'72 800 crankshaft bearing interchangeable part??

[KT64TM]

okay, finally found the root of all my engine problems. My top crank bearing is SHOT to HELL along with it went the oil seal. Got that today.

My question is:

Is there a cheaper alternative to the Mercury part? Like a timken from autozone?? anything?

Your help is much appreciated.

 

[Bifflefan]

Re: '72 800 crankshaft bearing interchangeable part??

Id use the Merc part. the specs on tolorance will be better than any other and you only want to do this once,,right???

 

[KT64TM]

Re: '72 800 crankshaft bearing interchangeable part??

Id use the Merc part. the specs on tolorance will be better than any other and you only want to do this once,,right???

what do you think about sierra?

 

[Faztbullet]

Re: '72 800 crankshaft bearing interchangeable part??

Serria,Pro-Marine,Redline all sell the same bearing re-packaged as it a NTN 6206W. I would check #1 & #2 cylinders real good as when the cage fails its debris usually ends up in these 2 cylinders.

 

[KT64TM]

Re: '72 800 crankshaft bearing interchangeable part??

Will do. I have access to a borescope.

 

[Moody Blue]

Re: '72 800 crankshaft bearing interchangeable part??

Chances are that if you take a careful look at that bearing you will find a number stamped into the face of it. You should be able to take that bearing number to any bearing supply house and get an exact replacement. Mercury did not make their own bearings, they bought/buy an off-the-shelf bearings just like everyone else.

Curious, what does the bearing look like? Is it coming apart or corroded or ???

 

[KT64TM]

Re: '72 800 crankshaft bearing interchangeable part??

Btw. How do I go about removing the housing up there? Don't have a plate puller

 

[KT64TM]

Re: '72 800 crankshaft bearing interchangeable part??

Coming apart. A few of the balls are chewed. I attatched images to the first post.

 

[Faztbullet]

Re: '72 800 crankshaft bearing interchangeable part??

You are going to have to remove and split powerhead to change this out as bearing is pressed onto crank. You will get a good look at internals and since your there replace lower bearing also.

 

[KT64TM]

Re: '72 800 crankshaft bearing interchangeable part??

Sonuva.............

 

[KT64TM]

Re: '72 800 crankshaft bearing interchangeable part??

There is no play in the crnkshaft end.

 

[emckelvy]

Re: '72 800 crankshaft bearing interchangeable part??

The top bearing is Not a "6206". It's a "5206" which is wider than the lower crankshaft bearing which Is a "6206".

You should be able to go to your local bearing house and pick one up, even your local auto parts store should be able to order one. And if you end up with a shielded bearing, just pry the shield(s) out and you're good to go.

I have a similar issue with a noisy top bearing on a '73 850 and you'd have to have a Very Very thin-jawed puller to get the bearing out without splitting the cases.

Something like this maybe could work, but it sure would be a Bummer to order one and find out it doesn't fit:

http://toolsandmore.us/neiko02255abearingpuller.aspx

The top bearing/seal end cap does pull out without too much trouble, but it's quite tight in there.

With the cases split you'll likely need to use a split-type bearing separator to get the bearing off the crankshaft. There's very little clearance between the crankshaft counterweight and the bottom of the bearing, in which to get the jaws of a bearing puller.

Something similar to this should do the trick:

http://cgi.ebay.com/ebaymotors/14-P...Z120472734057QQptZMotorsQ5fAutomotiveQ5fTools

HTH & G'luck..........ed

 

[KT64TM]

Re: '72 800 crankshaft bearing interchangeable part??

Wow thanks! I've been considering just replacing the oil seal and being gentle with it. I don't plan on keeping this old boat for too long before upgrading.

 

[KT64TM]

Re: '72 800 crankshaft bearing interchangeable part??

Purrs like a kitten now

 

[ss von scalliwag]

Re: '72 800 crankshaft bearing interchangeable part??

Hi there,
I'm just about to undertake exactly the same job on exactly the same engine. Has any one got any useful tips or advice on how to get the bearings on and off without to many problems?!.
Many thanks in advance