Timing chain on a 1989 Chevy S-10, 4.3 V6


I have to replace the timing chain and will also need to hand crank the engine to set the timing. I have a rough idea on setting the timing, (#1 cylinder to TDC) but don’t know any of the specifics. Any help, guidance, Do’s and don’t do’s would be greatly appreciated on replacing the timing chain and setting the timing. I’ve got the radiator, fan and water pump out. The pulley and timing chain cover are still on. Thanks for all your help.

Nick J.

One thing you’ll want to do is to replace both the cam and crank sprockets along with the chain. Everything wears together as a set, and thus should be replaced as a set. You’ll need a puller to get the crankshaft sprocket off.

The sprockets have timing marks and are keyed to go onto their respective shafts only one way (just make sure they aren’t flipped), so once you get the cover off you’ll want to turn the engine by hand until the timing marks line up, and then leave it there as you remove the old chain/sprockets and install the new ones. Once the new ones are in place, check to be sure the marks still line up and then turn the engine by hand through one full revolution, checking again to be sure the marks stay lined up. If all is well, close everything up and start 'er up. It’s not a bad idea to change the oil soon after you do this.

I recently did this same job on my '96 S-10 2.2L, and it really wasn’t as bad as I thought it would be. The toughest part was prying the timing cover out and fitting it back into place; chain and sprocket removal was pretty easy.

I believe this engine has a harmonic balancer on the crankshaft, not a pulley. If so, you need to pull the harmonic balancer off the crankshaft with what else? A harmonic balancer puller! Most part stores sell an inexpensive puller for this job.


I’m not a mechanic by trade but I’ve been busting my knuckles on vehicles since high school (40+ years) and I am seldom without a manual for the vehicle at my side. A Chilton, Motor or Haynes repair manual will walk you through most anything you would want to do. Haynes are available at book stores or auto supply stores (and on Amazon too) for about $15, and all are available at the public library. Any of those would have allowed you to finish the job without washing up and punching computer keys.

the balancer is the pulley.

or we may have an issue. like broken cranks,miss fire codes,resonance, ect ect ect.

hate to be me,but do you have a cape?

A small edit: Most 4.3s will actually have a harmonic balancer AND a pulley in front of it. Make sure you use the right puller (as stated above) and not a claw-type puller.

After you do timing chains a moderate number of times they do(as most things in life) get easier. I dont want to discourage you but this is a job that has more than just a little potential for going wrong. I my opinion you need to be more than “just a little bit mechanicaly inclined” But the job is possible for the DIY.

Autozone has an online manual for the 83-93 S10. Here is the section on timing chain replacement.


If the link does not work, just enter the year, make, and model for the repair guide.

Not a job I would tackle, but good luck.

Ed B.

All timing chains like yours can be installed without setting the timing marks on #1 TDC. There are timing marks on the sprockets. Maybe the marks line up better by doing that first but I never bothered. I never had any problem moving the crankshaft or camshaft into position on that old style of engine. Of course, doing whatever the manual says to do is best. That engine should be really easy. Wish I were there, I like coming in after most of the work is done to grab some of the glory.