one of the most frustrating things I've ever done in my grease monkey history). I think I may have messed up the housing b/c after putting it all back together... I have a WAY WAY worse leak than I did before...huge bummer. Hope you have better luck than I did.

-Boze

Same thing happened to me. Recently, I found out there is also a guide bushing inside the tailhouse.

The slipyolk spins inside the bushing, & is held true by it. If this bushing gets to be too worn, it can let the yolk wobble slightly. That can wipe out a seal rather quickly.

I may go back & replace it someday, but I'd much rather get an slipyolk eliminator instead.
 

WOW! Good post Paul.

A picture is worth a thousand words, & it may have taken that many words without the pics I posted to explain it all.

As far as the info goes, there is more than I have time for.

I posted the what I feel is needed to get started, J/U's archives contain all you'll ever need on the subject of the MC2100 swap.

Only thing is, it could take days to read through all of it.

If your doing the swap, it's worth the effort though.
 
If your looking for springs and an easy lift, try Ruff Country. I'm not a spammer or work for them but for under $500 you can get 4 new springs, shocks, transfer case lowering kit, front stabilizer and the sway bar/ trac bar links.
 
Thanks for all your help guys. Ill let you know how everything works out. I went with new springs and I'm going to try and install the carb this weekend, as well as drop the transfer case and change the seal.
 

.... drop the transfer case and change the seal.

Don't forget to see about that bushing too. If the slip-yolk has a loose fit beyond the seal (bushing rides on the same surface as the seal, around the yolk's outside diameter only closer to the end of the yolk) then it may need to be replaced, or the new seal could only last a short time.
 
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