Over Sized Big End Rod Bearing

[Montana]

Well Im dieing to start my new Powerline 12/1 but it looks like I might have to do some crank work.  I have been putting together my set up when I noticed something grainy in the sump and some very fine black something on the crank case side walls..  I have washed it out as best I can but now Im wandering if I should tear eveything apart.  I am fighting the urge to hurry up and finish and put oil in her.  I also thought I should check the Main bearing. What I found was some scratches in the bearing shells.  Not to deep I think, but did notice one scratch going around the inside near the crank shaft oil hole.  I checked the crank and sure enough there is a scratch in the crank.  I can feel it with my finger and definitely feel it with my finger nail.  Im not sure if I should pull the crank out and polish it or just put it back together and run it as is.  If I pull it Im going to need oversize bearings.  Any one with over size bearings?

Mike

[Quinnf]

Mike,

There are three reasons you must do a complete teardown, cleaning and reassembly.  Any one of these, alone, is sufficient to make the task necessary.  But you have three reasons to do it.

1.  You have a new Indian engine.

2.  You found casting sand in #1 above without even looking very hard for it.

3.  You plan to use #1 above off-grid (in other words, you need reliable power).

Don't fool yourself.  If you run that engine, you'll end up spending much more time and money on it than if you just suck it up, clear some space and get to it.


Quinn

[sailawayrb]

Quinn speaks words of wisdom and great sorrow will befall those who do not listen 

[Montana]

Yea I guess your right.  It's just killing me to see it set there and cant run it, Oh well. 

So, any one know where to get oversized bearings in the usa?

[oliver90owner]

Hi,

1) the bearings would be under-sized, not over-sized and

2) You probably will not need any. In the old days when white metal bearings were scraped to fit, anything better than 80% contact (tested with with engineers' blue) was acceptable.

You are probably referring to the 'Big End' bearing?  The 'Main Bearings' are the ones which locate the crankshaft in the crankcase.

Always rectify if possible, or at least limit the damage to what is already there.

Quinn speaks' words of wisdom' and has had first hand experience in these matters.  See his write up in Utterpower dot com.

Once you have done it you will be confident to rectify the other issues you might find, other than a sandpit inside the engine.

Regards, RAB

[xyzer]

Mike,

There are three reasons you must do a complete teardown, cleaning and reassembly.  Any one of these, alone, is sufficient to make the task necessary.  But you have three reasons to do it.

1.  You have a new Indian engine.

2.  You found casting sand in #1 above without even looking very hard for it.

3.  You plan to use #1 above off-grid (in other words, you need reliable power).

Don't fool yourself.  If you run that engine, you'll end up spending much more time and money on it than if you just suck it up, clear some space and get to it.


Quinn

2A Chuck rod bearings and install new ones. Polish the journal. Engines that have been test run in the sand box show scrathes from sand. You might clean them up but is it worh it?
Dave

[billswan]

Montana

Take the advise of the seasoned posters above and STRIP THAT ENGINE TO THE BARE BLOCK. My Omega was a sand and machine grit pit, don't think yours will be different! If you get it apart and turns out it isn't as bad as everyone says well to bad so sad at least you will know how it ticks inside. I was hoping to do the same as you just flush and wipe it out but now I am glad I took it ALL apart. I took the crank out of my 10/1 Omega it was lightly sanded by the test run not to bad. Took it to local auto machine shop they polished it in a crank grinder only cost me 13$. Ordered a new standard bearing from CMD and now have a great result on that end of the rod. Now on to the small end of the rod that end isn't so pretty under the bushing, back to the machine shop.

How many shims were in the rod on your 12/1 most likely you will be able to take some out to get the set up right. My 10/1 had 2- .008 inch shims on each side after machine work and new bearing it now sets up right with 1 -.006 inch shim on each side.

Billswan

[Montana]

Sorry about the mismatch of terms.  It was late and I was tired,  but u'all got the gest.

Yep I have started the tear down.  I got the fly wheels off.  Piece of cake thanks to Phill at CMD, the puller worked great.  Got the piston out, it had 2 shims on one side and 1 on the other side of the connecting rod.  Got the massive counter weights off the crank.  I have not pulled the cylinder block yet.  Still debating if I really need to do it.   The cylinder looks good as no signs of scratches, buy it looks like a mirror very little signs of honing.   I still have a lot more to remove before I finally get the crank out.  Right now Im looking at the timing gears, just want to make sure I get it back in the right place.

[Tom]

Definitely take the cylinder off and have it properly honed, otherwise your rings will never seat properly. Also check the protrusion of the liner above the head surface and when you put it all check the bump clearance. 

[Montana]

Ok got every thing pulled apart but now Im wandering what is going on with all the gaskets.  I pulled the cylinder block and found 4 sets of gaskets between it and the crank case.  I also found 4 sets of gaskets between the crank main TRB housing and the crank case.  Why all the gaskets?

[oliver90owner]

Why all the gaskets?

To get the proper clearances.  They may not have been correct anyway. It's Indian.

Regards, RAB

[billswan]

Montana

On the 10/1 Omega I am rebuilding the crank had .135 inch worth of gaskets between the 2 main bearing holders! That is how the endplay is set on the crank. When I reassembled the crank I ended up with .150 inch worth of gaskets adding up the stack from both sides, to get to the correct end play on the crank. The Indians put the engine together with .015 inch preload on the crank, too tight in my estimation. Be carefull of getting the correct stack on the timing gear side as moving the crank to close to the Idler will interfere with the gear tracking and cause the crank to hit the Idler pin!
 The gaskets between the block and the crankcase set the bump clearance. Search the words bump clearance and read!

Billswan

[Montana]

OMG! U got to be kidding me. They used paper for shims?  The metal between the connecting rod I can understand but paper.  Looks like a long winter.

[Mucke]

OMG! U got to be kidding me. They used paper for shims?  The metal between the connecting rod I can understand but paper.  Looks like a long winter.

Nothing wrong with paper as long as it is on a large surface area and thus not highly pressed. Will work fine !
make shure you put it in without any plies for water tightness.
Some elastic joint cement will help.
Rolf

[billswan]

Montana

Yes paper is fine I even made up  one out of .003 inch typing paper and I'm not the least bit worried. When I assembled my 10/1 I sprayed each side of each piece of paper with light oil to make them not stick to anything and so they would compress. NOt sure if it will cause a leak without sealer but sealer may through off the compression of the stack and will make the gaskets junk if I find I made a mistake and have to disassemble the motor in a few weeks. Sealer of a thin fluid type would be ok if you are absolutely positive of your ability to get it right the first time and you are looking for a leak free result. But a leak free oid may be a reach if it is for work not show!

Billswan