Motor mount

[adileo]

Hi guys

Am I correct? Motor mount castle nuts don't have to be very tight. As long as you can get the cotter pin through and nut is snug - good enough?

Thanks

Andy

[Drbrown]

Correct. Recently replaced my '47 front engine mount pads and had to tighten the castle nuts down quite a bit just to get the cotter pins in.

My old pads were very spongy and the old bolts were just hanging loose. The new pads raised the front of the engine about 3/8 of an inch. Had some initial vibration after replacement but that went away after driving the car awhile and the pads settled-in. Because the engine sits a bit higher, had to make minor adjustments in the choke and throttle cables where they pass thru the fire wall so they work okay with the carb. Other items like shift linkage and exhaust piping have not seem affected.

[40cpe]

I just put 4 new mounts on mine. The bottom insulators are thicker than the ones that came off. I had to struggle to get the nuts started on the bolts. After I tightened them enough for a cotter pin the vibration felt like the engine was bolted directly to the frame. I loosened them to where there is about 1/2 of the nut on the bolt and it is normal now. I plan to take them out and trim some of the lower insulator off.

[40cpe]

Originally Posted by adileo

Hi guys

Am I correct? Motor mount castle nuts don't have to be very tight. As long as you can get the cotter pin through and nut is snug - good enough?

Thanks

Andy

Andy, did you use Drake mounts?

[adileo]

Originally Posted by 40cpe

Andy, did you use Drake mounts?

Thanks guys!

I don't know what mounts I have. I recently replaced my water pumps. The mounts looked perfect so I did not buy new ones.

Andy

[V8COOPMAN]

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Originally Posted by 40cpe

I just put 4 new mounts on mine. The bottom insulators are thicker than the ones that came off. I had to struggle to get the nuts started on the bolts. After I tightened them enough for a cotter pin the vibration felt like the engine was bolted directly to the frame. I loosened them to where there is about 1/2 of the nut on the bolt and it is normal now. I plan to take them out and trim some of the lower insulator off.

Why not replace the bolts with something of the proper length? DD

[40cpe]

I compared the new bolts to some originals, they are the same length. They have the big body, big hex head, etc. It appears that whoever made the new version just found a conveniently close grommet to use for the bottom insulator.

[DavidG]

The large washer beneath the motor mount bracket must be tight up against the shoulder on the bolt regardless of how many turns of the slotted hex nut it takes beyond just inserting the cotter pin. There's a reason that the shoulder is on the bolt and why the i.d. of the large washer is snug on the upper part of the bolt. That's assuming that whatever insulators, washers, and bolts you're using are the same as the originals. No doubt some reproduction insulators are too thick or too thin and/or the durometer reading for the rubber is incorrect for this application.

I have found the Drake insulator kits to be true to NOS originals, except for the finish on the steel washers molded into the upper and lower insulator, which were yellow cadmium or brass plated originally.

[Drbrown]

I installed front pad kits from Steele Rubber. The pads, bolts and washers matched what I removed. However, the kits did not include the large diameter "washers" that go on top of the pad assembly so I cleaned-up and reused the existing ones.

During installation, I had to put a small hydraulic jack directly beneath the bolt head and lower the weight of the engine onto it to compress the pads enough to install the castle nuts on top.

At this time, about 3 months later, the pads have compressed under the weight of the engine and vibration has disappeared.

[rich b]

Wonder why Bob Drake lists extra long motor mount bolts on the same page as his repop mounts?

[DocJohn]

Originally Posted by Drbrown

I installed front pad kits from Steele Rubber. The pads, bolts and washers matched what I removed. However, the kits did not include the large diameter "washers" that go on top of the pad assembly so I cleaned-up and reused the existing ones.

During installation, I had to put a small hydraulic jack directly beneath the bolt head and lower the weight of the engine onto it to compress the pads enough to install the castle nuts on top.

At this time, about 3 months later, the pads have compressed under the weight of the engine and vibration has disappeared.

I'm glad you posted this as it's answered my questions of whether I've got the right motor mounts for my Pilot V8 Woodie and how they go together. Thanks to you, I managed to get the reused washers and the new motor mounts installed yesterday.

[oldskool]

I like to use the mounts with the stainless steel bands around the cushion they don't flatten out much with age

[Floyd]

Yeah! Maybe I finally did something almost right. I used Drake mounts and painted the washers with brass paint. (Of course I got the tip from David).
My opinion

[19Fordy]

Here's the way mine look.
Tighten nut until all slack is gone and then go 1 more turn and insert cotter pin.
The threaded bolt on mine extend about 3/16 in. above the top of the castle nut and the cotter pin is in the middle of the castle nut slot. You don't want to "squish" the rubber excessively.
Same with transmission mounts.

[John R]

The Drake mounts are very nice. However, he does not include the small washer (B-6033) that goes directly under the castle nut. At least I didn't get one in the package and it is not shown in the catalog with the other parts in the kit.

[Heard]

Originally Posted by 40cpe

The bottom insulators are thicker than the ones that came off. I had to struggle to get the nuts started on the bolts. I plan to take them out and trim some of the lower insulator off.

This is what I did. The new ones just don't fit properly in my opinion.

[Ritzy1]

I got new motor mounts from Mac's and the bolts have a shoulder that is larger than the hole in the rubber pad that goes below the crossmember. I haven't gotten into it too deep yet, but there's no way to start the nut on the bolt, let alone get the cotter pin in. I just put them in place to test-fit the engine/trans, but I'll need to figure out a way to get that bolt shoulder to fit into the hole in the lower pad. The water pumps are from Drake.

[DavidG]

John R,

I bought some more recently and they are consistent with your experience, namely no upper washer for between the castle/slotted hex nut and the oval hole in the motor mount bracket.

I recently ran across a Company letter of the period to the assembly branches instructing them to ensure that the nuts were to be tightened to their limit (the large washer bottoming out on the shoulder of the bolt) with the bottom insulators bulged outward as a result. What is interesting about that instruction (I don't recall its date, but I'll look for it again) is that to achieve that result, more torque would be required for early '32 and '35 and up applications because of the use of the stamped steel cup in addition to the thickness of the front cross member whereas no cup is used on most '32 and all '33-'34 front cross members. In addition to more torque needed to tighten the nut, the compression of the lower insulator would be that much greater.

[AnthonyG]

Replace the old rubber, the old rubber has shrunk and hardened. You'll find as others indicated the Castle nuts will snug / tighten quite a bit to get cotters in when you get the new rubber mounts. Snugger better than not.

[Drbrown]

As above two alluded to, you have to squish them down like jelly donuts to at least get the cotter's in. Just don't hold your mouth open underneath expecting to catch some tasty drippings.