Installing new engine, motor mount issue
Thread Starter
Racer
Joined: Jan 2006
Posts: 256
Likes: 0
From: Norfolk VA
Installing new engine, motor mount issue
I went to drop in my 383 yesterday with the transmission and headers already installed. I bought a set of cheap mounts from autozone figuring I might change them later because I have no idea how they'll hold up, but when I put it in I couldn't get anything to line up. I used a leveler to level the engine and trans with my crane, but it seemed like I couldn't get the mount down far enough. After some prying and working with it I finally got one bolt in after removing two of the three engine side bolts. I got one back in, but the other isn't (I'm sure I could, but I was doing this for 6 hours and quit at 11pm). The other side has all 3 engine bolts loosely on, but the main frame bolt is only on half way. I had to give up for the night. My uncle said they had a late 70's that did the same thing. Is there some trick to this, did I bend the mounts, or are they just crappy parts to begin with?
Limping across the line
Joined: Oct 2002
Posts: 5,299
Likes: 109
From: Peoria Az
Chances are you have a set of mounts for a 307 engine.
Let me guess they are snug going over the mount & then are about half a hole off for getting the bolt through.
This has happened more than you care to know. I found out the hard way on this years ago with a TPI El Camino I built.
Do yourself a favor go to a quality source for your mounts
Let me guess they are snug going over the mount & then are about half a hole off for getting the bolt through.
This has happened more than you care to know. I found out the hard way on this years ago with a TPI El Camino I built.
Do yourself a favor go to a quality source for your mounts
Team Owner
Joined: Oct 2004
Posts: 23,831
Likes: 10
From: Springfield MO
St. Jude Donor '07
I recently installed a set of Moroso's solid mounts. Among other things, I had to use a big bolt and nut to spread the ears a bit before they'd drop over the frame horns.
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
they do take some effort to get to fit..use some grease ...loosen the bolts on the engine use a prybar in the hole to help align them and try putting a floor jack under the engine to take some weight off of it....we had success when we used the floor jack....it seemed to make wiggling the engine easier....and then all of a sudden its in place.. you can alwys put a smaller diameter bolt in place through one of the motor mounts just to help align things and then remove it and replace with the proper bolts.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I don't know if this is your problem or not.
But a few years ago I bought Energy Suspension Poly locking motor mounts from Summit Racing. They would not fit down over the frame mounting points. I even tried to pound them on.
What my problem turned out to be is that the gold anodizing actually added enough material the I had to grind the inside of the motor mount for clearance
But a few years ago I bought Energy Suspension Poly locking motor mounts from Summit Racing. They would not fit down over the frame mounting points. I even tried to pound them on.
What my problem turned out to be is that the gold anodizing actually added enough material the I had to grind the inside of the motor mount for clearance
Last edited by gkull; Jun 14, 2007 at 02:45 PM.
Le Mans Master
Joined: Oct 2004
Posts: 5,269
Likes: 54
From: Orlando Florida
St. Jude Donor '05
You can bend the engine mounts and open them a little.. makes it a LOT easier to install them. When you tighten the bolt that goes thru the frame horn it will clamp the engine mount tight on the frame....
Burning Brakes
Joined: Jan 2007
Posts: 1,057
Likes: 4
From: Concord Calif
I went to drop in my 383 yesterday with the transmission and headers already installed. I bought a set of cheap mounts from autozone figuring I might change them later because I have no idea how they'll hold up, but when I put it in I couldn't get anything to line up. I used a leveler to level the engine and trans with my crane, but it seemed like I couldn't get the mount down far enough. After some prying and working with it I finally got one bolt in after removing two of the three engine side bolts. I got one back in, but the other isn't (I'm sure I could, but I was doing this for 6 hours and quit at 11pm). The other side has all 3 engine bolts loosely on, but the main frame bolt is only on half way. I had to give up for the night. My uncle said they had a late 70's that did the same thing. Is there some trick to this, did I bend the mounts, or are they just crappy parts to begin with?
Sounds like your trying to bolt the mounts to the engine after they are on the frame horns? Cause there is only one bolt per side that attachs the mount to the frame and three that attach the mount to the engine. Ok long winded here, Bottom line, have the mounts tight on the block before setting into place on the frame. Then procede as others have noted below about putting the one bolt per side in. Hope that is a little clear.
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Melting Slicks
Joined: Oct 2004
Posts: 2,662
Likes: 8
From: Knoxville Tennessee
Don't use the rubber mounts. You will just rip them apart. Go with solid mounts. Besides lasting forever, they stiffen the front end, which is needed on a C3 and you do not get any vibration inside the car.
Bernie
Bernie
Team Owner
Joined: Oct 2004
Posts: 23,831
Likes: 10
From: Springfield MO
St. Jude Donor '07
As things ended up, the paired motor mounts are solid, the paired rear crossmember mounts are solid, and the single transmission mount and front differential mount are poly. Should be nice and tight.
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Install the three bolts on both sides loosely, drop the motor in, wiggle it around ( on a chain or with a floor jack ) until the two long bolts one each side line up and you can put them through, then tighten the 6 bolts, presto chango done 
Melting Slicks
Joined: Apr 2002
Posts: 2,337
Likes: 14
From: Norfolk VA
I bought new motor mounts from Zip in 2002 and they did not fit at all. I sent them back and ordered a pair from the Chevy dealership and blam...they fit perfectly, holes were lined up to easily slide the long bolt all the way through. In some cases oem equipment can save you some time.
Race Director
Joined: Nov 1999
Posts: 10,643
Likes: 8
From: Foxfield CO 1970 Convertible
I got the energy suspension polyurethane mounts from Autozone. Using Motorhead's method (all bolts loosely installed, then tighten afterwards) it only took about 5 minutes per side to get the engine installed. 
Le Mans Master
Joined: Oct 2001
Posts: 5,943
Likes: 3
From: Wildwood IL
Presto 
...took me 5 minutes to torque it down using this method. Eddie
Thread Starter
Racer
Joined: Jan 2006
Posts: 256
Likes: 0
From: Norfolk VA
Apparently a clear head, some better light, and bolting the tranny to it's mount first was the ticket. I went back and put in the tranny crossmember and mount, then went back and putting the bolt in the block was easy. The other side didn't take me much longer to get the bolt through. I loosened the block bolts then pushed down on it and ever so lightly (sure), tapped it with a hammer. Once it started I just used the threads to pull it through. Thanks for all the help guys. My engine is looking beautiful in there and has the new valve cover adapters and covers on, the carb and the distrib in. I've got some more questions, but I'll make another post.
