F135 crankshaft main bearing shims

[Heirloom]

I am preparing to rebuild a 1966 F135 motor. The Engine FSM states that shims should be installed with the main bearings. Searching on MUD indicates that not shimming the mains will cause engine seizure and possible crankshaft damage.

In hopes to make sure the engine is assembled correctly, I contacted SOR technical support and asked about the shims. New are DISCO, but used are available from their site. The reply I got was to refer to the FSM for correct guidance to determine correct shim size.

Then, I go to my 1966 "F Engine Repair Manual" (FSM) and look in the section about assembling the crank for proper shimming procedure. The manual states, "Install the shim, lower halves of the main bearings into the bearing caps." This is on page 2-30, "assembling the crankshaft" Thanks again, MUD, for the FSM download!

Here is my question: are there actually different sized shims? Do I need to look in a different part of my FSM for guidelines on determining the proper shims?

-or-

Is there only one shim size? If so, I can just reinstall with the shims that I already have. SOR doesn't sell new shims anymore, only used ones. There is no indication on their site that I would have to order shims based on their thickness, just a $30 bag of main bearing shims.

Here is a snippet from the FSM for you to read what I read.

 

[FishTacos]

bump for a fellow first time F engine builder.

(I'm also curious about this BTW)

 

[Heirloom]

I just measured all my old shims. They were all consistent at about .008".

I am leaning toward the conclusion that all shims are created equal, in this case.

 

[MoCoNative]

There are different sized shims, the stock shims should have a thickness printed on them. The shims are there to make the crank shaft journals round. I was told many years ago, that F blocks were cast in one piece and the main bearing caps were cut back off. The shims take up the space where the material was removed by the saw. Without the shims the main journal hole will be out of round, or otherwise squished. When replacing the bearings on a reground crank, etc... you put in the new bearings, set the crank and then put on the cap with shims. Best bet is to start with the originals for each cap, so label the ones you took off, because they are probably specific to their location. Then torque it down with plastiguage in there. If the plastiguage is at the correct reading, then you are good. If too loose then you need a thinner shim, too tight you need a thicker shim. The factory assortment when available came with different thicknesses for each cap. The rear shims, and maybe the front shims, (can't recall right now,) are unique, as the caps are different than the middle two of course, especially the rear cap of course.

What I have never been clear about is if the shims are truly reusable. I was told once long ago that they are not, once compressed they were compressed. But that does not make sense to me, and I think as long as you get the proper bearing clearance with the plastiguage you are set.

I know on my engine, a scam of an engine builder did it and he claimed that the bearing clearances were good on the tight side of spec. We started the engine for initial breakin, ran it for an hour, then shut if off and went to restart. She was seized pretty hard. Dropping the oil pan and opening the oil filter revealed we had shaved all the babbit off the mains. Totally destroyed the bearings, crank, and dirtied the engine. The rebuilder fixed it, but it has always had some issues ever since. If I had known more at the time, I could tell you more. But that was back in highschool. I honestly don't know if he didn't shim it properly, forgot the shims or what.

I later put another reground crank in that engine for another reason, (that turned out to be bogus) and was able to shim it properly and had no issues doing the work myself.

The spread on the plasitguage tolerance, or the bearing clearance is pretty wide on a 1F, so your shims may be fine with new bearings. I sourced my last set of correct bearings from NAPA. Man-A-Fre had provided the reground crank I put in and sent the newer style bearings, upon complaining to them about it, they said they couldn't get the right ones, I never could figure that out, as I got a set at NAPA, no problem. That was over 10 years ago, but I think NAPA still showed them on their website recently. This was all work on a 4/73 F155, but I think the F135 is pretty much the same.

 

[Heirloom]

Thanks! I was planning on going back together with the original shims and plastigague to see what the tolerances are. I do not have a micrometer, but my dial calipers all indicated that each of the original shims are the same thickness. I was limited by the precision of my measuring device, but all the shims measured out to be very close to 0.008" thick.

You are absolutely correct that the shims are cut to different shapes for different caps.

I have had no problems finding bearings. I already ordered them from SOR. What I have not found yet is a source of variable shim thicknesses. SOR offers a used bearing shim set, but there is no indication of thickness options. The engine FSM does not indicate any shim thickness variability, as indicated by the passage I clipped in the original post.

If you can tell me a different page in the FSM that indicates crankshaft main bearing shim thickness options, I would appreciate it.

By the way: the main bearings are different between the F135 and later F motors.

 

[MoCoNative]

I looked at my engine manual, and it also does not indicate shim thicknesses, here is an electronic page for the later F engine, (thanks to coolerman) http://www.globalsoftware-inc.com/c...39EngineInspectionRepair3-22FEngineManual.jpg

It just says to go back with the original shims. In a perfect world the shims should not change I guess. They would have been put in to make the journal round, and the outside diameter of the bearings should always be the same.

I guess try it, you may be just fine. I need to dig out what is left of my assortment to see how they are marked, but I'm prety sure they all had thicknesses imprinted on them.

 

[Heirloom]

I looked at my engine manual, and it also does not indicate shim thicknesses, here is an electronic page for the later F engine, (thanks to coolerman) http://www.globalsoftware-inc.com/c...39EngineInspectionRepair3-22FEngineManual.jpg

It just says to go back with the original shims. In a perfect world the shims should not change I guess. They would have been put in to make the journal round, and the outside diameter of the bearings should always be the same.

I guess try it, you may be just fine. I need to dig out what is left of my assortment to see how they are marked, but I'm prety sure they all had thicknesses imprinted on them.

Bearings are on their way. I will install and measure with Plasti-gauge to see how everything fits together. I am hoping for the best, since the machine shop told me everything is within spec.

When I was measuring the shims, I did not see any markings to indicate thickness.

As always, thanks for the reply. I will update this thread with me results. Be patient, because parts are scheduled to arrive while I am on vacation. I won't have any results for a couple of weeks.

 

[MudDauber]

Heirloom,

How did the installation go? I'm working on a 1970, with similar shimmed mains. Did you happen to use any RTV (Black/Gray) on the 1st or 4th main? Given the date of this post I'm guessing that you may not recall. I don't want oil leaks, but when I disassembled my engine I don't recall any RTV type material on my mains to prevent leaks.

Thanks,

MudDauber

 

[Heirloom]

I did not put any RTV between the shims and caps when I bolted everything together. I did put a tiny dab of sealer in the corners of the first and last cap (where they meet the block) to help the oil pan gasket seal, after the bottom end was assembled.

How'd it go? Well, everything went together within specification and turns smoothly. Because I am on restricted budget and not in a hurry, I still haven't started the engine. I'm hoping to start it this summer, after working through fuel line fabrication (nobody makes M15x1.5 compression fittings anymore) and other miscellaneous necessities before startingethe engine.

The build thread in my signature has more details about the engine assembly and how I measured everything. I plan on spending some time updating the thread next week, if I get a little free time.

 

[mo68fj40]

I am in the process of reassembling my F135 engine and need one replacement .008 shim. Does anyone have a recommended source?

I have looked on SOR and cannot find just the shims listed.

Thanks!

 

[timmyisinthewell]

These pics are from my microfiche set for the F engine, 03/69 to 01/75. Maybe your '66 engine would be similar. I don't see alot of choices on shim thickness as shown. The "T" under the description column indicates thickness in millimeters.

 

[MudDauber]

Timmy nailed it.

I think the item referenced as #9 at $or is what you are looking for, has some at $75. Give them a call.

FJ40, FJ45, FJ55, FJ60, FJ62, FJ80, FZJ80, UZJ100 Land Cruiser Crankshaft, Gear, Pulley, Rod and Piston Assembly, Rear Main Seal - Specter Off-Road

Toyota Land Cruiser parts since 1983. From the oldest FJ25 and to the newest Land Cruiser, Non USA or domestic 40 Series, 60 Series 80 Series or 100 Series, SOR has the largest selection of top quality new and used OEM and aftermarket Land Cruiser parts in stock in the world. Specializing in...

www.sor.com

 

[mo68fj40]

These pics are from my microfiche set for the F engine, 03/69 to 01/75. Maybe your '66 engine would be similar. I don't see alot of choices on shim thickness as shown. The "T" under the description column indicates thickness in millimeters.

View attachment 3878853

View attachment 3878857

Thank You!

 

[mo68fj40]

Timmy nailed it.

I think the item referenced as #9 at $or is what you are looking for, has some at $75. Give them a call.

FJ40, FJ45, FJ55, FJ60, FJ62, FJ80, FZJ80, UZJ100 Land Cruiser Crankshaft, Gear, Pulley, Rod and Piston Assembly, Rear Main Seal - Specter Off-Road

Toyota Land Cruiser parts since 1983. From the oldest FJ25 and to the newest Land Cruiser, Non USA or domestic 40 Series, 60 Series 80 Series or 100 Series, SOR has the largest selection of top quality new and used OEM and aftermarket Land Cruiser parts in stock in the world. Specializing in...

www.sor.com

View attachment 3878858

Thank you! I placed an order for these! I had hoped to find just one but this set is the only option I found.

 

[mo68fj40]

I appreciate the quick responses! I ended up ordering them from $OR.