Can I adjust the clearance on these valves?

[Mick Oz]

I did try the old finger on the plug hole method, there is some air forced out but it's not enough to say one way or the other. The compression tester that I have on hand is for the large Diesel engines that used to get serviced here.
I ordered a general purpose one, but it has not arrived yet.

 

[reynoldston]

How did you test for spark. Your spark should jump a good 1/4 inch to run that engine. I also have a tool to test that. If you don't have this tool you can make one by taking a old spark and give it a 1/4 spark gap.

 

[Mick Oz]

Thanks for that, I certainly have the old spark plugs that I removed. 1/4 of an inch is a large gap for any spark, is that what you mean?

 

[ILENGINE]

The command engines use a capacitor discharge ignition. It puts out a lot of voltage. The actually Kohler tester looks like a spark plug that you removed the side electrode from and then recessed the center electrode down inside the ceramic about 60 thousands.

 

[reynoldston]

Thanks for that, I certainly have the old spark plugs that I removed. 1/4 of an inch is a large gap for any spark, is that what you mean?

Yes this is what I mean. You will need that much spark for that engine to run. Now if we are talking about a Kohler Command it has two coils so test both of them. As ILENGINE said they do make a tool for this, but a old spark plug with a wide gap dose the same job. You can buy a tester from most parts store and all it is a spark plug with a clamp on the side of it and the ground electrode is missing. You can buy them for less then 5 dollars over here. They also sell a spark tester with a light but that wouldn't tell you if you have a weak coil.

 

[Mick Oz]

Thank you, I will test it and let you know what result I get.

 

[bertsmobile1]

A cheap & nasty tester is a 1/4" ring of tube slipped over the insulator on the plug then put the cap on .
This forces the spark to jump from the cap to the plug with the plug laying on the engine.
Compression increases the electrical resistance of air so a spark that looks good outside the engine may not happen inside an engine.

 

[reynoldston]

.

Compression increases the electrical resistance of air so a spark that looks good outside the engine may not happen inside an engine.

Very true, This is where the light tester comes into play. It tells you if the spark plug is any good or not under compression. Something we did in the earlier years clean the spark plugs and test them under compression in a machine that did that. Plugs are cheap just replace them.

 

[Mick Oz]

Now that is a very handy test to know, I've been swapped to some night shifts this week so won't get at the machine till next week. I will let you know how I progress.

 

[bertsmobile1]

There are a couple of tools that I could not work without.
One is my inline spark tester, I have 1/2 dozen of them cause a I do on site servicing and customers always want to buy mine when they see it being used.
There are a lot out there but the neon tube ones work the best as the orange/red light is easy to see but a blue /white spark is not so easy.
For testing the strength there is another one that slips over the plug and has a moving contact which you move out till the engine stops.
There are a lot of cheap Chinese copies of this on the web, if you don't pay better than $ 50 for one it will be SHOCKING experience

The best one of all is the Colortune which is a spark plug with a glass window so you can see not only the spark jump the gap but also the colour of the flame inside the engine.
Poor mans Co/Co2 meter.