Model 30 engine breather

[chris goldson]

Some help if possible.

Due to take the primary case off just to give everything a good clean and inspect the primary chain and thought I would strip engine/crank breather whist in there.

Is this a tricky operation ?

[chris goldson]

Also does anyone know if the valve release assembly part no 025526 will fit my 1956 model 30 please

[Groily]

Crank pressure relief valve.jpg

No, not tricky. Should be 4 bits - big bolt, spring, small fluttering disc and smaller bolt. Pic taken from AMOC Spares Twin Engine parts lists, about page 5.
Should be the right bit I think, yes, for 1956.

[clive]

Also does anyone know if the valve release assembly part no 025526 will fit my 1956 model 30 please

According to the club spares scheme that part is for 57 on twins. The part Groily has shown is part number 016673/4 (and also some other part numbers) which is listed for 52 to 56. Both parts are listed as available.

[ajscomboman]

Also does anyone know if the valve release assembly part no 025526 will fit my 1956 model 30 please

According to the club spares scheme that part is for 57 on twins. The part Groily has shown is part number 016673/4 (and also some other part numbers) which is listed for 52 to 56. Both parts are listed as available.

025526 won't fit a correct 56 model 30 crank as the thread size is different. A correct 56 crank with shock absorber has a 1/2" dia thread and uses 016673/4 a non shock absorber 57 on crank has a 5/8 20TPI cycle thread

[Groily]

Sorry - didn't check part #s, assumed we were talking 1956 as per Q. One should never assume . . .
But as ajscombo says, all the bits are available if needed.

[ajscomboman]

Also does anyone know if the valve release assembly part no 025526 will fit my 1956 model 30 please

According to the club spares scheme that part is for 57 on twins. The part Groily has shown is part number 016673/4 (and also some other part numbers) which is listed for 52 to 56. Both parts are listed as available.

Time to go to SpecSavers Clive, 025526 might show on the website but stock availability is nil! However we are currently having them made as I type so fingers crossed one day they'll turn up.

[chris goldson]

I went round to see my friend who has just taken the breather off his 650 twin and whilst the breather assembly is larger than the one on my model 30 the threads are all the same so I am assuming that the later one can be fitted?

Mine is fine now with a thorough clean and re-assembly.

Thanks as ever for the help.