77 XS750D Tach Drive Oil Seal

Goey750

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My '77 XS750 has a slight oil leak around the seal where the tach cable connects to the engine. I replaced the cable thinking that might stop the leak, but did not replace any o rings or seals. I've been trying to find the part so I don't have to take it all apart and have it off the road while I wait for the new seal (it's only a tiny bit of oil seepage when riding) but am having trouble finding the correct part. I keep seeing oil seals for 78 XS750's and am wondering if its the same (https://www.mikesxs.net/yamaha-xs650-oil-seal-tacho-drive-oem-93104-07036.html). Can anyone confirm for me? Thanks!

Joe
 
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Haha! I see 5Twins beat me to it! :laugh2: I bow to the master, everything I know about this job, I learned from him! :thumbsup:
There are actually two components to sealing the tach drive assembly. The seal for the shaft itself and an oring that goes around the shaft housing, it is also prone to leaking, they are both available from Mikes,
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Here are some reference photos of what the assembly looks like,
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Pressing the new seal in place with a socket,
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I’ve done a couple of these jobs with the right side engine cover off, you might be able to remove just the shaft housing to replace the seal and o ring, but you would have to be careful to keep the tach drive shaft pressed firmly into the engine case. Because there is a tiny washers at the end of the drive gear on the shaft , that will fall off if you pull the shaft lose from its engagement.
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Thank you both, and thanks for posting the guide! Ordered the parts, plan on doing all the rubber/seals replacement at some point this season. I'll post some pictures soon!
 
You have already ordered but for future reference most bearing supply places could sell you that seal. Its a 7-13-4.. Take the part and those numbers with you when you go.
The O ring might be harder but I would give them a try. The best place for O rings in my town is a hydraulic hose repair shop.
 
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