Hi there

Im new to this so ill try and explain my problem as best as possible.

I have a 1996 Jeep Cherokee Sport with a 4L 6 cylinder engine.

I live in New Zealand so parts for Jeeps are RARE!!! and Expensive!

The first part of my problem is the harmonic balancer. I changed the serpentine belt myself which was fine until when i went to crank the engine again to make sure everything was working the harmonic balancer must have blown its seal. the car seems to run fine although the balancer makes a rattle and until i started getting belt squeak.

So i went looking for a new harmonic balancer, in NZ it is about $500 for a new part if you can find one theres 2 in the country apparently so i thought maybe reconditioning it would be the answer. How would i go about reconditioning the part myself?

Yesterday i was driving around to find a new balancer and nothing seemed to be wrong with car apart from the rattle made by the faulty harmonic balancer, until the engine cut out.

I can start the car fine and it will idle with no problems. although when you put the engine under load (i.e. start driving) the engine will die completely and check engine and GEN light appears on the dash. you are able to restart the engine straight away by revving the engine a lot but then you get backfiring and all sorts of rough running etc. So the cars sitting in my driveway and I've been investigating the fix for it. it seems that crankshaft sensor may be tripping due to the harmonic balancer? is this possible? or are they unrelated?

Any ideas on what might be going on? and my best possible fix?

any help would be greatly appreciated!

James

 

The harmonic balancer is an inner and outer ring with a rubber isolator between them. What normally happens is the rubber gets old and the outer ring starts to work loose and move around.
Can you see it wobble at all while running? I had one chew right through the timing cover on a Chev 350.
I don't know of any way to rebuild them. Is a used (scrap yard) part an option?
Are all the related bolts snug?

The dying out/restart/backfire issue sounds like fuel starvation. Probably worth checking fuel pressure with a gauge for starters.

 

awesome thanks for the insight! so looks like reconditioning the harmonic balancer is a no go?

Yea originally i thought that it might be a filter problem either air or fuel. ill look into the fuel pressure and see what i get.

 

you can recondition them with a new rubber piece. i havent done it myself but i see that the parts stores sell them materials needed to do so. otherwise im sure someone on here could buy one and ship it to you for farely cheap

 

For Giggles, I pulled up the balancer on Rock Auto's website, and calculated shipping to New Zealand. Not knowing where you live, I used postal code 0931.
harmonic balancer is $34.89 and FedEx international economy shipping is $73.04.
Total $107.93
Might be a better option than spending $500 locally.

 

oh really. awesome. ill look into that as well. I'm wondering if the HB would be related to the engine cutting out?

 

thats awesome thank you very much for the help!

haha these forums are great!

 

Some classic motor balancers have to be rebuilt because "new" does not exist.
The process for that involves clamping the rings in a precision jig, pouring black high-temp silicone rubber in liquid form between the rings and letting it set, then balancing the entire assembly by drilling.
I'm not sure I'd trust a rubber insert repair.. bad bonding and/or out of balance and the balancer can launch like a rocket.

 

Nothing is impossible, but I can't imagine how the two would be related unless the engine is shaking so badly it's working electrical connections loose.
The crank sensor is on the other side of the engine, not like the GM V6's that have a reluctor ring attached to the rear of the balancer.

 

this is what my balancer did to my timing cover when it started wondering


its a pretty nice groove thicker than it looks. if you tap the cover where its worn down it almost seems paper thin.

Remember to replace the seal while you have the balancer off. the old seal will start to wear a groove into the snout of the balancer. you could never hope for it to seal on a new one. remember to use an installer tool or some 1/2" by20 rod with nuts and washers to drive the new one on

 

You must play the stereo really loud. LOL.

 

Lol well the balancer was bad before I got the jeep. The squeaking I heard I assumed was the idler so I replaced that an the belt and. That's when I started noticing the balancer. I went out for a trail run. Hour on the highway to get there and it would squeak on and off at highway speed and when I got to the trail and stopped it was leaking oil. That's when I noticed it. Really wasn't any louder than a minor belt chirp. Aluminum isn't super loud when you cut it.

 

Alright. You're off the hook. The PO must have been deaf?