Main IndexAuto Repair Home Search Posts SEARCH
Who's Online WHO'S
Log in LOG

Search Auto Parts

'02 liberty secondary timing tensioner replacement - now won't start

  Email This Post

New User

Jun 9, 2016, 8:34 AM

Post #1 of 3 (748 views)
'02 liberty secondary timing tensioner replacement - now won't start Sign In

I would greatly appreciate some help! I have an '02 jeep liberty 3.7L with about 150k miles (replaced the engine with remanufactured engine about 30k ago). It started rattling, so took off valve covers to find out the passenger side timing chain (DOHC) was bouncing and hitting the upper nylon guide causing the rattle noise.
I tore down the front and took off the timing cover to find the tensioner had basically fallen apart - the center screw that locks in the 'ratchet pin' of the tensioner was gone, and the bouncing had damaged the tensioner arm a bit. The end of nylon was broken off of the tensioner arm and a small piece was chipped off of the arm where the 'ratchet pin' would contact the arm. I replaced both parts with minimal problems.
A couple things I noticed during the work
1) alternator wire sparked/shorted at one point after I disconnected it and accidentally dropped it. I taped it afterwards to protect it from happening again, but I wanted to mention this.
2) after new parts were installed - turning over revealed that the chain still had a tiny amount of slack, allowing every rotation to barely tap that top nylon guide up closest to the cam shaft again. It wasn't nearly as loud, but it was obviously still there. I pushed up the ratchet on the new tensioner to lock up another notch which removed the slack. It turned over smoothly/quietly after this, but there was more resting tension on the repaired chain vs the untouched driver's side chain.
It's now back together and wont start. It has spark, it has gas on the rail. I probably flooded it a bit the night before last, but it still didn't start again last night while troubleshooting. I've checked most pertinent fuses I can think of. I'm pretty sure I have all the electrical plugs/sensors re-attached. I rented a diagnostic computer and it didn't help me much - no codes would come up after I cleared the initial codes (knowing the engine light had been on prior to the repair.)
1) was this tension adjustment for the timing chain okay? why the extra slack? Maybe the chain stretched a little while parts were damaged?
2) any suggestions as to why it won't start?
3) I don't think I moved any timing gears, the engine was not turned over while tensioner parts were removed. Could the timing have gotten off? It started up easily prior to the repair with the damaged parts.
4) could I have an electrical / computer problem from the spark causing this?
Any suggestions to try or to troubleshoot are much welcome!!

kev2 profile image

Jun 9, 2016, 11:15 AM

Post #2 of 3 (737 views)
Re: '02 liberty secondary timing tensioner replacement - now won't start Sign In

1) it likely stretched I would not have torn that much engine apart without replacing the timing chains, tensioners. My colleagues will add their 2 ¬Ęs.

2) All no starts are the same - is there spark at several plugs, what is fuel pressure are inj pulsing and of course codes.

3) If the timing is off I suspect there will be codes, sensor and 'sync'

4) BASIC trouble shooting - spark at several plugs, fuel pressure GAUGED, Injector pulses, and the codes - might want to check ALL fuses in vehicle and under hood...

Ultimate Carjunky / Moderator
Discretesignals profile image

Jun 9, 2016, 5:58 PM

Post #3 of 3 (718 views)
Re: '02 liberty secondary timing tensioner replacement - now won't start Sign In

Did you verify that the colored marks were in the right spots? Did you mark anything? Those cams will turn due to spring pressure when you remove the chain. The right bank has the cam sensor, so if that cam is off, the engine probably won't run. Looks like you'll be pulling the cover off again. Hopefully you don't have bent valves.

If I saw that crap, I would of installed a whole new timing chain kit including all the sprockets, guides and tensioners. That engine is interference and isn't worth trying to cobble up timing components to make it work.

Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.

(This post was edited by Discretesignals on Jun 9, 2016, 6:06 PM)

  Email This Post

Feed Button

Search for (options) Privacy Sitemap