motor mounts failing

Hi, you need to get a long lever bar in there and see how much movement there is in each mount - mine were a bit soft and moved about 4 - 5 mm so I replaced them all - not very hard to do but they're not cheap!!

 

FWIW, the classic check for bad mounts on a typical US car is to open the hood so you can see the engine, have a helper get in the car, start it, apply the brakes FIRMLY, put the transmission in reverse, and slowly apply power while easing out the clutch. It requires some heel/towing on a manual - foot on brake while applying some throttle. Do the same in 1st. If the mounts are bad, one side of the engine will clearly lift beyond the normal "flexing." Apply FIRM braking so car does not actually move.

 

As I read the responses thus far, they imply that the height of the engine (that is, the vertical distance taken up by the mounts) is not a tell-tale for bad mounts. So, does that mean the mounts can appear totally normal but be worn out inside? That would make sense if there is a damper inside the mounts in addition to a spring, and just the damper is shot. But wouldn't worn or broken springs inside the mounts be another tell-tale, evidenced by a collapsed mount (and easily measurable)? I imagine there are reference measures for proper engine height front and rear above the cross members. Is this available?

 

" So, does that mean the mounts can appear totally normal but be worn out inside?" Absolutely - there could even be "nothing" inside!

Also - and I have never looked at the main Ferrari motor mounts so I don't know how they are made - but many engine mounts consist of 'rubber' sandwiched between two metal plates. When the mount fails, it is because one of the plates separated from the rubber so the mount looks perfectly OK when the car is parked/idling but when any load is applied to the engine, it rotates up/off the bad mount with either reverse or forward load.

 

They come with various shim stacks from the Factory, someone losing them over time would result in a droop.

It is in fact a sign (as I mentioned somewhere else recently) that if your headers at RH side are hitting or near to hitting the frame, they may have sacked out.
There's normally a half inch or so clearance at that point.

Our 308 mounts are little complicated rubber/spring isolators.

There's a thread where a guy drill some Summit Racing Mustang mounts, but that makes the mounting solid!
Rifledriver said: "you won't like the vibration" so I guess that's why ours are the way it is!

 

Hand built cars. Do you have any other reason to think mounts are bad? I've seen ebrake cable hit header and I recall shimming to correct. This was 25ish ++ years ago and haven't given it another thought. Well- 'til now

BTW: There are lots of common areas of maintenance on these gorgeous machines, and I don't recall 308 mounts being an issue? I've changed a Boxer mount 'cuz plating was getting sad looking and rubber had a cut in it, but the 308 mounts seem to be quite robust.

 

If you can feel the engine vibration in the car, more likely the engine mount is or are bad.

 

The parts manual shows a spacer on the front mounts 107424. The front mounts should also have a red dot and they have a different part number 106034 from the rears 106035. I don’t know what makes them different and replacements that I have seen for sale seem to be just one part number. Here is a picture of the two including the spacer.

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Parts book also shows 4 shims 106029 that look like this:

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The top bell on the fronts looks visibly shorter, to my eye???

 

No it is just the perspective of the camera. Both measure at 77mm.


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Do you have some pictures of the exhaust system from the rear? Interested to see if you still have the factory hangers and what the muffler looks like.


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Just replace them all PERIOD , you will be absolutely happy , FERR parts in California has them at a fair price, I did mine, and I could feel the difference right off the bat, your car will shift like a hot knife through butter , and the handling will improve as well.

Thank you

 

Wow, I could have welded that, and I can't weld...
/Peter

 

Nothing much inside these other than a spring a rubber bush and some wire wool Image Unavailable, Please Login

 

What the hell...?

 

Solid mounted exhaust to frame genius