No Start after lots of work

[UNL1MTD]

I know there is a 'No Start' thread every day or so, I figured it wouldn't be a big deal if I add mine.

 

I have an '87 4.0L 2wd MJ with a BA10. I just got done buttoning up all of my work and tried to turn the MJ over, but it wouldn't start. The starter cranks, just doesn't catch. It'll crank for 5-7 seconds then abruptly stop cranking, with the lights dimming briefly. If I hold the key, it will just repeat. I pumped the gas once and that resulted in a backfire. On the first try it wouldn't abruptly stop, it would just crank, I let it go for about 15 seconds. Normally the MJ has about a 5-7 second crank cycle before starting, definitely not out of the ordinary for it sit there and crank a bit before firing up.

 

The MJ hasn't been turned over since Mid March. I've had it parked and slowly been doing some work centered around the RMS replacement. The following is a list of work done since its last been started.

 

Engine Related Work

-Starter Removed and Replaced with a Reman Unit

-Oil Pan removed and replaced

-Oil Pump/Screen removed and replaced with a Reman Unit

-RMS removed and replaced

-Adjusted the serp belt

-Distributor removed and replaced with a Reman Unit

-Crank was turned with dizzy out during RMS install

-Main bearing caps were loosened during RMS install (retorque with torque wrench, double checked)

-Primed Reman Oil pump with a screwdriver in a drill

Non-Engine Related Work

-Front Soft/Hard brakelines replaced

-MC/Booster removed/replaced for access to prop valve

-Brakes bled

-Interior work on window trim

-Front steering and suspension removed & replaced to gain access for RMS install

 

I really thought I might have goobered up the Dizzy install because I wanted to prime the new oil pump so I spun it with a drill and screw driver. So I double checked it to be in the Number 1 position by doing the whole remove the spark plug and feel for a rush of air thing, then reinstalled. After that did nothing, I went so far as to replace the Reman Dizzy with the old Dizzy, which worked but was leaking oil inside of the dizzy. That also had no effect. I can use the started to bump the dizzy, so I know everything is spinning. Then I put a battery tendered on the battery and called it a night. I plan on using my spark tester tomorrow to see if I'm getting a spark from the coil, thats about the only trick up my sleeve at this point.

 

I have two inclinations at this point. 1) I still have the timing messed up and I need to redo the Top Dead Center thing. Further instruction there would be helpful. 2) Somehow the CPS went bad during its time off and sitting in a climate controled garage. I'm open to ideas, would really like to get the MJ back on the road.

 

:hmm:

 

Thanks,

 

Sean

[Geonovast]

My bet's on the dizzy being off.

 

Another possibility is spark plug wires are in the wrong place. I had accidentally once(non-marked cap, and my brother told me over the phone where his were), had the plug wires rotated one terminal. It would crank for a few seconds, then the ECU would cut power to the starter cause it knew something was very, very wrong.

[Harper]

:agree: If I read your comment right, it sounds like the timing is advanced too far (like way too far) causing (1) a momentary stoppage during crank, and (2) a backfire with partial throttle. Recheck the ign timing......

[UNL1MTD]

My bet's on the dizzy being off.

 

Another possibility is spark plug wires are in the wrong place. I had accidentally once(non-marked cap, and my brother told me over the phone where his were), had the plug wires rotated one terminal. It would crank for a few seconds, then the ECU would cut power to the starter cause it knew something was very, very wrong.

 

Whats the correct way to readjust the dizzy to get it checked out? I have always been careful in the past about removing it only at the #1 position, but during this lenghty down time, I got careless. I followed what I thought was the way to do it, but I might be missing something.

 

For the plug wires, I'll triple check. When I reinstalled I based it off of the screw positions of the dizzy cap and the haynes manual. so

.....6

..3......2

0.........0

..5.....4

.....1

[UNL1MTD]

:agree: If I read your comment right, it sounds like the timing is advanced too far (like way too far) causing (1) a momentary stoppage during crank, and (2) a backfire with partial throttle. Recheck the ign timing......

 

 

How do I check/fix this?

[Harper]

Well, you've got an aftermarket distributor on there, so, I'm not sure how it's gonna look, but I would try the simple thing first. If you're sure you got the wires in the right order, loosen the dizzy and turn just a little clockwise. Try to crank it again. If it doesn;t fire up in 3-4 seconds, then turn a little more. If you have a timing light, and a remote starter or a helper, then use that. If none of that works, then turn the engine until you have #1 cyl at tdc, both valves closed, and take the cap off the dizzy and see how close your rotor is to #1 wire. This should get you on the right track.

[Harper]

Jusr re-read your #1 post and guess it's a reman dist. So #1 wire should be farthest fron the block, with cap screws between #4 and #1, and also between #3 and #6. Dizzy turns CW.

[Geonovast]

:agree:

 

Dunno why I didn't think of it, but you said you put the dizzy in at #1 TDC. Are you sure you got it on the correct stroke?

[UNL1MTD]

:agree:

 

Dunno why I didn't think of it, but you said you put the dizzy in at #1 TDC. Are you sure you got it on the correct stroke?

 

 

I had my wife helping me with her hand over the plug hole when I was spinning the crank. She said it gushed air. I dropped in the dizzy and it was at the 1 position. I thought if it was on the exhaust stroke the rotor would be at the 6 position?

 

It is just a remanufacturered dizzy and the stock one is currently reinstalled during this trouble shooting.

[UNL1MTD]

Jusr re-read your #1 post and guess it's a reman dist. So #1 wire should be farthest fron the block, with cap screws between #4 and #1, and also between #3 and #6. Dizzy turns CW.

 

 

ok, this is good to know, looks like I have it with the cap screws between 4 and 2 / 3 and 5.

 

edit -

 

looking back on old pictures, its been this way forever, I'll still double check, but I'm thinking it might not be the wires.

[Harper]

The cap screws don't necessarily have to be as i described, that's the way the factory has 'em set up, but if they're in the right order, and you have the timing right, it won't matter. Some caps have the wire numbers on the cap.....in any case, when your wife said the plug hole gushed air and you put the dizzy in with rotor at #1, was the crank also lined up with the timing marks, and did you adjust the dist after you put it in, to be sure the rotor was still at #1? I ask, because when you put the dizzy back in , the gear causes the rotor to turn quite a bit.

[UNL1MTD]

when your wife said the plug hole gushed air and you put the dizzy in with rotor at #1, was the crank also lined up with the timing marks, and did you adjust the dist after you put it in, to be sure the rotor was still at #1? I ask, because when you put the dizzy back in , the gear causes the rotor to turn quite a bit.

 

 

No, I wasn't aware of the timing marks. I doubt there is a chance I got it right just by stopping when I did. This is definitely something to check/fix. Where are the marks located?

 

I'm not really able to do much adjustment to the dizzy when it goes back in. Where it is bolted down the slot is only so big and the housing rotors a max of 1/8th of an inch. Once the dizzy seats in the oil pump I can't really move the rotor either especially since it's mesh up with the gear on the crank. I could be missing something obvious here too.

[Geonovast]

I'm a little lost here. The cap screws have to be in the same place on every cap. An aftermarket company can't just decide to move the terminals.

 

There's a timing mark on the harmonic balancer, and it lines up with marks on a tab on the timing cover. This may not be entirely accurate, however, since it is possible for the outer piece of the balancer to turn on the rubber isolator, causing the mark to be off. Just an FYI.

 

Also, the dist is run off the cam, not the crank. I'm sure that's what you meant. :thumbsup:

[Harper]

"I'm a little lost here. The cap screws have to be in the same place on every cap. An aftermarket company can't just decide to move the terminals." -Geonovast

 

I agree it's not the best idea to, say, install all the wires one distributor terminal too far one direction or the other, but the terminals on the 4.0 are 60 degrees apart, and as long as they're in the correct order, the dizzy can theoretically be turned far enough one way or the other to correctly time it. In practice, however this might not be the case, because interference with other components might preclude turning the dizzy far enough for correct timing. If it were me, I'd pull the wires off the cap, pull the dizzy, set the engine at TDC (again, making sure you're on the right stroke) using the marks on the harmonic balancer/engine block to start with, put the dizzy back in with #1 at 6 o'clock (as seen when you lean over the fender) and the rotor at approx 4 o'clock. As you mesh the dizzy gear with the cam drive gear, the rotor will turn to around 5 o'clock by the time the dizzy is seated. And yes, I'd recommend that you put the wires on as intended, with the cap screws between 4 & 1 and 3 & 6. Just because any other arrangement is workable, doesn't mean it's advisable. At that point, you should be able to crank 'er up.

[UNL1MTD]

I'm a little lost here. The cap screws have to be in the same place on every cap. An aftermarket company can't just decide to move the terminals.

 

There's a timing mark on the harmonic balancer, and it lines up with marks on a tab on the timing cover. This may not be entirely accurate, however, since it is possible for the outer piece of the balancer to turn on the rubber isolator, causing the mark to be off. Just an FYI.

 

Also, the dist is run off the cam, not the crank. I'm sure that's what you meant. :thumbsup:

 

 

You caught me, I'm a complete engine noob.

 

I'm going out and going to give this another go. Hopefully I have some success to report back. I appreciate all the help up to this point.

[UNL1MTD]

If it were me, I'd pull the wires off the cap, pull the dizzy, set the engine at TDC (again, making sure you're on the right stroke) using the marks on the harmonic balancer/engine block to start with, put the dizzy back in with #1 at 6 o'clock (as seen when you lean over the fender) and the rotor at approx 4 o'clock. As you mesh the dizzy gear with the cam drive gear, the rotor will turn to around 5 o'clock by the time the dizzy is seated. And yes, I'd recommend that you put the wires on as intended, with the cap screws between 4 & 1 and 3 & 6. Just because any other arrangement is workable, doesn't mean it's advisable. At that point, you should be able to crank 'er up.

 

 

:agree:

 

 

:banana:

 

Started up like a champ after correctly setting the number 1 to TDC. It took about 10 minutes and now runs pretty well. Best part being is NO LEAKs, atleast for the time being. I did end up leaving the old dizzy in, I plan to replace it down the road after I see how it runs. Next step is inspection. FWIW my plug wires were installed correctly, for whatever reason the cap screws are between 4 & 2 / 5 & 3, however 1 is still at the 5 o'clock. Thanks again for the good advice.

 

:cheers: