FJ1346 from ashes to... Well, we'll see...

[movenon]

It looks like the rear brg of a small block chevy,  somebody is being funny.

Thats what it looks like to me, too.

   Joe

Yep....
George

[JMR]

It looks like the rear brg of a small block chevy,  somebody is being funny.

Thats what it looks like to me, too.

   Joe

Maybe the end bearing from an XS1100....I never worked on one of those freaking tanks thank God!

[skymasteres]

Maybe the end bearing from an XS1100....I never worked on one of those freaking tanks thank God!

You know you hit it right on the head. It was a Yamaha XS1100-FJ1​200 Crank Bearing kit that I got.
Now here is the interesting part. If I put the bearing on an upper web it fits just fine, and there
seems to be plenty of clearance between the crackshaft webs. So I don't think the thrust potion of
the bearing is really going to do anything. (Or if it does actually make contact then something else
has gone dreadfully wrong...)

[SlowOldGuy]

So, if not this bearing, then what takes up the thrust loads on the crank?

Something has got to keep the crank from walking around, right?

DavidR.

[skymasteres]

So, if not this bearing, then what takes up the thrust loads on the crank?

Something has got to keep the crank from walking around, right?

DavidR.

You know, you're right. Just because the thing seems to line right up now doesn't
mean it's not going to dance all around once it's togeter and the engine is spinning.

When I get home I'm going to recheck all of the widths of the crank journals.
See if one is the right size for this bearing.

[skymasteres]

Well, bearing questions aside, I am itching to make more progress on this thing. I have been putting off
doing the coatings on the cylinder head. I finally bit the bullet and threw the sucker into the blast cabinet.





Combustion chambers masked



These oil passages were one of my excuses for not getting this done sooner.
Needed to go get plugs. Interesting note, I don't think they're 1/8" NPT threads...



Putting it though the high pressure grit application process...



Here is the head and valve cover all cleaned up and ready for coating.



Of course with the appropriate ports all masked.



What I am doing on this piece that makes it more of a challenge is applying four different coatings
at once before it is cured. There is the thermal dispersant that is going on the valve cover and fins,
the dry film lubricant going on the intake runners, the thermal barrier going on the exhaust ports
and the ceramic lubricant for the camshaft bearing journals...

An intermediate step...



Drying. Waiting for it to be hard enough to handle. Part of the challenge is making sure that you
don't contaminate any of the cleaned surfaces before you get them coated.



Hear the cam journals are ready to be coated.



Chambers masked again for the thermal dispersant.





Here is the finished part on the oven for curing. (The leftover coating in the chambers will rub
off when I burnish the thermal barrier that's already on them.)

[skymasteres]

I have never seen one of those in an FJ engine. First thing I would check is if the bearing fits between any of the crank shaft main bearing journals? If it does not fit it is definitely for a different application.

Was that something that was supplied to you to machine down the thrust bearing surface of the case as a replacement to the stock bearing using the case as the thrust? I ask because the thrust is only controlled at the upper portion of the case.

Randy - RPM

Okay, now I understand what you mean by the upper case controls the thrust. That's why there
is so much clearence with this thing. The upper crankcase webs are totally keeping the crank positioned.

It doesn't seem like the  extra flange on the bearing is going to hurt anything.
(It certainly doesn't help anything either) So I'm just going to leave it where it is. (It fits the crank fine)

[racerrad8]

It doesn't seem like the  extra flange on the bearing is going to hurt anything.
(It certainly doesn't help anything either) So I'm just going to leave it where it is. (It fits the crank fine)

It might not seem like it, but there is something to consider...

If you use that bearing instead of the proper bearing, you now have two thrust surfaces attempting to hold the crank. The incorrect bearing will not have anything to help it control the thrust other than the small positioning key/groove. If the incorrect bearing is side loaded and damages that key on the bearing or the groove in the case allowing the bearing to come loose, you will have a loose bearing and an issue.

There should never be any more than one thrust surface in an engine.

I understand you cannot return the bearing because you coated it, but why after all of the work and money you have and are spending on the engine not install the correct bearing when the correct bearing costs $9.56.

I would hate to see all of this work and money down the drain when it spins a main bearing and you have to start over again.

Randy - RPM

[skymasteres]

It might not seem like it, but there is something to consider...

If you use that bearing instead of the proper bearing, you now have two thrust surfaces attempting to hold the crank. The incorrect bearing will not have anything to help it control the thrust other than the small positioning key/groove. If the incorrect bearing is side loaded and damages that key on the bearing or the groove in the case allowing the bearing to come loose, you will have a loose bearing and an issue.

There should never be any more than one thrust surface in an engine.

I understand you cannot return the bearing because you coated it, but why after all of the work and money you have and are spending on the engine not install the correct bearing when the correct bearing costs $9.56.

I would hate to see all of this work and money down the drain when it spins a main bearing and you have to start over again.

Randy - RPM

I appreciate the comment Randy. I'll check it out tonight and check to see exactly how much clearance I have there.
If it's huge like 0.15" I think I'll just leave it. (I mean, if the crank moves that much laterally just to make contact I'm
probably hosed anyway) What's the max play allowed in the crank side to side anyway?

[racerrad8]

Since the upper case is the trust and there is no "adjustment" there is not a Yamaha specification. It truly is based on the condition of the upper case thrust surfaces.

It has been so long since I checked one I cannot recall the measurement I took.

Randy - RPM

[HARTLESS]

It doesn't seem like the  extra flange on the bearing is going to hurt anything.
(It certainly doesn't help anything either) So I'm just going to leave it where it is. (It fits the crank fine)

It might not seem like it, but there is something to consider...

If you use that bearing instead of the proper bearing, you now have two thrust surfaces attempting to hold the crank. The incorrect bearing will not have anything to help it control the thrust other than the small positioning key/groove. If the incorrect bearing is side loaded and damages that key on the bearing or the groove in the case allowing the bearing to come loose, you will have a loose bearing and an issue.

There should never be any more than one thrust surface in an engine.

I understand you cannot return the bearing because you coated it, but why after all of the work and money you have and are spending on the engine not install the correct bearing when the correct bearing costs $9.56.

I would hate to see all of this work and money down the drain when it spins a main bearing and you have to start over again.

Randy - RPM

I'd have to second that( not that anyone asked my opinion...) but the extra ten bucks is
Nothing compared to the thousands
You have already put in.... Just mho

[skymasteres]

Since the upper case is the trust and there is no "adjustment: there is not a specification. It truly is based on the condition of the upper case thrust surfaces.

It has been so long since I checked one I cannot recall the measurement I took.

Randy - RPM

Okay, thanks Randy. I'll more fully investigate it. But would you consider my hypothesis correct on the level
of clearance available for the odd bearing? I mean, yes, contact would be bad and that little locating tab
wouldn't stand up to any real side loads. BUT, if it can't make contact, it can't make contact... So, if the
clearance is tight with the upper web then, the flanges just hang out in space fat dumb, and happy, never
to be molested by the crankshaft.

(And I learned my lesson on the o-ring thing. Bought the Yamaha o-rings, and they were identical in every
measureable way to the ones I sourced from the hardware store.) They may be slightly different chemically,
so I am glad I bought them, but I am sure I would have been fine with what I found.  Now that doesn't
include some of the little o-rings I bought for the rotating parts, those I fully support going with the OEM.
(Of course they are really odd, hard to find sizes anyway)

On another note, I am still running around looking for parts. I mean, this thing has been apart for over a year,
stripped down to just about its assembly line components, all sitting in plastic baggies, and just waiting to
get lost. I mean, I have plastic baggies all over and I still can't find things...

Like these little clamps for the engine.

[skymasteres]

I'd have to second that( not that anyone asked my opinion...) but the extra ten bucks is
Nothing compared to the thousands
You have already put in.... Just mho

And all opinions are welcome. I appreciate the feedback that you guys give me on this project.
I am going to verify the cleareance and see if it is even possible for this to be an issue. If it is
you can rest assured that I will go out and get an additional bearing. If it isn't I will seal the
sucker up and not worry about it. Secure in the knowledge that while I still may ultimately hose
myslelf on this project, it won't be because of that bearing.

[HARTLESS]

I'd have to second that( not that anyone asked my opinion...) but the extra ten bucks is
Nothing compared to the thousands
You have already put in.... Just mho

[skymasteres]

I'm not quite sure what you're trying to accomplish HARTLESS, other than emphasise your comment.
But I will get to the bottom of that issure. (And yes, the $10 is a drop in the bucket on this one)