Merc 2005 115HP Rod and Main Bearing availability

[pbob42]

Okay - serious rod knock.

Had a hole in my exhaust jacket. Water in my oil. Messed up #1 connecting rod journal bearing.

Machine shop says the crank is good and to just put in "standard" bearings, but I can't just replace the #1 inner and outer rod bearing. I need to do the whole set, and when I do the rod bearing set, I also need to do the main mearing set.

My rod bearings are green. Can't see any colors on my main bearings. Merc dealer only has yellow rod bearings. Blue inner main bearings, blue or yellow outer main bearings so I can't find Green rod bearings and don't know what color my main bearings should be.

Mismatched (from my original) bearing sets look to be $250

Love to get some input.

 

[boscoe99]

What is your Mercury service manual telling you to do with respect to bearing selections?

 

[pbob42]

Match what is there. Struggling with availability. I'm not seeing any colors on the main bearings

 

[pbob42]

Says to verify tolerances with plastigauge

 

[boscoe99]

Is the serial number of the motor not known?

 

[boscoe99]

Says to verify tolerances with plastigauge

Nothing in there about bearing color selection?

 

[pbob42]

There is a table that gives difference clearances for different colored journal bearings. So, as I read it, because I have green journal bearings, I need green clearances (as listed in the table). If I am out of tolerance, it does not say to change colors, it says to get a new crank.

 

[pbob42]

I am seeing some WSM green bearings on ebay. What do you think about just replacing the #1 rod bearing, checking all the tolerances and going for it?

 

[boscoe99]

What is the serial number of your motor? I am thinking that it is made by Yamaha but maybe not.

 

[pbob42]

yes, made by yamaha that year. 1115F23DY

 

[boscoe99]

yes, made by yamaha that year. 1115F23DY

That does not look like the serial number.

 

[boscoe99]

A Yamaha crankshaft and the block should have some markings stamped on them. Those markings are used to get to the correct bearing colours. Yellow, red, green and blue. Then using plastigage a check is performed to assure the proper clearance.

Same with the rod bearings.

 

[pbob42]

1B200265

 

[pbob42]

seeing there is stamping on the crank and case to tell what bearings are to be used.

Can I get by with changing the damaged bearings or do I have to do them all?

 

[boscoe99]

Comparing images in the Mercury parts catalog with images in the Yamaha parts catalogs shows them to be identical.

Below is an image from the Yamaha service manual. See if your crankshaft and your cylinder block have the markings which are used to get to bearing colours.

If your bearings are not worn, and the clearances are within specification, some would argue for their reuse.

 

[pbob42]

got the markings on the crank. Ordered the appropriate center main bearings and the #1 rod bearings. Got it all together and is spinning like a top. Going to mount it next week. Thanks for the guidance