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Just go with Centerline or any other recommendations?


Will be getting this replaced in the next few months.

Thanks
 

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I just installed one from Classic Alfa based in the UK. It seems a bit on the large size making it very hard to get in place and risking breaking the housing on the trans that holds it even using the freeze the bushing, heat the trans mount method. Don't know if the Centerline version is any different, good or bad, just my current experience would say to try the one from centerline. I understand all the after market ones don't have the precision of the originals as far as fit.

Good luck!

Jim
 

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whatever one you buy, use a good micrometer (accuracy to <= 0.001 inch) and measure the old one, and make sure the new one matches. Also check its ovality (measure diameter in a few places on the circumference). If its too large -- at all -- turn it down on a lathe.
 

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My Centerline mount was too big.

If there were a source that had a mount guaranteed to fit, it would be worth a premium.
 

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3 mounts I have in stock, 1 and 2 were mounted in a trans no problem, 3 is NOS. Range is 63.98 -64.02mm

measurements on the paper are two diameters, 90 degrees offset, both sides of mount

0.01mm is close to 0.0004 inches so range here is about 1.5 thou. I’d say if larger than 64.03 it might need some skimming

“ring stress” - mech eng term that is used to define the stresses placed on both the mount and the housing - when it’s an interference fit - is a tough stress to manage. No real deformation is possible as the material really has no where to go. That’s why any of these kinds of fits have to be dimensioned correctly.
 

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As stated, measuring is the most important thing. I have installed mounts from Centerline and Classic Alfa with no issues
 

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3 mounts I have in stock, 1 and 2 were mounted in a trans no problem, 3 is NOS. Range is 63.98 -64.02mm

measurements on the paper are two diameters, 90 degrees offset, both sides of mount

0.01mm is close to 0.0004 inches so range here is about 1.5 thou. I’d say if larger than 64.03 it might need some skimming

“ring stress” - mech eng term that is used to define the stresses placed on both the mount and the housing - when it’s an interference fit - is a tough stress to manage. No real deformation is possible as the material really has no where to go. That’s why any of these kinds of fits have to be dimensioned correctly.
Those are pretty good as far as roundness goes (ovality). I agree the max is likely a bit over 64, at this diameter. I like to use a small cylinder hone, and clean out the ID of the transmission hole also, before installation. Then a film of Lubriplate.
 

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Good thread, lgb, thanks for askinlg the question. I would have ordered whichever one, pounded on it, and not understood what I had done wrong.

Is this a joint that should be lubed to install, or should it be dry?
 

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Good thread, lgb, thanks for askinlg the question. I would have ordered whichever one, pounded on it, and not understood what I had done wrong.

Is this a joint that should be lubed to install, or should it be dry?
I never lube but i do measure
 

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Pressed in uniformly. I use a big steel washers and long bolt, with nut, to draw it into the hole. I've also used a big c clamp.
 
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One other thing - on some of these new mounts, the outer surface is pretty rough - I’d think hitting it with some 600 grit paper to smooth the surface out would be a wise move.
 

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One other thing - on some of these new mounts, the outer surface is pretty rough - I’d think hitting it with some 600 grit paper to smooth the surface out would be a wise move.
Correct-- they are NOT a precision OD ground item. And they need to be.
 

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it's almost a alfa romeo spider
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advice... fill in the voids.. will make it stronger, and with little if any more vibration.. and before you install them freeze them 24 hours as cold as you can get them... even cheap dry ice in a cheap cooler is better.. and it will slip in easier
 

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advice... fill in the voids
Good one. Before you install the mount, tape off one end and fill the voids with 3M 08609 window weld polyurethane.

I am working on a Delrin mount, but the rest of my drivetrain will also be on Delrin. Not sure you want any motor movement if you have a solid mount on the trans.
 

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Good one. Before you install the mount, tape off one end and fill the voids with 3M 08609 window weld polyurethane.

I am working on a Delrin mount, but the rest of my drivetrain will also be on Delrin. Not sure you want any motor movement if you have a solid mount on the trans.
Delrin?
Are you planning to race this car? I ask because I fear that you will get a lot of vibration transmitted to the body if you go that route.
 
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Greg's right guys-- there are testimonies here on the BB about filling in those spaces with poly or other harder material. You will get more vibration, according to others' experiences. If it's a track car, then I suppose that's no issue.
 
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i have installed a polly insert on a few car.. no added vibration...some people feel what they want to feel.. as a tech after we work/ repair a car.. some customer come back and complane about something we did not work on.. you fix one problem,, that perhaps was overshadowing a diff problem that was there in the first place... we /I fixed some front brakes on a customers car due to vibrations ( they were close to worn out ) fixed the brakes i bedded them in correctly.. customer took the car home, only to show up a few days later.. saying is still has a vibration.. the dampners were oem 9 years old..... have any of you fix a part of your car, only to find out there was different problem, hiding in the car?
 
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