81 spitfire issues

Technical topics related to machines powered by Kasasaki motors
81 spitfire
Posts: 36
Joined: Wed Feb 29, 2012 2:11 pm
Location: Nebraska

Re: 81 spitfire issues

Post by 81 spitfire »

I had a chance to look everything over this morning. I cleaned my extra carb again last night and put it back on the sled, I can now get it to run with the choke off. It seems to idle pretty well right now, but just dies out suddenly. It also is smoking a lot like it's burning too much oil. I have bypassed the tank for testing right now by running a different line directly to the fuel pump from a gravity fed fuel supply above the air box.

I removed the grommet that the carb attaches to the engine with and inspected it, I cannot see any type of cracking in it. I have 125 psi on both cylinders. I don't think that I am getting any air in around any of the gaskets/ seals on this motor, I just finished up putting all new gaskets and seals on it earlier in the week. The crank halves were cleaned before sealing and allowed two days inside to set up.

Could the cdi box be causing it to die out suddenly? It has died like this on me while it is idling as well as when I have it at 1/2 to 3/4 throttle.
JDT
Posts: 5561
Joined: Wed Nov 21, 2007 1:00 am
Real Name: Todd
Location: Milbank South Dakota

Re: 81 spitfire issues

Post by JDT »

Many have experienced similar issues due to a bad CDI box so you may wish to swap it out and see what happens.
Todd Schrupp

Milbank SD
81 spitfire
Posts: 36
Joined: Wed Feb 29, 2012 2:11 pm
Location: Nebraska

Re: 81 spitfire issues

Post by 81 spitfire »

I do not have an extra one to switch it out with, but have been considering purchasing a new one for some time now. I found some online for the 78-79 spitfires (part # MDI11-0204), but I'm not sure that this will work with my 80 with the kawasaki motor. They do have ones for trailfires (part # MDI11-0202) for 79-82. Would those work?

Here is the link for the site that I found them on
http://www.psep.biz/store/john_deere_sn ... _boxes.htm
JDT
Posts: 5561
Joined: Wed Nov 21, 2007 1:00 am
Real Name: Todd
Location: Milbank South Dakota

Re: 81 spitfire issues

Post by JDT »

My thinking is that a Kohler CDI would not work on your Kawwy.

But there are several Spitfire experts on here and one of them could tell you if the Trailfire box is the same as the Spitfire.
Todd Schrupp

Milbank SD
81 spitfire
Posts: 36
Joined: Wed Feb 29, 2012 2:11 pm
Location: Nebraska

Re: 81 spitfire issues

Post by 81 spitfire »

I replaced the cdi box and the sled seems to sound like it is running stronger and doesn't die out like it is loosing spark when giving it throttle off of idle. It seems to be idling stronger now, but I have come across a new problem. It wants to bog down when I get it to about half to three quarter speed.

I am going to pull the carb off again and clean it, but what else should I be looking for? Also, it is smoking quite a bit and after running for a couple of minutes, the snow under the exhaust pipe is black. Is it possible one of the rings didn't seat properly and I am getting incomplete combustion?

Thanks
JDT
Posts: 5561
Joined: Wed Nov 21, 2007 1:00 am
Real Name: Todd
Location: Milbank South Dakota

Re: 81 spitfire issues

Post by JDT »

Could be rings. Did you do a compression test?

Is the fuel old or mixed with to much oil?

Plugged exhuast, clutch problems, wrong spark plugs, bad bearings in the drive.... the list can get long.

Got to check everything from front to back.
Todd Schrupp

Milbank SD
81 spitfire
Posts: 36
Joined: Wed Feb 29, 2012 2:11 pm
Location: Nebraska

Re: 81 spitfire issues

Post by 81 spitfire »

I had done a compression test and had 125 on both sides, new gas, and was not running it with the belt on when the engine was bogging down. However, I won't be running this engine again for a while as the pto side piston is now in a bunch of pieces and need to do a complete overhaul and find replacement parts. I found what looked like the remains of a nut in the cylinder that I believe caused my newest problem. I will post pictures as soon as I can figure it out. Thanks again for all the help
JDT
Posts: 5561
Joined: Wed Nov 21, 2007 1:00 am
Real Name: Todd
Location: Milbank South Dakota

Re: 81 spitfire issues

Post by JDT »

Yikes! That is not good.

Sorry to hear about this.
Todd Schrupp

Milbank SD
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