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Rzeppa
10-05-2009, 07:34 PM
Coming home yesterday, there suddenly was a horrible sound coming from my 71 FJ40, in tune with RPMs but only under power. Visual inspection after returning home revealed where the orange metal fan blades had been in contact with the inside edges of the fan shroud.

Without even doing the usual diagnosis of jacking up under the oil pan I knew that my left motor mount was probably torn. Hey, it's only 38 years old, but sometimes they get torn.

I have a spare (thanks Chris Hatfield!) off an FJ60. The stock old school (discontinued) hockey puck style front motor mount uses a bolt on top and a stud underneath. Which requires less clearance to replace. The newer style has a stud on both top and bottom, which will require at least an inch or two more clearance to get in there.

So my questions are about lifting the engine enough to put the new motor mount in:

Is it possible/reasonable to jack the motor up enough with a floor jack under the oil pan? The top motor hook is on the other side of the engine, will putting a cherry picker on that hook help even if lifting on the other side of the engine? How much will I need to loosen the right side motor mount to get enough clearance to replace the left side front mount with the studs on both top and bottom?

I've done this many times when installing engines, but am trying to plan things out for a minimum of disruption/disassembly. Basically looking for advice from anyone who has replaced front motor mounts in an F series in situ.

Thanks and happy cruisin'!

jettaglxdriver
10-05-2009, 08:28 PM
You want help doing this this week? I'm looking for an excuse to drive up in the hills.

SteveH
10-06-2009, 10:46 AM
I would use the lifting hook, as extensive jacking on the oil pan can break the spot welds between the pan skidplate and pan. You may have to loosen the other 3 motor mounts, but I'd easily see the room you need to slip in the new one. A criticism of the old mounts is that they are not captive and when they break, and set the engine free to move more than you'd like. So, later mounts are good. As you lift the engine, look for ground wires, fuel hoses, etc. that appear to be approaching banjo-string tension - and handle those as necessary.

Steve

MDH33
10-06-2009, 11:01 AM
I would recommend replacing both front mounts at the same time. This will make lifting the front easier and save you time down the road when the other fails. I did this on my '73 using the new OEM FJ60 (square, captive) style.

Air Randy
10-06-2009, 11:20 AM
I replaced mine with the new style mounts. I only had to lift the motor enough to take the weight off of the mount. I then removed the bolts that hold the bracket to the engine block. Then you have plenty of room to replace the rubber mount.

Trapper50cal
10-06-2009, 11:54 AM
I replaced mine with the new style mounts. I only had to lift the motor enough to take the weight off of the mount. I then removed the bolts that hold the bracket to the engine block. Then you have plenty of room to replace the rubber mount.

This is what I did as well. Taking the "dog ear" or bracket of the block meant not having to raise it enough to clear the pins in the motor mount. Just take it all out, replace the mount, put it back together then re-install.

Rzeppa
10-06-2009, 07:53 PM
I would recommend replacing both front mounts at the same time. This will make lifting the front easier and save you time down the road when the other fails. I did this on my '73 using the new OEM FJ60 (square, captive) style.

The passenger side was already replaced with newer style in '06 when I set this engine in there. Scott Yoder and I had a fun time that night :-)

Rzeppa
10-06-2009, 07:57 PM
I replaced mine with the new style mounts. I only had to lift the motor enough to take the weight off of the mount. I then removed the bolts that hold the bracket to the engine block. Then you have plenty of room to replace the rubber mount.

Hi Randy, it is more than taking the weight off, it is also clearing the studs. The olde style hockey puck mounts have a bolt on the top and a stud on the bottom. Because the newer style ones use a stud on both top and bottom, it will require more clearance between the ear of the motor mount and the matching mount on the frame.

I think I'm going to try to tackle this tonight, TLCA BOD emails and the time they take be damned. :-)

Rzeppa
10-06-2009, 07:59 PM
This is what I did as well. Taking the "dog ear" or bracket of the block meant not having to raise it enough to clear the pins in the motor mount. Just take it all out, replace the mount, put it back together then re-install.

Awesome idea Trapper! I might just run with that! Thanks goodness for the 1971's lack of smog junk in that area, making for lots of access.

leiniesred
10-06-2009, 09:32 PM
Jeff: I would put a wooden 4x4 on the jack to spread the load a little and jack it up on the oil pan. No problem. I mean you set those engines down on the ground on the pan all the time, right? Even point loaded on angles I've only seen pans crushed in on a corner or if the drain plug is lower than the rest of the pan.


J

Rzeppa
10-07-2009, 12:02 AM
Jeff: I would put a wooden 4x4 on the jack to spread the load a little and jack it up on the oil pan. No problem. I mean you set those engines down on the ground on the pan all the time, right? Even point loaded on angles I've only seen pans crushed in on a corner or if the drain plug is lower than the rest of the pan.


J

That is actually plan A, except I use chunks of landscape timbers (somewhere around 6x6 or 8x8) for stuff like this and suspension work. These pans really don't get buggered too easy from simply force, heck the pan skid plate is at least 3/8 or so.

Thanks Stephen!

Jacket
10-07-2009, 10:39 AM
I'm glad to hear some endorsement of the "piece of wood under the oil pan" technique, since that's probably what I would have done.

Rzeppa
10-07-2009, 07:21 PM
I'm glad to hear some endorsement of the "piece of wood under the oil pan" technique, since that's probably what I would have done.

I've got one under there right now, and sure enough, the motor mount is torn. I'm going to skip the meeting this evening to work on this tonight. I have everything I need, except time - meeting? - Repairing my cruiser? Tonight I'm doing the latter. Miss you guys!

Rzeppa
10-08-2009, 08:26 PM
Follow-up. I replaced the motor mount last night so I would be able to drive her in the snow to and from work today.:thumb:

All is well in the motor mount world, again, many thanks to Chris Hatfield for generously donating to the cause so I had a spare ready to go. The FJ60 style mount went in with no problems, and the suggestion to dismount the ear from the block was spot-on and helped immensely. :risingsun:

A little problem came up today driving home from work, the engine was running rough and during the drive I was thinking either fuel starvation or vacuum leak. Popped the hood when I got home and lo and behold, the PCV line was unconnected from the manifold. I had not disconnected it for the repair but am sure I probably knocked it off when I was taking the air cleaner housing off to get at the motor mount.

Gotta love those easy fixes!