I recently picked up a 87 cherokee as a project for my son and myself. The story goes that the original motor was running but had a knock so the previous owner picked up a used motor and swapped it out. During the swap the previous owner lost motivation so the jeep set for some undetermined time. He tried to finish up the swap but realized the motor was now locked up. This is the point where I picked up the vehicle.

Once I had it home I poured some marvel mystery oil into the cylinders and let it set for a couple days. With about 10 buckets of elbow grease I finally got the motor freed up and spinning over. Not all of the wiring harness was connected along with a few other things here and there but I put back everything that I could. The only thing I that is not back on is the serpentine belt, fan blade and the cover between the engine and transmission.

I am trying to get the motor to fire and see if I can get it to run but I can't seem to get any spark. I have done the following so far:

1. new spark plugs
2. new rotor and cap
3. check coil and it shows good
4. to the control model to local parts store and it checked good.
5. Verified the crank position sensor was connected

Hopefully some of the cherokee experts can guide me in the right direction. Appreciate everyone's help.

 

I know stupid questions but is it getting fuel? has spark?

 

I haven't checked the fuel yet but it is not getting any spark. I am trying to get the spark problem fixed first.

 

you say the bellhousing is not there? the crankshaft position sensor mounts to the bellhousing that is what sends the signal for triggering spark

 

He's talking about the inspection plate between trans and engine.

What year is the donor motor? Is the 87's flywheel and CPS installed?

 

He says the CPS is connected (#5) but that seems the culprit as long as you know the coil and other ign. parts are good. It won't spark unless it can count the teeth on the flywheel.

 

Im going to have to agree swap out the cps just because it is pluged in doesnt mean its working. Exspecially if it has set for a long time

 

sorry its beena long week Im reading but its not sinking in I guess, need start paying more attention.

 

I am not sure what year the donor motor is. Are there numbers on the engine somewhere to verify the year?

I am not sure on the flywheel or the CPS. I can see on the flywheel has some notches for the CPS to read.

I guess I will change out the CPS. How critical is the gap on the CPS. I have a Haynes manual but it doesn't really go into detail. Is there a voltage reading that can be checked on the connector that plugs into the CPS?