Replacing Motor Mounts and Spring Mounts?

[40ZephSedan]

How do I replace motor mounts and spring mounts? My 40 sedan has a loud metal engine vibration, and I have ridden in many quiet V12's! Checked the exhaust, fixed it where was rubbing in the frame where goes thru 2 holes up front, but not much quieter. Have 2 new motor mounts. May need the 2 front and 2 rear spring mounts too, and a tranny mount by the looks of the rubber ooozing out, to get rid of all metal vibration noise. Don't think my dad replaced them in 1972 by the looks- I was too young to remember. Looks like I can remove radiator hoses and raise engine enough to get the motor mounts out. Got the 1 bolt (5/8 socket) out of engine top side. Second small bolt from the bottom looks impossible to get to, & large main bolt (15/16 socket?) on bottom I can see the nut- sandwiched under the cross member frame/above the leaf spring. But no room to get a socket on at an angle. Anyone ever replace motor mounts without pulling engine? And have not started spring mounts yet. Can I jack up the body high enough off the axles/springs, to slide 4 old mounts out and slip new ones in? (still need to buy these spring mounts!) Thx a bunch! Paul

[Mssr. Bwatoe]

Hi Paul, I would remove a 4 hoses, one blind bolt threads into block, the other has a nut...but, loosen the large castle nnut under car first, lube em up as last I did the blind bolt spun inside the mount,and I ground it off with cutoff wheel...

engine can be jacked from under, a board and floor jack. On the oil pan..rear mount is a hoop that requires moving trans or rear axle. Yikes! Prime time for new hoses, water pumps...clutch...maybe pull radiator...how much of a project to get into is question...look at ft mounts closely,are they sagged, the metal attatched to engine is seated in rubber, if they have worked through the cushion, they could be sitting on metal. I would lift engine some...look and see if the are no llonger holding...you I could lift and slip a hard rubber insert in between as temp. T help diagnose problem...

[John Murphy]

Paul, do you mean "Frame Insulators" in place of "spring mounts? Back springs should be no problem. Couldn't find any article from TWOZ back issues on the subject. Suggest a call to Earle or Warren Rice in Michigan who originally reproduced the motor mounts and frame insulators. Don't envy the solution...u gotta lotta of work ahead of you. Don't forget your hard hat...

[40ZephSedan]

Appreciate the help guys! Working on the motor mounts first. Wire brushed the threads- lubed w/ PB Blaster. The bottom 1 of 2 large castle nuts came off easy. After I jacked body up off axle and stretched the leaf spring I was able to slide a 1/2" socket extension with swivel up vertically in between the axle and spring at slight angle for 15/16" socket. But 2nd bottom castle nut/stud are spinning. The stud should probably be welded in because you can't put a wrench into the rubber to hold any bolt head, but somehow stud is spinning and nut won't spin off. Tried to chisel nut off but countersunk in a recess and chisel too wide- hits the cross-member instead of nut. Getting a long aircraft drill and will try to drill up the slot in castle nut to split the nut and get it off. If that does not work I will find a long narrow chisel, or grind one of my long fat chisels so it is narrow enough to split nut only inside countersink. Has to be long narrow chisel to not hit the cross-member. No room to fit my die grinder up there, and Dremel would take 3 years! Got 2 top small bolts out easy- was able to slip wrench in from top/side to hold nut. Have not tried the two small blind bolts yet, but think can get those out with small 3/8 drive socket from side.

PS: Will not do 4 rubber coated spring-frame mounts till after motor mounts done. Looked in Parts Manual (but not in diaphragm) they are called Insulators (frame-cross member) part #96H-5044 for my car. Rear one should not be as bad, Jeff already showed us how fast he pulled the back end apart, with great photos, for his Columbia 2-speed. Talked with Al from the club, said just have to jack body up real high off axles to get frame insulators out, but must remove brake lines, shock links, stabilator links, hoses, etc because the body needs to raise so high. I see my front stabilator bushings are pretty lose/egg shaped too, another future project! Happy Labor Day! Paul

[40ZephSedan]

Motor mounts done-good feeling! Were totally collapsed- touching metal to metal on bottom. Photo shows new mount much taller on left, with rubber between the metal! Would have been much easier if 1 large castle nut didn't spin. Stud had a round head under the rubber- that broke lose. Had to drill vertical 3/16" holes up the castle nut slots in a few places to split old nut off, using a long aircraft drill bit from Sears Hardware. So was able to replace both mounts on my back underneath with wheels blocked up, the body jacked part way up off axles/springs, and then with board under pan- jacked the engine up off cross-member. Only removed 4 radiator hoses & vacuum line to intake to raise engine. Like Jeff said, after jacked the engine up, could get the 2 small inner blind end bolts out with a 3/8" socket swivel drive on the 5/8" bolt heads. Going back in, u can not bolt up mount bolts tight & drop in hole, because stud is off at an angle so too wide to drop into stud holes. Need to have only the 2 small inner (blind bolts) installed so the large stub can swing down vertical. until studs drop into holes, then can put the small outer bolts/nuts in - which pulls the mounts up and studs swing off at an angle after already inside the cross-member hole. Can't wait till new hoses come in so I can see how much quieter the body hum/vibrations is. But still need tranny mount and 4 frame insulators.

[Mssr. Bwatoe]

Good show Paul, those mounts were wasted, These are not quiet cars, but this will make 100% improvement.. The trans mount can wait, drive and see..

[40ZephSedan]

Body/Frame noise and vibration much improved! More muffled engine noise that sounds like coming from under hood now, rather than before it was loud and sounded like it was coming up right under the seat and floor. Smoother roar when rev up a little shifting thru the gears, sounds nice. And Earle's new hoses look nice too! Fun to get another item off the list so more enjoyable to drive!! Can't wait to do 4 frame insulators above springs and tranny mount - that rubber really looks 73 yrs old, can only get better! Paul

[DSpringer]

Paul, may I ask where you got the replacement mounts? Not sure, but I may be needing some soon for the V12 I'm picking up Friday. Yay!

[40ZephSedan]

I picked up my motor mounts from a friend on the east side of Cleveland yrs ago. He had a Mark 1 and restored a beautiful 40 Cabr., high points getter. He was offered a price he could not refuse and sold it to a buyer of a private family museum. So ended up selling off all his spares separately. Sold me many parts at a very reasonable price, and at the end actually gave me many as well. So I never did any research on availability and pricing for motor mounts. Good luck.