How to tell if Timing Belt has been replaced?

DFWBIOFUELS2 · **Posted:** Sun Jun 15, 2014 4:50 am

My CRD has 134k miles on it. But there's no record of the timing belt job in the factory service records.

It looks like a mechanic used an air chisel to remove the fan clutch nut. I've seen this technique done before.

What physical evidence would you search for on the vehicle to determine if the TB has been changed?

papaindigo · **Posted:** Sun Jun 15, 2014 6:55 am

There is no physical evidence that I know of which I would trust. In theory if you undo the top few bolts that hold the TB cover (black sheet metal) in place you can see the TB. Then in theory you might could rotate the TB, bump the starter, to a point where you can see it manufacture's information. Presumably if it's not a Mopar belt (say it's Gates) then it was replaced. If it's Mopar who knows and if it's a Gates or some such who knows when the job was done.

For $399 and a days work doing it yourself with the proper tools my recommendation is just do it.

mikey1273 · **Posted:** Sun Jun 15, 2014 8:51 am

My orig belt was goodyear. I can attest to it not being in super condition after 94,000 miles what was suggested is about the only way to know other than changing it out

tedder · **Joined:** Thu Sep 15, 2011 7:19 pm **Posts:** 137

I had a dealer replace the belt in part of the purchase deal. I just recently, out of concern that the rockers could fail 110k miles as my wife's bert did, replaced the rockers in mine. The TB looked worse than the one the dealer changed out at 87k. The idlers looked bad too. So I replaced them just to be sure. The morale to the story is if you are unsure replace it. The alternative is when the belt brakes is to replace the rockers and belt which is a $1000 in parts and depending on your experience a lot of time. Or about $5000 at the dealer if you can't do it. Belt change at the dealer is $1600 including the WP if you have a stealer you trust. So there are your options live well my friend. :SOMBRERO:

DFWBIOFUELS2 · **Posted:** Sun Jun 15, 2014 12:48 pm

There's a good multi part series on YouTube on replacing the Timing Belt as well as write ups here.

So I'll be biting the bullet and getting this done in my garage this week if time allows.

Thanks for the support guys.

DFWBIOFUELS2 · **Posted:** Sun Jun 15, 2014 12:51 pm

While I'm in there, should I replace the serpentine belt tensioner ($169.50) and thermostat ($129.95)?

Prices on idparts.com.

thermorex · **Posted:** Sun Jun 15, 2014 1:26 pm

If you have issues with warming up (hard to tell in the summer with a partially opened thermostat) you should replace the thermostat. What I'd advise would be to purchase the parts, both thermostat and serpentine tensioner, and keep them on the shelve in case you need replacement. You can replace both later on, if you need, after you did the timing belt job, since they don't require removing anything that is timing belt dependent. Maybe for thermostat you'll loose some coolant...

What I'd recommend: when you replace the first half of the water pump (from the kit on id parts, do a coolant flush and refill with new zerex g05, since it is doubtful it had been done, and per manufacturer recommendation this should be flushed at 100k.

To see if the thermostat is ok, in the summer, on over 60 temp, the gauge should stay perfectly vertical and a tic to the left. When you go uphill, if you don't tow and hammer it like you stole it, it should not climb at all. Obviously this is dependent on how the fan clutch is working, it is recommended to go with either an e-fan, either a hayden severe duty clutch (Sam's NOOB should have the part number and there is a tech forum post about e-fan conversion with an ff dynamics) . A partially opened thermostat would seem to be working fine in the summer, but engine will tend to overheat while going on a sustained uphill. If you do not know how this engines work, you won't know you have a problem till weather cools down... Crd engine should not overheat unless you tow thousand pounds uphill, even that should not push the gauge more than 3/4.

The serpentine belt tensioner can be replaced anytime, you can see if the belt is "jumpy" but also that can be because of the alternator pulley if it goes bad.

It may not be a bad idea to just replace both thermostat and serpentine tensioner, especially if you're not used to how the engine normally works.

papaindigo · **Posted:** Sun Jun 15, 2014 3:02 pm

For what it's worth.

The OEM tstat seems to last about 30-50K mile and generally fails open or opening early. As a result the engine coolant won't reach full operating temp (temp gauge typically sits a bit above the 1/4 mark) and you will have about a 10% mpg hit. That said I know from personal experience that with ambient temps in the 85+F range, especially with AC on, even with a bad tstat coolant will reach operating temp (e.g. gauge vertical or maybe a needle width left of vertical). You can drive this way for quite a while with no harm at least I did for several thousand miles including N. FL summer when coolant did reach operating temp. Normally it takes about 1-2 miles of in town driving for me to reach normal operating temps given current ambient temps here which should be roughly similar to you so if it takes noticeable longer for you then your tstat probably needs replacing and of course if coolant won't reach operating temp during the winter months it needs replacing. Replacing separate from a TB job is no big deal; you only lose a small amount of coolant (none if you drain the coolant into a bucket for reuse) so if your tstat is good I'd wait.

The serpentine belt tensioner rarely fails (it's a spring and a pulley bearing) EXCEPT when stressed too long by a failing alternator clutch pulley which typically causes the tensioner to bounce all over the place at idle. If it's not bouncing the alternator pulley is ok. I would not routinely replace the tensioner although if you want you can replace the pulley (NAPA 36101 - same as the serpentine idler pulleys).

I would replace the TB idlers and tensioner even if they are not leaking grease (mine were at 50K) just because of how hard they are to get too. If the serp belt idlers look and feel ok there is no big need to replace them as they are easy ot get to (Note - on those idlers you can drill out the rivets; remove the bearing; replace bearing (it's a standard size but I don't have the size - there are post on how to); replace rivets with short bolt/nut combos.

DFWBIOFUELS2 · **Posted:** Sun Jun 15, 2014 11:28 pm

I got some quality time under the hood today. My goal was to inspect the #1 Glow Plug and determine if the original ceramic 7v GPs had been replaced with 5v GPs. I was able to pull #1 with very little trouble. It has a white band and printing on the side. Its marked Bosch 7v. So there's the answer to that question.

QUESTION #1 Now should I replace them with the 5v? My relay is the part number corresponding to the 5v swap.

The next goal was to pull the timing belt cover at the top and get a look at the TB. To my surprise, the TB cover bolts had fresh looking blue loctite on them.

I got the top part of the cover back far enough to inspect the belt. I marked it and bumped the starter so I could inspect every inch at least from the side. Belt appears to be fairly new. It's a Goodyear.

QUESTION #2Combined with new blue loctite, what would you guys conclude?

Third task of the day was to pull the MAP sensor. Very easy task and BOY was it dirty. Completely clogged with soot. I bought some MAF cleaner and got my compressor tank full of air. I cleaned every visible spec of carbon off that guy and blew it out multiple times with air. Reinstalled and started up. She purrs like a kitten.

Final task was to pump up the fuel filter head and bleed off any air. That took about 4 cycles.

Buttoned it all up. Went for a test drive. Can't wait to get behind the wheel tomorrow. This is a WHOLE lot more pleasant to drive than my F250 CCSB 6-spd 7.3L.

I read up on the thermostat and actually knew about how this behaves when stuck open. My CRD Tstat is working fine. Coolant temp comes right up very quickly to vertical and stays there.

DFWBIOFUELS2 · **Posted:** Mon Jun 16, 2014 1:06 am

Provent has been ordered.

geordi · **Posted:** Mon Jun 16, 2014 1:16 am

The belt looks to me like an old one. The replacements I have seen are all Gates brand, Goodyear seems to only be the dealer replacements, and that would have been logged in the service records even if it wasn't a warranty job. They are supposed to log everything they do to a vehicle.

I didn't see any obvious cracking, but that doesn't mean it isn't there. For the peace of mind, I'd still be thinking about a belt job.

DFWBIOFUELS2 · **Posted:** Mon Jun 16, 2014 1:48 am

geordi wrote:

The belt looks to me like an old one. The replacements I have seen are all Gates brand, Goodyear seems to only be the dealer replacements, and that would have been logged in the service records even if it wasn't a warranty job. They are supposed to log everything they do to a vehicle.

I didn't see any obvious cracking, but that doesn't mean it isn't there. For the peace of mind, I'd still be thinking about a belt job.

Plus there's air chisel marks on the fan clutch nut. I've seen the techs at Firestone and Goodyear using that method. I'll order the timing belt kit and get it done to be completely thorough.

WolverineFW · **Posted:** Mon Jun 16, 2014 2:59 am

mikey1273 wrote:

My orig belt was goodyear.

Ditto

WWDiesel · **Posted:** Mon Jun 16, 2014 6:08 am

DFWBIOFUELS2 wrote:

Third task of the day was to pull the MAP sensor. Very easy task and BOY was it dirty. Completely clogged with soot. I bought some MAF cleaner and got my compressor tank full of air. I cleaned every visible spec of carbon off that guy and blew it out multiple times with air. Reinstalled and started up. She purrs like a kitten.

You may want to order a new MAP sensor and save the old one as a spare? We discovered the following part numbers are all interchangeable with the GM one being the least expensive. It is best to always have a spare!
Bosch 0281002437 or 0281002845 Intake Manifold Pressure Sensor
GM Part No. 55206797
http://www.gmpartsgiant.com/ has them for $18+ some change.
Unplug your MAF sensor located on the intake boot until you can get a tune, this will disable the EGR valve and stop the constant flow of poop into the intake manifold which is what is fouling the MAP and everything else in the top of the motor. Running with the MAF unplugged will not cause any problems other than tripping a CEL.
Get a tune ASAP, your engine will love you for it!!!!! :BANANA:

geordi · **Posted:** Mon Jun 16, 2014 10:20 pm

Dealer chimps have been reported to also use the air chisel method to get the fan nut off too. Napa sells the proper 36mm flat wrench for about $27.

About the MAP sensor: Nothing wrong at all with the GMpartsGiant link, but for $3-$7 more... I'd give my money to IDparts and support the vendor that has been relentless on sourcing the best parts for these orphan vehicles. As an added bonus, if you are already buying the timing belt kit (and the Graf water pump is BETTER than the OEM!) then there shouldn't be any added shipping for such a small add-on as that sensor - they will just drop it in the box.

No promises on savings if you go on a shopping spree for other toys. They have quite a lot of cool stuff on that site.

thermorex · **Posted:** Mon Jun 16, 2014 10:29 pm

Agree with Geordi, id parts are some nice fellas and I buy from them even if the price is lightly greater versus other vendors. But most of the time they beat every price.

laplaya · **Posted:** Mon Jun 16, 2014 11:56 pm

In addition I would hazard a guess that you are a fairly handy fella. Make your own tools and use some of suggestions here for the TB job. Easy as hell and far cheaper. As a first timer I used sams guide from u tube for the most part, and as a noob to this engine it was a lifesaver and great. However when you have done it once and are more comfortable with your libby there are other ways to do this work. Although you have probably figured it out by now you have found the "holy grail" of CRD info and help by joining this group.
Good luck with your projects.
It seems to me with these critters an ounce of prevention is worth MANY pounds of cure and you appear to be erring on the side of caution, that's a good thing.
AL

DFWBIOFUELS2 · **Posted:** Mon Jun 16, 2014 11:59 pm

What tools do I need to make?

I'm not a pro mechanic but I have done this type of task before there was YouTube and forum communities.

thermorex · **Posted:** Tue Jun 17, 2014 7:48 am

For timing belt there is a kit on eBay (sealey) that has the locking pins and tensioner wrench, and for the sprockets you can either buy the "v" tool from idparts.com (I think they have it as a vw cam sprocket tool), either make your own (the v tool is just to help keeping the sprocket in place when you torque/untorque the bolts. This v tool is a cheaper alternative to the Miller cam sprocket tool the crd needs for locking the cams. I think it is more convenient to get the sealey kit from eBay rather than making your own, but that depends on preference. Just search "sealey jeep crd" on ebay, I think the seller is in UK.

This link shows you some details, I think is referenced in the noob guide, it also shows the vw v tool:

http://www.beesvillebeefarm.com/jeep.html

DFWBIOFUELS2 · **Posted:** Tue Jun 17, 2014 8:45 am

Does anyone in the community have specialty loaner tools available?

I found this Chinese kit on ebay. Looks to have the tensioner wrench included for $60.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=221440906365

How to tell if Timing Belt has been replaced?

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