OK... 1989 GMC 1500 with 305. There is a weird ring coming from right around the flexplate. kinda like having a marble in your hubcap. mot when engine is cold but after a couple of minutes. Took the cover off to see if they were hitting still there. Inspected for loose bolts cracks. Nothing. disconnected torque converter, still there. removed tranny, still there. removed flexplate, cannot start engine to see if still there. no cracks, broken welds in plate but if I hit it with a wrench like a dinner bell I can detect a faint rattle. suspect it may be the ballance weight. I mean FAINT rattle but rattle none the less. None of the tack welds on the balance look broken. I was thinking of packing JB weld or something under the balance to secure it. Any better ideas? How sensetive is the plate to minute weight changes.
08-14-2005 02:33 AM
I'm not sure about the weight issue, but I would question the strength of JB weld in this application, you might be better off to weld the balancing weight, at least you would know that it will hold
08-14-2005 04:29 AM
liquid weld has its place but i would not use it there either.you could go to the junk yard to get another one or racers outlet at ebay motors has an extra thick scat sfi approved 305/350 168th flex plate for 40.00.i spent alot of money with those people last winter building a new 406 i could run regular gas in and they are good people.i saved alot of money with them and bought one for my 406 just to avoid that problem.good luck
08-14-2005 07:15 PM
Well I tacked up the weight and threw some welds around the ring gear but the noise is still there. After supper I am going to look a bit more. I can't find any indications of metal/metal contact. Could the flexplate be too flexible?It doesnt look like its floping around or anything.
08-14-2005 07:36 PM
It sounds like your starter is letting the pinion gear touch the ring gear. Try putting a SMALL shim under the starter and see if the noise goes away.
08-14-2005 09:45 PM
I was under there while it was running and I can't see any contact at the starter or anywhere. its probably something real easy. i'll try a shim and see what happens.
08-15-2005 02:35 AM
Well that was fun. Scolman was on the right track. Didn't need a shim on the starter but I did need the solenoid return spring that was sitting on my workbench. I rebuilt the starter last week and seem to have forgotten it. The bendix wasn't pulling back far enough and was contacting the plate. Didn't look like it while it was running but I guess it doesn't take much. Please don't post this on the internet or anything I feel a bit foolish. :spank: