Buzzing/vibration from dist cap

[S10SNODOG]

2003 CHEVY S-10 VORTEC V-6 4.3 156,000 MILES I GETTING A VIBRATION/BUZZING THAT IS DIRECTLY RELATIVE TO THE INCREASE OF RPM/THROTTLE AS I GAS THE TRUCK IT DOES SEEM TO GET LOUDER TO A POINT BUT DIFFENTLY CHANGES THE SOUND OF THE BUZZ OR VIBRATE I DID TAKE THE CAP AND ROTOR OFF AND CHECKED THEM .... CLEANED THEM THAY LOOK GOOD TRYED TO SEE IF THERE WAS PLAY IN THE SHAFT BY GRABING THE ROTOR STILL ATACHED TO THE SHAFT AND TRYED TO SEE IF THERE WAS ANY PLAY NOT MUCH ....CLUELESS PLEASE HELP HERE A DIRECT LINK TO A VIDEO OF IT THANK YOU FOR LOOKING ANTHONY http://s293.photobucket.com/albums/m...-44-28_759.mp4

[old_master]

Most likely a worn distributor drive gear or bushing. It's caused by the distributor not being installed "plumb" in the bore. The inside diameter of the intake manifold bore is larger than the outside diameter of the distributor housing. This allows camshaft retard to be adjusted. Dorman makes a new design aluminum distributor, stay away from the plastic ones. After replacement, perform the crankshaft position sensor relearn, and then check and adjust camshaft retard, (both require a high end scan tool). If you just replace the distributor, the same thing will happen to the new distributor. When you cleaned the terminals inside the cap, you removed the silicone dielectric grease. When the cap is replaced, a dab of silicone dielectric grease is applied to each terminal. When the engine is running, the electrical current passing from the rotor to the cap crystalizes the grease, (it's supposed to be there).

[S10SNODOG]

the only thing is I DONT THINK the dist. has been touched since CHEVY put the motor together in 2003 I had the cap and rotor replaced by a service tech. about 20,000 miles ago, but would there be any reason the service tech. would pull the complete stem,cap& rotor. if not then MAYBE the stock bushing/bearing on the shaft is going at 155,000 miles that would almost seem normal ..........I dont know I'm tring to figure this thing out MAYBE I can just buy a new good QUALITY STEM,CAP,ROTOR AND PUT IT in what do you think! I just need to get 20,000 - 30,000 more miles out of this truck IF possible YOU GUYs know best I'm just tring to give you all the info I can.............. I need this truck for transportation ......thank you very much in advance for the HELP ! TY.

[old_master]

At 155K almost anything is possible. Could be it was installed that way when they built the engine, stranger things have happened The distributor does NOT have to be removed to replace the cap and rotor. You can check the gear easy enough by removing the distributor and looking at the gear. Before you pull the distributor out, remove the cap and bump the starter until the rotor lines up with the "6" on the distributor housing.



Then remove the distributor and check it. When you install the distributor, make sure the rotor is pointing at the "6" when it's fully seated. DO NOT engage the starter while the distributor is removed.

[S10SNODOG]

ok I do have 1/4 " play side to side I have picked a new dist. just the core and i'm comparing the play they both have a little pull up play like 1/4 inch but on the on the truck you move side to side pushing down NO PLAY but if you lift 1/8 "and side to side YOU GET 1/8" SIDE to SIDE PLAY the new one has NONE so I'm betting thats where the noise is coming from .........any pointers would be great I will follow you inst. and will lube up the gear end that meshes with the cam with assembly lube

[old_master]

Post #4 explains how to replace the distributor making sure the engine is timed correctly when reinstalled. When bumping the starter, have an assistant watch the rotor. When it starts getting close to the "6", disconnect the battery negative terminal and use a socket and ratchet on the crankshaft dampener bolt, making sure to only turn the crankshaft in a clockwise direction. If you pass the "6", do not turn the crankshaft counter clockwise. By turning the crankshaft only in a clockwise direction, it keeps any slack in the timing chain on the passenger side of the engine, (that's where it is when the engine is running). Any questions, just ask.

[S10SNODOG]

OK done deal and she STARTED GREAT RAN WELL thanks to you guys im feelling on top of the world LOL .... just for techinal sake what's the torque value on the 10 MM bolt that holds the dist. down ? and out of left feild should I have my timing belt changed or will they go 170K no problem I fiqure the Hyundai motors have a belt and they should be changed at 60k why you would think a chain should do at least double but I M NOT SURE .?.. again thank you so very much for all the help I hope this thread helps someone out

[old_master]

Good job, glad you got her fixed, and thanks for posting back. Distributor hold down bolt torque spec is 18 foot pounds.

The 4.3L has a timing chain and with regular oil change intervals, the chain will go a long time. I service a fleet of 4.3L's ranging from 200,000 miles up to 360,000. All run strong and none have had the chain replaced. Timing belts are a different story, check the owners manual for recommended replacement interval. A belt will never outlast a chain!