Free Lawnmower

No progress on the topic of the last thread yet, will try and get some time on that over the long weekend if the Renault timing belt change doesn't throw up any problems,

Dad's friend gave him this ride on lawnmower for free...

Looked pretty good, needs a bit of welding to the mountings of the pedestal the steering wheel goes through and a bit of a re-rig on the various linkages to get it sweet

Started stripping it down, wiring was all sound, needs to be routed and secured better

The engine would only rotate about an 1/8th turn each way, I was hoping that this was just some part of the drive system underneath catching so everything was disconnected from the output shaft of the engine, with everything disconnected the problem remained so next step is head off. Simple job on a side valver.

Cylinder head bolts

With the head off it was found that the piston moved independently of the crank, hohnoh

Needs to be opened up.

Head off and getting the engine on the bench

Engine up on the bench, the tail of the 'oil' pouring out of the filler shows how viscous this oil was, it was tar really

I didnt think about getting the flywheel off first so temporarily bolted it back to the chassis and removed it with an improvised puller

Flywheel off

Time to open the crank case

It was a mess inside

Camshaft gear well out of mesh with the crank, counterweight broken free from the crank

Chunk of 'big end' with fastener still attached so the bolts didnt let go!

Broken counterweight, its retaining rod disconnected

Smashed up counterweight assembly

Broken pieces, notice how oil free the rod journal on the crank is!

One galled up journal surface, this was the cause of the failure, no oil and it seized

When the bearing locked up it broke the rod, then imbalance and broken bits jamming the works caused failure of the counterweight 

Amazingly the crank case survived

Looks like the piston has been replaced before, showing less wear and colour than other parts

Cleaned up a bit

All the cooling fins on the cylinder and all the ducts on the flywheel fan rotor where packed with grass, I think that with age and overheating the oil has gone to shit and formed the horrible tar that was left. Oil starvation to the crank piston journal then caused failure of the big end bearing causing the rod to go.

The case, camshaft, piston and governor assembly seem to be salvageable, but everything else is shagged.

Parts list sees a crank, con-rod / gudgeon pin and counterweight assembly added to ze list.

More on this and the mower as they get sorted.

YeeHaaah