Re: 4.0 -again

["Jim Blair" <carnuck@xxxxxxxxxxx>]

A: I had a carb hooked up on the Renix 4.0L I had in my '84 J10 temporarily 
(that never got finished enough to drive far due to UPS losing my spring 
over axle steering parts and I had to convert my '86 Comanche to 4x4 for the 
big Ouray trip) I'm about to install another 4.0L into my '84 J10 and can 
give pointers. Brake boosters are an issue in the J10 (going to Hydroboost 
instead) but the rest was pretty straightforward. Knock sensor required a 
bit of figeting around. I used the PS pump and serpentine belt setup that 
came with the first 4.0l (probably will again) with AC Delco alt in place of 
the Jeep one.


From: farna@xxxxxxx
Subject: Re: 4.0  -again
To: mail@xxxxxxxxxxxx
Message-ID: <ADVANCES62x1kLwxTQT0000004f@xxxxxxxxxxxxxxxxxxxxxxx>

1. The intake and exhaust manifolds aren't normally used. You *might* be 
able to keep them by making a spacer where the intake and exhaust manifolds 
bolt together. Most of the time the 4.0L exhaust is used since it's much 
lighter and better flowing, and the bottom of the intake is just blocked 
off. The only problem with this is cold weather driving is highly 
affected -- takes a while to get the engine up to operating temps. You'll 
also have to drill and tap the 4.0L head for a small machine screw (about a 
#6) just above the pin that the intake rests on for alignment. With the head 
off and on its side, align and mark where the screw needs to be then drill 
and tap.

2. Keeping the 199 pulleys will be a problem. The 199 water pump should fit, 
so that's not a big deal (remember, serpentine belt pumps run backwards in 
relation to V-belt pumps). Mounting points for accessories changed in 1974, 
so you will have to adjust/modify/fabricate brackets to fit.

3. The biggest hurdle is the transmission. If you have an auto it can't be 
used. The bolt pattern for the six changed in 1972 -- 1971 and earlier have 
a smaller diameter bell. You can use an old model manual trans by getting a 
1979-83 bell housing. You'll need the 79-83 manual trans bearing retainer 
too. Either drill the old trans for the new retainer or the retainer for the 
trans. The auto is air cooled or I'd say get a model 40 V-8 bell -- the 
model 37 trans should fit it, but the model 35 won't. Best to stick with the 
Jeep auto trans or a newer model 998. The Jeep AW4 auto is electonic, but 
you can easily and cheaply make a manual controller -- I did. Put it in 
drive the turn a switch to change gears -- semi-auto. It's a four speed auto 
too (0.70 OD).

4. As far as engine mounts that's easy -- the side plates from the 199 bolt 
right onto the 4.0L.

5. If you're going to the trouble of installing a 4.0L, you really should 
use the EFI. It's more reliable, powerful, and fuel efficient. It can be 
made to look almost stock. I have an open round air filter on mine, and most 
people see that and don't eve notice the injectors unless they look close! 
For a pic of my engine go to 

http://groups.msn.com/amcsforever/farnasramblers.msnw.