310 runs rough after rebuild

[Horse Lover 0]

Hi all

I just finished a rebuild on my 85 310-8 and this thing runs awful.

Put a new piston and rings in it,never messed with the valve timing. The points are set at .018 and when trying to raise the rpm i watch the timing light and it shuts off the spark completely. I tried a new condensor and coil with no luck.

Any ideas thanks Mike :thumbs:

[VinsRJ 721]

:thumbs:

There's a lot of good poeple here willing to help with your model and engine. :thumbs:

[WH nut 553]

Im assumig you have a K motor, If you have tried a new coil and condensor I would put a set of points in it. You have already covered everything else short of being a bad wire someplace. You could try hooking up a jumper wire to the postive side of the coil to battery and see how it runs. If it straightens out you know everything front the coil down is good and you need to start looking at wiring and switches.

[rmaynard 14,907]

:thumbs:

Let's back up here just a little. Before we get into why you are losing spark, you said that you just finished a rebuild where you replaced the piston and rings, but you did not mess with the valve timing.

Are you saying that you just put in a new piston and rings without having the cylinder bored, or at the least honed? Did you have it measured?

Why did you replace the piston? Were you having the stated problem before the "rebuild"?

[Horse Lover 0]

Yes its a K motor. Put a new set of points,and condensor on it before I ever started it (old set were burnt). I had to replace the piston and rings because of a cracked piston on the top ring land.

The motor has been replace with a new one not long ago cause there was no cylinder wear. The motor ran fine before I did this except for the low compression. I did notice before i did this rebuild that I was washing the motor off and got water in the flywheel cover and it died and took a while to get it started.

[WH nut 553]

Run a jumper and see how she runs, you have to start some place, and you stated you are losing spark so thats the place to start

[tommy3horse 3]

Hello Mike and

I am taking a stab...sounds like a wiring issue. Make sure the condenser is fully grounded on the engine tin and trace all ingition wiring if possible. I believe the K series points should be at .020. Also check/set valves to proper tolorences, check the Kohler manual for the proper settings because intake/exhaust are different.

Good luck...

Tom

:thumbs:

[Horse Lover 0]

I just ran a jumper wire to the battery and it didnt help. Traced the blk/yel battery feed from the the switch to the coil ,it was ok. Checked the coil it had 4.2ohm from + to - and 9200 ohm + to secondary. only thing left is the condensor and its new but it did come from autozone and we all know how there junk holds up. Guess i have to test it too by charging it up and zapping myself a few times lol. :thumbs:

[Horse Lover 0]

I tested the condenser with an ohm meter and it failed miserabley. So i guess i get to go to the toro dealer in town to get a good one (fingers crossed).

[WH nut 553]

New does not always mean good. If you still have the old one throw that back on and see how she does

[Horse Lover 0]

Went and got a new condensor today and walla she purrs like a kitten.

Now I get to find bearings for the deck.

Thanks guys for all your help. Greatly Appreciated

Michael

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[WH nut 553]

:thumbs: