Crankcase Engine Gas Gas 280 Help

[Gines]

Hello, recently i bougth a Gas Gas 280  TXT Pro 2002. At first it work well, but then, it loses oil the left crankcase. Morover, he lose oil crankshaft seal in to the engine, so the compression pass to the gerabox. My cuestion is, its posible put the crankcase to the other year? What year is compatible?

The referency is : MT280210000

Can i put for example the MT280310000

 

Sorry for my inglish, if you don't understand something teld me.

[peterb]

Hola Gines, tu inglés, no problema yo entiendo perfecto. I think you can swap over to a newer crankcase but these are very expensive. Why don't you strip down your motor and find out what the problem is, if it is just an oil seal then this is an easy repair. On the 2002 motor, they had a traditional main bearing with separate viton oil seals, from 2004 Gas Gas changed the bearing to a wider design with integral oil seal. If your motor has the original type of bearing, then it is possible the left side crankcase seal has failed allowing crankcase pressure to force gearbox oil out of the breather, or perhaps the crankcase gasket has failed. Note that the 2002 crankcase gasket is specific for this year and any later gaskets will not fit. You should be able to buy the old type oil seal and 2002 crankcase gasket in Spain, if not I have them here in NZ. Also, on the left side of the crank shaft there is a second oil seal to prevent oil entering the magneto housing (el encendido) this should be replaced also. Remember that the oil seals have a lip sealing spring and these must face inwards toward the crankcase. Bye, Peter B.

[Gines]

10 hours ago, peterb said:

Hola Gines, tu inglés, no problema yo entiendo perfecto. I think you can swap over to a newer crankcase but these are very expensive. Why don't you strip down your motor and find out what the problem is, if it is just an oil seal then this is an easy repair. On the 2002 motor, they had a traditional main bearing with separate viton oil seals, from 2004 Gas Gas changed the bearing to a wider design with integral oil seal. If your motor has the original type of bearing, then it is possible the left side crankcase seal has failed allowing crankcase pressure to force gearbox oil out of the breather, or perhaps the crankcase gasket has failed. Note that the 2002 crankcase gasket is specific for this year and any later gaskets will not fit. You should be able to buy the old type oil seal and 2002 crankcase gasket in Spain, if not I have them here in NZ. Also, on the left side of the crank shaft there is a second oil seal to prevent oil entering the magneto housing (el encendido) this should be replaced also. Remember that the oil seals have a lip sealing spring and these must face inwards toward the crankcase. Bye, Peter B.

Hello Peter B, Thanks for the answer. As you say this motor has the original type of bearing,  the left side crankcase seal has failed allowing crankcase pressure to force gearbox oil out of the breather. Moreover, this motor leaks oil entering the magneto housing (the ignition) because has a crack. I think its not possible repair, it was repared with  putty car.   Here in spain i  i found the crankcase engine gas gas 280 txt pro 2003, the 2 , left and right 150€. The problem is his engine, because he have the modern sistem, only one seal (magneto) and the other is including in to the bearing. Its compatible 2002/2003?
If its compatible, i only need go to the turner to to remove the false bushings from the crankshaft.

In what page you buy replacment in New Zeland?

Greeting 

 

[peterb]

Hola Gines, yes the crankshaft (cigueñal) from the 2002 motor can be used in the 2003 crankcase when the spacer sleeves have been removed from the shaft, they should not be too tight and you may be able to get a bearing puller behind the sleeve to extract it. Before buying the 2003 crankcases, have a look to see that there is no crack on the bottom gearbox mounting lug. I will send you a message via Trials Central. Bye, Peter B.