Jump to content
Sign in to follow this  

1990 KDX 200 Gearbox Oil Issues

Recommended Posts

I recently acquired a 1990 KDX200. The bike runs reasonably well for it's age. The first ride over 30 min the gearbox oil started overflowing into the airbox (overflow hose is routed to airbox). The oil that overflowed and the oil in the gearbox are an odd shade of dark forest green. The oil appeared to be overfilled slightly which explains the overflow. What I don't understand is the weird dark blueish greenish gray color of the oil.  I believe the PO used motul 10w40 ester gearbox oil because he gave me a half used gallon. I use Motul 710 2t oil which is blue, and run green coolant in the radiator. I drained the gearbox oil and there was a nice little clump of dark gray metalic paste on the magnetic drain plug, which should explain the gray hue. What I do not understand is the greenish blue hue. Anyone know what in the heck is going on with this old horse?
The pic shows a sample of my drained oil. When held up to the light it turns more of a green color. Oil still feels slick as can be.

20180924_141537.jpg

Edited by frontline510

Share this post


Link to post
Share on other sites

I think your alright,the metallic paste is clutch material(normal).I would change the oil and monitor it,I know schaeffer's oil is green,could be more brands.i don't know about the trans breathe hose being in the air box might be fine and I see the purpose of you ride in water a lot but could it create a vacuum and pull the trans fluid from the trans?I wouldn't think so but maybe. How much was in there?if it were antifreeze it would be a milky mess,but watch the coolant level to make sure your not loosing any.

 

 

Share this post


Link to post
Share on other sites

The coolant level in the radiator and overflow container have never dropped. The coolant looks new. I just changed the gearbox oil today. I took it out for a 30 min ride. Same leak from the overflow. You may be on to something about the vacuum affect. Tomorrow I will clean out my airbox (again) and try pulling the overflow hose out of the air box. I will zip tie the hose elsewhere and plug the hole in the air box. Thanks for the advice.

Edited by frontline510

Share this post


Link to post
Share on other sites

If your not in a lot of water you should be fine to let the hose hang off the back of the cases with the carb vents.

Share this post


Link to post
Share on other sites

If you had a vacuum problem, would it not suck air and dirt into the engine? If you had a pressure problem, it might blow oil out.

 

What is your transmission oil filling procedure? (This is the "make sure he is doing it right" portion of trying to help someone) 🙂

  • Like 2

Share this post


Link to post
Share on other sites
18 hours ago, KDXGarage said:

If you had a vacuum problem, would it not suck air and dirt into the engine? If you had a pressure problem, it might blow oil out.

 

What is your transmission oil filling procedure? (This is the "make sure he is doing it right" portion of trying to help someone) 🙂

What I was questioning was whether it is possible that air filter is sucking on the overflow hose.. The hose sits on top of the air filter. Either way I really don't think it belongs in the airbox. 
To change the tranny oil I rode the bike for 5-10 min to warm up and circulate the oil. I drain from the drain plug underneath. I let it sit until it stops dripping, then move the bike around to get more out until it stops. Put the plug back in. I start filling with approximately .7L (the manual calls for .8) Then I level the bike and check the sight glass and add very slowly until it reaches halfway up the glass. 

Edited by frontline510

Share this post


Link to post
Share on other sites

It sounds like you are doing it right. I will go with Kawasaki's engineers over your analysis on the vent hose.

 

You might want to look into a pressure and vacuum test on the engine to eliminate that.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×
×
  • Create New...