Montesa 4RT Transmission oil leak into engine oil - crank seal?

[mil]

Hi guys

I have a 2015 Repsol 4RT that has been amazing to ride and I regularly change the engine oil/ transmission oil. On the last change there was barely any transmission oil at all! I have done some searching on the forum and this has been mentioned before - with the crank seal apparently the culprit? Has anyone experienced the same and did this change solve the problem?

I'm looking to have this changed, and not experienced opening up the engine so would doubt its a job for me -  can anyone recommend a good shop local to Birmingham/West Midlands who'd have experience with Montesas? (BVM?)

I was quoted by a Montesa dealer in Yorkshire but don't want a long drive to drop it off/ collect again! Must be someone closer I'd hope.

Thanks

Mil

Edited August 9, 2023 by mil

[garygasgas]

fred adams in gloucestershire is your man. brilliant with montesas. used to work for b.v.m but now is freelance. firm is called g.l. motorcycle tech. sorry cant find his number but b.v.m would have it. hope this helps. 

[garygasgas]

just found it. freds number is  07557 430777 . worth a call .

[mil]

5 minutes ago, garygasgas said:

just found it. freds number is  07557 430777 . worth a call .

Thanks so much - that is really helpful and sounds like just the man to call. I really appreciate this Gary.

Mil

[lemur]

On the last oil change when there was barely any transmission oil at all, was the engine oil level overly high?  

[mil]

10 hours ago, lemur said:

On the last oil change when there was barely any transmission oil at all, was the engine oil level overly high?  

I honestly didn't take enough notice as I dropped the oil into a pan - so it may well have been but not sure. When I dropped the transmission oil there was just a dribble which was worrying. But I haven't had any leak and from the searching I wonder if its the crank seal?

[lemur]

5 hours ago, mil said:

I honestly didn't take enough notice as I dropped the oil into a pan - so it may well have been but not sure. When I dropped the transmission oil there was just a dribble which was worrying. But I haven't had any leak and from the searching I wonder if its the crank seal?

The engine still runs and doesn't sound like it has a bad main bearing?  It would need to be the right hand side because the alternator side contains engine oil.

... I'd be tempted to change the fluids, ride it and see if the engine oil level increases, if not then that's not where it's going.

[mil]

On 8/9/2023 at 1:39 PM, lemur said:

The engine still runs and doesn't sound like it has a bad main bearing?  It would need to be the right hand side because the alternator side contains engine oil.

... I'd be tempted to change the fluids, ride it and see if the engine oil level increases, if not then that's not where it's going.

Thanks for the responses Lemur.

The bike has been running faultlessly and with no problems at all. 

I dropped the transmission oil last night (after noticing the low oil level I changed it and rode it 2-3 times with no problem). Transmission oil was at 0.47L (spec 0.54L) so a little low but may not have drained completely.

Engine oil was bang on spec at 0.41L...

As you suggest I think I will refill to spec, ride and then change again in a few rides and keep an eye on it.

Thanks for the input.

I've also phoned Fred and chatted it through with him - he said he'd be surprised if it was crank seal. He's a top bloke so if anything is needed to be done I'll be taking it to him!