Please help, timing belt issues / internal engine damage

mtgstuber · **Joined:** Tue Sep 13, 2011 4:15 pm **Posts:** 66

The idler pulleys are plastic with a sealed bearing. They don't get oiled or greased, they just sit there and spin, under a fair amount of tension. When I did my timing belt both of the plastic pulleys showed signs of wear, though tolerable. The bigger issue was that the sealed bearing on one of them was clearly worn. You have to face the fact that idler pulleys are a "wear part.". The manufacturer expects them to wear out and be replaced after a certain interval. We're not talking the metal pulleys that the accessory belt goes around, like the ones on the power steering pump, the crankshaft, or the alternator. Those monsters will last pretty much forever. We're talking about a plastic part with a limited life bearing.

It's your money, but I'd replace them when you do the belt. It would really suck to have to redo the timing belt job (or worse) because the idlers failed in another 20k miles.

geordi · **Posted:** Wed Jun 12, 2013 11:59 pm

mtgstuber wrote:

The idler pulleys are plastic with a sealed bearing. They don't get oiled or greased, they just sit there and spin, under a fair amount of tension. When I did my timing belt both of the plastic pulleys showed signs of wear, though tolerable. The bigger issue was that the sealed bearing on one of them was clearly worn. You have to face the fact that idler pulleys are a "wear part.". The manufacturer expects them to wear out and be replaced after a certain interval. We're not talking the metal pulleys that the accessory belt goes around, like the ones on the power steering pump, the crankshaft, or the alternator. Those monsters will last pretty much forever. We're talking about a plastic part with a limited life bearing.

It's your money, but I'd replace them when you do the belt. It would really suck to have to redo the timing belt job (or worse) because the idlers failed in another 20k miles.

See, here's the thing: The description of these pulleys and bearings is correct... Except for claiming that they are any different from the metal pulleys that idle the serpentine belt.

They aren't. Another of our members, PaTracy if I am not mistaken, figured out a while back that the bearings in both sets of idlers were EXACTLY the same, and were also a match to the bearings in many other Mopar engine serpentine belt idlers.

The pulleys are about $17 each at your local dealer, probably cheaper through IDparts.com. Theoretically, you could replace the plastic ones with the metal serp idlers if the outer dimensions were the same. They are that similar. Mtgstuber is also right, it would be a pain to have to go back in and replace those if you didn't do it the first time... But it isn't something that will wear based just on age. The center shaft is a fixed piece around the bolt, so the belt tension doesn't really matter. Bearings of this type are capable of supporting many times the pressure that these are under.

When you open up the timing cover, the question will be - are the pulleys feeling solid, no excess wobble... Smooth rotation, and above all - NO GREASE or filth built up on the front of the bearing? Dust is OK and normal - that comes from the belt itself. As long as it is dry, then the pulley hasn't expelled any grease. Losing the grease is the first step to bearing failure, then they start to howl (LOUD) and then grumble / grind as they really start wearing... Then FINALLY they fall apart and the belt can skip.

I have had many vehicles with this type of belt idler, and 4 different Chryslers with the exact same ones. Just in my family, over 600,000 miles of Chrysler belt idler spinning. ONLY ONE idler ever failed, and that was at over 250k miles on that particular vehicle.

Your mileage may vary... But I wouldn't worry too much about those or the tensioner.

hgrimberg · **Joined:** Mon Dec 19, 2011 11:03 pm **Posts:** 363

mtgstuber wrote:

Hgrimberg,
Yes you need to do the timing belt, but I'd be more worried about everything else. if you haven't been running a GDE tune, or some mod that disables EGR, you've been pumping soot back into your engine. This kills the needle bearings in the rockers. I had no idea. I bought mine new and scrupulously followed the owners manual with regular oil changes, diffential gear oil changes, synthetic 0W-40 etc, and mine failed right where yours is: 81,000 miles.
I don't know if you're mechanically inclined, but if you want to keep yours, buy all the parts, including the rockers, take a week off work, and do the whole lot. Then do something about the EGR. Being clueless about the issue, I ended up with at least one bad valve and had to tear mine all the way down to the head gasket.
My only saving grace was that I have more vehicles than drivers and a very, very, very patient wife.

So, ok, I bought the timing belt on Amazon as Geordi suggested, but what else should I buy and replace? What parts are those? About the GDE tune, I don't think that I will be able to do it in my country. Mechanics are not so clever here. Pitty.

thermorex · **Posted:** Tue Jun 25, 2013 11:13 pm

Since you have somebody do the work and obviously you need to pay labor, I'd spend few more hundreds and also get the pulleys and tensioner, maybe even the water pump, but thats me. But only if you plan on keeping the vehicle for at least least 50 k more. Last thing you want is to replace a pulley 20-30k after you replaced the timing belt... When I did my timing belt replacement, haven't changed the water pump, I was always worried it would fail... which if it does, you see the signs in advance (it leaks). After the rocker replacement I replaced everything, now I have my peace of mind. I guess it all depends on how picky you are, for me peace of mind is very important, lol.

What breaks a pulley is mostly the heat, the grease will came out of the bearing and they will soon start squicking/chirping, imo the quality isn't very good.

hgrimberg · **Joined:** Mon Dec 19, 2011 11:03 pm **Posts:** 363

thermorex wrote:

Since you have somebody do the work and obviously you need to pay labor, I'd spend few more hundreds and also get the pulleys and tensioner, maybe even the water pump, but thats me. But only if you plan on keeping the vehicle for at least least 50 k more. Last thing you want is to replace a pulley 20-30k after you replaced the timing belt... When I did my timing belt replacement, haven't changed the water pump, I was always worried it would fail... which if it does, you see the signs in advance (it leaks). After the rocker replacement I replaced everything, now I have my peace of mind. I guess it all depends on how picky you are, for me peace of mind is very important, lol.

What breaks a pulley is mostly the heat, the grease will came out of the bearing and they will soon start squicking/chirping, imo the quality isn't very good.

So, I will buy the parts online. Are the following parts the ones I have to buy?
2 - 05066926AA
2 - 05142573AA
1 - 05142798AA

I found this picture: http://repairguide.autozone.com/znetrgs ... 200ec9.gif
Which parts should I have to replace along with the timing belt?

Thank you!

thermorex · **Posted:** Thu Jun 27, 2013 12:22 pm

It may be easier for you to just get the set from idparts, lots of us use idparts, its a great resource, very good prices and quality parts.

http://idparts.com/catalog/product_info ... ts_id=2721

I think you'll get the most of your money with this set. But if you just want to do more a budget timing belt, I'd just get the numbers 2, 5 and 7 from your autozone picture, plus the timing belt.

05066926AA - you don't need cam sprockets, you may reuse the existing ones with no issues.

But you need the timing belt if you haven't gotten it already 05142579AA

I'd just get the set for idparts, with the water pump. When you change the waterpump, just replace the pulley part, leave the rest of the pump casing on the jeep, its much easier to do the work and the casing doesn't have any moving parts either, so that won't be an issue if you leave it there. 400 for the whole set is a very good deal.

hgrimberg · **Joined:** Mon Dec 19, 2011 11:03 pm **Posts:** 363

thermorex wrote:

It may be easier for you to just get the set from idparts, lots of us use idparts, its a great resource, very good prices and quality parts.

http://idparts.com/catalog/product_info ... ts_id=2721

I think you'll get the most of your money with this set. But if you just want to do more a budget timing belt, I'd just get the numbers 2, 5 and 7 from your autozone picture, plus the timing belt.

05066926AA - you don't need cam sprockets, you may reuse the existing ones with no issues.

But you need the timing belt if you haven't gotten it already 05142579AA

I'd just get the set for idparts, with the water pump. When you change the waterpump, just replace the pulley part, leave the rest of the pump casing on the jeep, its much easier to do the work and the casing doesn't have any moving parts either, so that won't be an issue if you leave it there. 400 for the whole set is a very good deal.

Wow! $400! I already bought the Gates timing belt. But do I really have to replace the fan belt? That also seems to be included in the kit... Or maybe it is another belt...
I watched this videos on how to replace the belt: http://www.youtube.com/watch?v=mbi3rRSEdA4 and the guy who did it said to me that if you do the witness marks really well when replacing the belt, then you can change only the belt and not the pulleys. Do you really think it is necessary to replace the whole thing?

thermorex · **Posted:** Thu Jun 27, 2013 11:53 pm

The kit comes with the serpentine belt also. Eventually at some point that will also need to be replaced, you should look how your actual looks now.

Regading timing belt tools, you can do without, but its much easier with them. Again, if you think you'll keep the car for a while, you should buy the cam locking tools at least. About 130-ish from ebay, ill look for a link if you are interested.

Regarding what to replace, I can't say till I see the pulley/tensioner condition. They may go for another 50k, or for few thousand. If the bearings are already bad, you should hear them, they tend to get loud when they start to fail. Its your own call what to do to be honest. I'm a lazy person, don't like working every day at the car, so I would replace them all, including the water pump. But if you dont, you'll get plenty notice before they fail, just replace the timing belt, thats a must.

hgrimberg · **Joined:** Mon Dec 19, 2011 11:03 pm **Posts:** 363

thermorex wrote:

The kit comes with the serpentine belt also. Eventually at some point that will also need to be replaced, you should look how your actual looks now.

Regading timing belt tools, you can do without, but its much easier with them. Again, if you think you'll keep the car for a while, you should buy the cam locking tools at least. About 130-ish from ebay, ill look for a link if you are interested.

Regarding what to replace, I can't say till I see the pulley/tensioner condition. They may go for another 50k, or for few thousand. If the bearings are already bad, you should hear them, they tend to get loud when they start to fail. Its your own call what to do to be honest. I'm a lazy person, don't like working every day at the car, so I would replace them all, including the water pump. But if you dont, you'll get plenty notice before they fail, just replace the timing belt, thats a must.

I see, so if I don't replace the timing belt, a catastrophe could happen after the 100,000 miles with my engine, but if I don´t replace the tensioners, pulleys or the water pump, I'll get plenty notice before a real catastrophe can happen, so I'll be able to do it later on. Did I understand well?
Thank you.

geordi · **Posted:** Fri Jun 28, 2013 1:40 am

hgrimberg wrote:

I see, so if I don't replace the timing belt, a catastrophe could happen after the 100,000 miles with my engine, but if I don´t replace the tensioners, pulleys or the water pump, I'll get plenty notice before a real catastrophe can happen, so I'll be able to do it later on. Did I understand well?
Thank you.

Yes, you pretty much have it. The belt is the risky part because it is made of kevlar and covered in rubber. Kevlar doesn't stretch, the tensioner changes position over the life of the belt because the rubber surfaces rub away. When the belt is tired / unhappy, it doesn't announce its intentions. It just snaps. This could happen at idle, it could happen at speed. Either would be a really bad occurrence and the results will not be pretty OR affordable.

The water pump has a very high quality bearing, same for the tensioner - the bearing there is HUGE. The spring in the tensioner will never wear out either. If the dust on the pulleys is just that - dry dust - then the pulleys have not ejected their grease. You won't hear that when it happens, but that is the first stage in failure. It could be a long time after that when they start to really wear and howl... It could be a short time. I don't know - All I know is when they start to howl, you need to start planning for replacement, sooner rather than later. After howling, they will start to grind / grumble noises... That is when the bearings are physically chewing themselves to bits and failure is imminent. The water pump won't do this, it will just start to leak. Small weeping / coolant loss (and coolant alarm on the dash) is what you are looking for, and has the same significance as bearing howl - deal with it soon, but not emergency.

hgrimberg · **Joined:** Mon Dec 19, 2011 11:03 pm **Posts:** 363

Speaking about bearings, i just took out the fan belt and realized that one of the pulleys makes some noise when i make it turn. It looks like the bearings are not ok inside. Could that be dangerous?

papaindigo · **Posted:** Fri Jun 28, 2013 4:20 pm

If it's just one of the serpentine belt idler pulleys drop by NAPA and get 2 36101 pulleys for about $20 or so each (just lose the big washer and they fit fine). Not worth the risk/hassle of losing a belt in the middle of nowhere.

geordi · **Posted:** Fri Jun 28, 2013 11:12 pm

papaindigo wrote:

If it's just one of the serpentine belt idler pulleys drop by NAPA and get 2 36101 pulleys for about $20 or so each (just lose the big washer and they fit fine). Not worth the risk/hassle of losing a belt in the middle of nowhere.

This.

Any unusual noises or it-doesn't-feel-smooth action are indicators of bad operation and failure in progress. Better to replace them now.

Sent from my iPad using Tapatalk HD

hgrimberg · **Joined:** Mon Dec 19, 2011 11:03 pm **Posts:** 363

Well, i discovered that the PO had a crash and had to replace one pulley from the serpentine belt with an excentric generic pulley. So, i replaced it now. The other similar pulley is the original one and since it is 6 years old, it doesnt spin well. In any case it is probably better to have this original old pulley than the excentric one.
I realize that all the bearings after 6 years are broken and therefore, all pulleys have to be replaced in any car. I will suspect that even in japanese cars this happens.

geordi · **Posted:** Sat Jun 29, 2013 2:44 pm

Age alone does not indicate failure of a bearing. I don't know what you mean by 'excentric' bearings, but if the idler pulleys aren't rotating smoothly and feel solid (no wobble) then they have worn from too much mileage and should be replaced. Maybe not all of them need to be replaced, maybe they do.

I have a vehicle currently that has over 250k miles on it, and has only ever needed one idler pulley replaced. The others are all factory. This is a Jeep Grand Cherokee.

My daily driver is a VW Jetta TDI with a similar timing belt system to the CRD, and this vehicle is on track to reach 300k miles before I have owned it for one year. I bought it with 244k on it. While I don't know whether the serpentine idlers are original or not, I know that the timing idlers are NOT original - they get replaced with each timing belt because on the TDI, those idlers and their bearings are very small, especially compared against the larger idlers of the CRD timing belt. The entire pulley and bearing could fit in the space of just the bearing on the CRD's pulley, that is how small they are.

As such, those are spinning at many times the RPM of the belt itself, where the CRD belt idlers are only rotating at around 2x of engine rpm. Wearing out from spinning is the only thing that kills a pulley.

MRausch82 · **Posted:** Thu Jul 11, 2013 9:11 pm

Hatfield: Any updates on this?

Please help, timing belt issues / internal engine damage

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