very nice

 

Great to hear you got it back on the road! I think you might have the same 410 gears that I do, we both had the same engine/trans combo. You should try some taller tires, are you still running the 215's?

 

Yep, factory rims and tires. I need to transplant the tach out of the Benz gauge cluster into the Jeep so I can see what kind of RPM's i'm turning now.

John

 

My plan as well.

 

The 4.10 gears were only installed from the factory with the 2.8 V6 and the manual transmission (AX-5), and the 2.5L 4cyl with the A904 automatic (which is what I intentionally hunted down for my project).

If you got 4.10 gears in an XJ with the 2.8L V6 and A904 automatic, someone had to have regeared it. That engine/tranny combo only came from the factory with 3.55 gears - unless you ordered the "towing" package - in which case the factory installed 3.73 gears. Of course there are a wide range of aftermarket gears available (4.56, 4.88, 4.92, and 5.13) and tens of thousands of Jeeps have been regeared for bigger tires.

You wouldn't happen to have hit the Jeep lottery and got one with the Holy Grail of all XJ options too, would you? Of course I'm talking about the D44 rear axle...

BTW, one of the BEST things about the OM617 is that one in good shape can run 4000-4500 RPMs all day long, and even endure being occasionally run clear up to 5000 RPMs. Most older diesels top out at around 3500-4000 RPMs and having that extra 500-1000 RPMs worth of "working range" is really a BIG benefit in a passenger vehicle.

 

I wired up a toggle switch and relay for the electric fan. I have not been running a fan at all yet, the 4.0 radiator is pretty efficient. The fan I used is the electric "pusher" fan that came off the 300SD. I installed it backwards behind the radiator, it pulls quite a bit of air! I also wired a toggle for the "afterglow". It cuts the power to the "purple" wire coming off the glow plug relay. If the ambient temp is low, I can turn the switch off, and the glow plugs will stay on after the engine starts until the relay times out. It helps quite a bit. I installed a tailpipe too, I bought one for a 4.0 Jeep, it's 2 1/8" ID. Plenty big for the 617. I removed the factory tach and was going to install the tach from the Benz cluster. The Benz tach won't fit without a ton of butchering and fabricating, so I put the Jeep tach back in. I am going to try and figure out how to make the Jeep tach work with the sensor/amplifier for the 617. I still need to wire up yet another switch for the TC lockup. I cut a hole in the hood where the engine was hitting the hood. I found this old Mr Gasket foam air cleaner lying around, so I bolted it to the hood. It's my redneck hood scoop!!! Here are a couple pics. I have gone 120 miles so far and used 1/4 tank of fuel.

 

Have you thought about getting one of those adapters that senses the rotating magnetic field of your alternator and creates tach signal from it? They can be calibrated to adjust for the difference between the size of the crank pulley and alternator pulley. Probably the route I'll end up going - they're only $40-$60 on eBay.

Just a thought...

 

Hi John, how did you hook your throttle and TV cable? I have read that it is extremely important to get it correct. All I have read references carb installs, so the measurements don't seem to work with the benz linkage. The benz TV lever doesn't move enough according to the 700r4 specs. Any ideas?

 

Here are a couple of pics of my setup. I used the carb TV bracket off the 2.8 and cut it smaller. I drilled new holes in it so it would mount properly to the top of the engine. The TV cable has a "ratcheting" adjustment. You normally push it all the way in and then push the accelerator all the way to the floor to set it. The TV cable should be at full extension with the engine at WOT. The angle of opening is critical too, I tried to get mine as close to a gasser setup as I could (a smooth straight pull on the cable). The TV cable on the 2.8 700R4 was too short to reach where I mounted my bracket. I used a TV cable from a 200R4 I already had. It's originally for a 1985 Cadillac Fleetwood with a 4.1 engine. I thought about taking mine to a tranny shop and have them check the line pressure and what not to make sure I adjusted it right. My trans shifts right at 15, 30, 40-50, depending on acceleration, so I must have it pretty good. I had a homemade TV bracket on my Caddy hearse too, I never had a problem. I just made sure the cable was at full travel at WOT.
Hope this helps!!

John

 

Here is a link that explains it in great detail.


GM TV Cable Adjustment Instructions