Spun the rod bearing, CRANKSHAFT is FUBAR

[Hugh Conway]

Not fun when off-grid in mid-winter Canada.

Time on engine: about 3500 hours. It's operated well until this suddenly happened.

Found the culprit.......the old bugaboo of casting sand under the head of the piston. A chunk let go........
When new, I tore the whole thing down, cleaned the sand out of the crevices, did a pretty good job of cleaning up the crankcase, but never looked under the piston.

Looks like a chunk recently broke free and went right to the rod bearing with the expected result.


Just pulled the engine down, the crankshaft is hooped beyond any easy repair.
Looks like the bearing seized on the crank, then spun in the rod, then came loose tore up the crank journal some more, this probably happened a few times, looking at the damage.

Of course, I have all the spares on hand EXCEPT a new crank.

My immediate issue is removing the old one.
Tomorrow I will try removing the TRB carriers, then the shaft.
What should I look out for during removal?

Then the replacement: How are the new TRBs installed on the crank?

Once the  new crank has the new bearings installed, and are properly in place, I know how to shim up the carriers, and have shims, just don't have any experience with installing the TRBs on the shaft.

Any advice welcomed.....please!.....

Cheers
Hugh

[Powdermonkey]

Forgive me, Hugh.  What is a TRB?  It's a bit late in the evening....and nothings coming to mind.

[broncodriver99]

What is a TRB?

Tapered roller bearing.

[broncodriver99]

Ouch, sorry to hear that Hugh. For reassembly if you don't have a press available I would recommend just putting the crankshaft outside for a few hours since you are up in Canada. Ideally get the crank below 0 F. I would heat the bearings to about 200-250 F and be ready with a piece of pipe that will slip over the end of the crank and a hammer. The thermal expansion/contraction should be enough that the bearings should pretty close to slide on but have the pipe and hammer at the ready just in case.

[Hugh Conway]

Good evening Powder
TRB = Tapered Roller Bearings.
The real Dursley Listers used sleeve bearings on the crankshaft mains.
The Indian manufacturers redesign replaced them with TRBs.
I have not removed or installed them before so any tips are appreciated.
Cheers
Hugh

[BruceM]

Oh boy, that sucks, Hugh.  Couldn't be worse timing for such a major repair. I hate working in the cold.

Oven heated bearings on chilled crankshaft sounds good to me.  Seal the oiled crankshaft in a trash bag and sit it out overnight.  I wish you a smooth restoration effort and warm hands.

I guess I was lucky to have only wrecked half a dozen sets of journal bearings before I finally found the sand and grease sabotage under my piston crown.  What I worry about is sand pockets behind putty and paint in the crackcase...which might take years and years before finally letting go.  For my neighbors DES 8/1 (converted to spark-propane), I took no chances and had the very rough cranckcase ground smooth with a big carbide burr, and sealed with red electrical varnish per 38AC's recommendation.   

Bruce

[cujet]

As a general rule, any forged crankshaft can be safely welded up and re-machined. It really is not a difficult process, and when done correctly, is 100% trouble free.

Ohio crankshaft can probably do it.

Also, undersized bearings can often save a worn crank. What typically looks horrible is often not as deep as it seems. Also, even if there is a groove or two, after being re-machined, it will typically hold up fine.

https://ohiocrank.com/save-the-crank/

[38ac]

Typically the bearings are a light press fit. I heat them in a pan of oil and drop them on.  I guess you already have a new crank? I have undersized bearings to .030" or 040" in stock if that helps and you have a place to get it ground but shipping across the border has been terribke slow as of late.

[Hugh Conway]

Thank you all for the suggestions.
I have found a new crankshaft. Jim Calder of justliveoffgrid.com has a pretty good stock of parts. He is in Ontario. It's a long way to the west coast, and shipping is costly. It's a lot more expensive to source from out of country, say U.S. U.K. or India. They sock you with all sorts of brokerage fees, duties, and taxes in addition to the shipping costs.
Cujet' s suggestion re Ohio crank may be a way to rescue a damaged crank, the the two-way cross border shipping to the other side of the continent would be pricey.
There is a good machine shop available on Vancouver Island, but even that is a day's travel to get there.
I will eventually take some photos of the damaged parts. I would bet that the crank is not economically repairable.....it's not scratched, it is heavily and deeply gouged. The bearing seized on the crank then broke loose. it even did that after taking off the head and rotating the the crank. the inner surface of the rod is even a bit scored, though that is probably reusable. I am fitting everything new though. Crank, TRBs, piston & rings, cylinder, etc.
I am waiting for temperatures to warm up closer to freezing before doing any more tear down. It's been -17*C here the last few days. Hard on the fingers.
Cheers
Hugh

[cujet]

I'll bet there are more local machine shops who can fix that crank for you. Keep it as a spare. Clean it up and measure. I've seen many "destroyed" crank journals clean right up with sufficient undersize. In fact, even my aircraft engine's crankshaft that had a camshaft destroy itself and put hardened metal bits throughout the oil, cleaned right up. It looked utterly destroyed. 18 years down the road, after under sizing the journals, it's working fine.

Remember, a spark plug gap is often 0.032, so the above mentioned 0.040 undersized bearing would be a lot of metal removal.

[dieselspanner]

Hi All
I can't remember who, but someone on here put up a thread where he sorted out the crankshaft and then made his own bearings from a piece of aluminium plate......

Cheers
Stefd

[keith71]

Hugh said   

"He is in Ontario. It's a long way to the west coast, and shipping is costly. It's a lot more expensive to source from out of country, say U.S. U.K. or India. They sock you with all sorts of brokerage fees"

DEV on ebay has a trb or bushed 6/1 crankshaft for around $265 shipped to U.S. And I believe they ship to canada with shipping included as well.. They can also supply the bearings in the oversize you need if you machine your crankshaft.
 Or can you find a shop near you that will grind the rod big end?  38 AC has bearings for a crankshaft that has been ground..  Would you need more than .020-.040 removed?  I will see if I can post a link if you need.  Good luck on your project.

[dieselspanner]

Hi All

After a good nights kip it came to me, the home made ally bearing was 'Starfire'

https://listerengine.com/smf/index.php?topic=9316.msg107165#msg107165

Worth a look......

Cheers
Stef

[ajaffa1]

Hi Stef, Starfire came up with a very inventive way of doing emergency repairs using just hand tools and what was available locally. Hugh is probably looking for a more permanent and long lasting repair. I wonder what Starfire would have done about the damaged taper roller bearings.
I recently had to replace a pair of TRBs in a Cooper vintage engine, replacements were only available in the UK at nearly 500 pounds each. I machined the casings to take much more modern TRBs at a fraction of the cost.

I don`t envy Hugh trying to do this sort of work in the subzero temperatures where he lives.
Good Luck.

Bob

[Hugh Conway]

Today I lifted the crankcase  and lower end off the engine mounting and relocated it to a more convenient place so the flywheels could be removed.
Gibb keys were easily withdrawn. The wheels seem welded to the crank.........crap!
A very large gear puller brought no joy. Same with a heavy sleeve over the shaft and a 10 lb sledge.
Heating and repeating with sledge same result. Soaked it all in ATF/solvent. Will try again tomorrow.
If I can get them to move at all, I will get them off.

I suppose worst case is to cut off the shaft between the TRB carriers and the wheels. A bit drastic, but maybe last resort. I will work on it a lot more before going that route!

At least the weather is warming up.......it got warm enough to snow, so it did.

Cheers
Hugh