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B&S Engine Loose crankshaft


jl66redcpe's Avatar
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NJ

08-30-08, 08:00 AM   #1  
B&S Engine Loose crankshaft

I picked up a 2 yr old Poulan Lawn Mower off of ebay this week. It has a B&S 123K02 6.5 HP engine on it. The previous owner said it just stoppped running. I figured it was a kill wire or the crankshaft key. This thing looks brand new. I took the mower home and checked the oil. It was bone dry. To make a long story short, the crankshaft is wobbling (loose). I can rock it from where the flywheel mounts. Before I tear into this where would be a good place to look to first. Obviously there are bearing problems somewhere and perhaps other downstream damage. Is it worth fixing ? I think I can do the work. I just need some places to check.

 
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08-30-08, 11:18 AM   #2  
If you can move the shaft in the engine, then there is likely damage to the top and bottom bearing surfaces in the engine block and oil sump. It's likely not a cost effective repair, but if you want to take a look, I would remove the crankshaft and inspect the upper, lower and crankpin journals on the crankshaft and the machined bearings in the block and sump.

Let us know what you find, and if you have any further questions, just ask.

Good Luck....

 
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08-30-08, 01:10 PM   #3  
Worst case is that they never put oil in it before the first use. That would explain the extreme wear on what appears to be a new engine/mower.

I looked at the listing on ebay. Maybe the power washing made it look so good. At $15.50, it looks like a fairly cheap lesson, though.

 
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08-30-08, 05:50 PM   #4  
Posted By: rogerflies Worst case is that they never put oil in it before the first use. That would explain the extreme wear on what appears to be a new engine/mower.

I looked at the listing on ebay. Maybe the power washing made it look so good. At $15.50, it looks like a fairly cheap lesson, though.
Rogerfiles - I made sure they DID NOT powerwash it before I picked it up. The unit really is that nice. God they would have blown carb and gov springs all over the place not to mention water forced into everything. I actually have a spare 123K02 engine sitting on the garage floor. If I could not fix the one on the Poulan, I was going to swap parts. The one on the floor runs perfectly. I just hate to scrap an engine this new.

 
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08-31-08, 01:27 AM   #5  
Yeah, I know what you mean. I picked up a new mower with a bent crank at the dump in 1968. I cut the crank off at the bottom of the bottom bearing, and sealed up the hole, added a pulley from the water pump of a '56 chevy, a 1/3HP motor from a discarded washing machine, and a pressure switch from a discarded pump. I made a new cylinder head with a check valve (freebie from a salesman), and played around with the valves and springs.

I ended up with a pretty indecent air compressor which I've been using since:


I saved the original oil that was in the engine, and put it back in. It's still there. It's only forty years old. I did put on a new hose ($2 at a yard sale) a couple years back.

 
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08-31-08, 01:38 AM   #6  
Well now that's a pretty neat tire-pumper-upper! Good job on it!


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

God bless!

 
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08-31-08, 04:37 AM   #7  
That is a great air compressor !!! I really enjoyed the story - thanks. I guess there are still a few of us left

 
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