I started getting a vibration in the rear about a year ago.

So I balanced the tires. Still there, but it came and went, and was barely noticeable, so I lived with it.

It got worse, so I had the tires re-balanced. Still there.

Had the tires balanced again. Still there. A couple of months ago I noticed unsual wear on the right rears covering about 60° in the same place on both tires, and one wheel had about 3/16" lateral runout, so I replaced it and the tires and put in balance beads on all four rears. Still there.

The shocks were weak, so I replaced them. Still there

I had the left rears pulled, and noticed a small stone had imbedded into one of tire's the grooves and had severed at least one belt and damaged a second or third. Replaced the tires. Very little change.

Earlier this week, I replaced the water pump, because there was dripping from the weep hole; I was none too pleased, as the engine had <30K miles on it. Removing the fan to get to the pump, I saw notches in the blades where they had rubbed against the steel shroud. At rest, there's at least 5/8" clearance.

This could be caused only by bad motor mounts, so I checked them, and the left was toast, and the right, none too good.

I had the motor mounts replaced, and the problem seems cured; apparently driving at certain speeds started a sympathetic vibration in the engine, and it was bouncing.

I don't know if the problem's really fixed (I've thought that before), but it seems to be.

EDIT: I added link to a source for HD motor mounts in this thread.

Have you checked the ground wires on the tires?

Nick

Dang, NO! And that was the first thing you mentioned last week...

Better check your muffler bearing while you are at it.

speaking of muffler bearings.........in the process of dismantling the 29 ft. '77 MC I came across a whole bunch of them and set them aside. Anyone who needs some can have them if they come and pick them up (they're too hard too ship) if I can find them again.

Dick, I would like to install dual exhaust with a couple of smitty's on the 3208 cat. Can you save me a couple of the muffler bearings and I will pick them up when we come to the DC GTG.

Thanks
Nick

P.S. I will need one left side counter clockwise rotating bearing and one right side clockwise rotating bearing.

would they be Timken rollers in the thrust position?
lenny

still don't know where shower water goes? lenny

quote:

Originally posted by lenny and judy:
would they be Timken rollers in the thrust position?
lenny

I went to Muffler Bearing School at Boeing. They said use only TAPERED roller bearings in that application.

quote:

Nick: I would like to install dual exhaust with a couple of smitty's on the 3208 cat.

If you do that, be sure you back off the advance curve to prevent preignition.

With dual exhausts, one is held on by standard threads, the other with left-hand threads, so you'll need a left-handed wrench.

I made those also they came in handy when we sent to NAM
to fix the m16.
lenny

Aww! tuff luck, Nick these were connected to dual cherry bombs attached to the '77 454 gasser. ....doesn't preignition on a diesel make you go backwards? and M14, M17 ...could never replace the M1 Garand. I have a combination box wrench, one end right hand the other left. I think Bonney used to forge them.

....PS shower water goes down the drain!

PSS. DUH!

I just checked the manual, these bearings are mutiwrenchinal, they only need a quarter turn either left or right, it said something about bayonettes and breach blocks but I didn't understand that. I tried to post the manual but my scanned ate the original. ............go figure! Oh! Oh! I have a drink for you.......beer drinkers:..... 1 part Yuengling Dark-Brewed Porter, 1 part Yuengling Premium Beer (Yuengling Original Black and Tan), 2 parts Yuengling Lager. Blend carefully in a very tall glass or mug or stein to avoid foaming over. Sip, drink or guzzle at temperatures over 43 degrees and under 50 degrees. reeefreshing! to recap 1 can half and half and 1 can lager. (or bottles) warning! no frosted glasses or any of that "ice cold beer" crap from Florida and those other southern places.