Noticed a drumming/Thumping sound at the bell housing at take off (Like U joint was hitting floor pan). It intensified and came with a noticable loss of power Like The engine was under heavy load. Thumping stopped within a few mins Replaced with a definite vibration of the engine output or tranny shaft It remains the same with the clutch engaged or disengaged - Vibe Dosnt increase with Rpm and seems Intensly noticable when the starter turns the engine -A low slight rubbing sound is noticable when engine is running. No overheating no missing and tranny shifts perfect - Clutch works fine -This happened over the course of a short 12 mile drive , feels very much like a 3 pound weight is slinging around on one side of the Flywheel - Mounts may have some age on them -Manual 4 speed w/ele OD - 1985 240GL Wagon - Any suggestions would be appreciated,
Thanks Much,
Eddog

Eddog,

Glad to hear it was something simple. Tranny mounts will dissolve when too much oil gets on them.

Swapping out the mount(s) is not too difficult.Once you have a replacement mount(s)..... I set my Volvo on jack stands at the front only. Make sure the car and stands are secure. I'm a wimp when it comes to crawling under...I'll push and shove the car in all directions to make sure I can't get it off the stands when I'm under there pushing and pulling. At any rate.......once the car is secure: take a jack, place a small bit of 2X4 between the jack and where the jack meets the engine and tranny (seam of bell housing and engine), snug the jack, but dont raise the engine and tranny yet.
The bolt securing the tranny mount is on an angle and accessed through the cross frame (through the hole) the attachement at the tranny is a bear to get at, take your time and it will come off. Once the nuts are off, slowly raise the engine and tranny till you can remove the mount. As the manuals say "refitting is the reversal..." !!

If you are doing the motor mounts as well (before or after tranny mount). I place the jack (2X4) on the oil pan drain plug and raise the engine from there. Again, just snug till all nuts are off...raise and replace. When you raise the engine you may want to wedge bits of 2X4's on the sides of the engine to keep it from turning one way or the other.....or sling it if you have a engine puller or have rigged one.

Hope this is helpful. Again let us all know how you did.

Al

Well Its the Mounts, Tranny Mount is metal to metal - Bought new mounts and dove into the the job this morning but Mr Murphy threw a curve - I loosened the bolts in the motor mounts and removed both nuts on the tranny mount - Jacked the tranny with a wood block as far as it would go, problem Im having is the Mount bracket on the Tranny housing is near touching the frame bracket and I can't get clearance to remove the old mount- It looks like the motor and tranny have to move forward about 4 inches. I ran out of time and shoved a 1.5 inch chunk of heavy rubber into the area of the mount lowered and bolted it up again - Noise is all gone but I still have to do the job. Do I have to completly un-bolt the Motor mounts and scoot the engine fwd to get the clearance to remove the Tr mount Is there an easier way? Ive got an engine hoist but Im worried about bending something or cracking the Aluminum intake B-23 motor. What am I doing wrong or am I just not wrestling it enough ? Wow Noticed my floor pans are about shot (rust) I gotta stop looking for things to fix - Thanks much & Good New Year All,
Ed

If I'm reading this right......you get in, fire it up....you hear thumping and clunking noise from the bell housing.....before the engine actually fires.

I'd check the motor mounts. With engine off, e-brake set (or in gear if your e-brake is like mine) open hood, check distance from valver cover to firewall. If it is really close to firewall, your tranny mount may be the culpert or one/ both of your engine mounts. While your in there, grab hold of the engine (by the valve cover) and rock it back and forth (side to side) as hard as you can. You may hear your sound (reduced) as either your exhaust system, bellhousing, tranny , engine bumps against the chassis.

I'd suspect tranny mount. Any of the mounts can be replaced with out removing the engine or tranny. If it is a bad mount....do them all while your at it.

Let us know what you found.

Al

84, 242 GLTi, 4+OD, 116K; 89, 245 DL, 5 spd, 238K plus other toys.

Bingo!, Thanks AL:
The edge of the valve cover is 1 inch from the fire wall. Looked at the Motor mounts and the engine is setting off center & to the rear of the mounts - Gave the valve cover a good solid shake and I can get it to move a little . Started the engine and gave a good listen - It sounds like the tranny is pressed tightly against the side of the floor pan and the sound is regular engine/drive drain noise transmitted right into the passenger compartment (no more thumping)- Looked at the tranny mount area and seems like there is not much left there. I think the mount must have slipped or dissolved and when it first started I heard the Ujoint slappin the floor pan a few times. The tranny must have moved and made contact with the Floor pan. Its a scarey sound - I was getting ready to to replace the clutch/ U joints& bushings,This will be a much easier fix - Ill look thru the archives for the procedure,
Thanks again,
Ed

It could be the rubber driveshaft center bearing support bushing or the u-joints. Check the motor and trans mounts and the driveshaft. Good luck. Dan
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85 245 M46 188K, 92 245 A70 115K

The U joints and drive shaft was my first thought but The problems happen when the driveshaft is disengaged and not turning -Out of gear, or with the clutch pressed to the floor- It makes an intense warbling vibration when the Tranny is in neutral Car not moving and you crank the engine to start it up - The Vibe can be felt with the motor spinning before it fires . It dosnt seem like it could be anything after the transmission ? Could it ?