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Type 9 mounting point
peter_m7uk - 19/3/21 at 09:32 PM

I have my gearbox out at the moment, as I'm going for a rebuild and higher 1st gear. Anyway, it made me think about the rear mounting point, which I know is the lowest point on the car after going over speed bumps!

I kept it as on the Sierra, where a bolt with a long hexagonal end goes through a bell-shaped "washer", then the earth strap is screwed to the end of this hexagon. My question is why the need for this bell-shaped washer? Can't you just leave that off and put an ordinary set screw through the earth strap ring terminal and on into the gearbox? This would significantly raise the lowest point on the car, while still mounting the gearbox and creating an earth...

Pete


rusty nuts - 19/3/21 at 09:45 PM

The big dished washer was installed to a , spread the load on the mounting , b, to stop the bolt pulling through the mount. Fitted a heavy duty mount without the washer on my car


peter_m7uk - 19/3/21 at 09:52 PM

quote:
Originally posted by rusty nuts
The big dished washer was installed to a , spread the load on the mounting , b, to stop the bolt pulling through the mount. Fitted a heavy duty mount without the washer on my car


Hi Rusty. So you're saying the box can bounce up so hard that the edges of the "bell" actually contact the mount?! That's a fair bit of flexing of the rubber. At least the design makes a bit more sense in that case. Where did you get your heavy duty mount?? Might have to consider one.

Cheerz


peter_m7uk - 19/3/21 at 10:20 PM

quote:
Originally posted by peter_m7uk
quote:
Originally posted by rusty nuts
The big dished washer was installed to a , spread the load on the mounting , b, to stop the bolt pulling through the mount. Fitted a heavy duty mount without the washer on my car


Hi Rusty. So you're saying the box can bounce up so hard that the edges of the "bell" actually contact the mount?! That's a fair bit of flexing of the rubber. At least the design makes a bit more sense in that case. Where did you get your heavy duty mount?? Might have to consider one.

Cheerz


I dunno, thinking about it, surely the box would be more likely to break the rubber by falling down through the mount, not pulling up.

Or is it side-to-side movement it's supposed to stop? In which case you could cut down the bell and hexagonal head by about an inch, I'd say. Not entirely convinced that the design isn't overkill.

Has anyone left that big washer off and actually had their mount split, do tell ???


melly-g - 20/3/21 at 12:03 AM

I never put that washer on mine!
14 years it's been on the road now, never had a problem.


obfripper - 20/3/21 at 12:41 AM

I replaced mine with a home made copy of a vibra technics type 9 uprated mount (i looked at the price and thought i can make one of those in an hour). It stopped an annoying judder that occured at certain rpm/loads and is far more effective than the mushy sierra one.

Pics:
https://www.dropbox.com/sh/m9eo8if8hlh1es6/AAAiSemOe5OiMFzkO1VuO_Oya?dl=0


The bell washer is to tether the gearbox if the mount fails (used to happen often with old sierras) or if the vehicle grounds out on the gearbox, before i changed the mount i placed a thick exhaust mounting rubber over the washer before fitting to take up some of the movement, without it the gearbox would knock on the chassis when accelerating and on overrun.

Dave


jps - 20/3/21 at 07:40 AM

quote:
Originally posted by obfripper
I replaced mine with a home made copy of a vibra technics type 9 uprated mount (i looked at the price and thought i can make one of those in an hour). It stopped an annoying judder that occured at certain rpm/loads and is far more effective than the mushy sierra one.

Pics:
https://www.dropbox.com/sh/m9eo8if8hlh1es6/AAAiSemOe5OiMFzkO1VuO_Oya?dl=0


The bell washer is to tether the gearbox if the mount fails (used to happen often with old sierras) or if the vehicle grounds out on the gearbox, before i changed the mount i placed a thick exhaust mounting rubber over the washer before fitting to take up some of the movement, without it the gearbox would knock on the chassis when accelerating and on overrun.

Dave

What bushes did you use for your home-made version? I need to make one at some point, but don’t want it to end up floppier than the original!


obfripper - 20/3/21 at 11:18 AM

They were some drop links bushes from a mk2 astra drop link, but anything of that type should be suitable for the load. IIRC they're 20mm thick, 25mm diameter and a 8mm bore, and the plate is 6 mm thick, folded in the press and welded together.

Dave


peter_m7uk - 23/3/21 at 07:51 PM

quote:
Originally posted by melly-g
I never put that washer on mine!
14 years it's been on the road now, never had a problem.


Very tempted to leave it off, on that evidence!