B & S 8 HP Failure

[H2GURU]

Trying to "save" any Bitogers with this engine. Had this on a TORO 8-32 *17 years) rider mower and always took excellent *or so I thought} care of it. Changed oil half way through season and at end, always ran dry of fuel, kept all parts lubed etc. However I had been adjusting the high speed flow at carb bowl last few seasons and had the result of leaning it out. Kept getting worse, but thought it would last till seasons end, but she died on me. It appears that the head got loose over time and the valve got cooked.
1.Does ANYONE here torque their small engine head?
2 Is there any hope for this engine or should I s**** it, the rest of the machine is pretty good.

 

[Dark Jedi]

17 years is a long time for an engine. if the deck is still good. might just get a replacement engine. next time dont fiddle with the carbs lol.

could always take it to a small engine repair shop. to see if the engine can be rebuiilt. but most these places charge an arm and leg in labor.

 

[80caprice]

Its just the valve? you can replace valves and seats.....

As for torque on the side valves.... I have always done it criss cross till they were good and tight.... maybe a turn after the bolts get snug..... never a problem.... ever.

 

[Hirev]

quote:

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1.Does ANYONE here torque their small engine head?

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Yes

quote:

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2 Is there any hope for this engine or should I s**** it, the rest of the machine is pretty good.

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It kind of depends on how many parts it needs. Could be just the valves and some lapping would fix it. Or it could need much more. Only way to know is tear into it and do some inspection. At 17 years old you may want to look up some prices on a new motor if it needs much.

 

[Brett Miller]

It's very possible it has a loose valve seat. Peen the seat with a punch, lap the valves and set the clearance.

 

[doitmyself]

Brett beat me to the punch. I had happen exactly what he described on a 8 HP B & S horizontal shaft older engine.

The valve seat comes loose and the engine gets insufficient compression and other bad things. The mechanic re-seated the valve seats and peened them in to secure them.