It still ran..

[shenion]

Picked up a free Craftsman 12HP riding lawnmower with bagger. Engine did not run. Cleaned up some electrical connections, charged battery, filled gas and it started right up.

Engine had nasty knocking sound. Below is a picture of the bottom pan of the engine. Schrapnel from a connecting rod as part of the counterbalance. This was only a symptopm of the real problem. The upper journal of the counterbalance was warn waaay oblong (counterbalance is a big square weight that moves opposite the piston.)

A small engine guy said that's what goes on these when it runs low on oil. The upper counterbalance journal is at the top and is first to be starved.

Have 2 more mowers with good engines and bad transmissions available cheap locally. So should be good to go with a cheap riding mower.

An no, that is not sludge in the pan, that is nearly 1/8" of metal filings

Previous owner ran dry on oil as he ran it with a loose oil filler.

Amazing it still ran.

 

[malcolm]

That is impressive damage. Very common with lawnmowers to run them without oil. We've got a Briggs and Stratton engine on ours which burns oil quite enthusiastically - need to check it every fill up.

Came cheap on eBay with other easilly sorted faults, but one of them was the fuel supply - if the fuel supply valve isn't closed after use the sump fills with petrol. Drained ours out when we first got hold of it and it was very runny.

Guess you've got a big lawn there. Ride on mowers are fantastic.

 

[shenion]

No, it is a tiny lawn. But most of lot is 80+ foot oak and hickory trees. Spend weeks cleaning leaves. Rider/bagger will help my back; raking and bagging leaves wears my sore back out fast.

I bought a used push mower for $30. Barely ran, found little clip on camshaft broken. Must buy new cam to replace at $87. Clip releases compression for easy starting. Removed it and it ran fine.

Was probably 10 year old when I got it. Used it for 10 years. Then one day it was like the car at the end of the Blues Brothers Movie. Handle mount pushed through deck. Then left front wheel folded over followed by rear wheel. Engine still ran like new

The guy I'm talking to on getting a second mower for parts says the failure is typical. Run low on oil, upper journal starves, counterbalance starts shaking wildly and rips fixed connecting rod out of block.

People say Briggs engines are crap. My experience is if maintained well, they last longer that what they are connected to. They could use a real oil pump though for better reliably (and low oil cutout.)

Off to pick up the parts mower...

 

[malcolm]

Mowers are funny though - full of clever but entertaining solutions to common engineering problems: if they did everything like the car manufacturers they'd be a mini-car and cost thousands.

I dislike Briggs and Stratton - sure they are well made but they are designed to need maintenance so will go wrong on a mower. Everyone else has got past the 1930s. I'd go Honda given the choice (and the money).

 

[shenion]

Other than changing oil, have needed no maintenance on mine. Biggest problem is carb gums up from old gas.

Yes, Honda is good, different market

11HP Honda - $740
Koler 16HP - $670
B&S OHV 13.5HP $500
Tecumseh 13.5HP - $390
Have seen the older flat head B&S for $300 new.

The Kohler engines are supposed to be good also, has real oil pump and external filter. Would be my choice as compromise between price/reliability.

 

[Hitch]

A place i worked had a genny welder with a Koler engine, i have never haerd anything as noisey

 

[scarecrow]

Honda is a very very good engine a old mechanic once told me lister made the best engine it would stay going till it fell apart and even then it would probably start first go

 

[peterd51]

Hi,

I have a Kohler 2-stroke on my hovercraft and I can't get the Tillotson carb adjusted right.

It's either leaks petrol out the bottom or there's not enough coming through to fire...

The engine itself looks good, I've stripped and rebuilt it, but I need to change the carb, possibly one from a 200 - 250cc motorcycle and hopefully I can get it running.

It'd be better in the long term to replace the engine with a 4-stroke once I've done some basic safety testing/running as it'd be a lot quieter.

Regards
Peter

 

[Lippyp]

I have a little Briggs motor on my push mower here, a bigger Tecumseh on my self propelled mower in France and a big 5.5hp Honda on my power scythe, the honda is the best starter of the lot, all four strokes. The 2 stroke motor on my Stihl brushcutter is pretty good too.