Kawasaki FD620D running poorly. Help?!

[gimmegreens336]

Machine is a 1997 with 180 hours.

Just had a blast at Busco with all of those folks, but my motor didn't wanna do any work! Spent most the time fiddling and gimping around.

Members lewis and fmints helped at Busco to diagnose a bit of the problem. I was sputtering loudly and losing 50% of power or more for one of the rides. We got back to camp and found a clean main fuel filter, then found another fuel filter right below the carb and removed it (may have been a little dirty).

Pulled the line and showed that the fuel pump was pumping good.

Removed the spark plugs and the first was black but shaped right. (Plugs less than 15 hours old) Then removed the second and it burnt the tip completely off. There was a small hole where the tip used to be. Bingo we thought, replaced the plug and we were off for a ride.

Machine ran good for another 45 minutes or so then decided it wanted to randomly turn off. This is where we sit now. It will start when it's cold for just a little bit, then turn off again. Any time I try to give it gas it turns off. I can't say for sure whether it will run at idle or not, it never has... lol.. It's always idled especially low, I have to turn it off when sitting still, otherwise keep it revved to stay on.

I plan on removing the plug again this evening to see if it fouled again. Originally the plug fouled made it sputter, now it's just not staying running.

Also, the FD620D manual says to run regular gasoline. My family always runs 93 in their small motors so I've been running 93. Maybe switch to 87? I'm not sure how to diagnose a motor as "running rich" but it seemed there was a little "oil"esque residue on the inside of the air filter if that matters.

I absolutely will replace all the fuel line this week or weekend just to take that possibility off the table.

Always wanted to get more familiar with motor mechanics so I guess here's my shot?



PS: This thread will be picture (and video if need-be) heavy, I just wanted to go ahead and explain everything while I'm sitting here doing nothing at work... lol

[eddieb1965]

Are you sure the tip burned off?I worked on a Briggs that wouldnt start very good and had little power.One plugs electrode was gone,and that cyl. had no compression.Pulled the head and the electrode was caught(welded to valve seat),not letting the valve close completely.If the tip actually burned off,you may have burned a hole in the piston also.I have seen this happen when the wrong heat range plugs were used.Just a couple of things you may want to check.

[Dan67]

Make sure you are running the correct spark plugs.. I copied this from my conquest notes.. maybe this will help you some.

When replacing spark plugs on the Kawasaki FD620D Liquid Cooled OHV Engine,
it is extremely important to pay strict attention to the specification number of the
engine being serviced. All Conquest vehicles manufactured prior to vehicle serial
number CB17857 require spark plug part number 92070-2072. Vehicles produced
from CB17857 with a specification number of HS12 or later require spark plug
number 92070-2112.

Kawasaki has made changes to the Cylinder Heads, Head composition, & spark plugs
of the FD620D. The newer spark plugs are longer and will cause damage if used in
an older spec. engine.

[fmints]

Are you sure the tip burned off?I worked on a Briggs that wouldnt start very good and had little power.One plugs electrode was gone,and that cyl. had no compression.Pulled the head and the electrode was caught(welded to valve seat),not letting the valve close completely.If the tip actually burned off,you may have burned a hole in the piston also.I have seen this happen when the wrong heat range plugs were used.Just a couple of things you may want to check.

yes, this is true!!!!

maybe 93 octane is a little to much for the "kaw",, 93 has less oil or lead in the fuel, thus making hotter temps or as some say, a bigger explosion at combustion. I would try a new set of spark plugs with some regular 87 or 89 gasoline ( whatever the book calls for) and see what she does. Your ignition coil may be faulty and putting out too much spark to the spark plug, so reading the manual to find the resistance rating (i think that's what it's called) or whatever method to test the ignition coil for serviceability would be next. I would also check the oil for fuel (usually you can smell the fuel in the oil, and the oil will be thinner and not as slick)

Dont get down Gimmegreen,, with your machine being a 1997, there is no telling how it was used by the previous owner. I remember a statement you made at Busco, " I want to get more mechanically inclined with my machine", now the argo is granting your wish!! This happens to us all. I've pulled my engine in my hustler 11 times and I'll only had it 9 months. what makes this hobby so cool,, the tears, grease and sweat that we face and the satisfaction we get when we fix our machines is priceless.

[coosaridgerider]

I would run a compression test to make sure there is no issues there.If you don't have one you can get a loaner from autozone.

[gimmegreens336]

eddie dan fred and coos - thanks for the input!

I'm not sure when I will have time to do this work but I'm looking forward to it!

Eddie - I will check the valves and pistons, specifically on the side it "burnt off" or whatever.

Dan - Thanks for the plug information. I may have been able to avoid this problem to begin with if I were running the correct plugs. When I got the machine I just took whatever plugs were in the machine to the auto part store and got another set of those. It's possible the previous owner ran the wrong plugs as well.

Fred - Yeah the machine is def granting my wish!! lol... I will check the ignition coil and you reminded me of a big lapse on my part... I've never even changed the oil in her!! I've done plugs, air filter, every grease fitting, trans fluid, idle chain service and some other things - but never oil! Jeez - oil will make the top of the list too.

coos - didn't know I could get a loaner tool to check compression. Will eventually get to this too! Thanks!

[fmints]

if and when you do the compression test, do both wet and dry.

Note: compression test only test the piston rings,,,, get into the manual and make sure your psi per cylinder dead on what the book states.

a leak down test, test how sealed the engine is, whelther the intake or exhaust valve strings are weak, or you have a bad gasket or bad rings, but ,, It pinpoints the problem. The Youtube is "OUR FRIEND"!!

MAN I LOVE THIS SITE,,,,, INFO COMING FROM EVERYWHERE!!!!!

[lewis]

Remember that in 1997 gas was gas....no ethonol was in it, now about all fuel has a 10% mix in the fuel. The high test 93 is suppose to be (e) free. The fuel injection system on my Avenger runs like fudge with the (e) mix. So i only run 93 Octane fuel.

Lewis

[lewis]

if and when you do the compression test, do both wet and dry.

Note: compression test only test the piston rings,,,, get into the manual and make sure your psi per cylinder dead on what the book states.

a leak down test, test how sealed the engine is, whelther the intake or exhaust valve strings are weak, or you have a bad gasket or bad rings, but ,, It pinpoints the problem. The Youtube is "OUR FRIEND"!!

MAN I LOVE THIS SITE,,,,, INFO COMING FROM EVERYWHERE!!!!!

This machine has very few hours on it for being a 97. I think there are two issues with the machine. The idle circuit is probably full of particles from the fuel line that is discentrigrating and needs replaced and clean the carb. The second i would do as Fred said and check compression. The valves on this model will get stickey causing it to pop back through the carb. I don't thing the engine is worn out because the machine looks like it has been taken care of pretty well. These engines are very good engines and 180 hours is nothing for these units. I would hate to think how many hours Rock Doctor has on his machines under some of the most harsh conditions.

The spark plug was not hitting the cylinder on either side because the tab over was still in place but the electrode on the back cyclinder was completly gone. Heat range may be off but the plug was not hitting the cylinder but they were loose enough that i turned it by hand. The filter was a little oily and may have become impregnated with oil making it burn rich. Hope this helps.

[gimmegreens336]

You the man Lewis! I am in the middle of trying to talk John (the little brown guy that was with me) and his wife into letting me borrow their enclosed garage for a few weeks. They don't park vehicles in it! I'd love to have an area protected from the elements for a little while when I break her down.

I'm going to replace all of the fuel line this evening if all goes well. I see information all over the place talking about fuel line degradation so that'll be a good start before getting into the complicated things.

Lewis, I like your point about no (e) in gasoline when my manual was written in 1997. What do you other fellas think? I've always ran 93 in my lawn mowers and other small engines, but only because that's what my family does. Is it possible that the 87 recommendation in the manual is because gasoline was different in 1997?

Thanks to all of you guys! I'm pumped to learn more about this!