FJ40 2F Engine Alignment

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Dropped my engine back in the chassis this weekend and can not seem to get it aligned straight - the passenger side is a little forward of the drives side. Measuring off the harmonic balancer, the passenger side is about 1/4" forward of the drivers side.

Questions:

- How straight does it need to be? / What is level of misalignment is acceptable?
- Any recommendations on how to get it aligned?


2F Engine
1981 FJ40

Thanks,

Walt
 

EWheeler

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Dropped my engine back in the chassis this weekend and can not seem to get it aligned straight - the passenger side is a little forward of the drives side. Measuring off the harmonic balancer, the passenger side is about 1/4" forward of the drivers side.

Questions:

- How straight does it need to be? / What is level of misalignment is acceptable?
- Any recommendations on how to get it aligned?


2F Engine
1981 FJ40

Thanks,

Walt
Are we to assume that you are trying to bolt this back up to the bellhousing? No issues there? Did the transmission stay in the truck?
 
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Are we to assume that you are trying to bolt this back up to the bellhousing? No issues there? Did the transmission stay in the truck?

Thanks, should have explained better. Pulled both the transmission and engine, rebuilt, dropped them back in as one unit. Body is off the chassis.

Walt
 

EWheeler

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Thanks, should have explained better. Pulled both the transmission and engine, rebuilt, dropped them back in as one unit. Body is off the chassis.

Walt
Are you able to get all the mounting bolts installed? (assume there are two engine mounts and two mounts on the 4speed bellhousing? or does your 81 have a crossmember under the transmission like the FJ60 does?) Or, are there one or two that won't go in because of the mis-alignment?
 
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Are you able to get all the mounting bolts installed? (assume there are two engine mounts and two mounts on the 4speed bellhousing? or does your 81 have a crossmember under the transmission like the FJ60 does?) Or, are there one or two that won't go in because of the mis-alignment?

The '81 is like the Fj60, there is a crossmember under the transmissions. Transmission mount goes in without a problem.
 

EWheeler

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Engine and trans were from the cruiser. New motor mounts on engine and tranny.
I'm sorry, but it is still not clear what the issue is. Do you have measurements from the harmonic balancer from before removal? I'm assuming no, most of us, myself included, don't think to baseline everything before disassembly. Are the bolts not dropping in? Or are you concerned purely based off the dimensions taken from harmonic balancer. What is your reference you're measuring to? Just so everyone has a clear picture - you are measuring from 3 oclock and 9 oclock on harmonic balancer, measuring forward to a reference line assumed perpendicular to frame centerline? (probably the crossmember in front of the engine?) Pictures really help....
 
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I thought the engines were slightly off-center on purpose?


Side to side yes. Why the passenger side on LHD have more foot room. That way because of the offset on the transfer case. Front to back not sure. I would use a square and be sure all the four corner angles match the opposite side. Frame tweaked a little could cause this. Impact on just one side could tweak the frame enough that everything bolts up but just not evenly.
 
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I'm sorry, but it is still not clear what the issue is. Do you have measurements from the harmonic balancer from before removal? I'm assuming no, most of us, myself included, don't think to baseline everything before disassembly. Are the bolts not dropping in? Or are you concerned purely based off the dimensions taken from harmonic balancer. What is your reference you're measuring to? Just so everyone has a clear picture - you are measuring from 3 oclock and 9 oclock on harmonic balancer, measuring forward to a reference line assumed perpendicular to frame centerline? (probably the crossmember in front of the engine?) Pictures really help....

- Didn't take a baseline measurement, never even thought of doing that. Thanks for the future recommendation.

- All the bolts are dropping in, not a problem with mounting.

- I am measuring from two reference points at the 3 and 9 position on the harmonic balancer. One reference is forward to the frame and the second reference using a straight edge between the shock mounts.

- My concern is purely based on the dimensions taken from the harmonic balancer. It does look a little off center with the fan installed.

- Wanted to address the possible problem before I finished installing and run the engine.
 

EWheeler

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- Didn't take a baseline measurement, never even thought of doing that. Thanks for the future recommendation.

- All the bolts are dropping in, not a problem with mounting.

- I am measuring from two reference points at the 3 and 9 position on the harmonic balancer. One reference is forward to the frame and the second reference using a straight edge between the shock mounts.

- My concern is purely based on the dimensions taken from the harmonic balancer. It does look a little off center with the fan installed.

- Wanted to address the possible problem before I finished installing and run the engine.

If all the bolts are dropping in, I would not have any concerns personally. I think you're worrying about an issue that doesn't exist. If you don't have baseline measurements from a known true and square frame, the data you have is not really good data. As mentioned earlier, it's possible the frame is not true and square. I would be more concerned about squareness of the axles to the frame centerline, than the alignment of the motor in the frame. U-joints will account for any slight misaligment of the engine if there is any. Sure, if it's really wonky you'll need to ensure proper clearance from the fan to the shroud.
 

pjohnson

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Is there any side to side wiggle room at the cross member? It could easily account for 1/4" at the other end (harmonic balancer).

As I recall, there is a little play in the engine mounts as well. I would suggest just do your best to square it up and move on.
 
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If all the bolts are dropping in, I would not have any concerns personally. I think you're worrying about an issue that doesn't exist. If you don't have baseline measurements from a known true and square frame, the data you have is not really good data. As mentioned earlier, it's possible the frame is not true and square. I would be more concerned about squareness of the axles to the frame centerline, than the alignment of the motor in the frame. U-joints will account for any slight misaligment of the engine if there is any. Sure, if it's really wonky you'll need to ensure proper clearance from the fan to the shroud.

Never thought about the frame being bent. My guess that a 40 year old vehicle has had a few bumps along the way. Gonna check that this weekend.

Thanks to everybody for the help.
 

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