Motor Mount Replacement
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
It's a real tight squeeze, but I managed it for a few years. I couldn't crawl completely under, but just enough to reach most of the engine parts. Lots of times I had to exhale to slide in. I don't know if I could still do it because I've put on a lot of weight, but I can still snake my arms far enough under to reach the oil plug.
6'2, 250, no way in hell I'm getting under there. I can get slightly under the spare tire carrier and that is IT. I did do my header collector bolts and nuts with the car on the ground, but long arms account for ALL of that.
On the subject - I installed ES polys a few years ago and like em a lot.
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 1,012
Likes: 5
From: Granbury, TX
Motor mounts are like belly buttons, everybody's got 'em.
I did the swap last night using solid mounts from Summit
http://store.summitracing.com/partde...0&autoview=sku
a mere $25.88 plus handling charge.
I lifted the motor slightly using a floor jack and 2 X 6 on the pan near the front where it transitions over the crossmember to the deep part of the pan.
The right side was easy, it took less than 15 mins. The left side was more difficult as I had to remove the left side header to get access to the through bolt. This meant removing plugs, wires etc also.
I was happy to see the left side mount had completely separated so my diagnosis was correct.
All the bolts came out easily, I did not have to remove or loosen the tranny mount. While the motor was slightly lifted, I started all the bolts and threaded in about half way before lowering the motor and final tightening.
There is a slight vibration I can feel in the steering wheel and in the floor pan. It is not objectionable and probably not noticeable to anyone not familiar with the car. Over all I am pleased and it's good to know this should be the last time I need to take on this project.
I did the swap last night using solid mounts from Summit
http://store.summitracing.com/partde...0&autoview=sku
a mere $25.88 plus handling charge.
I lifted the motor slightly using a floor jack and 2 X 6 on the pan near the front where it transitions over the crossmember to the deep part of the pan.
The right side was easy, it took less than 15 mins. The left side was more difficult as I had to remove the left side header to get access to the through bolt. This meant removing plugs, wires etc also.
I was happy to see the left side mount had completely separated so my diagnosis was correct.
All the bolts came out easily, I did not have to remove or loosen the tranny mount. While the motor was slightly lifted, I started all the bolts and threaded in about half way before lowering the motor and final tightening.
There is a slight vibration I can feel in the steering wheel and in the floor pan. It is not objectionable and probably not noticeable to anyone not familiar with the car. Over all I am pleased and it's good to know this should be the last time I need to take on this project.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
That's the unhindered power of the beast you feel. It's something you will come to love.
Did you notice any differences in how it feels when you get on it? Does it feel like it responds quicker?
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Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 1,012
Likes: 5
From: Granbury, TX
I can’t say there is a noticeable difference in power but she is responsive when I jump on her and it’s much better than the vibration I was getting from the motor torquing over and jamming the exhaust against the floor pan.
Intermediate
Joined: Mar 2009
Posts: 41
Likes: 0
considering changing motor mount on my 73 sb. Does anyone known if the poly or the solid mount lift or lower the engine from its original position, have a vbp spreader bar installed and have very little clearance under fan hub to consider.
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 1,012
Likes: 5
From: Granbury, TX
You should be able to shim between the mount and the frame a bit if you need to. Are you having problems lining up your drive train?
As long as everything is properly positioned (not in a bind) and you are not stressing your fame, mounts etc., the solid mounts should contribute to frame stiffness with no issues.
As long as everything is properly positioned (not in a bind) and you are not stressing your fame, mounts etc., the solid mounts should contribute to frame stiffness with no issues.
Intermediate
Joined: Mar 2009
Posts: 41
Likes: 0
no alignment problems just thought by shimming i could get a little more distance between the fan hub and the spreader bar. right now i can put the width of 2 hacksaw blades between them not really sure if that is enough room.Don't really know how much the engine travels up & down, i understand that it twists right to left
Melting Slicks
Joined: Feb 2001
Posts: 3,330
Likes: 13
From: Europe , Luxembourg
Hi
There are some threads about melted poly motor mounts and I saw one on a 65 racecar with a clone L88 motor .
If the exhaust headers are too near to the poly mount, the poly simply melts away.
Rubber does not melt, nor does solid mounts.
I am presently still running the old rubber mounts with the HOOKER side pipe headers on my BB 68 without any problems.
There is a modification that can be done to the mount by drilling a hole through it and installing a bolt loosely in order to stop any up movement of the engine in case the mount rubber or poly breaks.
I am kind of afright that a solid mount could crack the engine side wall. The material is not really thick there, is it ?
Rgds. Günther
There are some threads about melted poly motor mounts and I saw one on a 65 racecar with a clone L88 motor .
If the exhaust headers are too near to the poly mount, the poly simply melts away.
Rubber does not melt, nor does solid mounts.
I am presently still running the old rubber mounts with the HOOKER side pipe headers on my BB 68 without any problems.
There is a modification that can be done to the mount by drilling a hole through it and installing a bolt loosely in order to stop any up movement of the engine in case the mount rubber or poly breaks.
I am kind of afright that a solid mount could crack the engine side wall. The material is not really thick there, is it ?
Rgds. Günther
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 1,012
Likes: 5
From: Granbury, TX
no alignment problems just thought by shimming i could get a little more distance between the fan hub and the spreader bar. right now i can put the width of 2 hacksaw blades between them not really sure if that is enough room.Don't really know how much the engine travels up & down, i understand that it twists right to left
Intermediate
Joined: Mar 2009
Posts: 41
Likes: 0
Thanks for all the input. I plan to go solid with motor mounts and poly trans mount.
Can anyone give me any tips on how to replace that trans mount. Do I need to remove
the crossmember or can i just jack up the trans to r/r the mount
Can anyone give me any tips on how to replace that trans mount. Do I need to remove
the crossmember or can i just jack up the trans to r/r the mount
Last edited by kwikcc; Jan 8, 2011 at 11:51 PM.
Intermediate
Joined: Aug 2010
Posts: 43
Likes: 1
'70 small block motor mount replacement
Okay. 2x8 under oil pan is jacked up; weight is off the mounts; tranny mount bolts are loose, all (6) motor mount bolts are out. On passenger side , the mount has separated but won't come out. Why can't I remove the mounts? What's with 'self locking'? What am I missing here?? Thanks.
Thread Starter
Burning Brakes
Joined: Jun 2004
Posts: 1,012
Likes: 5
From: Granbury, TX
Are you sure you have all the bolts out? Did the one on the right side come out? Check all the bolt holes on the mount you removed and on the new mounts and double check the bolts are accounted for on the left side. If so it may just be stuck with years of accumulated crud. Carefully pry it off with a pry bar or large screwdriver. Good luck
Intermediate
Joined: Aug 2010
Posts: 43
Likes: 1
Are you sure you have all the bolts out? Did the one on the right side come out? Check all the bolt holes on the mount you removed and on the new mounts and double check the bolts are accounted for on the left side. If so it may just be stuck with years of accumulated crud. Carefully pry it off with a pry bar or large screwdriver. Good luck