Author Topic: Engine sags when body is jacked up... Fintail sedan  (Read 4489 times)

scoot

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Engine sags when body is jacked up... Fintail sedan
« on: April 06, 2014, 14:54:58 »
I realize that this isn't a Pagoda question, but I strongly suspect that the answer is the same.

I have a 1963 220 Sb W111 sedan.  If I support the car by the front jack points, the engine and front suspension and front axle settle downwards to the point where the engine can touch the steering cross piece.   I know this is not right.  At first I thought it was old/bad motor mounts, but the more I think about it, the more I think that something else should be supporting this and I'm wondering if the subframe mounts hold the frame to the body...  Perhaps mine are either rotten or disconnected?

Thoughts appreciated.
thanks
Scott
Scott Allen
'67 250 SL (early)
Altadena, California

stickandrudderman

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Re: Engine sags when body is jacked up... Fintail sedan
« Reply #1 on: April 06, 2014, 16:24:57 »
Indeed it is likely that your front sub frame mounts are perished, and probably your engine mounts too.
I'm an advocate of changing ALL rubber on the car at the same time as this way you get the full benefit (and an astonishing improvement in ride quality) of new parts. New parts mixed with old is always a compromise.
Here's the safety case:
If you are driving your car in spirited fashion and crest a hill or hump, the car will become partially (or even fully) elevated and allow the sub frame to sag as you have described. This in turn presents the very real danger that the steering drag link fouls the sump. Not a good thing!

Desertpagoda

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Re: Engine sags when body is jacked up... Fintail sedan
« Reply #2 on: April 10, 2014, 19:17:23 »
And once you've replaced the subframe mounts with new, don't allow the front subframe to hang by them. They will be pulled in two pronto! The entire weight of the engine/drivetrain/subframe will be hanging from them! Keith
kb

scoot

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Re: Engine sags when body is jacked up... Fintail sedan
« Reply #3 on: April 10, 2014, 19:20:57 »
And once you've replaced the subframe mounts with new, don't allow the front subframe to hang by them. They will be pulled in two pronto! The entire weight of the engine/drivetrain/subframe will be hanging from them! Keith
Yeah, I remember now, and I'm pretty sure I caused the damage by having the front end supported by the jack points for 2 weeks while I was trying to sort out the front brakes...  At least they were ancient before I broke them...  I remember replacing them in a 108 that didn't have an engine in the engine bay and it was super easy.  I'm hoping it isn't too difficult with an engine sitting there...
Scott Allen
'67 250 SL (early)
Altadena, California

mbzse

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Re: Engine sags when body is jacked up... Fintail sedan
« Reply #4 on: April 10, 2014, 19:50:03 »
Quote from: scoot
.../...replacing them in a 108 that didn't have an engine in the engine bay and it was super easy.  I'm hoping it isn't too difficult with an engine sitting there...
You can find a pretty good description of this subframe exchange task here: http://www.peachparts.com/Wikka/W108Subframe
/Hans in Sweden

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/Hans S