Installing a crank position sensor set up on stock trans?

[shanebo]

  I am doing the 4.0 EFI conversion. one of my many obsticles  is going to be installing the crank position sensor that does not exist on our ealges. I am not sure how to modify the stock Eagle trans to take the jeeps crank sensor....any help greatly appreciated.

Thanx
Shane

[amcinstaller]

drill, cut, make small bracket. others have also just drilled a small hole and plugged the sensor into the hole

[eaglefreek]

You will need the appropriate flexplate that matches the computer you will be using. If using an OBD1 computer and using an auto transmission you would need to use a flexplate and starter from a 91-95 Wranger because they use basically the same transmission as the Eagle. Another option would be to use a Wranger TF999 transmission that has the hole for the cps. If manual, you'll have to search the net about the proper flywheel.

[philotomy]

I believe mine is on the front bottom of my crank pulley,but it was part of that Hesco kit, a special pulley with that built into it.stock trans

[philotomy]

here's mine it has a plate bolted to the oil pan for support,its a bit dirty right now thanks to the rad quitting on me and I believe it has a special crank pulley/harmonic balancer just for this application

[Jurjen]

Here is a picture from Novak adaptors:
http://www.novak-adapt.com/knowledge/ford_to_amc.htm

[captspillane]

The Hesco kit is very expensive and very fragile. Hesco even suggests you buy their trail kit, which comes with an extra fuel pump and two extra CPS sensors. Its common to have them bumped or jarred, and then the engine won't run. It's worth trying to modify your old transmission.

Its been done two different ways. One is the square CPS sensor like a 1992 Jeep Cheroke would have. Another is a 1/2 inch round CPS sensor like a wrangler would have. I purchased two of the round version to try this. It should work slick in the sense that you just need to drill a hole. There are two externally identical round ones to choose from, you have to get the earlier version so that it accepts the correct voltage. OBD1 and OBD2 use different operating voltages.

Don't use an AW4 flexplate. Its 4mm different than the TF727 flexplate. The "32RH" is another name for the TF727, after they started putting the CPS sensor in. The Wrangler 32RH flexplate will look identical to your old Eagle one except it will have a ring around it with holes in it to work with the CPS sensor.

[philotomy]

hmm no problem here with mine and ran fine for 3 1/2 yrs in the snow and dirt roads,I'd check into the  link posted by Jurgen if you're not going with a "kit".

[eaglefreek]

Not that it matters, but the original post was from over a year ago. 

[philotomy]

yeah i had sent Shanebo all my conversion paperwork last year I believe in hopes that it would be of some help,but mine is the whole (expensive kit) while I think Shanebo is doing it with the Rambler mentality

[carnuck]

The Hesco kit is very expensive and very fragile. Hesco even suggests you buy their trail kit, which comes with an extra fuel pump and two extra CPS sensors. Its common to have them bumped or jarred, and then the engine won't run. It's worth trying to modify your old transmission.

Its been done two different ways. One is the square CPS sensor like a 1992 Jeep Cheroke would have. Another is a 1/2 inch round CPS sensor like a wrangler would have. I purchased two of the round version to try this. It should work slick in the sense that you just need to drill a hole. There are two externally identical round ones to choose from, you have to get the earlier version so that it accepts the correct voltage. OBD1 and OBD2 use different operating voltages.

Don't use an AW4 flexplate. Its 4mm different than the TF727 flexplate. The "32RH" is another name for the TF727, after they started putting the CPS sensor in. The Wrangler 32RH flexplate will look identical to your old Eagle one except it will have a ring around it with holes in it to work with the CPS sensor.

999 is 32RH and 727 is 36RH (Grand Cherokee 4 speed auto on 4.0L is 42RE, etc)

[carguy87]

I used the 42RE flexplate off the 4.0L from a 95' Grand Cherokee.  I also used the corresponding CPS that has one tab for a mounting bolt.  I cut a hole in the bell housing and made a bracket that crosses the two bolt holes and is held in place using the bell housing to engine block mounting bolts.  Then it is simply slid down into place, and bolted to the bracket.  Been like that for a year now as my daily driver in Michigan.

[captspillane]

I understand this is a very old post being revived. My main motivation for writing this reply is that I recently almost tried using a AW4 flexplate with a torqueflite transmission. I would have blown up the transmission. Thankfully I came across a post on a forum about it before I made that same mistake. I want this information to be readily available in the future.

999 is 32RH and 727 is 36RH (Grand Cherokee 4 speed auto on 4.0L is 42RE, etc)

To be more precise, there are four types of flexplates available for AMC Engines.

1) The automatic transmissions original to the AMC Eagle were the hydraulically controlled “Torqueflite” transmissions. These transmissions for a short time were produced by Chrysler with CPS rings on them before the newer electronically controlled four speed transmissions appeared. TF904, TF998, TF999, and TF727 all use the same flexplate without the CPS Ring. The exact same transmission was still produced after Chrysler changed their naming conventions. Early 90’s Wranglers had the exact same transmission as our Eagle does except for a very minor internal difference (TF998 vs TF999) and the addition of a CPS signal at the edge of the bellhousing. The CPS needed a ring with holes added to the flexplate. They named that “32RH” to mean it is a three speed, strength rating of 2, “H” hydraulically controlled transmission. If you find a rare 32RH transmission it is a direct bolt in solution with no modifications needed and no $350 Hesco CPS relocation kit required. The TF727 with its larger planetaries designed for truck applications became the “36RH” to mean three speed, strength rating of 6, “H” hydraulically controlled transmission. Unfortunately there was never a 36RH with CPS holes produced that will bolt up to an AMC Engine. All 36RH transmissions have a Chrysler bolt pattern. The only Jeeps to receive that transmission were the Grand Cherokees with Chrysler V8 engines.

2) AW4 flexplate. This flexplate is almost identical to the torqueflite version, but not quite. All Jeep XJ Cherokees had the AW4 four speed automatic transmission. I have read stories of people taking the AW4 flexplate and putting it in front of a 32RH transmission. It bolted together fine and the vehicle even drove for about 50 miles without signs of an issue. After a short time period, however, the 4 mm difference in backspacing caused pressure to destroy the input shaft of the transmission along with mortally damaging the torque converter. It looks like it works but it doesn’t.

3) 42RE flexplate. This flexplate may or may not be identical to the torqueflite transmissions. The modern Chrysler four speeds were designed using knowledge from the tried and true torqueflite transmissions Chrysler was already producing for decades. The new electronic four speeds do not look at all the same and do not share any compatible internal or external parts as the older hydraulic three speeds, but I’ve seen conflicting reports of them using the exact same flexplate. “Carguy87” just stated in the last post that he successfully used this flexplate with the TF998 and I believe him. The 42RE transmissions are light duty equivalents to the TF998. A stronger 46RE equivalent to a TF747 is not available for AMC Engines. The 42RE is several inches longer and don’t fit well under an Eagle. In stock form they are not nearly as strong as a TF727. In the aftermarket, however, a 42RE can be rebuilt using the rear overdrive assembly from a Chrysler 46RE or even the stronger 47RE found behind Cummin’s Diesel engines. Several people specialize in making the AMC 42RE as strong as a TF727 or 46RE.

In truth, the biggest complaint against the 42RE is that it has some very strong components mixed with weak components. The weak components make it just as weak as an AW4 but the inertia of the strong components make it lose fuel mileage in comparison to the AW4. The AW4 is better in stock form but the 42RE has greater potential. I personally wish to use the AW4 behind my 6 cylinder motors and I wish to use the modified 42RE behind an AMC V8 in the future.

4) TH400 flexplate. This flexplate is more Chevy than Chrysler. It was used in Full Size Jeeps and CJ7’s with a special casting of the TH400. The TH400 is a three speed hydraulically controlled GM transmission that is exactly as strong as the Chrysler TF727. Internally it’s the same as the Chevy TH400 transmission but externally the output is rotated several degrees, the output shaft is crazy long, and the bellhousing bolts to AMC engines only. An AMC TH400 is often a poor choice of transmission because of the length and limited transfer case options, but this flexplate can be used to adapt the 700R4 four speed electronically controlled Chevy transmission to an AMC Engine. The 700R4, unlike the TH400, is sometimes compatible with the New Process transfer cases suitable for our Eagles. Of course every transmission can be adapted successfully, but the adaptor cost is prohibitive. A rare version of the 700R4 came from the factory mated to the 6 bolt New Process pattern. I will use a 700R4 as an overdriven automatic strong enough to live behind a built AMC V8 if the modification of the 42RE is inadequate.

[captspillane]

I also used the corresponding CPS that has one tab for a mounting bolt. 

Its a pleasure to hear from someone with first hand experience. Your CPS was round, about 1/2" diameter, with a single tab for a mounting bolt, correct? Do you have pictures of this installation?

Thank you for the information you have. I'm about to attempt this with a TF727 with that style of CPS. I've only seen pictures of the square, two tab style so far.

[carnuck]

Somewhere in my piles of stuff I have a 999 trans case from a '00 Wrangler with 4.0L I was going to build it with Eagle internals (valve body was bad), but never got around to it