We have installed the rebuilt engine together with new Volvo motor mounts today.
(The cat and and muffler not yet installed) The engine started Ok but it it is vibrating a lot at idle. You can move the engine side to side with both of your hands. İs this normal, do they settle in time. Are the Volvo mounts much softer compared to Porsche original motor mounts?
Thanks,

 

Double check all of your motor mount bolts and mount brackets. This does not sound normal. Mine hardly moves at idle. It should only move when you rev it, and it's smooth from side to side (rocking).

Also check mount position and the safety hooks. You can jack the engine up by the oil pan, little steps until the hook is bent.

 

I have the new ones as well, put in after an engine pull for a top end rebuild last summer. We noticed they ran a little higher than stock of course since the old ones were pancakes after 30 years but nothing abnormal the way you describe,,, I think they made an immediate difference in my case. Noticed no unusual vibration.

What model and year?

 

Volvo mounts on my gts, engine is really standing still at idle, then rocks when I push accelerator. Something is not OK...

 

Hmm- That's exactly how they're supposed to behave. Nice and smooth at idle, enough elasticity to flex with the torque of the motor when you accelerate.

 

What Rob said.

 

Which Volvo MM did you use - lots of different MM's?

 

Roger Hi,

I will definitely check that, what is the correct Volvo part number that we should be using.

Thanks,

Evren

 

Following what others have shared so far--

Connect the rest of the exhaust and plumbing, so the engine has a chance to idle smoothly.

What year is your car, and is it US or ROW/Euro? Rough idle can be so many things, it will be easier to narrow down the possibilities if we know what car you have.

The purpose of the mounts is to support the weight of the engine, while isolating the car from minor engine vibrations. There is a small amount of lateral movement available, but the safety hooks around the mounts really limit how far it can move. Similarly, the hooks limit upward travel of the engine to a very small amount when new Volvo mounts are used. The hooks often need to be adjusted open slightly so they aren't solidly engaged with the new slightly taller mounts. Did you reinstall the safety hooks that constrain the new mounts?

 

Presumably, this is not pertaining to the blue cars?