Motor Mounts -- a couple tips

[Dug Nichols]

I did both motor mounts on my Mintgrun this weekend. As a hack-mechanic (not nearly as inclined as the famed) that prefers to do everything I can on my car, I of course embarked on the mission me-self in the driveway. I researched a bunch about the procedure here in the holy bible of the FAQ, and found some good tidbits, and generally got comfortable with doing the job. Got into it, and of course, met some stumbles on the way which required some patience, thought, and re-go's. 

 

Overall, a pretty straightforward job, but one that is a classic figure-it-out-as-you-go and learn, having not done it before. 

 

Lesson One, Driver Side:

Headline: Way easier to support engine, loosen the nut to subframe first, then jack up the motor (with a 2x4 supporting as much of the oil pan as you can), then tackle the bolt/nut to engine. I figured this out after I'd wrestled with the motor nut on the way out -- access is a PITA.

 

It's easy access from the top and entire job done from there. Made easier for access after I removed the charcoal filter which had long-since been disconnected, but generally in the way. The nut connecting to the subframe was relatively straightforward, using a 17mm open end/box wrench worked well. It's pretty much right there. I struggled for a while figuring out how to get anything on the back nut that attaches the motor mount to the engine -- it was a struggler for a while. I eventually got the same 17mm wrench to work, in really slow movements working the open end a 1/4 turn at a time, back and forth with the wrench (flipping it over) each time. Finally got it loose and went back to jacking up the engine (with a 2x4 spread across as much of the oil pan I could hit), and as I did this I realized that I was an idiot, not having a good mental picture of what to expect, and that, duh, should've just gotten the outside/subframe nut loose and then jacked the engine up to get better advantage on the engine-side nut for the mount. Once I figured this out, putting the new mount in, and then securing it first at the engine, and then lowering the engine back down, and securing both, was a snap.

 

Lesson Two: Passenger Side:

Headline: it's a Hex 6mm in the rear, and it took a significant amount of upward force (jack with 2x4 spread on oil pan) to gain clearance to remove/replace mount. 

 

This side has more parts to it. Nose-end the underneath nut/bolt combo was really easy once I got the engine oil/road gunk cleaned off to see what I'm dealing with (my car is a driver, and with some oil leak issues...). I mainly gut stuck on the rear of the motor mount where there's a 6mm bolt which is accessed through a hole in the subframe member. I had read, here, about this, but in the process maybe failed to internalize... I was trying to work the nut on the top of it, and almost stripped it. Once I figured this out, the rest of the procedure was relatively straightforward and a classic take-it-apart-put-it-back-together process. There's a front and back nut/bolt thing. And a brace that goes over the top, and a nut on the top of the motor mount. The one thing that surprised me was how MUCH force I needed to apply (again, 2x4 on jack spreading across length of oil pan). Finally got the engine up enough to remove the old motor mount, and then putting in the new one realized just how badly my old one was compressed/soft, and I needed jack the engine up even more. It was slightly concerning as the groaning and sounds of the entire car maybe playing with the jack stands started happening. Put the new mount in, and it fit, but needed some encouragement to get all the way into the position where the bolt and holder would seat. Rather than keep straining the oil pan, I grabbed a rubber mallet and gently, oh so gently, tapped. And it fell into place. From there, it was very straight-forward put it back together.

 

Hope this is helpful to any others looking to DIY this job. :)

 

[Rodolfo Lasparri]

Tackling mine soon, thanks for the tips!

[Mike Self]

On the right side mount, make sure that you position the two restraints (that keep the engine in place if the rubber mount fails) so that the engine can't lurch forward enough so the fan takes a bite out of the radiator.  Clearance is pretty close normally, and you don't want to encourage intimacy between fan and radiator.

 

mike

 

PS--and if you have an early car with the one piece, bent metal right side mount, replace it with the later style.  The early ones stress crack and will really mess things up when they break in half.

[TobyB]

Nother thing to check- on the cool side of the engine, the bracket that holds the 

mount to the block often cracks.  It will, eventually, fail.

It's just a folded piece of sheet steel, and the bends were made pretty tight.

 

t

 

[Rodolfo Lasparri]

Thanks Mike and Toby, great intel. I’ll pay extra attention to these points.

[jackm]

I'm getting my mounts loose in prep to hoist engine out. I've got the nut on the driver side out, and with the hoist I should be able to take the weight off the bolt to knock it out. 

 

I'm less clear what to do on the passenger side just to free the engine. Just take the single nut on the bottom off? Or is there something else described here....I guess you are talking about removing and replacing the mount so maybe that doesn't apply to just yanking the motor.

 

Finally, I've heard lots of different things about renovating or improving the motor mounts going forward. I have the circular one on driver side and rectangular one on driver's.

[NickVyse]

change it for the rectangualr one on the drivers side

 

[Pablo M]

Thanks for this extra info. On my list to tackle on my 72 as well. Appreciate it.

[d.hitchcock]

This failure was mentioned above. Figured I'd share my trophy.

[Senna27]

I replaced mine with a rubber one on the driver's side and urethane on the passenger side. The urethane one transferred so much vibration through the car that I replaced it with a rubber one. Lesson learned.