1986 Craftsman LT12 38" trouble starting

tomekkplk

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So I'm fairly new to riding lawn mowers and bought my first one for $100 last spring, it was a 1986 Craftsman LT12/38 with a bag and the only thing it needed was a tire and battery. It served me well all year until the start of fall. It had a very tough time starting the last 3 times and started smoking pretty bad. I did change the oil before I used it and used fresh gas too. I'm not sure if the engine is just getting tired or it needs a tune up. (I've had bad luck with tecumseh engines in the past). Anybody experience the same or have an idea?
 

jp1961

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Hello,

You could try giving it a tuneup (new spark plug and air filter) to see if that helps the hard starting bit.

What color smoke, is it white/blue or black? White/blue means it's burning oil, then again it is a 1986 and quite old.

Replacing the piston rings is not that bad of a repair (just did it on a Honda walk behind mower).

Since you only paid 100 for it, I'd be willing to spend a few bucks on parts.

I've also seen on YouTube a blown head gasket will cause smoking real bad.

Regards

Jeff
 
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tomekkplk

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Thanks guys, I found the manual once online before when I bought it last year but every new search I did came up with the one model newer. I'll take a look at it soon again, just seemed odd one week it fires right up then the next week it gives me trouble. It doesn't smoke a lot, just on start up when it finally gets running. It gets pretty bad but then goes away completely and I'd like to keep this one for a while if I can. I'll update when I get a chance to work on it this weekend, thanks again.
 

bertsmobile1

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Check the oil level very carefully.
If the carb is flooding the fuel will flow into the cylinder & ultimately into the sump .
This both dilutes the oil and raises the oil level.

Running with too high an oil level will cause the engine to smoke badly.
Running with too thin oil will also cause the engine to smoke badly.
IT will also make the engine hard to start.

IT would be immensely helpful if you told us the actual engine numbers so we know exactly what you are dealing with.

Also "Difficulty Starting" is a useless term to help us to diagnose your problems.
Like walking into the doctors and saying "I feel sick"
The doctor can then take some readings ( pulse, temp etc ) but we are left with nothing but what you tell us.

Starting with a thorough tune up would be a good idea
The engine manual can be found here, it is a free download http://www.mymowerparts.com/pdf/
 
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