NJFBOA - Home of New Jersey's Camaros and Firebirds

NJFBOA - Home of New Jersey's Camaros and Firebirds (http://www.njfboa.org/forums/index.php)
-   General Tech (http://www.njfboa.org/forums/forumdisplay.php?f=37)
-   -   Saab issue (http://www.njfboa.org/forums/showthread.php?t=47381)

qwikz28 10-11-2009 05:14 PM

Saab issue
 
My father found a fabulous European car mechanic that he takes his Saab to. The guy replaced a motor (or may have been trans, not sure) mount on the car not too long ago but now is saying the motor is out of alignment. I have never heard of such an issue, did my dad misunderstand him or is this possible? Car is a 2003 Saab 9-3 Vert with ~95k on teh clock and the 2.0 turbo motor and an automatic. Car is FWD and drives well as far as my dad can tell, this was brought up when my father proposed replacing the shocks on the car.

sweetbmxrider 10-11-2009 07:12 PM

doesn't look like it but i know vw's have mounts that need to be in a certain position.

Background
The balancer shafts are most effective within the normal working range of the engine, from 1800 rpm and above. From idling speed up to 1800 rpm , the balancer shafts are unable to counteract engine vibration.
To effectively dampen engine vibrations at lower engine speeds, the rear and right-hand front engine mountings are hydraulic. They are most effective between idling speed and approx. 1800 rpm.
The advantages of hydraulic engine mountings:

* improved damping of horizontal engine movements during acceleration
* improved damping of vertical engine movements on bumpy roads
* improved damping of engine vibration at idling speed
* reduction of structure-borne noise between engine and body.

Description
The hydraulic mounting consists of two chambers filled with a special damping fluid. There is a diaphragm and a passage between the two chambers where the length and cross-sectional area of the passage determines the damping characteristics of the mounting. The diaphragm absorbs the forces generated by the normal small movements of the engine.
The affect of the diaphragm is not sufficient to dampen more pronounced engine movement. Fluid is forced from the upper chamber to the lower chamber, equalizing the pressure. This gives the hydraulic mounting a progressive damping action, resulting in increased resistance with increased load.

hope that helps

TaKid455 10-11-2009 07:17 PM

If the motor is misaligned with the trans, then you will have some issues. you would see a gap between the trans and motor if this were the situation. I am not aware of this engine having a balance shaft. that would cause a vibration if it was out of sync. this would not be touched if the trans was replaced though. Only if teh timing belt was changed.

the trans and engine can be shifted within the mounts, but about 1/2" max movement which would not affect much. I would ask for clarification on the diagnosis.

qwikz28 10-11-2009 09:31 PM

Quote:

Originally Posted by sweetbmxrider (Post 643739)
doesn't look like it but i know vw's have mounts that need to be in a certain position.

Background
The balancer shafts are most effective within the normal working range of the engine, from 1800 rpm and above. From idling speed up to 1800 rpm , the balancer shafts are unable to counteract engine vibration.
To effectively dampen engine vibrations at lower engine speeds, the rear and right-hand front engine mountings are hydraulic. They are most effective between idling speed and approx. 1800 rpm.
The advantages of hydraulic engine mountings:

* improved damping of horizontal engine movements during acceleration
* improved damping of vertical engine movements on bumpy roads
* improved damping of engine vibration at idling speed
* reduction of structure-borne noise between engine and body.

Description
The hydraulic mounting consists of two chambers filled with a special damping fluid. There is a diaphragm and a passage between the two chambers where the length and cross-sectional area of the passage determines the damping characteristics of the mounting. The diaphragm absorbs the forces generated by the normal small movements of the engine.
The affect of the diaphragm is not sufficient to dampen more pronounced engine movement. Fluid is forced from the upper chamber to the lower chamber, equalizing the pressure. This gives the hydraulic mounting a progressive damping action, resulting in increased resistance with increased load.

hope that helps

I doubt the Saab has any of that fancy stuff. Still interesting though


Quote:

Originally Posted by TaKid455 (Post 643741)
If the motor is misaligned with the trans, then you will have some issues. you would see a gap between the trans and motor if this were the situation. I am not aware of this engine having a balance shaft. that would cause a vibration if it was out of sync. this would not be touched if the trans was replaced though. Only if teh timing belt was changed.

the trans and engine can be shifted within the mounts, but about 1/2" max movement which would not affect much. I would ask for clarification on the diagnosis.

there aren't any vibrations, and the trans and timing belt were never serviced. And for what its worth, the car was in only a minor rear end collision that only pushed in the bumper, kinked the quarter panel, and dented the trunk lid; very minor. I guess clarification is needed.

Thanks for the help guys

sweetbmxrider 10-12-2009 07:21 AM

Quote:

Originally Posted by qwikz28 (Post 643768)
I doubt the Saab has any of that fancy stuff. Still interesting though

sorry, that is for the saab you specified according to alldata. i just mentioned the vw thing fwiw

qwikz28 10-12-2009 12:06 PM

Quote:

Originally Posted by sweetbmxrider (Post 643842)
sorry, that is for the saab you specified according to alldata. i just mentioned the vw thing fwiw

interesting, that explains the $500 estimate to replace the motor mount. if it is a hydraulic mount, it is possible then, thanks!


All times are GMT -5. The time now is 12:03 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.