Engine gasket ??

[Ati]

I have a problem with Aprilia RS50 2003 engine gasket, I strip it down to change oil seal and crank bearings, and realised it had no gasket between the 2 engine cases, I cannot find anything all over ebay and internet, they aparently only go from 2006 and onwards. Has anyone got any information about this or should I leave it as it was?

It should look something like this

https://www.google.pl/search?hl=pl&site ... _BTBf3M%3A

[iangaryprice]

Are you talking about the 2 engine cases that split to get the crank out.

These don't have a gasket, they just use sealing compound.

During manufacture the cases are bolted together and then the final machining is done.

They they unbolt them to build the engine.

They have to be accurate, putting a gasket in between would lose the accuracy.

The manual for your bike should tell you which compound to use.

There are several different types - colour coded!

[Ati]

Shouldn't there be a gasket on where I've pointed going around it? Or completely free?

http://i67.tinypic.com/29ek8b8.jpg

http://i68.tinypic.com/ic4t4k.jpg

[eastanglianbiker]

no gasket for there as its been said its just silicon gasket sealant

[Joeman]

The rotax 123 engine from the old aprilia 125 bikes had a gasket there.. But silicone will do.. Just don't use too much and bung the engine up!

[eastanglianbiker]

The rotax 123 engine from the old aprilia 125 bikes had a gasket there.. But silicone will do.. Just don't use too much and bung the engine up!

the op has the 50cc engine not the 123cc would they be the same ?

[Joeman]

The rotax 123 engine from the old aprilia 125 bikes had a gasket there.. But silicone will do.. Just don't use too much and bung the engine up!

the op has the 50cc engine not the 123cc would they be the same ?

 

No idea, but every two-stroke bike i've split open had a gasket there.. i didn't always put one back though - instant gasket is wonderful stuff when you cant get the gasket you need in a hurry!

[eastanglianbiker]

ive never split a set of crankcases that have had a gasket,ive only ever done british and jap stuff tho

[Joeman]

Random image of a Ktm 300 motor split in two..

[iangaryprice]

Shouldn't there be a gasket on where I've pointed going around it? Or completely free?

http://i67.tinypic.com/29ek8b8.jpg

http://i68.tinypic.com/ic4t4k.jpg

 

If a gasket is to be fitted there I would expect to see a small step about the thickness of a gasket.

Put he two halves together and see if there is a gap.

If there is a gap you need a gasket.

If no gap just jointing compound on all the faces that mate together.

Was there one there when you too it apart?

[Joeman]

I have a problem with Aprilia RS50 2003 engine gasket, I strip it down to change oil seal and crank bearings, and realised it had no gasket between the 2 engine cases, I cannot find anything all over ebay and internet, they aparently only go from 2006 and onwards. Has anyone got any information about this or should I leave it as it was?

 

 

Aprilia RS50, 1993 - 2005

http://www.pjme.co.uk/acatalog/Aprilia- ... -2005.html

Bottom end rebuild parts:

http://www.pjme.co.uk/acatalog/Aprilia_ ... m_End.html

[Ati]

There was just a bit of grey compound sealing I guess.

[tilertim65]

Crankcase halves don't have gaskets due to machined clearances. Manufactures recommended sealant is best or red Hermetite if hard setting recommended, silver if non setting recommended.

Never use silicone sealant on wet casings it should only be used to keep water out not oil in eg ignition or electrical covers.