FAQ: Fragged Tensioner/Idler Pulley Reports & Questions

I was pretty sure I had the alignment correct. I checked and rechecked. 90% of the time it is fine but it occasionally starts deflecting for no apparent reason. Thought I would throw this pic up just to show you guys what I've been running on lol... going to change it tomorrow.

I have looked and looked for a topic to see what has to be done about changing this pulley. The Idler pulley snapped into pieces today and broke a belt. I know what has to be done to change the belt, learning when the water pump went out. can anyone help me out with this

What year is your car and is it Supercharged or not.
Need to add that info in your signature (see FAQ's)
Can't help without that info to start with.

If it's a Series ll with Sc look at this:
https://rivperformance.editboard.com/Supercharged-3800-Tech-c2/Series-II-Engine-Transmission-f4/Write-Up-Replacing-Belts-and-Pulleys-t725.htm

Joby70739 wrote:

I know what has to be done to change the belt, learning when the water pump went out. can anyone help me out with this

Simple answer is replace the pulleys, you can gamble and replace only the bad one along with the belt or you can do what is highly recommended and that is to replace all of them and the belts.
Generally when one pulley goes the rest are soon to follow and leave you stranded. Since the pulleys average about $20.00-$25.00 each, at the auto parts store, it is well worth it.
Look at the write up above, it's for a S2 SC engine and may or may not pertain to yours but there is good info in that write up for any of these engines. Some info is pertinent and some is NOT (if you have S1 engine).

It is a 98 S2 SC.

Idler on the SC belt or idler on the main drive belt???? Makes a difference....That big fat engine mount and bracket need to be moved out of the way depending on which belt it is...

Also have to say which pulley; some of them have axle bolts 'reverse threaded.'

BTW RIck is right - once one goes the rest follow pretty soon. Not because of superstition, rather because of engineering. They only last so long, give or take a few thousand revolutions. So for a given composition of metal in teh pulley bearings and given compostion of pulley material, they are designed to last a long time but they only last so long, and when one has an 'end of life' event the others will follow soon.

Maybe the thing to do is post a picture (cell phone cam, need not be perfect) showing the one that failed and where it is on the engine. After replacing that one, then in a week or so make a project of replacing all the rest. i think the folks on here can pretty much tell you what has to be done if it was clear which pulley you're talking about.

Albertj

It's the SC belt Idler pulley. When I changed the water pump I also changed the tensioner pulley and the 3.0" grooved idler pulley. That was a year ago. And yes the motor mount is in the way but that has to come off anyway to put the new belts on. By what I am looking at it is the 3.5" smooth idler pulley. Which is right by the motor mount. I think I have it figured out I'll just need a little help from my husband.

mmmmk. Which pulley are we talkin bout in the SC drive? If you haven't done so, like everyone has suggested I would replace both idlers and the tensioner pulley while you have it apart....

Joby70739 wrote:

It's the SC belt Idler pulley. When I changed the water pump I also changed the tensioner pulley and the 3.0" grooved idler pulley. That was a year ago. And yes the motor mount is in the way but that has to come off anyway to put the new belts on. By what I am looking at it is the 3.5" smooth idler pulley. Which is right by the motor mount. I think I have it figured out I'll just need a little help from my husband.

Actually on the later Rivs you *don't* have to take the idler pulley off to replace the belts. Here is an FYI for later, if you have to change belt for some reason but don't have to change idlers - like maybe the belt glazes and squeaks or some such. When you are looking at the front (passenger side) of the engine, the lower right bolt in the front motor mount goes thru a ferrule. Probably the first thing to do is clean off that area of the engine so you don't get oil on the belt. Then you can support the car and engine (DO NOT support engine by the oil pan, the pan gasket will crush and start to leak you'll have to replace it too) and remove the front pass side wheel. Then you can remove the plastic inner fender - a handful of plastic clips they just pull out - and wha-la the whole thing's in front of you and actually pretty easy to reach. The engine should be supported only because it keeps the bolt and holes lined up easy - anyway with that stuff out of the way just unscrew the front lower right bolt out of the mount, if everything is lined up the ferrule will drop free. Slip off remnant of old belt, put new belts on, reinstall ferrule and bolt, put the liner back in and the wheel back on... you're good to go.

To the best of my knowledge you can't replace the lower idler this way, the bolt is too long (oh, if only you could!!). But you can swap a belt relatively quick, don't *have to* undo the mount.

Albertj

albertj wrote:

To the best of my knowledge you can't replace the lower idler this way, the bolt is too long (oh, if only you could!!). But you can swap a belt relatively quick, don't *have to* undo the mount.

I just changed the other idler pulley it's just the smooth one I have to change. Behind the motor mount, lucky me. Going to start on it tomorrow.

Hey there, this is Joby's son... Well, we have the pulley and belt replaced, but now the car isn't starting. My step father believes the timing jumped when I cranked the car after pulley had initially broken (I was the one driving it at the time.) In retrospect, that was not the best of ideas... In any case, is there a way to check for that, or would something else be the cause for the engine not starting?

Nez wrote:

Hey there, this is Joby's son... Well, we have the pulley and belt replaced, but now the car isn't starting. My step father believes the timing jumped when I cranked the car after pulley had initially broken (I was the one driving it at the time.) In retrospect, that was not the best of ideas... In any case, is there a way to check for that, or would something else be the cause for the engine not starting?

What happen when he was driving was- he was at the drive thru at McDonalds and he herd a pop which was either the belt or the pully, then the car died. He got the car to crank again and drove it about maybe 100 yrds away and it died again. wouldnt crack after that and he saw the belt was broke. So towed the car to my house and changed the pulley that broke and replaced the belt that snapped. Would anything he did make the car jump timing or why would it not run now. Turns over and thats about it. Any ideas Im open for trying just about anything.

Timing would only jump if your timing chain was stretched and it skipped a tooth or something. If the BELT broke, it has nothing to do with timing. You should be able to run the car with no belt (not for long, it's your water pump). Take the belt off and see how the harmonic balancer feels. They have gone bad in the past, and the Harmonic balancer feeds a signal to the crank position sensor, which would ruin your timing and make it run poorly.

When it is running, is there a check engine light? If so, what's the code?

It wont run period. Water pump is fairly new and isnt locked up I dont believe it is the water pump. Throws no codes whe hooked up to the reader.

Can you check for the basics - is there spark? Fuel Pressure?

Yes there is fuel pressure and spark

What would a pulley and belt breaking have to do with fuel and spark? nothing around the coil was touched. Its should have just cranked right up. I wasnt sure if the fact he cranked it with no belt at all and drove it then tried to crank it more for I dont know how long threw the timing off. I am fairly sure it is not the chain because I would here it clanking around while turning over.

Joby70739 wrote:

What would a pulley and belt breaking have to do with fuel and spark? nothing around the coil was touched. Its should have just cranked right up. I wasnt sure if the fact he cranked it with no belt at all and drove it then tried to crank it more for I dont know how long threw the timing off. I am fairly sure it is not the chain because I would here it clanking around while turning over.

Pulley and belt should have nothing to do with fuel or spark. You have a car that won't run, and we don't know your background, so we need to start with the basics. Fuel and Spark. Timing is controlled by the crank and cam sensors. Quite possibly the belt coming off damaged the wiring from the crank or cam sensor. They are tucked down under the coil brackets, and at this point you should probably be continuity testing those wires. I would expect there to be no spark if one of the crank or cam sensors wasn't reporting. How did you confirm spark? How did you confirm fuel? Can you tell if the injectors are firing?

I also doubt it's the chain. The loud bang mentioned earlier was probably the belt coming off the tensioner, releasing it's tension.

I hope you took the time to change all the pulleys while you were in there, or at least all the pulleys associated to the SC belt (#8 and #9). They all have the same lifespan. You can refer to this thread for more info.

The other one was changed with the water pump when it went out a year ago. The Idler pulley was the oldest one.

Joby70739 wrote:

It wont run period. Water pump is fairly new and isnt locked up I dont believe it is the water pump. Throws no codes whe hooked up to the reader.

No codes = very likely crank sensor

reason - during start up sequence if there is no signal from crank sensor, car will crank but will not start and will not set a code. The Vetronix "Tech II" scanner will read the crank sensor signal - a code reader will not.

You would benefit from the factory service manuals if you do not have them already. Usually they are available reasonably priced via eBay.

Albertj

https://rivperformance.editboard.com/care-maintenance-f8/dont-know-what-to-do-now-timing-t6908.htm

Thinking it is a frayed ground wire for my ignition module connector. posted a topic

Fixed it, Thanks everyone. It wasnt a fun job pulley the harmonic balancer to get to the sensor but I got it done.