Conn rod bearing is shot

y2kbaja · Sep 12, 2013

I just had the top end done by BDT and it's beautiful. Now I noted the connecting rod bearing has nearly 1/8" of vertical play. Question is what do I need to replace? Should I get a crank/rod assembly? Crank/rod assembly with main bearings? I have yet to split the cases but it was all running well when it came apart (top end seized) so I assume the lower end is ok except for the conn/rod bearing.
This is on my stock 1988 250R, original owner, cases were split once about 20 years ago to replace a broken transmission.

The Phantom · Sep 12, 2013

If its oem stock crank have it rebuilt and get new crank bearings/seals. Oem is the way to go if the tins are good.

american opel · Sep 12, 2013

^^^agree.sorry to hear about the rod.

brett 250r · Sep 12, 2013

I would have crank rebult before u put a fresh boar on

y2kbaja · Sep 12, 2013

Thanks for the replies. I will call Carlos and see what he wants sent to him to rebuild the crank. Unfortunately I blew most my wad on the full ground up quad restore so this will have to wait a bit.

acecarlos · Sep 12, 2013

Wow 1/8" vertical play....take some pics and post them or give us a call. Here to help....

Carlos

y2kbaja · Sep 13, 2013

Hard to see in the pictures but there is definitely a measurable difference.

jd267 · Sep 13, 2013

what is the pic showing? you measuring something?

american opel · Sep 13, 2013

if you look at the side on the rod end you can see the difference.atleast i can.

y2kbaja · Sep 13, 2013

american opel said:
if you look at the side on the rod end you can see the difference.atleast i can.

That's what I was trying to show. I couldn't figure out how to take a picture with a caliper measuring the difference.

acecarlos · Sep 13, 2013

Side to side play is the least of the wear indicators to be concerned about. Up and down rod play, and rod tilt are the the real wear indicators to keep an eye on. How does the Rod feel when you pull and push up and down owhilenholding the Rod at TDC?

How about Rod tilt? Holding the Rod at TDC and in the middle of the crank firmly, does the Rod tilt Left or Right more tha a few degrees?

Carlos

y2kbaja · Sep 13, 2013

Side to side isn't much which is why I thought the lower end was good. Up and down is excessive at nearly 1/8".

Is it still better to have the OEM rebuilt or buy a new Hot Rod? I also remembered that I boogered the threads on the crank while trying to get the flywheel off when the stator took a crap. I was able to file and retap the threads but I know it won't pass a thorough inspection the way it is. Plus if a new crank/rod is in stock with new main bearings I'm riding sooner.

Conn rod bearing is shot

y2kbaja

The Phantom

american opel

brett 250r

y2kbaja

acecarlos

y2kbaja

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