Crank seal behind small bevel

frank66 said:

twist a screw or two in it then pull it out. curb drops and pipes break woodrufs. i explained allready how i tack weld mine on.

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2door said:

Most any vendor who sells parts can provide seals. Be specific when ordering. The one on the right, behind the gear is different than the one on the left behind the magneto rotor.

Any small tool, screwdriver, metal hook, etc. can be used to pry the old seal out. The new seal lip should be lubricated with your oil, slid into place then driven into the case with care. It needs to go in absolutely square. There are seal driving tools but a deep well socket of the appropriate diameter will work too. The socket needs to be just a hair smaller than the outside diameter of the seal. Tap, don't hammer it in. You'll feel when it seats in place.

Good luck.

Tom

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2door said:

I've never seen a seal in that bad a shape. You're correct. It looks as if it has "melted".
I can only guess as to what happened to it. Excessive overheating maybe? You didn't try "welding" that gear on did you?

Clean it as best as you can. The machined bore where the seal goes must be clean and have no deep scratches or scars. Be careful cleaning it. The crankshaft too must be clean and free of damage or defects. The rubber lip of the seal is in contact with the shaft. No roughness or the seal won't last.
Pick out what you can from the bearings. Try a small magnet to make sure there's no steel in the bearings. Clean everything and install a new seal.

Good luck.

Tom

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frank66 said:

all evidence suggests that a tack weld at any point till now/ and you would be 125 dollars richer and be riding it now. but 2door disagrees with me and your on the hunt for a new engine. CLASSIC

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maniac57 said:

Tack welding the crank is a BAD idea frank66. PERIOD.
I don't care how it works for you, it's a terrible way to "repair" a crank key.
Unless the keyway is simply GONE, it's bad advice.
And as far as the original poster's issues...
I can't tell if it's actuall melted or if it's the bad pic. If it IS really melted, you have a paperweight. Any engine getting hot enough to melt a main seal is going to have WAY more problems than a bad seal.
FIRST thing to do is get all the old seals out and look at your mains. (I'd replace both seal as a set)
Then pull the top end and see if the damage really WAS from overheating. If you find damage, your mains are probably toast.
While the top end is off, the gear and magnet and the seals out, you can carefully spin the crank and feel for any roughness or crunchyness in the main bearings. With no seal drag it is much easier to tell. (Remove the magnet to get the other seal out)
The THICK seal goes on the gear side when replacing, thin on the magnet side.
CHECK THOSE MAINS!
Fix it now or fix it later...bigger.

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maniac57 said:

Yes. The drive gear could have been spinning on the crank which could cause extreme heating due to friction.
If this is in fact what actually happened, I'm POSITIVE you have a BADLY damaged crank. If there is any keyway at all left, I doubt you will ever get a key or drive gear to fit properly again.
If this is the case, be prepared to replace the engine or bottom end.
Post some good clear pics of the end of your crank with the keyway and hopefully we can tell better what's going on...
But from what I can see (not much) your crank looks okay to me. If it spun long enough to melt a seal, I would expect clear and visible damage.

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frank66 said:

frank66 said:

all evidence suggests that a tack weld at any point till now/ and you would be 125 dollars richer and be riding it now. but 2door disagrees with me and your on the hunt for a new engine. CLASSIC[/QUOTE


state advice but please respect mine too cause the engine is still busted after 2 weeks of mishaps.

we are great opininated people here so u get more than 1 correct answer often.

stating its bad advice like a pop song chorus offends me as a customer and a forum member.

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A tack weld would seem logical but this is my first build you can bust my chops all day about how i have been having problems. Im new to this cut me some slack..... But logically if the bevel gear ever shreds or the teeth wear down how would you replace the gear? And By the way I work alot if it takes me years to get it right thats my problem maybe ill got to another forum if your issue is about my time.

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frank66 said:

you should see my gasbike sometime madmax.

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