Engine mounts

[Bitsyncmaster]

Is there something on the block "ear" that stops the through bolts from going below the lowest slot cut in the engine mount? Just wondering if I should jack the engine up a little before I tighten the nuts on those through bolts.

[dn010]

I don't think so, maybe "ear" to mount contact might stop it but having just installed an engine on new mounts, the bolt is always resting on the bottom of the slot and I tightened them that way.

[Bitsyncmaster]

I don't think so, maybe "ear" to mount contact might stop it but having just installed an engine on new mounts, the bolt is always resting on the bottom of the slot and I tightened them that way.

Well my drivers side I can pull the bolt out without lifting the engine. The passenger side is sitting on the bottom but that through bolt is frozen.

[Bitsyncmaster]

I looked with a mirror and the engine casting is defiantly sitting on the motor mount steel. My passenger side is frozen. When I lift the engine the mount rubber just wants to pull apart.

[Bitsyncmaster]

Well the passenger side broke fee. I just jacked the engine up till the rubber was pulling and hit the mount with a hammer and it broke fee. I did tighten the through bolts higher (where the large flat washer just hits the top of the mount). Not sure if it will stay there since it's only friction where the mount clamps onto the block.

This was all started when I decided to replace the engine mounts, just because they are 43 years old. I figured I would just start to see if the two frame bolts would be free. Well that was a problem on the passenger side lower bolt (it would not move). I decided to order a 6 point 13 mm boxed end wrench because I did not want to round the head on that bolt (there is no room to fix it). With a hammer at the wrench I did get it to move a little. It was very tight all the way out and needed a pipe on the wrench. The top bolt came out with a 6 point 1/2" drive socket.

The through bolt is frozen in the block so that is staying in there. The drivers side through bolt just pull right out with my fingers.

Now to change the mounts you have to lift the engine quite high to clear the mount. But to do that your exhaust tips will hit the rear bumper. So you either have to remove the muffler or pull the bumper. I decided to wait on replacing the mounts. I may be installing EFI and that would require changing the crank pulley which does require removing most everything on the back side.

But while I was in there. It seems the passenger side motor mount is where most people have the problem with a frozen bolt. I'm thinking that problem may be caused by the engine ground jumper attached on that mount. That is a high current circuit with the starter and alternator currents.

I bet that is why my lower frame bolt was corroded. That stock ground jumper drives all that current threw the bolt if the metal on the frame and mount is not clean. Was that part of the frame epoxy coated?

I will post some photos of a fix I made later.

[Bitsyncmaster]

Here are my new engine grounds.

[Bitsyncmaster]

I keep wondering if the designers intended on the motor mounts not supporting the motor on the through bolt. I guess it does not matter from anything I can think of. You still need the through bolt to keep the motor from lifting with engine torque.

[dn010]

You still need the through bolt to keep the motor from lifting with engine torque.

I don't think these engines don't produce enough to move, I drove for years without the bolts/nuts tightened on my mounts (ground strap was not tightened but I have a ground bus going to the engine and ground straps going from frame to valve cover on each side as Volvo had it on the Bertone) and there was no evidence of movement.

I also changed my mounts because they were old and the engine was already out, so, why not. Interestingly, they left the part number sticker on the bottom of my original mounts which was kind of neat to see. I noticed that the new mounts did not line up with the bolts on the ears of the engine, I kind of had to force the engine in place and I'm sure the new mounts will eventually settle. Hopefully yours will go right in without issue.

[Bitsyncmaster]

Is there something on the block "ear" that stops the through bolts from going below the lowest slot cut in the engine mount? Just wondering if I should jack the engine up a little before I tighten the nuts on those through bolts.

Well I tightened the through bolts with the engine lifted so the large washer was at the top of the mount. I took it for a drive and it looks like the drivers side has dropped back down till the block ear stops it from falling any more. The passenger side dropped a little also. So if you want to keep the block from dropping you would need to weld the slots up maybe a 1/4" or 1/2". I guess the friction does not hold it.

[dn010]

Just curious as to why you'd want to raise the block up to begin with.