1996 Cherokee 4.0 I6 timing mark. ??

Hi. I'm new to the group. My neighbor has a 96 Cherokee 4.0 I6 MPFI. The distributor holddown bolt came out and it spit the distributor out. He has purchased a new distributor (it bent the shaft on his old one) and has asked me to help him install the new one.

He says the engine has no ignition timing mark. That being the case, how do I position the engine to get the rotor button aligned with the #1 tower at DTC on #1 cylinder??

I am a fairly experienced mechanic on Dodges (and Studebakers :) but am short on practical knowledge on jeeps.

Just trying to help out a neighbor in distress.

Thx in advance.

"Leroy"

Reply to
Leroy
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1.. Remove the No. 1 cylinder spark plug. Turn the engine using a socket wrench on the large bolt on the front of the crankshaft pulley. Place a finger near the No. 1 spark plug hole and turn the crankshaft until the piston reaches Top Dead Center (TDC). As the engine approaches TDC, you will feel air being expelled by the No. 1 cylinder. If the position is not being met, turn the engine another full turn (360 degree). Once the engine's position is correct, install the spark plug. 2.. Using a flat-bladed screwdriver, in the distributor hole, rotate the oil pump gear so that the slot in the oil pump shaft is in the correct position. 3.. With the distributor cap removed, install the distributor so that the rotor is positioned correctly. Insure that the distributor is fully seated against the cylinder block. If not, remove the distributor and perform the entire procedure again. 4.. Tighten the hold-down bolt to 17 ft. lbs. (23 Nm). 5.. Install distributor cap and ignition wires. Insure that the wires are routed correctly before attempting to start engine.
Reply to
Mike

It's on the timing cover where you'd expect it to be.

Reply to
bllsht

The rotor should be pointing directly away from the engine block for #1 also.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06
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Reply to
Mike Romain

But as there are helical gears on the bottom you have to off-set the rotor when you first guide it in. To get proper placement may take a couple trys to get it into the right combination of teeth so the rotor is pointing exactly at the number one terminal..

Reply to
billy ray

Reply to
bllsht

If it was there, we (3 of us) never found it.

Anyway, it was a no-brainer.

The A/C compressor was in the way on #1 so I timed it off of #6 plug hole and #6 tower on the opposite side of the distributor. Got #6 on the compression stroke by the "thumb in the hole" method then ran a screwdriver down the plug hole and could feel the piston movement when the crank was being turned with a socket (not the starter!!!). Got #6 as close to DTC as possible by feeling the piston stop at top . Set the rotor button to where the trail edge had just cleared the #6 tower and locked it down.

Presto. It ran like a Jeep! :)

Took about 20 minutes and I now have an extra case of beer-- and a happy neighbor.

A great big old Thank you to all who responded.

"Leroy"

Reply to
Leroy

Thanks for the follow up!

You and your 2 friends are correct about there being no timing mark on the 4.0 engines. I own 2 4.0's.

I just saw bullshit's photo over on alt.binaries.pictures.autos.4x4 and it is bullshit just like his posting name. He has shown a photo of what appears to be a 4.2 engine with it's V-belt pulleys and timing mark.

He is a hard person to follow, sometimes his advise is right on, other times it is complete bullshit.

The 4.0 does not have adjustable timing, the distributor fits a notch so there is no need for anything above a TDC mark.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06
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(More Off Road album links at bottom of the view page)
Reply to
Mike Romain

There he is, once again proudly displaying his ignorance!

That picture was the only one I could find, and it's not a 4.0L, but it was meant to indicate loacation, and that's what it does. It may not look exactly the same, and it's hard to see with the serpentine belt in the way, but it is there whether YOU can see it or not.

Unlike you, I only post when I'm sure I'm right on. You need to go take a closer look at your Jeeps. Maybe find a good mechanic to point it out to you.

Or, ask DougW. He will tell you it's there.

The notch locks the housing in. It doesn't, however, insure that the rotor will be pointing in the right direction. You need #1 at TDC to install a distributor correctly. The OP found a way around it, but the marks are there if you need them.

In fact, around 1988, they issued a TSB that dealt with a crossfire condition caused by rotor misalignment. The fix was to use the timing mark on to put #1 at TDC, then cut the notch off the distributor housing so it could be rotated to properly align the rotor with the terminal in the cap.

The mark is there, it always has been, and was still there on the last

4.0L used by Jeep.

Reply to
bllsht

Yep.

Hard to see though. It's hiding below the water pump.

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Reply to
DougW

Guys .. Hey... I believe you (sounds lke some threads in the Dodge group .. :). After looking the situation over, I didn't need the mark, anyway.

Bllsht's post: "The trailing edge of the rotor should be just PAST the #1 terminal at TDC."

That post saved the day for me. When I put it in the first time I centered the tower and it ran like crap. I thought I remembered about the trailing edge .. re-checked the posts.. and set it like Bllsht said. That cleaned it right up.

Thanks Bllsht!! :)

"Leroy"

Reply to
Leroy

Even a timing notch on the vibration damper that aligns with the modestly well hidden timing scale. A good bendable mirror and you can see it with everything installed. Not that the timing is adjustable other than with the engine controller.

DougW proclaimed:

Reply to
Lon

You're welcome. Glad you got it handled.

Reply to
bllsht

Well you are right, I went out and looked again and still had no marks so I took a scraper to the area and sure enough, the marks are down there under the mud and crud. Mine have never been cleaned because they aren't used normally.

Mike

Reply to
Mike Romain

So for the record then, you posted the "complete bullshit", not me. Correct?

Reply to
bllsht

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