The Stovebolt Site Forums The Shop Area Engine Shop 50 Chevy 216 front motor mount in a 3100 truck

When I pulled the 216 out of my 50 Chevy 3100 truck, I hand to unbolt two (or maybe four) front motor mount bolts that that went through the front frame cross member. For the two center bolts (with large holes), it seemed like there were two rubber washers (or maybe like donuts) that were underneath the frame where the nuts were. It was hard to tell with 60 years of gunk packed on the frame and whatever it was was completely rotted. The frame has two small holes and then two large between the small holes. Is there supposed to be a frame bushing between the frame and the bottom of the motor mount tray or does the motor mount just bolt directly to the frame? Don't know why the center holes are so large. Don't know if I can post pictures.

this is a quote from engine manual 6-13 engine assembly.
The washers on the middle bolts that are in the front mount must cover the metal sleeve inside the rubber cushion, but not touch the cross member. GM specs are for 13/16" OD.
the holes are larger so nut washer is not touching frame.
just learning this as i am trying to put a 48-50 engine
in my 58.cant find all peices only new rubber mount
and new top cover peice.

rwb - Thanks for the info. I should have paid more attention when I was unbolting the front mount. By the way, have you looked through Ebay for parts you need. Seems like I saw a lot of engine mount pieces, plus lots of other truck/engine parts. I found a number of engine parts for my 216 overhaul on Ebay.

I think I figured it out (maybe?). There are two engine mount plate bolts that go down through the metal mounting bushings, which then go through the two inter large holes. These bolts hold the engine mounting plate to the front mount and flex with the rubber support bushing. The other two bolts, which go through the outer small holes, hold the engine mount to the frame. So the inner two are engine to mount bolts and the outer two are mount to frame bolts. I have a picture, but I don't know if I can upload it.

DADS50 - Thank you vry much for the link and other postings. If I had the time, patience, and strenght, I'd like to to a stock off-frame restoration. The link for the mount was excellent. It confirmed what I thought. The 50 we have was originally bought by my wife's great-grand parents for orchard work. It then went to her grand father, who used it in his orchards. After they sold the orchards, it sat in their garage for years and then given to my wife's mom. It then sat in her garage for years and was then given to my wife. We've had it since 2009. My wife remembers riding in it when she was a kid, so I'm restoring it for her. I and a friend are currently overhauling the engine (bad crank flywheel mounting flange). When we're done it should be like a new engine. Thanks again for your post.

The link is from Denny Graham's web site.

I have it bookmarked and reference it often.
His 50 is a 3600 and he has some of the best pic's around

DADS50 - P.S. I forgot to ask if the truck in the video is yours? Great looking truck an a great video. Nice stock restoration. That's what I'm doing with our 50. A clean stock restoration.

D Winn -

If you need new hardware, I listed original GM part numbers and Fastenal equivalents when I recapped my motor mount installation in this post. NOTE >>> My photo of the underside of the cross member is WRONG because it has the thick flat washers mounted on the bottom of the cross member instead of between the retainer and the cross member.
> My post w/incorrect placement of spacer

As posted previously by DADS50 -
> Bottom view - CORRECT PLACEMENT of nuts and washers. (Denny Graham)
> STAND OFF WASHERS between retainer plate and cross member. (Denny Graham)
> Factory Assembly Manual - poor reproduction is difficult to see placement of stand off washers (GM #365685 3/8" ID, 1-1/4" OD, 0.187 thick)
> Denny's description of the standoff washer

Yes, the truck in the video is mine.(my Dads old truck). Thanks for your comments.
Not a real restoration, mostly a rattle can rebuild. I was going for the garage build 70's ERA look

Good luck

LonnieC - Thanks for the info, links and pictures. Now I more fully understand the mount setup. Like I said in the beginning of the post, the front mount and bolts were covered with 60 years of gunk. I had to scrape the old mount cushion out of the retainer. After 60 years it was like it was melted or glued to the retainer.

If you can't find the missing parts PM me.

Pre 68 Dave - Thanks for the offer. Awhile back I purchased the replacement rubber mount cushion and the two rear mounts. The mount cover, top plate and retainer were in good shape. As I mentioned above, I had to pry the old rubber mount cushion out of the retainer after 60+ years. Looked like it had melted in place.

A related issue - Now that the engine is back together, I was looking at the front mount again before installing it. I noticed that mounting plate carrage bolts, like all other carrage bolts, have a square shoulder beneath the carrage head. When I put the bolts through the two square holes in the engine mounting plate, the square carrage bolt shoulder sticks down about a 1/8" or so below the mounting plate surface. If I were to install the mount, it would seem that the square carrage shoulder would be directly on the top edge of the sleeve bushing in the rubber mount, which would result in a gape between the top of the sleeve bushing and the bottom of the mount plate on the engine (hope that makes sence). Should there be a washer there as there is on the bottom of the bolt where you install the castle nut? By the way... someone hacked the oil seal cover plate to where the two holes are slightly bigger that the sleeve bushings. Not sure why.

Are you talking about the shield that goes over the rubber
mount? that should have a 7/16" hole in it with just enough
clearance for the 7/16" bolt to go thru. The original inner
bolts were swaged into the front plate from the bottom and were
not meant to come out. Are the "carrage bolts" that you're
using the hardware store variety of are they the original ones?


DG

As fr the oil shield, someone drilled or cut it to be slightly wider than the Rubber mount bushing. Maybe the problem is that there's no metal surface between the shoulder of the carrage bolt and the top of the bushing. Guess I need a new oil plate. What I was trying to get at is the mounting plate on the front of the engine has two square holes for the inner carrage bolts that go through the mount bushings. When I removeed the mount assembly from the mounting plate the inner carrage bolts came out easily. The bolts appear to be original, or from that era, and have the castle nuts. When I stick the inner carrage bolts throung the square holes in the engine mounting plate, the shoulder of the carrage stick out about a 1/8" past the bottom of the engine plate. If I install the mount, the exposed carrage shoulder is in contact with the top of the bushing (I guess because of my modified oil shield). When I bolt in the mount it seems very loose up against the shoulder of the carrage bolt. Just to see, I put a large washer on the carrage bolt before putting the bolt through the engine mount in order to make the bottom of the carrage bolt shoulder flush with the engine mount plate. The when I installed the mount assembly and bolted it up it was tight. This is my first 216 overhaul so I'm not sure about the mount installation specifics beyond what is in the manual. I saw your photos for the lower end of the mount, but I'm not sure how the top of the monut is suppossed to fit with the mounting plate. How do I post pictures?

Are the center bolts should be a 7/16"x 20, fine thread bolt?
DG

Yes, and they have holes at the ends for cotter keys to hold on the castle nuts. I went out and installed the mount to the mounting plate on the engine. Once I tightened the two 7/16 bolts, there was a 1/8" or so gap between the oil shield and the bottom of the mounting plate. The gap was because of the shoulder of the carrage bolt against the oil shield and bushings. Is the oil shield and the tops of the bushing supposed to be tight against the mounting plate without a gap or should there be a gap? I looked at the old bushings and it looks like the bottom of the carrage bolt was riding against the top of the bushing (As I mentioned, someone cut the top of the oil shield to expose the top of the bushings.

Hi Denny, Thank you for your assistance. I just now looked at your pictures on your web page. In the first picture it looks like the top of the mount and oil shield, are tight up against the bottom of the mount plate. When I was looked at the carrage bolt pictures, the depth of the carrage shoulder seems to be less. Are your bolts the original factory bolts? I'll try to link some pictures of mine.

http://www.pbase.com/dennygraham/1950_motor_mounts&page=all

Yes they are the ones that were swaged in to the plate at the factory.
DG

Let's see if this photo link works!

Image 01 is the mount in place. You can sort of see the gap
Image 02 is a picture of the castle nut on the bottom. Doesn't seem to be much tread
Image 03 you can see the gap between the plate and the mount
Image 04 is of the bolt sitting in the mounting plate
Image 05 show how the bolts sit against the bushings
Image 06 Just a picture of the bottom of the bolts
Image 07 Just another pic of the mount and you can see the bucthered oil shield above.

Don't know if I'm supposed to have that gap between the plate and the mount.

http://s1353.photobucket.com/user/d...mp;_suid=1367424761428048769450502811157