Topic: oil overfill now it leaks!!

[jvalbuena]

Had my '77 CB750f2 motor rebuilt last winter. Leaked oil like crazy after the rebuild so I took it back to the same guy. He took it apart and put another new gasket kit in it. No more leaks! Then I overfilled it with oil. These bikes are such a pain to get all the oil out of. I thought it was drained totally so I put in just under 4 quarts (it has an oil cooler). Turns out I put in about more than an extra quart. I'd love for someone to tell me that's the reason it leaks from around the head gasket now and that once I drain the extra oil and get it back to normal level it will stop leaking. But if you must, I'm also prepared to hear " You dumbass, now you have to tear it apart again and put in yet another gasket kit."

[Lumbee]

...maybe nobody has replyed cuz they hate to break the news to ya.     First off, it doesn't sound right that overfilling it would blow the head gasket, thats what the overflow tube is for in the oil tank.  However, a leaky gasket is a leaky gasket, whatever the cause.  How do you know u overfilled it?  Just because of the leaky gasket?  The oil bag should be about 3/4 of the way full.  If it leaked before, maybe u'r mechanic isn't so good at his job.     So I would get the oil level right, then if its still leaking at the head, you need a new gasket.  I'd consider doing it myself, or finding a new mechanic...

[eldar]

Could be crappy quality gaskets too.
But a 750 holds about 3.7 quarts of oil so if you hit the kicker a couple of times to help get oil out of the transfer tubes then you will probably fill about 3.5 quarts as it seems about impossible to get ALL the oil out.

[scondon]

    After a regular oil change(F2) that includes changing the filter it takes me just under 3 qts. to get the level back to full. Run the engine for a minute and then check the level with the dipstick. If you need to remove oil you can do that easily by removing the drain bolt on the oil reservoir tank(behind the sidecover). Definitely a good idea.

    I've rebuilt three engines thus far and I gotta tell ya, it takes a lot of work to insure the new engine doesn't leak. After all, the engines are over 27 years old and have gone through countless heat cycles. I'm usually happy just to have the "rivers" of oil change to minor "weeping". The most common "rebuild" leak i've encountered comes from the pucks under the cam towers. The oil works it's way down through the spark plug holes and out onto the cooling fins and may appear as a head gasket leak. Also, any tach cable leak can work it's way to the fins.

   

[zhirkhan]

Hello, I am new to this site and I am having this same problem. The oil appears to be leaking from between the right side exhaust ports, it is above the head gasket, and starting today it turned into a "river" of oil.
This engine was rebuilt about 4000 miles ago according to the previous owner. Before I overfilled it (dumbass) it was only leaking from around the neutral switch, and then only a few drips.
Anyone have any suggestions?
Thanks,
Jon

[seaweb11]

Hello, I am new to this site and I am having this same problem. The oil appears to be leaking from between the right side exhaust ports, it is above the head gasket, and starting today it turned into a "river" of oil.
This engine was rebuilt about 4000 miles ago according to the previous owner. Before I overfilled it (dumbass) it was only leaking from around the neutral switch, and then only a few drips.
Anyone have any suggestions?
Thanks,
Jon

Right hand side, near the top.....could it be where your tach cable goes in? Those little gaskets get real hard and tend to leak.
Just a thought

[zhirkhan]

It's not from the tach cable. There is pretty much a steady stream of oil coming out of the space between the right side spark plugs, above the head gasket, but behind the frame where I can't see very clearly. I'm afraid that there may be a crack in there somewhere, but I'm hoping it's just a seal. I can't ride the bike because the leak is too huge. I'm guessing that I have to pull the motor and have a closer look.
Any other suggestions on a likely source of the leak?