violent Shake @ 45mph

[NewToJeeps]

its got brand new plugs wires and a new cap and button. compleat new tune up. the cables for the battery and starting system have been replaced. i did that when i had the NNS penny jammed in the shifter problem...long story lol. basically i can't figure out why this thing won't time up and run right. i really dditn believe the timing was the cause of the shake but i went and started messing around with it anyways. Bad idea i guess lol.

 

This thing is turning into one big headache. I got it for cheap so i can't complain about the problems i just don't need to be stuck with something this unreliable nor do i need another parts hungry vehicle. I'm having a bad day and I'm a little mad at it at the moment so scrapping it came out of my mouth lol. if i did scrap it would be on here where someone got use out of it. but I'm not ready for that yet. i am however thinking that i may just keep the body and make a chevy powered jeep. it would be fun with a 327 in it. i am waiting to see if i can get this timing problem and a few other things fixed first though. If its simple i'll leave it alone. if its going to end up having a major problem i will put me a chevy v-8 in it.

[Eagle]

The timing is not adjustable. Just exactly how did this genius determine that the timing was wrong? One tooth on the distributor drive gear is a bit more than "a hair."

[NewToJeeps]

actually when i got to looking at it, it seemed to be 180* out. I don't think it was exactly that much out but it was out. Apparently just enough for it to run but not run well. Its had a rough idle since i got it. thats why i tuned it up and figured out the vacuum line problem. Anyways the timing was off and i did it the way i have always done chevys and pulled it up on TDC and reset the distributor. This is the first time i have messed with anything that wasn't adjustable so i probably should have left it alone. Now i have a problem i can't seem to fix. Maybe its a tooth off now or something but its been the kind of day that i needed to walk away from it :mad: now I'm back here begging help again lol.

[Eagle]

You're certain you were at TDC on the compression stroke, and not the exhaust stroke?

 

There was a TSB out on a timing correction for the Renix 4.0L engines. Apparently some of them must have had either a bad drive gear or the gear on some aftermarket camshafts was out of spec, causing the timing to be slightly off. The fix was to grind the locating ears off the distributor so it could be manually adjusted. Then it was set so that the rotor was NOT pointed exactly at the #1 contact in the cap, but slightly after it.

 

If anyone has access to Alldata, we're looking for TSB #18-53-88.

 

I remember that setting it involved taking an old distributor cap and cutting away the side around the #1 terminal. Then you use a feeler gauge to check the clearance between the tip of the rotor and the #1 contact on the cap. The clearance is supposed to be 0.020 when the #1 pistol is EXACTLY set at TDC. The rotor is supposed to be on the "departing" side of the #1 contact in the cap. In other words, there should be a gap of 0.020" between the cap contact and the trailing tip of the rotor contact.

 

Be sure the #1 piston is at exactly TDC when you check this, and be sure #1 is on the compression stroke, not the exhaust stroke. Believe it or not, the 4.0L engines still have a set of timing marks on the front cover, and the harmonic balancer still has an index line. Use that to set #1 at exactly TDC, don't rely on eye-balling it.

[chicofuentes0224]

Yes sir 18-53-88 sir

 

http://www.alldatadiy.com/alldata/AFI~V10369567~C27515~R0~OD~N/0/34870067/56416621/56416628/56418252/34853741/34850750/42063452/120832951

[Eagle]

Gracias, Chico

[NewToJeeps]

Thanks for that info Eagle. I will go cutting on my old cap tomorrow if i get time and check it.

I was thinking about grinding the little ears that hold the distributor in place off of it before i read this but i was going to check the price of a new distributor first just in case. I know how my luck normally is lol.

 

Thanks for the efforts on the alldata thing but i don't have a membership there so i can't see it. if someone could be so kind and copy and paste the importaint parts or email it to me it would be very helpful

[Eagle]

The Alldata article should just confirm what I already posted. The actual factory TSB had a line art picture of the cap with the "window" cut in the side, but the procedure is the same. The key is to use the timing marks on the front cover to ensure that the crank is at exactly TDC -- and, of course, to be certain you're on the compression stroke and not the exhaust stroke.

[chicofuentes0224]

Ignition System - Engine Bucking/Surging

 

 

 

Models

 

1987-88 Comanche Wagoneer And Cherokee With 4.0L Engine

 

Subject

 

Engine Ignition Cross Fire

 

Index

 

DRIVEABILITY

 

Date

 

July 25, 1988

 

No.

 

18-53-88

 

P-2927 (C18-55)

 

SYMPTOM/CONDITION

 

Some 1987-88 Cherokee, Wagoneer and Comanche vehicles with the 4.0L engine may exhibit an engine ignition cross fire during vehicle operation. The ignition cross fire will normally occur as a harsh bucking or surging condition.

 

NOTE: THIS BULLETIN SUPERSEDES DISTRIBUTOR INSTALLATION PROCEDURES IN I.S. NOTES 31E, 40E, 42E (M.R. 244) AND 21E, 34E, 36E (M.R. 277).

 

 

DIAGNOSIS

 

Road test the vehicle with the MS 1700 Diagnostic Tester in the "State Display" test mode. Observe the engine vacuum and record the vacuum reading when the cross fire condition occurs. An engine cross fire complaint will be repeatable at the vacuum range which was previously recorded regardless of engine vehicle speed.

 

If a cross fire condition is diagnosed, proceed with the following repair procedure.

 

PARTS REQUIRED

 

Distributor Cap (1) PN 33004024

 

REPAIR PROCEDURE

 

1. Turn the ignition switch to the OFF position. Disconnect the battery negative terminal.

 

2. Remove the coil wire and spark plug wires from the distributor cap.

FIGURE 1

 

 

3. Remove the distributor cap (A) and cut a "window" © into the side of the distributor cap at the #1 spark plug wire post (D). The "window" should be large enough to allow easy visual inspection of the position of the distributor rotor (E) at the #1 spark plug wire post. Reinstall the distributor cap. Figure 1

FIGURE 2

 

 

4. Install a wrench or socket onto the vibration damper retaining bolt (F). Rotate the engine in a clockwise direction until the #1 cylinder is at top dead center. Align the timing mark (G) on the vibration damper (H) with the "0" degree mark on the front cover timing scale. The tip of the distributor rotor should be near the #1 spark plug wire post. Figure 2

FIGURE 3

 

 

 

 

5. Disconnect the distributor electrical connection. Remove the distributor holddown clamp, holddown bolt and distributor. Remove the distributor cap and rotor.

 

6. Place the distributor housing upside down in a soft jaw vise. Scribe a line (I) 1/2 inch from the end of the distributor locating tab (J). Cut the distributor locating tab at the scribed line with a saw.

FIGURE 4

 

 

 

 

7. Remove any burrs and metal filings from the distributor. Reinstall rotor.

 

8. If necessary, using a flat blade screwdriver, turn the oil pump gear drive shaft (B) until the slot is slightly past the 11 o'clock position. The oil pump gear drive shaft is accessible through the distributor mounting bore (N) in the engine block. Figure 4

FIGURE 5

 

 

9. Visually align the modified locating tab area (K) of the distributor housing with the holddown clamp bolt hole (L). Figure 5

FIGURE 6

 

 

10. Turn the rotor to the 4 o'clock position. Figure 6

11. Lower the distributor into the engine block until it seats. The rotor should now be very close to the 5 o'clock position. Figure 6

FIGURE 7

 

 

12. Reinstall the distributor cap with the cutout "window". Rotate the distributor housing until the trailing edge of the distributor rotor tip(E) is just departing from the #1 spark plug wire post terminal (D). Figure 7

 

13. Reinstall the distributor holddown clamp and bolt. Tighten the holddown bolt to 9.5-14 ft.lbs. Reinspect the position of the rotor to the #1 spark plug wire post to insure that it has not moved.

 

 

14. Install the new, distributor cap, reconnect the distributor electrical connections and the battery negative terminal.

POLICY: Reimbursable under the provisions of the warranty.

 

 

SRT/TIC INFORMATION:

 

OPERATION

OPERATION DESCRIPTION NUMBER TIME TIC FAILURE CODE

 

CO. DISTRIBUTOR ADJUST - 0106 0.6 1717

4.0L CROSS FIRE 08-15-24-90 0.6 RO-DRIVEABILITY

 

Copyright © 2008 ALLDATA LLC

[chicofuentes0224]

Here's the firgures in order if ya need em.

 

 

 

 

 

[NewToJeeps]

thanks again Eagle and chicofuentes0224. i'm about to go get started on it and see what i can get done. Maybe it will go smooth.

[Eagle]

Keep in mind that you aren't certain this was the problem. Thanks to the guy at the tranny shop talking you into yanking the distributor, you now don't know if the distributor is installed correctly or not. Before you start grinding on the locator tab, I suggest using the information in this tech bulletin to see if you can get the distributor reinstalled correctly and see if it aligns correctly with the notch. If so, there's no need to remove the locator tab.

 

"If it ain't broke, don't fix it."

[chicofuentes0224]

Listen, if this doesn't work, just for craps and giggles, remove the rear shocks and test em. Mine wouldn't decompress and caused a shaking at highway speeds that wasnt DW but wasn't mild either. Changed the shocks and no more shaking.

[NewToJeeps]

well i got the timing problem fixed and along with it fixed a few other problems i hadn't got to yet. I didnt have to go grinding or cutting on anything but the old cap. i cut me a window in it just to make sure i was in the right place and i wasn't. AFTER me messing around with it, it was a tooth out for sure so i put it back. now its running fine timing wise.

 

The shake has all but gone away too. the timing issue was the main problem i guess. it still has a little vibration to it but its not the violent shake i had to start with. I am almost certain this time the vibration is from the tires. I put them on and balanced them myself on an old bubble/level machine so I'm almost sure they are out of balance a little. A simple trip the the tire store should fix that though so I'm back on the road again..

 

Tomorrow the jeeps gonna drag an old hay bailer out of a bunch of briers and weeds and take it to the scrap yard so i may be back later with a new problem lol Naw she'll hold it... i already put half of an old dozer behind it :D

[Eagle]

"I love it when a plan comes together."

 

- Hannibal, The A-Team