DF 2.5 questions

[keakar]

yes the main jet (the big screw) is whats used for full throttle

the pms is the idle jet, the needle jets are used for mid throttle, and full throttle is the main jet

[JRDIII]

Update:

I heard from the shop today, and it wasn't good news. They got the motor cleaned up, changed the oil and plug, but the problem still persisted. So they took apart the carb and cleaned it thoroughly including all the jets. He told me they also "back-flowed" the jets to see if that would dislodge anything. Nothing, and when they put it back together the problem was still there. He said it's possible there is something blocking one of the jets, but the only way to know for sure would be to stick something in there and they won't do that because of the risk of causing damage. He said it's also possible it's a manufacturing flaw, which is rare but does happen. They are going to try cleaning it one more time and if that doesn't work it's time to call Suzuki.

[Symore]

JRDIII thanks for the update. This is what I was worried about and I am sure glad I am not alone. It might be the the wrong jet size like Keabar was saying and thats what I am thinking too. The shop should have different size jets and I would go for the next size up for the main jet. I am not working on mine yet because it is still winterized but in a few weeks I will start it and take it from there. Please keep us posted with any new updates and thank you again for your post.

[Symore]

Ok for 2007 motors and later it has a main jet #64 with jet #66 being the next size up and showing as optional so that is where I would start. That should give it give it more fuel as the thottle is opened up. I am not positive but I am thinking this is worth a try.

[Symore]

Also if going up in size with the main makes it worse than it might need to be sized down if the problem is it is getting to much gas causing the problem. The main would need to go down to size #62. That is why Suzuki list the main jet sizes # 66 & #62 as optional. Hopefully this with solve the problem with these motors. Could also be they put the wrong jet in at the factory thinking it was going to be put on a different size motor. Keabar suggested the same carb might be used for different size motors. The correct size from the factory would be main #64.

[Symore]

JRDIII do you have any new updates on your motor?

[JRDIII]

Not really. The shop went ahead and ordered a new carb from Suzuki, under the warranty. I called them today to ask what was taking so long, so they called Suzuki and Suzuki told them the carb has been shipped. Should be here Thursday or Friday. Assuming they replace the carb and it works, it won't really help pinpoint what the problem was. Maybe I can get them to do an autopsy on the old carb.

[Symore]

It is good news that they are replacing the carburator. But it might not solve what the problem was like you said. I hope this works for you, If it dosent solve the problem I will order the #66 main jet so I will have it ready when I run off the fogging oil. I will have to follow up on maybe it is a jetting issue. It is still a little too cold here to work on it here. Thanks for the update.

[Symore]

JRDIII read this from another site

Suzuki or me. Who's right? 2.5hp

[JRDIII]

I actually saw that thread during a Google search a couple of weeks ago. Doesn't seem to bode well for my prospects of getting this resolved. I'm going to make darn sure the motor is working properly before it leaves the shop. I'm convinced it's a jet problem, and not a problem with fuel. I think the factory jet setting is too small, but then I'm no expert. Hopefully the new carb will do the trick.

[keakar]

i read the link and W O W , holy crap it sounds like a messed up design for sure but to run good when dry the not after it gets gas sitting in it?

not to mention the dying situation is a big red flag of more issues

cant believe they sell untested motors because this was obviously not run through trial tests or the issues would have been found.

[JRDIII]

Update:

The marine shop called Friday and said I could pick up the motor. I had been hounding them all week about what was taking so long, and I told them I had planned to go fishing this weekend in my new boat. So when I got there Friday afternoon they said I could take it with me but they needed me to bring it back as soon as I could. Huh? They said they installed the new carb and tuned it, but that Suzuki still wanted them to make one last adjustment they hadn't had time to do. They said it would run fine for my fishing trip and that they had worked double time to get it back to me before the weekend so I could go fishing, but I still needed to bring it back.

I wish they had told me before I drove up there. I used the fishing outing as a way to put some pressure on them, but I'd have cancelled it to save myself a trip. Oh, well. I appreciate the effort, but I really didn't want to have to drive all the way back up there to drop it off, and then again to pick it up. Nice guys, though.

When I got there Friday they had the motor on a stand with the prop in a tank. It started right up. The first thing I noticed was that it was idling a good bit higher than when I had brought it in. The shop manager said he thought the company I bought it from never tested or adjusted it before shipping. I figured that to be the case because it came in a box that looked like it had not been opened since leaving Japan. He said the idle was way too low when I brought it in, and the idle is actually supposed to be set pretty high.

When I asked the manager why I had to bring it back, he said Suzuki wants them to make an adjustment to the pilot jet. When I asked him to be more specific he said they want him to replace the pilot jet with a slightly larger one. So I asked if that would be a 66, but he said, no, they want him to replace the size 32 with a 33. So, Symore, I don't know if this is the same jet you were talking about, but the factory setting appears to be different from what you mentioned. He definitely called it the "pilot" jet. He said Suzuki knows that the factory jet may be a bit lean, but they set it the way they do for emissions reasons. Suzuki told him there's no recall but they are tweaking the jets on a case-by-case, as-needed basis.

Anyway, the throttle seemed to work fine now with the new carb, both in neutral and in gear. No problem accelerating. So, I paid for the oil they had replaced (the new carb was warranty) and took it with me. Today, I put it on my brand new Zodiac Zoom SIB and took it out on the 350-acre lake where I like to fish. It was my first time using the new boat, so it wasn't until I got the boat in the water that I realized the transom is really low. When I put the motor on, the anti-cavitation plate was a good three or four inches under water. The motor pushed the boat pretty well, much better than it pushed my old Sea Eagle. But the transom definitely needs a shim, and I think the 2.5 will run even better if I can get the prop a little higher in the water. It never seemed to max out on rpm, even at full throttle. Full throttle sounded to me like three-quarters throttle. I think it was because the prop was so low it was putting more load on it. I'll work on that. Great day on the water, anyway, and in the end I'm glad I got my fishing trip in after all.

I'll try to take the motor back to the shop sometime this week, and I'll update when I get it back with the new jet.

[Symore]

JRDIII that is great news, I am glad its running right for you now. Getting back to the jetting issue. There are more than one jet in your carb. My guess is Suzuki is aware of this problem and the replacement carb now has the #66 main jet in it. The pilot jet(controls the fuel at idle to about 1/4 throttle)is #32 and the next size up would be #34 not #33. I will start with the pilot jet and see what affect it has on idle to 1/4 throttle. It might overlap the main enough to give it enough fuel. Thank you for this information about your motor and when I work on replacing my jet or jets I will post my results.This thread will help others in understanding why this motor runs bad out of the box. So my theory is a #66 main jet and or a #34 pilot jet is the solution. Again this is just my theory and I will try it and post my results. Another guess I have about you bringing it back to the shop is so they can do a spark plug reading to see if it is running rich enough. Good luck to you with your new boat and now a nice running motor,lol.

[Symore]

Follow up

After calling different Suzuki marinas I gave up going that route. Called a Suzuki atv center and they were able to order the jets for me. While waiting for the jets to come in I removed the carb and took the two jets out and everything appeared clean. Now on the one side of the carb there are two tin plugs, the top one being smaller than the bottom one. I removed these plugs to find a idle mixing screw in the top one. The bottom one is a chamber for gas to go through and should not be removed unless it needs to be cleaned out. I could not find a replacement plug on the internet. What I did was find a stainless steel screw with a head that find in the hole and cut the head of the screw off. I than used some jb weld on the screw head to seal in the hole so gas would not leak out. Works but it is now permanently sealed. Installed a #66 main and #34 pilot jet in the carb and installed the carb back on the motor. Started the motor and let it warm up than adjusted the idle mixture screw. It idled best at 2 turns out and is within the perimeters of the pilot jet so it did need the bigger jet. Also I put some rtv silicone in the hole over the screw after it was adjusted to seal it. Now for the results of the jets. I ran it in a 5 gallon bucket and it still hesitates when chopping the throttle real fast but opening the throttle normally it runs real smooth through the rpms. This still needs to be tested under a load in gear but so far it is showing much improvement and still has the original spark plug in it. So if it doesn't foul the new spark plug under load it appears to be a much improved running motor.

[JonnyMo]

Suzuki DF2.5

I bought a small trimaran sailboat, a Multi23, and it came with a used 2009 Suzuki DF2.5 outboard with the Walbro LMJ carburetor.

It was always easy to start, and run at half or full throttle, but it would die easily at idle, unless I played with the choke. And it always needed the choke to restart it, even when warm.

I first put in a new spark plug. And that helped a little. Then I see the discussions about everyone have problems and trying bigger jets and so I ordered them online from Brown's Point Marine service.

Suzuki Outboard DF 2.5 Fig. 5 - Carburetor

I ended up ordering the following:

3-6 09491-66005 ▪ Main Jet #66
15-3 09492-34004 ▪ Pilot Jet #34
2-2 13236-97J20 ▪ Main Nozzle

Plus the necessary gaskets.

The order arrived in about a week and I just got it all installed and put back together.

The engine now starts right up, and after a few minutes of warm up, I'm able to push the choke off and it just sits there happily idling. The idle set screw is just barely opening up the throttle valve. The manual says idle is 1900 RPM +/- 100 rpm. I don't have a way to measure it. But my ear says it's close.

I can even engage it into gear at idle and it doesn't die. If I slowly increase the throttle, the engine rev's nicely, but if I suddenly open it up at idle, it dies. For now I can live with that.

It was a straight forward project. Here is what I learned. First, take pictures with your digital camera/cell phone of every step before you take things apart. Just in case you don't remember what goes where later.

The carburetor diagram from the Browns Point Suzuki site is correct. The one from the Walbro site doesn't match the carburetor on my engine.

It was easy to remove the carb from the engine. Just release the choke link at the carb, and unscrew the fitting holding the end of the throttle cable.

The two bolts holding the air intake box and the carb to the engine comes off with a 8mm socket with a small extension.

The fuel line easily came off as did the crankcase ventilation tube. The carb will leak gas when you remove it. Be prepared with a large rag/towel or something to catch the gas in.

The 10mm bolt, at the bottom of the carb, which accesses the main jet and main nozzle easily came off . A 7/32" slotted screwdriver bit worked unscrewing the main jet. And the main nozzle sits on top of the main jet and just fell out.

It was harder to get to the pilot jet. To take the top of the carb off I had to remove the choke plate and choke shaft. Then the four screws holding the top came off.

I thought that I'd have to remove the throttle valve, but I didn't have to. At first I didn't know that and I found that the throttle valve does not come out easily. It's brass, soft with a special beveled edge. In addition, the screw that holds it on has some special dry threadlock so it doesn't vibrate loose and get sucked into the engine cylinder. I ended up using Loctite blue threadlocker to put the screw back in. The loctite should be gas resistant when cured.

The pilot jet sits under a chrome plated screw. Take the screw out and you'll see the pilot jet about an inch down the hole.

A regular screwdriver will NOT get pilot jet out. I ended up buying a metric screwdriver that is 0.8mm thick, 4mm wide and 100mm long (Wera 05032003002) and it was a perfect fit. I have a very good tool store nearby in Seattle ($9.29 @ Hardwicks). The Amazon one below is the exact same tool.

Amazon.com: Wera 05032003002 Kraftform Stainless 3335 Stainless Steel Slotted Screwdriver, Lasertip, 4mm Head, 4" Blade Length: Industrial & Scientific

Once the jets were out, I cleaned everything in carb cleaner and made sure to spray all of the orifices well. I was surprised how much gunk came out of the carb, even though it looked clean.

I used all new gaskets. I had to cut out the old carb bowl gasket and cut off the one on the bottom of the bowl.

I reassembled it all, using loctite on the choke and throttle valve screws. To speed curing of the loctite, I heated the carb with a heat lamp until it was hot to the touch.

Reinstalling it was a snap. Adjusted the throttle cable so there was no tension when the throttle was off, and just barely turned the throttle idle screw to open the throttle valve. I put the outboard back on the boat, then turned the fuel on and opened the gas tank vent. Choke out and it started on the first pull!!!

So far so good. I'll get the boat out and motor around for a while. Then I'll pull the spark plug and see what it looks like. It should be a good indicator of what my fuel/air mix is doing. I may put the #64 original main jet back in if I don't like the response going instantly to full throttle.

As others have speculated, I think Suzuki tuned the engine to run lean so it would pass emission standards. But the engine doesn't like it, especially at low rpm's. So I think the new jets have helped. Or maybe it was just the carb cleaning.

BTW, I live in Seattle, at sea level and it's a cool climate. This fix may not work for your local conditions.

Hope this helps others with problems with their Suzuki DF2.5 outboards.

Jon