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Collection, Preservation and Display of Old Lawn Mowers

Suffolk engine advice please

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Hello, what a wonderful website full of useful fascinating information. Great to read about people restoring these wonderful old machines.

I wonder if any of you could give me some advice please?

I have just bought a Suffolk Colt 75G14 10 which I intend to restore, it would appear to have had a fairly hard life. I have removed and stripped the engine having run it very briefly. The crank journal and con rod big end are scored to the extent where I believe they ought to be replaced, the key way at the flywheel end is also badly worn as it hadn’t been tighten correctly which also led to the flywheel splitting (I’ve sourced another) Additionally  the rings have in excess of 20tho gap,I read somewhere that the ring gap should be no more than 10tho,.  (the bore may be worn too but I only intend to fit new rings if I can get away with it). The valve stems are also fairly sloppy.

Having  looked at the manual for the Colt here on the Old Lawn Mower Club it appears that it’s for a different engine the 21A and the part numbers listed differ to those stamped into the components in my engine. 

My questions are, do the parts differ from engine to engine for all the 75cc engines or are they interchangeable? For instance my crank has the part no’ E3524. The manual listed here for the 21A show the crank part no’ being E8142.

The exploded diagram of 21A leads me to believe that the valve stems can be replaced, how are they removed? I am familiar to an extent with removing and replacing them on car engines but not small engines like this. They clearly need to come up towards the valve seat as there’s not enough clearance underneath them to press them through with the new valve stem as can be done of some car engines. 

Finally where might I source spares for this engine and the mower? I’ve bought a few bits from eBay but can’t find a crank or the other bits I mention above.  

Any advice would be gratefully received. 

 

 

 

 

 

Forums

wristpin Tue, 05/03/2019

Welcome,

By the sound of it you are right about your engine having had a hard life . Personally I wouldn't bother trying to recondition it. There are plenty of relatively unworn and unmolested engines out there for peanuts in far better condition than yours will ever be. 

Valve stems - do you mean guides? The stem is part of the valve, the guide the bit that the stem slides up and down in. As above I certainly  wouldn't bother.. 

Suffolk Jim Wed, 06/03/2019

Wristpin thanks for your response. Apologies yes I meant guides.

where might I source another engine? I looked at eBay and the options seem a little limited at the moment. 

wristpin Wed, 06/03/2019

I know what you mean, the thing that you want is always at the other end of the country.

Spread the net a bit, Gumtree tends to be a bit more local. I don’t do Facebook but I know people who have success acquiring and disposing of all sorts of things. Your local Freegal group may be worth investigating  and there are still some local free newspapers.  House clearance people. Our local agricultural auction market  hold monthly collective sales of garden machinery sales and old Suffolks seldom make more than 5-10  quid.

I see that you are in Ipswich; Suffolk’s were made in Stowmarket so there may be an “indigenous “ population in that area!!