Crankshaft Journal Wear

[Blakek25]

Hello, I was putting my 1998 Johnson 225 powerhead back together and noticed some wear around the crankshaft journal of the #2 cylinder. This is circled in the attached picture. #2 was the cylinder that went out. The piston ring locator pin came out.

What would cause this wear? Was something not put together properly last time? Was there a lack of lubrication and fuel that caused the wear and also caused the cylinder to run lean and hot which caused the piston ring locator pin to come out?

Also, will this cause any issues when the motor is rebuilt?

Thanks!

 

[jimmbo]

Since each cylinder has its own carb throat(fuel bowl shared by two cylinders), on carb leaning out can cause overheating of the piston and lack of Lubrication to the bearings.
I know someone might disagree, but I say the crank can't be trusted. A journal has gotten hotter than intended, and its Surface Hardening may have been weakened. What condition is the Connecting Rod? Bearing will need to be replaced

 

[racerone]

A 1998 model 225 would have 6 plastic carburetors with a single bore to feed one cylinder.------But I agree that crankshaft and the rod should be replaced.-----And I think there are lots of good used ones that can be found.

 

[Blakek25]

It's not a great picture, but the damage isn't on the journal itself, it is on the side of the journal, from the side of the connecting rod rubbing on the crankshaft. Where the C shaped outline is in the picture on this post. The journal itself is still in good shape and doesn't show any abnormal signs of wear.

I'm not sure what is supposed to keep the connecting rod from rubbing on the crankshaft. Is it just supposed to be oiled enough that it won't cause damage?

I am definatley replacing the connecting rod, and probably the crankshaft if you all think it should be, but I just want to make sure there isn't something special that needs to be done to prevent this again, other than making sure it gets adequate fuel and oil.

 

[racerone]

I have seen that kind of damage before.----Measure / compare the journals with some quality measuring tools.

 

[Faztbullet]

Crank needs replaced along with rod and all pistons besides the one that failed. This is a cooling issue with block that causes locating pin to migrate out. If one has failed the other are loose and will soon follow. Need cooling mod installed to block.. View attachment MarFab_Tech_Bulletins_D9579.pdf

 

[jimmbo]

A 1998 model 225 would have 6 plastic carburetors with a single bore to feed one cylinder.------But I agree that crankshaft and the rod should be replaced.-----And I think there are lots of good used ones that can be found.

Thanks for the correction Racer, I was thinking Crossflow, I should have caught the 225