[nicksorg]

Hey all. Over the past couple of weekends, I've seen a good amount of smoke on start-up. Engine seems to run strong once oil burns off.

Back in 2010 I pulled the engine and had the cylinder bored and a valve job done by a machine shop. I assembled piston and rings. I estimate I have about 70 hours on it since rebuild. I was careful to ensure the ring gaps were not aligned together.

I'm going to do some troubleshooting over next couple of days. Since this motor has a compression release, how do I go about doing a compression/leakdown test test correctly?

 

[nicksorg]

Forgot to mention that I run SAE 30 oil

 

[jcronk69]

Is it just a puff on start up you are seeing?
That is pretty normal for a Kohler.
Are you having to top off often?

 

[nicksorg]

I just put in 12 oz to get it to the top of the fill line. I changed the plug and mounted my 49 blower to do the first snow. It ran well.

When I was done the throttle went full and wouldn't throttle down. I finally figured out the screws fell off the carb throttle plate. The pieces ended up in the exhaust so I pulled the head to check for damage. Looks like I got lucky as the cylinder isn't scored. The breather looked to be installed correctly when I removed it. There was a bunch of oil in that compartment. I'm wondering if the rings ever set from the rebuild or if I installed them wrong.

Since I need this for winter, I'll likely fix carb, clean up combustion chamber, install a new head gasket, clean up breather area and monitor oil consumption.

 

[nicksorg]

Now I'm wondering now that I have the top half off of the motor, if I should just pull it out and check the piston ring clearances and if they are installed correctly. Looking for opinions.
Thanks
Nick

 

[dr_evil]

To do that correctly, you'd have to run a hone over the cylinder bore to re-establish a fresh cross-hatch on the cylinder, and replace the rod cap bolts since the new Kohler rods have one time use only rod bolts.

I'd just replace all the gaskets you've taken off like the head gasket, breather cover gaskets, and try running it again.

 

[mikeduwe]

Yuck. That's a LOT of buildup for only 4 years. Something was done wrong with the rebuild.

 

[nicksorg]

Thanks guys. I have to detach the motor from the transmission to put a new screen on so I may as well pull it and do it right.

 

[akaothermick]

That certainly looks about normal for a flat head motor of 4 years, personally that would not cause any concern to me, I see no oil washout to suggest that the rings did not seat, carbon build up is average, nothing unusual there. Good color on the exhaust valve, and intake nice and clean. Head gasket looks like it had no leaks. OK motor to me.

 

[nicksorg]

If I bring piston up TDC, is it safe to clean off it with a wire brush or scraper or do you risk the carbon particles falling into the bore and causing problems?

 

[akaothermick]

Yes, lightly wire brush to clean, then move the piston down, wipe the bore, slightly grease the bore move the piston up then down, continue doing this as required till cleaned up, don't aggressively clean the piston, some probably wont come loose,