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Discussion Starter #1 (Edited)
I ordered the part from SJS, opting for their aftermarket part in steel. After reading a number of posts about that part breaking, as well as inspecting the old part while still on the car, it seems that the factory part was not very durable. It broke at where the part necks down to the chassis mount.

IMG-4631a.jpg


The SJS part was nice, about 2.5 times as heavy, but I had to enlarge one of the holes nearest the chassis mount, in the direction of the red arrow in the photo. Not sure if any distortion occured on my transmission case, but the same hole on the original part is a little larger, hence my need for the slight mod. I used a Dremel tool to abrade the material until the other two bolts easily threaded in.

When removing the bracket, I had trouble holding the head of the long bolt where it attaches to the chassis mount, being just above the suspension pivot, so I removed the mount still attached to the bracket by loosening the small 12mm headed bolts and nuts. Their bottom nuts were easier to access, but I had to reach in creative ways to get at both of them to remove. Note: that bottom transmission bracket bolt is a devil; I could not reach it on the broken part until the chassis mount was removed (separately, as it was broken), and once the top bolts were started, I could not tighten it much more. I had to lift the transmission a bit with a jack to keep from compressing the rubber mount, which kept it a narrow as possible. When the jack was released and the load placed back on the chassis mount, it did bulge a small amount, likely enough to interfere with getting a socket in there.

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Here's the part installed, didn't think about the dissimilar metals until now -- anyone think this might be a problem? I took a couple of other photos of things I need to replace such as the bellows on both shift cables. I also removed the hose from the coolant header tank to the expansion tank, blew into it, heard bubbles blow into it, then coolant blew back through the hose when I stopped blowing... not sure why it did that. I thought the overflow tank was not closed to the atmosphere.

My Quick Jack arrived this week but I was too sick until today to unbox and assemble it, no doubt it would have made this job a lot easier. I did have to remove the rear storage shelf to get access, but that was not too difficult. I would rate this a 3 out of 10 in difficulty, the danger of damaging the threads on the transmission case were the major scary parts, but most of the rest is very straightforward.

My thanks, of course, to LT for providing valuable info before I dug into this, I hope this can be the first of many contributions from me.
 

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Wingless Wonder
1988 Esprit Turbo
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5,861 Posts
Thanks the write up, the pictures helped, too!

Did you know your old mount was broken before removal? If so, what was the symptom? Ours were fine at 76K miles.



I don't worry that much about dissimilar metals...I always use a coat of anti-seize on most hardware when I put stuff back together. (Not on things that require exact torque values on assembly)

I've seen and have heard of loose engine and transmission mount hardware. Now I check those bolts yearly. (The RH engine mount provides engine ground too, so that is doubly important!)
 

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Discussion Starter #3
After the engine warmed up and the idle has dropped, I heard a hollow ringing that I thought was an exhaust pipe rattling. When I took it in for that USA dealer complimentary inspection back in December, they showed me the cause was the bracket. I did not have too much trouble shifting, only had a little trouble getting reverse at times. I’ll need to check the specs next time do some work.

One aspect of the car that I find alarming is the amount of corrosion on many of the fasteners. For an island nation that is known for cold and humid conditions, I can’t fathom why they did not make a switch to stainless steel for most of them. Would you recommend something mild such Loctite blue for of the fasteners?
 

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Wingless Wonder
1988 Esprit Turbo
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For an island nation that is known for cold and humid conditions, I can’t fathom why they did not make a switch to stainless steel for most of them.
There are specific parts where using Loctite is beneficial. Most of the time anti-seize helps reduce frustration on fasteners that are periodically loosened.

Fastener corrosion is a common gripe on UK Lotus cars (Morgans, too). :LOL: Don't know whether it was a cost consideration or just 'habit' when the parts were sourced. I know that changing hardware to stainless is a favorite winter pastime for Morgan owners! BTDT
 

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As someone who spends a fair amount of time around boats I can tell you that stainless fasteners used in different metals is not always a good thing. Stainless is "stainless" only if it's exposed to oxygen. The threaded portions of bolts can gall and freeze solid in a number of metals, including aluminum, and especially if exposed to salt and moisture. The bolts may look shiny on the outside but can be a bear when it's time to remove them. Oh, and don't use copper anti-seize either, the copper can actually hasten the degradation. Most marine applications use a product called Tef-gel as it has no metallic content. My suspicion is the manufactures chose steel fasteners as a favor to mechanics over aesthetics.
 

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S/S fasteners are not necessarily "better". As the previous poster says, the environment can be very important. Also depending on the alloy, not all S/S has more tensile strength than steel. Especially Chinese S/S fasteners. I have seen them rust! Ordinary mild steel fasteners, even cheap ones, are plated to prevent corrosion. Of course there is all kinds of plating and the better the fastener the better the plating will be. Even then you must choose the proper plating for the environment the fastener will be subjected to. As a guide you can look at aviation hardware. When using dissimilar metals you must be very careful in your choices. Choose incorrectly and the fastener will fail because of corrosion, not fatigue. Using greases like Never Seize can have it's own bad consequences and then you must allow for the effect it will have on torque when applying a specified torque to effect a certain clamping force. There is a whole science behind the selection of fasteners. Time takes it's toll on plating. It is meant as a sacrificial surface to prevent corrosion but it doesn't last forever. Hardware can be cleaned and replated but again, there is a whole science to that. Do it wrong and you can make it weaker from Hydrogen Embrittalment.
David Teitelbaum
 
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