98 V70 engine mounts

[98v70dad]

I've already replaced a bunch of the engine mounts (Volvo parts from dealer) in my car about a year ago - most of the easy ones. I still have the transmission link to do (easy), the firewall end of the top link and the front and rear hydraulic mounts. I haven't inspected the ones below but at least one or some or all of them are bad. The firewall side of the top link looks OK. Sub-frame bushings are also original - radial cracks every half inch (all around) where I can see.

New control arms solved my wheel vibration problem (like riding on rails now) and I'm now left with a much less annoying buzzy (feels like a buzz not so much a sound) sort of vibration upon acceleration. I suspect that its source is engine mount related. When I'm accelerating I get the buzz from the front and when I take my foot off the gas it stops. I can make it worse by playing with the speed, acceleration and gas pedal.

Anyhow, I've started looking at what can be replaced for low cost and easily. I'm most inclined to buy the highest quality parts I can stomach since usually I'm investing a Saturday to put them in - my labor is free in money but very costly in using my limited free time.

Any recommendations on what is the highest probability mount to be causing my problem and recommended parts would be appreciated. If OE is the only way to go - so be it, but just knowing who made the parts for Volvo originally helps a lot. Usually those are a good value with a long service life.

[misha]

Did you checked engine mount near crank pulley?

[98v70dad]

Thanks, yes. As I said, I've replaced several of them within the last year to 18 months except the few I mentioned. The mount near the crank pulley that you asked about was replaced with a blue box Volvo part from the dealership. The old part was completely flat.

[bmdubya1198]

Funny you mention that. When I brake, right as the car comes to a stop, I get a nasty vibration. After checking out the mount under the crank pulley (complete coincidence I noticed it while checking out my water pump), it looks crushed. I'm hoping that's the issue, and judging by how squashed it looks, it's definitely bad.

[sleddriver]

OP: I'm willing to bet that the drvr side end-of-the-trans. is sitting on the sub-frame bump stop. This leads to a direct conduit for engine buzz & vibration into the cockpit. This occurs when the rear HMM collapses. You can pull the drvr tire and have a look.

Replacing both HMM's will be much less of a PITA for you because your sled is NA, thus no turbo heat-shield covering the rear HMM, nor constricted access to the upper nut holding the mount in place. Further, study carefully the IPD .pdf on installing their front HD sway bar, as truly "dropping" the sub-frame will make this job MUCH easier. (See my earlier post on this). Further, those two rear SFB's will be much easier to access should you choose to also replace them.

Both the engine & tran's mass is supported by the two HMM's and the mount below the crank pulley, forming a tripod. When the HMM's collapse, the trans. sits down on the drvr side SF. The upper/lower torque mounts are just that: Torque. Not mass. If you remove both, the engine doesn't fall down. It will and does sag over time with the three above. This is why the engine/trans has to be jacked back up when replacing them.

The front HMM is quite straightforward. As a start to both, try to bust the upper nuts loose first. Mine both made a CRACKING sound when they finally busted loose! I soaked both threads with 50/50 acetone/ATF. I spent a few hrs just on them due to access angles, turbo interference, etc. Break the job down into manageable chunks. Save time & frustration on the rear by using a Sawzall to cut the upper mounting stud off. It'll make removing it MUCH easier.

Re: HMMs. One is Corteco, the other Hutchinson. Both OEM suppliers. I ordered them from RM-Euro due to my location.

[Jaguar xjs]

I'm very new to Volvo but have been wrenching on cars for 40 years. I recently replaced all the mounts in about 6 hours.

I removed the upper and lower torque mounts and mount under crank to give me more lifting height to allow removal of the HMMs. The old mounts were very collapsed and did not require going very high for removal. However, the new mounts, all blue box were substantially taller out of the box. I had to jack the engine and transmission quite high and needed the use of two floor jacks to gain enough room for the installation of the the HMMs. There is a nice video from FCP on the changeout but he does make it look a bit easier than it is.

It was well worth the effort and expense. The car rides quite smooth and the transmission shifts a bit softer not to mention the engine is not rocking about on gear changes, acceleration or deceleration.

[98v70dad]

OP: I'm willing to bet that the drvr side end-of-the-trans. is sitting on the sub-frame bump stop. This leads to a direct conduit for engine buzz & vibration into the cockpit. This occurs when the rear HMM collapses. You can pull the drvr tire and have a look.

Replacing both HMM's will be much less of a PITA for you because your sled is NA, thus no turbo heat-shield covering the rear HMM, nor constricted access to the upper nut holding the mount in place. Further, study carefully the IPD .pdf on installing their front HD sway bar, as truly "dropping" the sub-frame will make this job MUCH easier. (See my earlier post on this). Further, those two rear SFB's will be much easier to access should you choose to also replace them.

Both the engine & tran's mass is supported by the two HMM's and the mount below the crank pulley, forming a tripod. When the HMM's collapse, the trans. sits down on the drvr side SF. The upper/lower torque mounts are just that: Torque. Not mass. If you remove both, the engine doesn't fall down. It will and does sag over time with the three above. This is why the engine/trans has to be jacked back up when replacing them.

The front HMM is quite straightforward. As a start to both, try to bust the upper nuts loose first. Mine both made a CRACKING sound when they finally busted loose! I soaked both threads with 50/50 acetone/ATF. I spent a few hrs just on them due to access angles, turbo interference, etc. Break the job down into manageable chunks. Save time & frustration on the rear by using a Sawzall to cut the upper mounting stud off. It'll make removing it MUCH easier.

Re: HMMs. One is Corteco, the other Hutchinson. Both OEM suppliers. I ordered them from RM-Euro due to my location.

Thanks for the info. When I buy the parts corteco/hutchinson is what I'll buy!

When I thought I had the jiggling problem whipped I got inspired and figured that I'd change out the sub-frame bushings and a couple more engine mounts and be home free. I test drove it extensively after replacing the control arms and it drove about 50 miles without a wobble or jiggle. Same result driving to work this morning - smooth as glass and temperature was about 60 degrees. Then it got hot today. 90 F in the engine compartment driving home and the jiggle wobble started up again. Its much much better but still there. It seems to be temperature dependent which I can't explain. I need to take a day off from my super needy volvo and think it through. Not really sure what to do next - maybe check the front wheel bearings.

[sleddriver]

.....I had to jack the engine and transmission quite high and needed the use of two floor jacks to gain enough room for the installation of the the HMMs. There is a nice video from FCP on the changeout but he does make it look a bit easier than it is. It was well worth the effort and expense. The car rides quite smooth and the transmission shifts a bit softer not to mention the engine is not rocking about on gear changes, acceleration or deceleration.

It is indeed rather amazing when jacking to realize just how far down the engine/trans. has sunk! AND how much HIGHER the motor sits on the new mounts! AND how much better, smoother, and quieter the ride is afterwards!!

As for Ben's video.....not a turbo car I recall and he does indeed make it LOOK easy. However, I wonder what all is edited out? Besides the cussing!

[bmdubya1198]

Ben's video is on an 850 Turbo. He makes it look easy for the video, but there are obviously lots of parts that weren't shown... probably filled with nice names for the car.