Same 4HP Suzuki Different troubles

[hedghawg]

Lets see how this goes... I Got a 2 stroke 4hp suzuki, it is a real clean motor with a few minor problems. So I rebuilt the carb and Put it back on. It will work but only at 1/3 throttle and up. I have the idle screw set all the way up and I still have to twist over the throttle to keep it going. it runs smooth, water is going through the pump as it should. the choke at the 1/2 open will allow it to idle but it idles roughly and sounds like it is occasionally missing. HELP!

 

[Yepblaze]

Re: Same 4HP Suzuki Different troubles

Pull the carb back off and finish the carb repairs with a thourough clearing of the idle circuit. If unable to get idle circuit cleared, consider carb replacement with a new one.

 

[hedghawg]

Re: Same 4HP Suzuki Different troubles

Which passage is the idle circuit?

 

[jim dozier]

Re: Same 4HP Suzuki Different troubles

This is where you need a manual. The carbs are all different for different models and years. In general the main or high speed jet is located more or less in the center of the carb, probably sticking up through your carb bowl. The main jet on most carbs are fixed but some of the smaller engines may have adjustable high speed jets. The idle jets are usually somewhere else and are almost always adjustable with a screw that may meter air or may meter fuel. This is important because if you unscrew it it might let in more air (lean) or more fuel (rich). When cleaning a carb you have to dismantle them and remove the jets and clean them in solvent and blow them out with compressed air and then reset the float heights and idle circuit adjustment. It sounds as though your idle circuits are still dirty and/or out of adjustment.

 

[DJ]

Re: Same 4HP Suzuki Different troubles

Take a good look at the carb. float level.

 

[hedghawg]

Re: Same 4HP Suzuki Different troubles

The Manual isn't here yet. All I have is a schematic that kinda resembles the mikuni carb I have. The holidays throw off ups...

 

[hedghawg]

Re: Same 4HP Suzuki Different troubles

It sat in the carb solution most of friday night/saturday and saturday evening I took it out and put it back together after I blew all the passages out with air. (Canned air)There wasn't a whole lot to it about eight parts total.<br />and there was a little sediment in the bottom uf the bucket of solution but nothing else. I set the idle screw at 1 1/2 turns out and now that the float was mentioned,I'll go back and check that. As simple as it was I still feel like somthing got missed.

 

[jim dozier]

Re: Same 4HP Suzuki Different troubles

Did you remove the idle mixture screw before you soaked the carb? It is best to remove the jets and or mixture screws and clean them and then blow them out then reinstall them. As Djohns said don't forget the float valve which after removing and cleaning as above needs to be set to a specified measurement.

 

[hedghawg]

Re: Same 4HP Suzuki Different troubles

Yep, I did. The whole thing was apart in a little bucket of the carb cleaner and blown dry by a can of air after inspecting the soaked parts for build up. Like I said it was about 8 pieces total. The carb kit was a float, an o-ring, mounting gasket, float needle and the needle oring gasket for the bottom of the fuel bowl and that was it. The parts after cleaning shined like new money and had no build up of any kind on them. It runs at mid to full throttle and runs smoothly but it won't idle unless the choke is at 1/2 closed. I have checked, and rechecked everything. the float level is a mystery because the kit had an exploded view of the carburetor and how it goes back together. No additional specs on it which bothers me because it was a genuine Suzuki kit.

 

[jim dozier]

Re: Same 4HP Suzuki Different troubles

Shawn, give the year and model number of your 4hp and I will check my manual when I get home and see if I can come up with the proper float level setting and base idle mixture setting. Your symptoms are very definitely those of a lean idle mixture, we just need to find out why. In the mean time check for any air leaks you may have missed.

 

[hedghawg]

Re: Same 4HP Suzuki Different troubles

here it is... 00402-461467

 

[jim dozier]

Re: Same 4HP Suzuki Different troubles

Shawn,<br />That should be a 1994 DT4. Clymer manual says float adjustment is 0.47-0.55 inches. Flip carb upside down and measure from bowl seal bottom to the bottom of the float. Take the float off to bend the tab otherwise you'll damage the float needle. Idle air screw adjustment is 1 to 1.5 turns out from lightly seated. The screw meters air so when you unscrew it you lean out the idle. Screw it in to richen it. Based upon your description I would try starting it at 1 turn out. Hope this helps.<br />Jim