Bell crank concerns

Bell crank concerns
billyocup

billyocup

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Location
Arnold, CA
Vehicle(s)
75 CJ5 304V8 T15 D20 D44 D30 2 1/2" lift, 05 Victory Kingpin, 2011 GMC Sierra 3500 Diesel 4x4
I just re-installed the engine, tranny and tc back in my 75 CJ5 . I dropped the tranny about an inch to compensate for the suspension lift (still not sure if that's enough) and I noticed that now the bellcrank pivot studs no longer line up (see pic). Is this going to be an issue? Do I need to modify or build a new bracket for the one mounted on the bell housing to raise it up, or will it work as is????

Thanks, Bill :chug:
 
Wow.. thats a nice set up. Normally with 76 and newer CJ's the one end of the bell crank is attached to the frame and when you put a body lift on the same angle occurs. then when the jeep flexes the Z-bar falls out. So imagine being on a rock or obstacle and your z-bar falling out!
 
How much did you raise the suspension??

fabbing a new pivot for the engine end will not be too difficult.

On my 77 the outside mounts to the body rather than the frame, with a 1" body lift I got about the same situation , just backwards. I ran it that way for quite a while before getting ambitious enough to re drill the outboard mount. I had no problem but it does put a lot of wear stress on the nylon pivot bushings.
 
IO - I've got a 2 1/2" lift in the springs and another 1/2" in the shackles. I dropped the tranny 1".

When I pulled everything apart, the bell crank studs and pivot bushings were shot. The pivot studs were worn about 1/2 way thru. So I guess I'll see what I can come up with to level them out. I guess it's either that or take the drop out off the tranny and go with a double cardon drive shaft.

Thanks, Bill
 
Billy I don't think you have to sweat the drive shaft angle a whole lot with a 2 1/2 " lift. I know I never did. In fact I would bring the Transmission back where it belongs. IMHO :cool:


billyocup said:
IO - I've got a 2 1/2" lift in the springs and another 1/2" in the shackles. I dropped the tranny 1".

When I pulled everything apart, the bell crank studs and pivot bushings were shot. The pivot studs were worn about 1/2 way thru. So I guess I'll see what I can come up with to level them out. I guess it's either that or take the drop out off the tranny and go with a double cardon drive shaft.

Thanks, Bill
Click to expand...
 
I think I would hold off until you get the body back on and put some weight on the springs.
That distance might change.
 
hagar said:
I think I would hold off until you get the body back on and put some weight on the springs.
That distance might change.
Click to expand...
I don't think so one side is bolted to the frame and the other to the motor which is also bolted to the frame so how is the weight of the body going to change anything.
 
Only thing that will change slightly with the body weight is the driveshaft angle.

Might think about putting a hydraulic clutch system in. You won't regrete it.
 
mtnwhlr said:
I don't think so one side is bolted to the frame and the other to the motor which is also bolted to the frame so how is the weight of the body going to change anything.
Click to expand...
Lifting the body has no affect on the clutch linkage between the engine and frame.

I'm betting that the kit did not come with the Transmission drop (did it?).

You should not need a Transmission drop with a 2.5" lift. Remove the Transmission spacer and your clutch linkage will be returned to factory specs.
 
My 73 had a four inch lift and no Transmission drop and the stock DS was fine.

I've changed a bunch of stuff and now have a hydro clutch but I actually liked how the bell crank worked. Real light pedal pressure. Never had it come off. Just run a heim joint on one end.

Id do like the other guys said and pull the Transmission drop; might just need to rotate the axle a bit.
 
CJ said:
Lifting the body has no affect on the clutch linkage between the engine and frame.

I'm betting that the kit did not come with the Transmission drop (did it?).

You should not need a Transmission drop with a 2.5" lift. Remove the Transmission spacer and your clutch linkage will be returned to factory specs.
Click to expand...

Since the lift was on the Jeep when I got it, I don't know exactly what came with the lift kit, but there was a Transmission drop of about 5/8" and wedges at the rear spring perches when I pulled everything apart. I haven't put the driveshaft in yet so I can check the angle, but it looks like it's still going to be more than 3 degrees (which I read was maximum?). I read another thread awhile back about determining the amount of lift in the springs and thought I measured it correctly, but maybe I've got more than 2 1/2" of lift. The tub is on the frame. The only things left that will add weight to the suspension are the seats and roll cage, so It should be pretty settled in.

I thought about a hydraulic clutch setup and maybe in the future, but right now I can't afford it and I'd like to get this thing operational.
 
That year CJ should have come with two little plates per side that went between the frame and Transmission crossmember. Combined they could be about 5/8", I never measured mine.

Did you put different motor mounts in or something? The more I think about it, the more wrong that looks. The two mounting points are both effectively on the frame; one actually is, and the other is one the engine which is bolted to the frame. The bell crank pin on the engine is closer to the motor mount than the Transmission crossmember so it seems like you would have to put a LOT of drop in there to lower the bell crank mount that much.

My 4" lift came with no Transmission drop, some wedges for the rear springs, and thats it. Still used the factory driveshaft. I never measured the actual driveline angle but you can run a single cardan u joint at up to 15* max. So if the driveshaft angle is 25* down, you'd need the pinion at least 10* up. Your driveshaft angle is probably more like 15* I did check my pinion angle before I did a rear axle swap, and those wedges that came with the lift put my pinion angle at 14* (which was technically way wrong but I had no vibration).

Id take a look at the motor mounts and or put the Transmission drop back to the factory one and see what it looks like then. Doing some math in my head and I'd guesstimate (holy :dung: spell check didn't flag that word) you'd have to drop the Transmission 2" to drop the bell crank pin 1". Thats what is making me think something is up with the motor mounts. Maybe you ordered new ones and they sent the wrong ones? I have the factory AMC 304 motor mounts in my garage if you want me to measure them for you to compare. How much did you drop the Transmission ?
 
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I compared my new motor mounts to the old ones and they are about the same thickness, so I don't think that's the issue. There were 2 plates between the frame and the crossmember, on each side, when I took it apart. The plates were marked "Rancho", so I'm assuming they came with the lift kit when the PO put it on. So, basically I've only dropped it about 3/8" from where it was. My understanding was that the yoke angles off 90* for the diff and the tc were supposed to be the same?

Anyway I'm trying to get everything measured up and make a sketch with all the angles to show where I'm at. Not sure If I'll get it done today, but will post it when I do.

My other concern which I discovered when I started measuring is the the center of the diff yoke doesn't line up with the center of the tc yoke. The center of the diff yoke is 11 3/4" off the frame from the right side. The center of the tc yoke is 2" farther to the left. Doesn't seem right to me. I checked the distance from the spring perches out to the brake backing plates and it was the same both sides. The engine and tranny are where they have to go in the mounts and the tranny crosmember. I'm kinda confused???
 
So here is a sketch of what I've got as far as angles with a 1" drop on the tranny and about a 6* wedge at the spring perch (I appologize for my CAD program, it's really meant for house plans). This isn't exact, but it's pretty close.

I keep looking back at Busadave's drawing that shows the driveline angle off the centerline of the yokes as 3*, so that's one concern. Then the diff yoke and the tc yoke not being in line side to side. And then the issue with the bell crank pins lining up.

Kind of a can of worms :confused:

Thanks for any suggestions - Bill
 
your axle is rotated up 15 deg.? interesting.

do me a favor and measure the distance from the ground to the center of the axle and the distance from the ground to the top of the frame body mount outrigger under the drivers feet. not the bottom of the body but the top of the frame.:cool:
 
IO - I've got 16 1/4" to center of axle (makes sense - 33" tires) and 24" from the ground to the top of the frame body mount outrigger.
 
IOPort51 said:
assuming that the 75 has the same characteristics an the later70s do, with these numbers I am suggesting that you have a 2 1/2 " lift. you may, with the body off, be close to 2 3/4" but I think that will change with the body weight.:cool:
Click to expand...

IO - That's what I figure. I ran a straight edge from front eye to rear eye on the springs and measured down to the top of the axle (read that somewhere) and came up with the same thing - 2 1/2 " of lift.
 
I had read this also but there was not enough information to back it up. this would seem to at least partially back it up.:D


billyocup said:
IO - That's what I figure. I ran a straight edge from front eye to rear eye on the springs and measured down to the top of the axle (read that somewhere) and came up with the same thing - 2 1/2 " of lift.
Click to expand...
 
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