4.0 Swap w/Pictures
ThisGuyUKnow
Full Time Jeeper
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- Location
- Harleysville, PA
- Vehicle(s)
- 1986 CJ7 Laredo 4.0,Nv3550,D300 Twin Stick,AMC20 3.31, 31 BFG
Honda vtx1800c
A couple more pics of the Clutch linkageI kinda skimped on the pictures but this weekend I went ahead and installed the cluch linkage.
In the light of making this as stock looking as possible, the clutch setup became sort of an issue. The CJ tub is stamped for the hydraulic MC used in 4 cyl Cjs. Since the YJs used a hydraulic clutch, it made sense to go ahead and swap out out the pedal assembly for a YJ setup.
I have known that I was going to use a NV3550 in this Jeep since square one. So when I bought the Jeep I asked Ed (onlyinajeepCJ) whom I bought the Jeep from to go ahead and predrill the fire wall for all the extra stuff on the YJ.
There are two generations of YJ pedal assemblies. the 87-90 assemblies still used the same MC as the 4cyl cjs. That means that the MC will cleanly fit into the pre stamped portion of the fire wall. 91+ went to a different MC that has a wider mounting footprint. So if you use that it would look awkward, I have done this before with my previous CJ and the result is not that great.
The rub is that the pre 91 MCs were not used with external slaved transmisions and the fitting on the MC is different between the years. Because of this, I could not reuse the preformed hydraulic linkage from a YJ. I had to go to a hose shop and have them make me a hose that had the screw in style fitting for the MC and the push in style for the slave. Fairly easy process, I walked in and in 30 minutes walked out with a hose. Most of the time was used explaining what I wanted and finding a fitting that worked with the firewall constrictions.
I assembled the hose assembly and bled it with DOT3. Technically these are prebled in factory and you supposedly cant bleed them but the linkage is self bleeding. If you actuate the slave it will push all the air out of slave .
The biggest PITA was the removal and reinstall of the pedal assembly, I'd recommend completely removing the dash which I didnt do. Once it was in, everything bolts up in the same spots as the CJ assembly. The only different is that the pedal pivot has a bracket on the end of it that reinforces the firewall around the MC and has studs to bolt the MC to. There is also an extra support rod that runs off the left side of the assembly and bolts through the fire wall close to the fender.

