First, i figure that this is more suitable here, than in the tech section, as i dont have the problem (really) anymore, but i might in the very near future.

Second, this will probably be pretty long.

My problem started waaay back in october at Uwharrie. As soon as i got off the last trail of the day, i noticed an odd sound coming from my engine bay. Only made the noise while under load (in gear, on accelerator). Not in idle, not while coasting, not even while coasting and in neutral and revving the engine. It started off not too bad. It kindof sounded like maybe an exhaust leak. I complained about it over the CB and they reminded me that i HAD hit my cat on an obstacle on Falls Dam trail. I was worried, but as Joe Darlington later told me, the only thing i could do was wait; if it got better, it got better, and if it got worse, just get it worked on...loosen up and stop worrying about it. Good advice.

I took it home, waited a week, and my problems started to worsen. I started having this terrible trouble getting it started. I would have to sit there, flooring it, attempting to get it to start. It made two different noises while trying to start.
1. The engine sounded like it was trying to start. It sounded like the starter was turning the flywheel, the flywheel was turning the crank, but there was no spark, and there just wasnt that sound that is supposed to be there when you crank your car. That yin-inna-yin-inna-yin-inna sound. It wasnt there.
2. Right before the car cranked, it sounded like the starter was straining agains about a thousand pounds per cylinder to get the pistons to turn over. The starter would drain almost all the juice from the car, making the lights dim on the dash. Finally it would come to life. Drove it to school that day.

At school, we were having a half day. (teacher grading day or something--im in highschool) Me and some friends were going to downtown Athens to get lunch. I attempted to start my truck. Wouldnt crank. Tried and tried and tried. Finally cranked. Drove up to a friends car to get a CD and got out to talk to him. But not before i cut off the truck <img src="/forums/images/graemlins/angry.gif" alt="" />.
Get back in. Try and Try and Try to crank it. Finally cranks, but instead of the instand VROOM! I'm used to from my having to floor it to start it, i get a vrrrrooooooooooooooomm. Like instead of an instant jump in RPMs, i get a slow motion version, where it is struggling to get up to 3000rpms. The power from it isnt even enough to move the truck. I get out, open the hood and start jiggling vacuum hoses. The one coming from the PCV is out about 1/4", so i push it back. I jiggle/push other ones back to where they are supposed to be. Finally get back in, and it cranks(after trying and trying, etc) and it is back to its old self.

Drive all the way to Athens, and go to my Dad's office, to tell him about it. I come back out, (with a truck load of hungry teenagers)and try to get it to crank. Dad comes out, and looks at the engine, and this time it cranks right up (its like magic vision or something). I start to drive off, and i notice the NEW sound. Horrible valve chatter. The most horrible chatter ive ever heard before. I drive through athens, drop my friends off, and head home, fearing that i wont even make it there.
I make it home, and park it for the next few weeks. After i save some money, i put in a new tank of gas, as dad figures it might have just been a bad tank. That didnt help. (He used to have bad chatter in his Triumph when he didnt put good gas in there) I took it to my mechanic, fearing the worst.
My mechanic calls with good and bad news.
Good: One of the main problems was with a split $1.29 vacuum fitting. He was able to diagnose and fix that for free, other than the part.
Bad: Apparently my timing chain started to jump teeth, and therefore, jump time. He said it was off by as much as 7 degrees!

We get there, and he has replaced the entire timing chain set for 100 in parts, and 120 in labor, plus a 50 dollar valve/sensor that i had screwed up a while back. (50 bucks???) It was at least an entire days worth of labor between the timing and the diagnosis. My mechanic is great.
What is wierd is that we only replaced the timing chain about 40-50,000 miles ago. the last time, it actually broke on the highway. My mech says it was a miracle it didnt kill the trooper then. Anyway, he says that it is the kind of driving that i do, both on and off road. Now, i shift somewhere between 2 and 3000RPMs in everyday driving, never exceeding 3500 except in 5th gear on highway at 75mph. Offroad, i never exceed 4500 even on really bad hill climbs.
So, i have now adjusted my driving style,(never exceeding 3000, and shifting much much lower) but i am still getting some valve chatter, now about 100 miles after the repair. It came back very gradually, but it is there. Not nearly as bad, and doesnt make the loss of power like it did last time ("power" in the troop has never been better!) but still very annoying, and very worrysome that it might come back with a vengeance.

My only real questions are:
Is this common?
Is there anything that i can do to keep it from happening?
If it DOES happen again, can i replace the chain/gear set from a 3.1 to make it a little more heavy duty, or is there a more high performance option out there?

The type of wheeling i do (lots of muddin down here in the south) i like to be able to spin my tires while in the dirt. I know its not a high horsepower machine, but 4000 RPMS is NOT that high, and i really feel like i shouldnt be having this problem.

Thanks for reading. I know its really long.... any comments or thoughts you have would be welcome.
-J <img src="/forums/images/graemlins/kewl.gif" alt="" />

Did the mechanic put in a new timing damper? Or does it even have one in there at all??? <img src="/forums/images/graemlins/confused.gif" alt="" />

If it's missing or was not renewed the last time, it could very well be the reason for the early failure and problems you're experiencing now.

The damper is metal and has rubber 'slippers' bonded to it. It's bolted to the block and resides in the space between the cam gear and crank gear. It serves to stabilize the timing chain and when the bonded rubber parts get old, they break off and fall in the pan. Then the chain rides metal-on-metal until it wears thru the damper, catches on a sharp edge, and instantly snaps.

My LS 2.8 Trooper (now a 3.4) was dead like this when I got it. Replaced the timing set and damper and it was fine.

So, ask the mechanic if he put in a new timing damper and if he goes "Huh?" you know what the problem is!!! <img src="/forums/images/graemlins/drunk.gif" alt="" />

Throw a timing light on #1 plug wire and see if the timing is stable. If it jumps around, there's a problem. Wiggle the crankshaft to and fro a few degrees and watch the distributor rotor. If you see more than a degree or so of crank slop before the rotor moves, there's something going on.

The 2.8 in my other old Trooper has almost 170,000 miles and it has around 3 degrees of slop. Due for a R&R sometime in the near future! Still runs OK though, the retarded cam timing gives it real good top end!!!!

HTH & G'luck.......ed

I will deffinitely call him up and talk to him about it.
However, this time, it didnt snap. That was last time, around 40,000 miles before the last one. THIS time, it simply started to slip off the top timing gear. He said it was only a matter of time before it snapped.
I will ask him next time i see him. I might be finding employment there anyway, in the form of a floor sweeper/go-fer. <img src="/forums/images/graemlins/smile.gif" alt="" /> Thanks <img src="/forums/images/graemlins/kewl.gif" alt="" />

Who else has had this problem, and again, would the 3.1 chain/gear work?
-J <img src="/forums/images/graemlins/kewl.gif" alt="" />

Personally I think the mechanic is full of it! <img src="/forums/images/graemlins/rolleyes.gif" alt="" />

I ran the tar out of the old Trooper and it's still going at 170,000 miles. This includes excursions to redline and towing 2500 lbs of ski boat/trailer. I did not baby that motor in the least and it's still a Survivor!

No way a new chain is going to break or even stretch enough to slip that badly in 40,000 miles unless there's something else wrong. Cryin' out loud, it's a double-row chain running in an oil bath!!!

Either something was wrong with the installation or poor quality parts were used.

The 3.1 or 3.4 timing sets are no different than the 2.8's.

I believe there are heavy-duty full-roller timing sets which are stouter than stock, you might check into that.

Maybe Jegs or Summit or other aftermarket sources. The timing damper is cheap (under $10) and I don't think it much matters where you get that as long as it's a name brand.

G'luck........ed

I trust my mechanic 100%. Hes been in business for 25 years, and he is the only person we have ever taken the trooper to. Hes always treated us very well, and provides great service. He does the timing on the trooper by ear, and it is spot on every time. I dont doubt that he knows what he is talking about, but if the timing damper wasnt installed, or if it didnt come with the kit, i wont blame him. Ill just buy all the parts next time, and know what it takes to fix it.

I will definitely look at summit and jegs. I should have thought of that sooner.
Thanks,
-J <img src="/forums/images/graemlins/kewl.gif" alt="" />

Summit shows a Cloyes True Roller timing set, CLO-9-3137, for $93.88.

Jegs, P/N 220-9-3137, $93.99

BTW, to properly adjust timing on a GM TBI-equipped vehicle with ESC (Electronic Spark Control), you have to disable the ESC or it's impossible to get an accurate reading.

The ESC wire in a Trooper 2.8 is under the front tray in the center console and is the only wire in there with an inline quick-disconnect. You undo this wire, then the timing can be checked/set.

One last thought, if the crank gear was not replaced and only the timing chain and cam gear done the last time, this would accelerate chain wear. I'd definitely insist on all-new components, and the H-D timing set like that Cloyes should be quite durable.

Here's a link I found to a standard Cloyes timing set and damper:

https://secure7.nexternal.com/share...CategoryID=2&Target=products.asp

Also found this little tidbit on a site devoted to the Citation X-11:

"Cloyes True Roller - 9-3137 $85 (preferred) The stock chain dampener is not used."

Guess that's something good to know, I'd certainly confirm it to be true or not upon assembly. Might be something about the true roller chain that doesn't work with the stock damper.

G'luck.......ed