Mountfield Sp536 valve clearances

[Richardsth]

does anyone know what the valve clearances should be for a Mountfield SP536 lawnmower fitted with a RM55ES engine? Mine is having problems starting up again after it gets hot, and everything else has been looked at.

Thanks All.

 

[Burnerman]

Go for 0.10mm hot and you'll not be far off!
OHV engines have a screw and locknut, side valves require the end of the valve stem grinding down.
John

 

[Richardsth]

Actually, I rang up servicelink today and they gave me the following information

Inlet valve 0.10-0.15
Exhaust valve 0.15-0.20

I don’t know how true they were as my mower was well out. I’ll try it when it’s hot next time as that’s when it seems to be having problems.

Cheers Rik

 

[Burnerman]

With the engine steaming hot, whipping off the rocker cover and checking that you can still rotate the pushrods will give you a pretty good idea of how things are.
These engines are prone to running hot, and fuel evaporation isn't unknown.....a tip is to give it just a shot of choke whilst pulling the cord-without over doing it, of course!
John

 

[Nige F]

[QUOTE="Burnerman, , side valves require the end of the valve stem grinding down.
John [/QUOTE]
Have you ever done that to a SV mower engine - I can't imagine them lasting long enough to need that

 

[Burnerman]

Aye, they are getting less common due to their inefficiency so the OHV / OHC engines take over.
Some of the large iron cylinder Briggs motors are SV though - and they have 'proper' ball bearings supporting the crank......a different machine indeed to the basic bushed engines of yore.
John

 

[Richardsth]

Just to get this thread back on track, servicelink did send me a workshop manual for this mower and it’s titled wbe-701, wbe-702 and wbe-704. I’ve attached it to this reply, so hopefully it will show up below.

Cheers All.

Rik

 

[hardtail]

do you have the number for the service link people as im after the valve clearence on a rm65 engine

 

[Richardsth]

You’ll find all the info here.

http://www.servicelink.org.uk/