FJ180 scored crankshaft and top bearing

Cfs

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I am working on a John Deere JX75 a 21 inch self propelled mower approx 25 yrs old it has a Kawasaki FJ180V-AS11 engine. The connecting rod broke. When I opened up the engine I found the cylinder and piston and rings to be in great shape. The connecting rod journal on the crank looks good no damage there. There is however scoring on the crank at the upper bearing where it passes through the lid/top of the engine. The bearing is not replaceable it’s part of the aluminum lid. The complete lid is no longer available. What I can use help with is this: is there any way to dress/clean up the scoring on the crank and the scoring on the bearing surface. Anybody had any success stories to share? I was thinking that I could attempt to sand the crank with emery cloth and clean up the scoring on the crank. Not as sure what I could do with the lid
Any ideas welcome
Spit
 

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sgkent

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muriatic acid then neutralized will eat aluminum off the journal then lightly sand it, but a hogged out bearing race is a different story. Wrap the journal with some cloth and tie it. Soak the cloth in muriatic acid and let it sit about 20 - 30 minutes, keep an eye on it and wear protective gloves. neutralize it in water with a little baking soda in it, then rinse it well. Immediately dry well and then coat with wd40. Polish with some 1500 grit or so of wet and dry using a piece wrapped around it with a piece of rope with several winds on it. Use a good machinist's / babbitt scraper to scrape the bearing journal and see if you can clean it up. If you use sand paper you may embed grit in the aluminum if you are not extra careful. Best guess is that if you take measurements using a micrometer, inside and outside, the engine will be a used engine still but it may run and service you for a few more years. It is 25 years old. Maybe a used engine from a mower bone yard may be a solution too.

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Auto Doc's

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I am working on a John Deere JX75 a 21 inch self propelled mower approx 25 yrs old it has a Kawasaki FJ180V-AS11 engine. The connecting rod broke. When I opened up the engine I found the cylinder and piston and rings to be in great shape. The connecting rod journal on the crank looks good no damage there. There is however scoring on the crank at the upper bearing where it passes through the lid/top of the engine. The bearing is not replaceable it’s part of the aluminum lid. The complete lid is no longer available. What I can use help with is this: is there any way to dress/clean up the scoring on the crank and the scoring on the bearing surface. Anybody had any success stories to share? I was thinking that I could attempt to sand the crank with emery cloth and clean up the scoring on the crank. Not as sure what I could do with the lid
Any ideas welcome
Spit
This poor thing has lived a long life. Sorry, it's time to let it go or find a better engine. There is no "polishing" that will save the crank journal and bearing surfaces. All that does it take metal away and increase the oil clearances. After that, the connecting rod will likely break and take everything inside apart with it.
 

StarTech

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This poor thing has lived a long life. Sorry, it's time to let it go or find a better engine. There is no "polishing" that will save the crank journal and bearing surfaces. All that does it take metal away and increase the oil clearances. After that, the connecting rod will likely break and take everything inside apart with it.
It all depends the journal condition after the Muriatic Acid bath. And have everyone forget about installing sleeve bearings? Yes it take some research to find the right one.

Few important things about Muriatic Acid. Don't use it indoors. When using outdoor make sure to have good airflow as it will take your breathe away. Highly toxic at full strength. And after cleaning and neutralization the metal parts must oil immediately or they will flash rust. Also don't have anything in the area you don't want damaged as fumes is heavier than air most time and will settle in the area and cause steel to flash rust.
 
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txmowman

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I am working on a John Deere JX75 a 21 inch self propelled mower approx 25 yrs old it has a Kawasaki FJ180V-AS11 engine. The connecting rod broke. When I opened up the engine I found the cylinder and piston and rings to be in great shape. The connecting rod journal on the crank looks good no damage there. There is however scoring on the crank at the upper bearing where it passes through the lid/top of the engine. The bearing is not replaceable it’s part of the aluminum lid. The complete lid is no longer available. What I can use help with is this: is there any way to dress/clean up the scoring on the crank and the scoring on the bearing surface. Anybody had any success stories to share? I was thinking that I could attempt to sand the crank with emery cloth and clean up the scoring on the crank. Not as sure what I could do with the lid
Any ideas welcome
Spit
The part number for the crankcase cover is 14041-7009, still available from Kawasaki. See your local Kawasaki Engine dealer. If it is not exclusive to Deere, they should be able to order. This engine was built in 2004.
 

sgkent

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Cool - from $30 good used on ebay to $86 from KW. I saw the price on a crank this morning about $50 so that is a bargain on a 20 year old engine. Be sure to measure the crank journals and rod big end (at least for wear) before ordering a crank to be sure it is STD and that the rod is not too worn.
 

Cfs

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Thanks to everyone for your input. This is one heck of a mower with a cast aluminum deck and is in great condition.

The concern that I have with the crankshaft is scoring not on the rod journal but at the top of the crank where it passes through the lid. Of course the lid bearing is just a machined surface in the aluminum lid and not a ball bearing.
I have seen this kind of damage in a Honda and a Briggs before. It is amazing to me, that the aluminum bearing surface is able to cause scoring on the steel crank but it does happen.
I have not pulled the crank out of the bucket and have not seen the comparable bearing surface or crankshaft condition at the lower bearing.
Anybody have a prediction on the condition of the lower bearing mating surfaces? I would assume that the lower would be less likely to be damaged since it is immersed in oil at the bottom of the crankcase, while the upper depends on oil being pumped up to lubricate the surfaces.

CFS
 

Auto Doc's

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Pictures of your concerns would help us help you.
 

Cfs

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Pictures of your concerns would help us help you.
I will do that later this afternoon. I put the engine back together so I would be able to remember how every thing went together. When I was posting the photos off the shattered connecting rod I was kicking myself for not taking photos of the lid and crankshaft
 
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