I have a '94 Sidekick with 81K miles. I bought it w/ 19K miles and have been doing regular maintenace since.

The timing belt was replaced before 60K miles, about 3 or 4 years ago. It's been running great but last weekend was nice, so the windows/top were down and I noticed a noise from the engine. (It was a rattle, almost as if the manifold cover was loose.) By today, the noise is louder and troubling. The dealer and a shop (2 estimates) thinks it could be the idler puller for the timing belt.

The thing is, the idler noise seems to be intermittent, but it sounds as if noise is coming from the entire upper end, with key points around #3 cylinder and from the distributor. I don't think it's skipped a cog in the belt, since it still starts and runs well. (It may be idling a couple hundred RPM high, but that's probably another problem.)

Thoughts?

Valve train noise
check for oil on the top end, more than
one cam has siezed from lack of oil.

 :-/ OK... but how do I test this???

From the symptoms, this sounds possible.

Dont worry. Ive owned 3 suzukis one with127k one with 60k and my latest one "94 tracker" with 59k. And mine all sounded like sewing machine. I'd go ahead and get it checked but if it's an 8valve ,most all of them have V,T noise.

Don't know if this is true or not but I've read that a Zook should sound like a sewing machine. If not, the valves are set too tight and you risk burning a valve. It's a fine line between tight enough and too tight. Many of them also suffer from piston slap, as mine does, but it doesn't seem to affect longevity.

TN_T

Run a compression test.  It does NOT sound like a timing belt tensioner - I mean geez, it's a rubber belt, and the tensioner is just a bearing with a wheel around it.

:-/ OK... but how do I test this???

From the symptoms, this sounds possible.

Start the engine with the valve cover off and look
for oozing oil coming out of the rockers/shafts area.

Does anyone have pix of the 5 spoke cam gear in their manual? If so, could you e-mail them to me at mperry|removethispart|@efn.org??? (thnx, if possible.)

Well, I have it apart... and a serious problem in how to put it back together. Does anyone know how to make sure the timing belt (cam) hasn't slipped forward? The car was running fine (except the noise) when I shut it off. Naturally, I set the crank to #1 cylinder TDC and the lower gear aligns properly with its mark.

I have a manual, but it doesn't show pix of my particular cam gear and the alignment mark they show doesn't exist. This is the gear with 5 spokes.

There is a white mark on the gear and one the engine, which would indicate that's where it should be aligned... but the mark is 4 teeth (36 degrees) retarded of the alignment when I took it apart. I can't remember whether that white mark was used the last time I took it apart. (It's been several years and I do recall some confusion then.)

To make matters more confusing, there is a bump on one of the "spokes" and there's a notch in the face of the cam gear. When I set the gear to its position it was in when I took the engine apart, and run a straight edge through the center of the gear, notch, and bump, they align with the notch in the engine. (Thus, either mark *could* be correct.) Thus, this notch would align if I took the crank to TDC #3 cylinder. (I do recall this from the last time I took it apart.)

The distributor doesn't seem to be a whole lot of help. Its odd angle and the width of the rotor could make either a possible match... or any tooth in between. <g>

I'm thinking of putting it together and cranking it over with a timing light (valve adjusters backed off) to see where the mark falls. I've never adjusted the distributor, so I'm hoping timing was about right.

Thoughts?

What I found when I tore it apart...

Yep, the engine sounds like a sewing machine and I want that sweet sound back.

This car's mileage dropped off some time ago. I've been working on it. (25% reduction in mileage.) The noise I heard in the valve train could have radiated and it was very likely it was valves several degrees off. (It's amazing... even in cruddy condition, these engines still run.)

If you are familiar with these cam idler bearings, there's a little metal bracket (with a spring) that sets the preload on the timing belt. There's a small metal tab that fits into the center of this bearing. That finger had broken off, so the bearing was free to back off.

The noise I was hearing in the cover was the timing belt "eating" the cover, as it flopped loose back and forth. The noise I heard elsewhere was likely the valve train jerking itself around. (And yet, the car still had lots of power.)

The bolt holding the bearing down was only finger tight. (It was tightened down well when I put it together last time... so either condition could have caused the other.)

The idler bearing isn't noisy and it's nearly as tight as the $50 replacement unit. It's still going to be replaced. (BTW, if ya'll replace these units, you might check with NAPA. They have Gates belts, which are superior IMHO to the Mexican made ones, and you can buy a kit of bearing/belt for less money than you can buy the seperately from anyone else. Unfortunately, I didn't get the kit because I thought I'd have it back together today.)

I assume these adjusters are going to be dealer only, with their several day wait. If anyone knows a good source for one, please let me know.

Oh, and following advice here, the waterpump has been replaced. The original wasn't in bad shape (slight rust on the impeller) but it's not worth taking everything apart again to save $30. It probably had another 40K miles in it, but *all* this stuff is mounted on that unit. (A bad design, IMHO. They could have made it 2 aluminum parts and saved owners bucks. Oh well, a $400 dealer bill once every 100K miles isn't too bad a deal, eh?)

If I remember right, there is a dot on the rim
of the timing sprocket, and should be at the
top when it all goes back together.

That would be TDC firing #1 on the distributor.

The FSM is very clear about this, and if I recall correctly, the Haynes manual is actually WRONG - if you follow Haynes, you'll probably get it 180 degrees out  .

I just can't remember which things line up with what.  It's four marks - two on the sprockets, and two on the block.

Don't know if this is true or not but I've read that a Zook should sound like a sewing machine. If not, the valves are set too tight and you risk burning a valve. It's a fine line between tight enough and too tight. Many of them also suffer from piston slap, as mine does, but it doesn't seem to affect longevity.

TN_T

     I think I have piston slap too but not sure.  Mine reminds me of a diesel when its cold cause it rattles so much.  Its lots worse when I'm accelarating.  Gets much better after its warmed up.  Sound like piston slap?  How do I know for sure?  (16valve)  

     I think I have piston slap too but not sure.  Mine reminds me of a diesel when its cold cause it rattles so much.  Its lots worse when I'm accelarating.  Gets much better after its warmed up.  Sound like piston slap?  How do I know for sure?  (16valve)  

Yep, you have the same symptoms as mine. If it's cold outside my 16valve must warm for a few minutes before driving our it sounds terrible. After some research I'm changing from Valvoline MaxLife 10w30 to Pennzoil Long Life 15w40, it has a huge amount of Moly which is known to help quiet things down a bit. 15w40 would only be suitable for warm weather though. I have also discovered that a Motorcraft FL400S Oil Filter has the same dimensions as the OEM Filter except it is slightly longer, more capacity, so I'm also considering that filter. If any of this helps I will post the results.