Kawasaki Doesn't always wanna run

[jakesmurray]

I have a weird problem.
It is a FB460V engine 12.5 HP.
All summer the engine would start right up every week.
Now, it is getting into the 30s at night. When I go to start it during the day, it doesn't want to start. It kind of sputters, but never starts. Here is the weird part: if I put a brand new spark plug in it, it will fire right up. However, the next day, nothing, unless I put a brand new plug in it then it will start. Here is what I know:
-fuel system is clean and is supplying sufficient fuel
-fuel is fresh
-Correct oil level
- carb is clean
It runs great once it is running.
I am leaning towards a compression problem, since it ran fine in hot weather. I do not have a tester, but plan on getting one soon to check it.
The engine was made in 1985, and to my knowledge has never been rebuilt. It has a lot of use on it.
Do you know what the compression should be for this engine, and what compression tester do you recommend?
Thank you in advance

 

[chance123]

It sounds like your spk plg is fouling out. Next time, with the old spk plg still in, try starting without using the choke.

 

[Rivets]

You might want to try to borrow or rent a compression tester from your car mechanic or where you buy your small engine parts. If you have worked with them in the past, they may be willing to help you out. I would not purchase one unless you figure on using it at least once a month or just starting in working on units.

 

[jakesmurray]

I have tried no choke with old plug. It won't start without a brand new one in it.

I do work on engines, especially during the summer, so I may buy a tester.

 

[Rivets]

If that is the case I would buy the best one I could afford. Make sure that the hose is stiff and Gage is easy to read. A hose that flexes, will expand under pressure and give you a false reading. If you a afford it, I would recommend purchasing a cylinder leakage tester instead. It is far more useful and will give you a better diagnosis of where the problem are. Just an old wrench monkeys opinion.

 

[jakesmurray]

If that is the case I would buy the best one I could afford. Make sure that the hose is stiff and Gage is easy to read. A hose that flexes, will expand under pressure and give you a false reading. If you a afford it, I would recommend purchasing a cylinder leakage tester instead. It is far more useful and will give you a better diagnosis of where the problem are. Just an old wrench monkeys opinion.

Ok thanks for the information. I appreciate it :thumbsup:

 

[chance123]

I have tried no choke with old plug. It won't start without a brand new one in it.

I do work on engines, especially during the summer, so I may buy a tester.

I find it interesting that replacing the spark plug "always" allows it to start. Usually, a spk plg shows the health of an engine. When it doesn't start, and you R&R the spark plg, is the old one oiley (as in black oil)? Is it wet (as in fuel)?

 

[jakesmurray]

I find it interesting that replacing the spark plug "always" allows it to start. Usually, a spk plg shows the health of an engine. When it doesn't start, and you R&R the spark plg, is the old one oiley (as in black oil)? Is it wet (as in fuel)?

I know, a very odd problem.

Yes when I pull the old one, it is very black and very wet with gas. It looks like it has been there for 10 years, even though it has no more than an hour on it. :confused2:

 

[chance123]

I know, a very odd problem.

Yes when I pull the old one, it is very black and very wet with gas. It looks like it has been there for 10 years, even though it has no more than an hour on it. :confused2:

OK! Now we're getting to the root of the problem. You "might" have a collapsed oil ring on that cylinder. To get you by for a while, try increasing the spark plug gap on your next new spk plg. .035 or .040

 

[jakesmurray]

Ok so you are thinking oil is getting past the rings?
I will try that gap next time.
Thanks