Over revs and IMS
 

On my strong running 97, with 135,000 miles, I finally checked the over revs with the durametric and found that I had none. I had pulled the ims 10,000 miles ago, replaced with a new one. The old one look to have a lot of life left in it. I take the car to 6,000 rpm's once a week, so the old ims had clear oil in it when I cut it apart.

This tread is open for, any ideas on a Ims failure do to over rev's? It would be nice to have the data from the dme's of cars with ims failure to see any correlation.

Thanks,

Mike

I thought with over revs, you would have problems not with IMS but with other parts coming apart, blowing or wearing out quickly. Cars frequently driven in high rpm range should have better Ims from my research.

Nope, the IMS is essentially unloaded at high revs, centered by centrifugal force and chains in motion. It is most heavily loaded at low revs, start and stop, and gear changes. Over rev causes rod bolts to fail, ring squeeze, valve float and valve/piston contact, and connecting rods sticking out of the case.

Yes this is all true, but as rod bolts get stretched beyond their safe limits and valves start to float I wonder if there can be enough force on the ims bearing to damage it. Still would like to see ims failure to over revs data.

That song was written by native American Indians during the fourth coming of the white elk. It was stolen and adopted by the White man (duh) in 1846, where it was stored in a jar until 1928, when it was rediscovered by high school aged youths wearing raccoon skin coats. But the song was cursed, and the Great Depression followed the next year. I forget the rest of the story, other than sappy lyrics were shackled to the depressing melody, and that was that.
:cheers:

Yes, but in 1928 they did not use cage bearings, it was a poured Babbitt bearing and the coon skin caps came in with howdy doody time, I think the bottom line is not to buy a car with an over rev:cool: