Kawasaki FD620D running poorly. Help?!

[Rock Doctor]

Wait a minute, something is tickling my memory here. Not sure if I want to read all your old posts, might be faster to just ask.
Have you checked your valves and Pushrods?
These 20hp Kawi Engines will Start beautifully, Idle like a dream, and run like a POS under load if you have skipped a Pushrod out from under a Rocker Arm, or bent a Pushrod.

RD

[gimmegreens336]

I got a new phone and waiting for the pictures I took to upload, it's giving me hell.

Here is my report:

Both plugs were loose, one I took out bare handed. The plug closest to the winch was wet with oil. The other plug seemed fine, if anything, gapped too small. (I'm buying the tool to measure gaps today) The valve cover on the firewall side has oil on it. Boo

As far as running goes:

I reset the idle-mix screw to manual specs, 1 3/4 counter-clockwise from seated. She idles like a champ. Good RPM, smooth shifts, choke not necessary to idle. I can give her wide open throttle when in neutral and she hesitates for a very brief moment to catch up, then she revs up good, I can hear it hit the governor and dial back just a notch. She runs awesome at wide open throttle in neutral. Sounds better than she's ever sounded. All signs point to GO....

until I shift into low gear and try to do some maneuvers.

At a low idle in low gear she seems to want to stay running, but as soon as I rev her up a bit she dies. Ran fine in neutral while tuning, even at high RPM, but not under load.

I anticipate some trash getting back in the carb, maybe plugging the main jet? Otherwise I could have botched the float when I reassembled. I set the float according to the manual but it required a sizeable adjustment to the tab holding the float plug/pin to make it sit parallel to the carb face like the manual recommended.



It sounds fantastic when running. It's never sounded so clean or idled so smooth. It's a shame it won't run! lol

[plott hound]

Damn you PH, you could have saved me a lot of typing if you posted that 5 min earlier

RD

yikes!your post is way more detailed.

[gimmegreens336]

Alright, I'll mess with her in a few hours when I get home. I hope it's flooding so it's an easy fix. If I were to lean the mixture and she continues to bog down under load I guess I'll take the carb back off and do another one-over.

[Rock Doctor]

yes,you need to tighten the screw to lean out the mixture.if you follow the tuning instructions in the manual to a tee,its very easy.turn the screw in till it starts to starve,then back out till it starts to flood.the middle setting of these 2 extremes is what you want.mine was damn near 1-3/4 turns out.

Damn you PH, you could have saved me a lot of typing if you posted that 5 min earlier

RD

[Rock Doctor]

There are no exact settings for a carb.On the body of the carb there will be a screw(usually brass).Screw it in clockwise til it lightly seats.Don't screw it in too tight as it will damage the tip.Then screw it out 1 1/2 turns.Start the machine.For the following adjustments go 1/4 turn at a time giving the machine about 15 seconds between each adjustment to react to the new setting.Start screwing the screw out(richer) 1/4 turn at a time til the engine starts to stumble from being too rich.Then counting the number of turns you make screw the screw back in 1/4 turn at a time(leaner) til the engine speeds up and dies from being too lean. Stop there.Now screw the screw back out half the number of turns you screwed it in.For example if you screwed it in 3 turns you would screw it back out 1 1/2 turns.It should be very close to being right.Adjust the idle and ride it.If need be fine tune the adjustment richer or leaner 1/4 turn at a time riding the machine between each adjustment.

RD

[plott hound]

yes,you need to tighten the screw to lean out the mixture.if you follow the tuning instructions in the manual to a tee,its very easy.turn the screw in till it starts to starve,then back out till it starts to flood.the middle setting of these 2 extremes is what you want.mine was damn near 1-3/4 turns out.

[gimmegreens336]

Thanks Spook - will do the spark plug test tonight.

RD - Yes, at first. When I put everything back together and put her in the field it seemed to run better the full opposite. I ended up settling on about 2 full turns from seated. Let me clarify, does the idle-mix screw regulate air or fuel? I assume fuel, so the more I loosen, the more fuel it allows. Is this right? So I have her opened up 2 full turns, the manual recommends 1 3/4 then tuning from there. If it is in fact flooding, I need to tighten the screw?

Thanks for keeping up.

[Rock Doctor]

Didn't you say you only backed your mixture screw out 1 turn?

RD

[spookum]

Tand run it HARD and then STOP and pull the spark plugs. Wet/ black spark plugs mean your running too rich (tak a picture of them, and the gurus here will help). Also, black smoke from the exhaust is a sighn of too rich.

[gimmegreens336]

Thanks Fred!

So I went out last night for a ride - and she didn't do well.. lol

Ok, first thing I noticed is that for the first time ever, she doesn't require choke or revs to start. I turn her over and she almost immediately starts a good low RPM idle.

I let her run for at least 10 minutes before I got in for a drive. She seems to do perfect at half-load or below. When I try and give her some work she likes to die. It takes a minute to start her back after turning off. Wonder if I'm flooding her? What are the symptoms of flooding?

Thanks!

[fmints]

I'm glad that you got her running again, and that you didn't come out of pocket too bad.

[gimmegreens336]

I'm a crappy thread host I should have been staking pics today but I was in the zone and in a hurry! On the phone right now but basically the throttle valve was right side down, but rotated 180 degrees the wrong way. It closes smoothly now. It idles with the correct RPM now. Crazy, the manual said install with numbers down but didn't specify the direction. I'm still excited to replace the springs, I massacred a few of them. I used a router to make a bigger groove in the throttle cable/handle assembly. It gets pulled back by the spring again. Took a few turns around the house today and she ran like a top. Couple more issues and still need to followup on everyone's recommendations, will check back!!

[Rock Doctor]

Good posts, good advise

RD

File? Slow down. You haven't tried the hammer and the torch yet...

Once you get your new springs on we'll be able to tell if you need to adjust your governor. (I hope not! That adjustment is super touchy)

Yeah, butterfly is a common name for the throttle valve. Butterfly is actually a type of valve and the choke is a butterfly valve too. The throttle valve in this carburetor is slightly off center (I think) and isn't supposed to be perfectly horizontal across the tube. If disconnected from all controls (so you can feel it) it should move open to close smoothly.

Assuming you mean the small bolt used in the clamp that clamps the governor arm to the governor shaft, that is how you adjust it. It is super touchy. A teensy bit goes a super long way. (look at the length of the arm - a small degree barely perceptible change at the shaft equates to obvious movement at the other end.)

Oh, let's wait for the new springs first...

And again I edit - it is so much easier to adjust this with the springs.

[JohnF]

Can I loosen the bolt attaching the governor arm to the pivot arm, rotate the governor arm clockwise slightly, then re-tighten? Will that hurt anything? It may or may not help.

Assuming you mean the small bolt used in the clamp that clamps the governor arm to the governor shaft, that is how you adjust it. It is super touchy. A teensy bit goes a super long way. (look at the length of the arm - a small degree barely perceptible change at the shaft equates to obvious movement at the other end.)

Oh, let's wait for the new springs first...

And again I edit - it is so much easier to adjust this with the springs.