Motor Mount Questions

[Bert]

Nitrofarm's pics of the braided f;ex pipe install on an Aspire correspond exactly to where the Cat on a Festy is located. The car won't pass an emissions test if I do that. However I sure like the idea and will tangle with something in a similar vein sometime.

[JohnGunn]

"Normalizing" is something I've never bothered with, because the only time it seems like it would apply is after things have gone off kilter to begin with.

My point is that the things that have gone off kilter may well be unbalanced stresses on the mounts that can be reduced by normalization.

[JohnGunn]

John the best way to do this is with a engine hoist.Loosen ALL attach points,but don't remove the nuts.(Having all the weight of the eng/trans on the hoist) The goal is to get the motor/trans "Squared up" in relationship with chassis. The engine mount on the RH side gives lots of room for this. Once the engine is where you want it.Lower it back down.And start by tightening these 3 nuts first. ... Good Luck & Happy Holidays.

Thanks for these helpful comments, nitro.

When I discovered that relatively little of the weight of my engine was being supported on the front mount, I tried to imagine how a balanced sharing of the load would have been established at the factory. I imagined the engine being lowered into the engine compartment at the factory. Then I saw the three through bolts inserted and the full weight of the engine allowed to come to rest on them. Then they would have been tightened to specs. After that the catalytic converter would be attached to the flange of the down pipe and tightened at the angle which would place the least amount of stress on the engine, thanks to the donut shaped gasket and the springs under the flange nuts.

What you have suggested is more in keeping with the way it must have been done at the factory, and would be better in that you wouldn't have to drive the car around to get the engine to settle into its lowest, most balanced, position.

I don't know much about the history of my car before it came into my hands. But its low mileage, 75,000 miles, and all appearances indicate an absence of any extensive repairs.

I do know that the front and rear mount through bolts had been greatly over-torqued. I spend a couple of days soaking them with PB Blaster before I could work myself up to the point of applying enough force to break them loose. I figure one of the two previous owners had taken it to a mechanic and that he had done nothing more than tighten the through bolts to an excessive amount.

My guess is that they had become loose and the stress of hard accelerations had twisted the engine into a position where most of the weight of the engine was resting on the rear mount. Seeing that the bolts were somewhat loose, he had merely tightened them down supper hard, essentially making the current imbalance permanent.

Of course all of that is merely my speculation. The thing that is not speculation is that normalizing the position of the engine, as I have described here, worked to essentially restore the proper weight distribution of the engine on its mounts.

Thanks for the Happy Holidays wish. They should be if reception is good, the games are close, and the underdog always wins.

[Movin]

I think you are "over killing" with your method to obtain equal stress on rubber mounts. It is important, any rubber suspension components have to be torque equalized as well. It shouldn't add any time to the R&R just a little thought while doing the job. Its amazing how something old loose or installed wrong (torque loaded) will severely accentuate something else like a flywheel and pressure plate that needs resurfaced.

[JohnGunn]

I think you are "over killing" with your method to obtain equal stress on rubber mounts. It is important, any rubber suspension components have to be torque equalized as well. It shouldn't add any time to the R&R just a little thought while doing the job. Its amazing how something old loose or installed wrong (torque loaded) will severely accentuate something else like a flywheel and pressure plate that needs resurfaced.

Thanks for joining in, Movin.

I'm not sure what you mean by "over kill," but as I was writing the procedure I followed, it occurred to me that I was doing a lot of things which were not essential to the normalization. For example, removing all nuts and bolts to clean and put anti-seize on them for re-torquing, might seem "over kill" to some, but for me it's just me doing what I think best.

It also occurred to me that it might have been enough to loosen only the through bolts before driving around to allow the engine to settle into a balanced position. But it seemed to me that to get the best balance I should loosen all the nuts and bolts involved in supporting the engine. So that's what I decided to do.

So, whether "over kill" or not, this is the only procedure I used, and, therefore, the only one that I can be assured will produce the kind of results I achieved.

One of my most deeply held beliefs is that everyone should be allowed, and even encouraged, to follow their own lights, even if I think they are mistaken. In the end, what counts, more than just results, is what makes you content and happy with your work and yourself, no matter what you or I or anyone else may think.

[Safety Guy]

Taking off the crossmember bolts & nuts, cleaning the threads then applying anti-seize is a very good idea, IMO. On my 1991 AquaMutt's rebuild, one of my two front bolts turned out to be stripped and I had to drill through the lower crosspiece and install a long bolt and nut to replace it. (I know this has happened to others as well.)

On our old cars, almost anything that could get corroded or bind should be cleaned and have anti-seize applied so you don't damage the threads, break the bolt, or spend so much time using PB Blaster and heat, etc. to get stuff off. This is doubly so because most of us don't see our little cars as "disposable" so we want to take care of them.

John, a method kind of like you used to "normalize" your engine NVH is described in the shop manuals. Whether or not you did more work than you needed to, you did fine and your results speak for themselves.

Karl

[Movin]

Overkill was a complement, you went beyond what a dealership flatrate person would have. The flatrate job will last through warranty with satisfactory results for the average owner. Your efforts are above average which is why we do our own work where possible. Good job. Just don't forget the flywheel and pressure plate.

[JohnGunn]

Taking off the crossmember bolts & nuts, cleaning the threads then applying anti-seize is a very good idea, IMO. On my 1991 AquaMutt's rebuild, one of my two front bolts turned out to be stripped and I had to drill through the lower crosspiece and install a long bolt and nut to replace it. (I know this has happened to others as well.)

On our old cars, almost anything that could get corroded or bind should be cleaned and have anti-seize applied so you don't damage the threads, break the bolt, or spend so much time using PB Blaster and heat, etc. to get stuff off. This is doubly so because most of us don't see our little cars as "disposable" so we want to take care of them.

John, a method kind of like you used to "normalize" your engine NVH is described in the shop manuals. Whether or not you did more work than you needed to, you did fine and your results speak for themselves.

Karl

Thanks, Karl. I'm always happy to read anything you contribute, even should you not agree with me. (Could this be a way to define the word respect?) But it's more than just agreeing with the things you write. Both your ideas and the way you express them find some illusive resonance in me.

Had to look up the meaning of NVH. "Noise, Vibration, and Harshness" for anyone else as uninformed as I.

Although the idea makes good sense to me, I can't take full credit for it. I think the first place I saw reference to it was in our Haynes Manual, page 2A-18.

Here's what it says:

"19. If, after replacing the engine mounts, there is some noise or vibration that wasn't present before, you may need to "neutralize" the mounting bolts. Loosen the transaxle mount nuts/bolts (the ones to the crossmember) about three turns each.
20. Without driving, shift the transmission into gear, then shift into Neutral and finally, shut the engine off. Now tighten all mounting nuts/bolts to this Chapter's Specifications."

Of course, I created my own procedure. For one thing, their instructions seemed to indicate they were thinking of a car with automatic transmission. But, most of all, they failed to mention the importance of "neutralizing" the position of the mounts on their through bolts.

This was one of the most dramatic improvements in drivability I can remember seeing. And, so far, the improvement is holding well.

[JohnGunn]

Overkill was a complement, you went beyond what a dealership flatrate person would have. The flatrate job will last through warranty with satisfactory results for the average owner. Your efforts are above average which is why we do our own work where possible. Good job. Just don't forget the flywheel and pressure plate.

Movin, thanks for clearing this up. Glad to learn you had correctly understood the motivations behind all that I did.