Joined: Jan 15, 2012 Posts: 851 Location: Lawton, Michigan
Posted: Tue Jun 27, 2017 9:03 am Post subject: RD350 outer crankshaft seal replacement
Looks like I might have a bad right outer crank seal. Not having done this before; can I get the seal out without splitting the case? I'm almost sure they are the original seals (1974). Thanks _________________ -Ray
Joined: Oct 30, 2009 Posts: 1802 Location: Parker, CO
Posted: Tue Jun 27, 2017 10:58 am Post subject:
Looks like you need to split the cases. I found this on the 2stroke forum.
If you have a Yamaha manual it is step by step in there.
Basic Metric tools needed + impact wrench -air recommended
Engine out on bench time frame [40 minutes to 1 hour]
engine tear down - [30 minutes -50 minutes]
Crank out- 1 minute
Lots of things you need to keep track of, have plenty of freezer bags you can make notes on + pictures [camera recommended 1st time]
Some helpful hints;
loosen head bolts in frame
Drain oil in frame
Make a stand out of wood for engine 13" x14" 2x4's - will save you some struggle
Disconnect electrical plugs from engine -remove battery
disconnect tack cable /clutch cable
remove spark plugs
Disconnect chain @ master link
Move all cables out of the way RD350 & 400 engine exits to right [sitting on bike]
remove engine to frame bolts 6 total
Engine weight = aprox 100 -110#
Place on bench
remove generator assm - pin that locates generator if loose bag with gen]
remove top end- rags around pistons so studs do not mar pistons.
remove right side cover -oil will come out
loosen nuts -clutch nut 27mm / primary drive crank 26mm - impact drive
Remove top case bolts - 10mm socket
Flip over engine - remove bottom case nuts - 12mm socket
Flip right side up
smack with dead blow hammer -or soft face hammer front of case [do not ply on any surface]
You will hear it come loose a hollow sound, work the top case off -studs go through engine]
now you can get your crank out.
Note all bearing alignment keepers- bag those and mark where they go.[i] _________________ ...the era is gone forever, fortunately the motorcycles remain...
Joined: Jul 10, 2008 Posts: 3145 Location: Galveston County, Texas
Posted: Tue Jun 27, 2017 12:39 pm Post subject:
At first, I was thinking, sure, you can replace the right-side outboard crank seal without splitting the cases but after looking at pictures of crankcases and seals on ebay..... now I'm not so sure. It looked like the seal itself had a groove/recessed area?..... Just not sure. Take a look at the parts fiche, pictures of the seal and crankcases on ebay and see what you think. That sucks if you have to split the cases just for an outboard crank seal.
BTW.....don't be such a stranger around here, I'm tired of paying your member dues for you. _________________ _________________________
GONE.......WITH A PUFF OF SMOKE AND A BLUR OF SPOKE
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