06-03-2007, 06:27 PM
MWrenchEngine isolators
Hopefully this is the last change/update that I will have to make before the trip on Tuesday!!
While replacing the muffler, I noticed that the rubber isolators attached to the bellhousing seemed a bit compressed, I talked to Spartan and by the VIN sent me 2 new isolators. Turns out that mine had a different size isolator then what is called for on Spartan's build sheet. The old ones are 729 isolators and the new ones are 730, a bit bigger. After talking at length with Spartan I decided to try to use the new isolators as it seemed these would hold the weight of the 6 speed better then the smaller ones. The height dimensions (729 vs. 730) were very close just the diameter and 2 mounting bolt hole locations were different. As luck would have it, the center hole in the frame bracket was large enough to accommodate the larger isolator and all I had to do was clock the new isolator to a new position and drill 2 new holes. The center bolt was 5/8" on the old one and 3/4" on the new one, just had to drill out the engine bracket and washer, get new grade 8 bolts and I was all set.
Old isolator:
New isolator installed:
Old isolator and engine bracket:
Old and new isolators:
New holes drilled:
New isolator showing how it is clocked:
Installed:
The old isolators were compressed at least 3/4" down from spec and this was with out load, the rear of the transmission is 1.2" higher then it used to be, the drive shaft angle is now on spec to the Spartan spec, it will be interesting to see if any change in noise or vibration will be felt after this change.
This was not a bad job at all the only difficult part was drilling the chassis brackets but even that was not bad, total time was just under 3 hours including breakfast break.
06-04-2007, 01:07 AM
olroyIf you had drive train vibration before, there's a pretty good chance things will be improved by straightening out the drive shaft.
06-04-2007, 11:08 PM
RustyEd, it seems like some of us (I ain't callin' names, here) spend an awful lot of time
under our Barths...

06-05-2007, 12:41 AM
MWrenchYup, is it labor of love? Not quite but close. I do enjoy working on the Barth but will have to get back to some other projects soon, My BMW/Corvette engine conversion has been calling and there is a major house repair that I must attend to before rainy season starts in October/November.