Factory balancer mount CPS???

[farna]

A well known and respectable poster on the AMC-List and some of the Jeep boards has stated that he has seen a FACTORY STOCK balancer mounted CPS on a 1994 4.0L. He didn't state what model (XJ or Wrangler). I suspect what he saw was a HESCO unit that had been installed in place of the factory CPS, probably because the factory bell location is hard to get to in the field. I know some Jeepers do this after having one go out -- real easy to replace with the HESCO front mount. I see no reason for the factory to EVER have used a front mount CPS. Has anyone seen one that they can verify is factory? Maybe an early Wrangler?

I have heard that the HESCO balancer can slip, which cause timing problems. Could be a quality control problem with the balancer supplier.

It wouldn't be hard to make a bolt-on tone ring for a sensor. Has anyone done this yet?

[5-90]

Factory? New one on me!

What I'd like to see is a unit made rather like the Fluidampr (enclosed inertia ring, solid outer case. Inertia ring held with a high-shear viscous silicone, or something like that...) with the trigger notches machined into the outer case. Then, the timing CAN'T slip!

[SilverXJ]

Factory? New one on me!

x2 Never saw it.

Fluidampr (enclosed inertia ring, solid outer case. Inertia ring held with a high-shear viscous silicone, or something like that...) with the trigger notches machined into the outer case. Then, the timing CAN'T slip!

Wouldn't go near a fluid. Heard of too many cranks breaking with those. ATI has something similar w/o the fluid part. The outter housing it bolted to the hub.

[HowieH]

Long ago and far away : Old thread, I know, but here's a story :
I purchased a harmonic balancer for a front mount CPS a few years ago from 4 Wheel Drive Hardware. It was machined to trigger the ( added and located) new, OEM hall effect driven sensor. The machined spacing on the new balancer, match the relative trigger point angular spacings that are on the , ( un-balanced ), trigger ring bolted to the flywheel on the newer 4.0L engine's fly wheels. ( no "add-on plate" to slip timing ).
This gives one some options as to the angular position you can mount the CPS. Each group of machined slots is non dedicated, so that gives you even more options for locating your custom fabricated CPS mounting bracket. Yup, best to make your own bracket, make it with an adjusting slot for fine tuning. My bracket is bolted to two of my oil pan bolts.
The machined harmonic balancer looks factory.
They used to be available for v-belt or serpentine belt

Ah ...... why all this you might ask ?
Well, the balancer was first installed on a 4.2L engine that received a welded and "decked" 4.0L head in order to fuel inject the 4.2L engine, eliminating the original and highly cursed BBD Carburetor.
I then could keep the 1983 bellhousing, unmodified, and the T176, 4 spd manual trans.
For the electrical, I recommend the Mitchell Manual's Schematics for both objective and donor vehicles, taped to the wall and get a large box of colored pencils.
The new, machined 4.0L multi port injected head worked very well.
Then I learned about Strokers. Eureka !! Now I will be building another stroker.

So ....
Interestingly some of the first Bosch multi port fuel injection systems fired all injectors at the same time.
TBI systems act like nothing more than an electronically controlled carburetor. This leads me to ask : IF, and IF the function of the CPS is solely to indirectly generate pulses for the injectors, why is timing so important anyway ? Now, I want another experiment !