Hi all

I've just had a new piston kit put in because the radiator had worn a hole in its self over a few years (fan) - and had not cooled the engine which ruined the piston;(

Any way - they sent the rad off to be mended.

(before i sent it to them i had changed the gearbox oil after a trial and not used it since)

Got it back last night .and started it up and rode round for a few minutes this morning And the gearbox oil was white after the ride.

I am guessing water in the oil? When they took the rad out do you think they could of damaged the water pump /seals? If so its going straight back!

Is this cheap to mend?

Thanks

Ben

I would change the oil and try again. When they had the motor apart to redo the piston, some of the water could have gotting into the motor.

Good luck

Ben

your correct that white or milky (emulsified) oil is likely to be water in the oil.

it could be that the inner water pump seal has failed.

couple of questions to rule out other causes:-

• When you replaced the piston, did you remove the clutch cover or drain/replace the gearbox oil?
  
• Have you seen water leaking from the small tell-tale hole located on the underside of the water pump housing?
  
• Have you unexpectedly needed to top-up the cooling system water level?
  

Dom

Sorry - just looked at the bill and they said it had no coolant in because the fan had made a hole in rad.

So would not be what BESTRCPILOT posted above.

It also says that they put a new water pump o ring. Could they of messed up the pump seal some how.

Thanks

Ben

Hi Ben

When you say you sent the rad away, I assume you mean the whole bike. Its unlikely that they have damaged your pump seals but this is often the cause of water in the oil, as you have already concluded.

The.seals could have been damaged either when the piston damage happened, or when the piston was replaced by contaminating the cooling fluid, could also be due to not flushing the rad after the repair.

Seals are not expensive and quite easy to change, so I would change them, and flush the cooling system and change the gearbox oil and hopefullyit will be sorted.

TLTEL

Hi Dom

I didn't take The clutch cover off and neither of the two things have happened that you mentioned.

But when I sent the bike of I had just changed the gearbox oil before it went . and it had NO coolant in it

Because the rad had a hole in it.

Hi

Tltel I think I'll let the the guys who did the damage mend it !

If they did it?

But thanks anyway:-)

Will it damage the gearbox if I carry on using it

Ben

So you wanted a Gasser did you?

Honestly, I find it more likely yhe water pump seals may have been on their way out or damaged due to dry running due to the leaking rad, but you will not know this untill the integrity of the cooling system repaired and the bike is ridden, such as this case.

In many cases, there is no way to tell in advance. No ones fault, just get it fixed!

ShercoBen

Ok, the water pump seals are an easy fix, probably 30-45 mins if you know what your doing. Also the parts are less than 10 pounds (so long as the water pump shaft is ok).

Like Copemech says, difficult to say who's at fault, probably best to just get it done.

Dom

I would bet the water pump seal got hot when the motor overheated and was dry with the shaft spinning in it and that caused the failure. It would be like a secondary failure attributed to the original failure of the hole in the radiator. Same reason the piston got hot, seized and needed to be replaced.

I think the water pump O-ring they replaced is for the water pump cover sealing to the case and has no affect to the water pump shaft seal which would leak into the gear box. Check out pages 64 and 65 of this manual parts numbered 3 and 4 in the exploded view on page 64

http://www.trialspartsusa.com/manuals/Despiece_TXT_Pro_2008.pdf

I just recently purchased a 2003 Gas Gas 300 and am trying to get familiar with the motors and where to get info. So far I am very pleased with my choice to switch from Sherco to Gas Gas.

I am surprised that nobody mentioned the possibility of water leaking past the O-rings under the head. They can get out of position when reassembling the head after replacing the piston.

Don't run the bike with milky oil. Water is not a very good lubricant and you don't want to have to do another repair.

Let us know what you find.

I am surprised that nobody mentioned the possibility of water leaking past the O-rings under the head. They can get out of position when reassembling the head after replacing the piston.

Don't run the bike with milky oil. Water is not a very good lubricant and you don't want to have to do another repair.

Let us know what you find.

Yes but how could water get to the gearbox??

TLTEL

If you replace the WP seal and the shaft is worn - it will leak still. I would seem to think a dealer would know that - but...

If you replace the WP seal and the shaft is worn - it will leak still. I would seem to think a dealer would know that - but...

Generally the new seal will work for a time but it's functional life will be a lot shorter. Not sure why they had the W/P out as

they replaced the o-ring. They might have seen some oil leakage around the W/P body as, if not installed correctly, the o-ring

will often be shaved in half when the pump is installed.

It's a long shot, but check that the overflow tube off the radiator cap is not being crimped when the fuel tank is installed. It's common

to overfill the radiator and not usually a problem as the extra coolant (due to thermal expansion) will just piddle out the overflow tube.

But, if that tube is crimped, the higher pressure in the system will force the "extra" coolant past the W/P seal and into the trans case.

It doesn't take much coolant to froth up and cause the described symptoms.

Jon

Yes but how could water get to the gearbox??

Jon's message above me can be modified by how big a groove is on the shaft. I had one, early in my experience that the shaft was so bad the new seal wouldnt do anything, being a newb I didnt know that the groove was NOT a "design" so expert help intervened and I was fixed with new shaft. if you get the actual "new" kits, the shaft is finally hardened enough to not wear a groove every year, which means you shouldn't have buy a kit each year, knock on wood. (year or so was my schedule... due to hours of riding a year of course)

As far as How does leaking oring on head cause water in oil?

Well, here's how. The seal around the water-pump can't hold a candle to the pressure from Combustion, so what it seems to do is pulse high pressure into the water jacket, which then pushes water into gearbox at water pump seal.

We've already explained that we KNOW, if the overflow hose is crimped, and you have just filled the bike with coolant, when you ride, pressure builds up in the coolant side, pushes the excess water into gearbox, around the WP seal, instead of out the overflow. Combustion pressures are worse.

Last guy on here or another forum found that he heard a sound when bike was running, after changing his head, which alerted him that the o'rings had moved on him upon installation of the head, there is a trick and "hope" to these o'rings BTW... I have no idea what he heard, but he made me think of a reed type musical instrument, mouthpiece only, being blown on...

Edited December 4, 201213 yr by sting32