Generator: problems problems problems

[salem1987]

Hope this is ok in this section.

Just bringing my Suzuki SE1200 generator back to life to power some tyre warmers this year.

Cleaned the carb, spark plug and fresh fuel. Got it fired up but it died after 10 seconds and now just backfires flames out of the carb when i pull it over. Cleaned and set the carb up again along with cleaning the plug but having the same issue.


I'm thinking valve clearances and maybe a sheared woodruff key. I hope not the latter! Going to check these next when i can.

These generators are awful to get parts for too, it seems.

Any other suggestions?

[Nemo]

Could be a timing issue, is it using points?

Did you fiddle with the mixture screw when you cleaned the carb?

Spark plug correct type? Looked at the colour of it to see if it's running lean?
____________________
Previously owned: Kawasaki KH125, Suzuki GP125, Suzuki GX 125, Honda CB125 TDC '83, Honda ntv 600, Kawasaki ER5, Kawasaki ZZR600, Aprilia RSV 1000 Mille
Now own: Ducati 848 evo

[Taught2BCauti...]

Flames coming out of the carb can only mean one thing - the inlet valve is open when the spark plug fires.

This can happen it the ignition timing is 180° out.
____________________
Honda Varadero XL125(V8)
www.TheFutureIsHere.eu

[salem1987]

Carb is set up as it was when the genny ran perfect for a few years so that should be ok.

The plug is fairly black actually but nothing to crazy. Had the head off and everything looks ok. Valves and springs look to be fine.

Timing wise the rotor looks to be all ok and the timing is correct i believe. Its not on points either.

One thing i've just considered and i don't know if its even possible but could the engine be turning over backwards from the pull start being incorrect? Ive had this happen on 2 strokes when the timing is too advanced/retarded and it gave the bike a reverse gear ha ha.

There a puffs of fuel vapour coming out of the carb when you try start it. The carb is almost acting as the exhaust, the sound of the engine firing is coming straight through it.

[Taught2BCauti...]

It sounds like the inlet valve is still open whilst the piston is travelling upwards, so either the valve is not seating properly (check gaps), a chunk of it has burnt off (do a compression test), or the ignition timing is out.

If you can get hold of an ignition timing strobe, remove the spark plug and spin the engine over to see what the camshaft is doing.

When the spark plug fires, the lobe of the inlet cam should be furthest away from the valve, and about 90° behind the exhaust cam.

If the engine was turning over backwards and the timing was correct, the piston would be going downwards the wrong way on the compression stroke - the inlet valve should still be shut.
____________________
Honda Varadero XL125(V8)
www.TheFutureIsHere.eu