Lakesailor
Well-Known Member
Sod All.
The only fix is to strip and blow out. Possibly even soak in a tin of carb cleaner.
Suzuki DF 2.5 running issues
- Thread starter Iain C
- Start date
The only fix is to strip and blow out. Possibly even soak in a tin of carb cleaner.
Slowtack
Well-Known Member
Cooling water flow is quite poor on any of these I have seen . Apparently some (early?) models were recalled and had the thermostat removed! Some had a 6 blade impeller, others only a 4 blade which did not help. Same applies to Johnson 2.5hp.
MagicIsland
Well-Known Member
Not sure if they have upgraded the cooling but mine is really powerful, when going backwards if the water jet hits the transom I get soaked
Got mine June 2011, it does say let it idle for 5min before putting in gear in the manual, this is my first outboard so don't know if thats unusual ???
Carduelis
Well-Known Member
Stale petrol?
Leaving petrol in the engine for a long period can gum up the carb jets. Always a good idea to drain the fuel lines and carb over winter.
Sometimes even a squirt of carb cleaner won't shift the gum and the only solution is to get it ultrasonically cleaned. O/b shops and lawnmower repair places usually have the kit.
Leaving petrol in the engine for a long period can gum up the carb jets. Always a good idea to drain the fuel lines and carb over winter.
Sometimes even a squirt of carb cleaner won't shift the gum and the only solution is to get it ultrasonically cleaned. O/b shops and lawnmower repair places usually have the kit.
Lakesailor
Well-Known Member
Surely not. A good blow through at 160psi has always achieved a thorough cleaning for me.
aslabend
Well-Known Member
I've had one for 4 years now, used regularly maybe an hour or more a week over the season. Usually it starts first time and runs really cleanly but after a while it starts to not idle very well and if that happens, I take the carb off, take the float bowl apart and give everything a good spray with aerosol carb cleaner and it runs fine again. Never found the spark plug to be a problem. Cooling water is injected into the exhaust so usually only a mist comes out the exhaust tell tales (enough to wet your fingers when motoring to check it's working) but has never been an issue. The carb seems to be the weak link on mine as it's tiddley and just seems to get gummed up with crud really easily but this is hardly unique to small outboards I would say.
JonnyMo
New Member
I saw the same discussion on the Suzuki Outboard discussion boards. And I have the same problem with my Suzuki DF2.5 outboard.
http://www.suzukioutboardforum.com/suzuki-outboard-parts-forum/3166-df-2-5-questions.html
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.
http://store.brownspoint.com/df2_5-01/fig005.asp
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.
http://www.amazon.com/Wera-05032003002-Kraftform-Stainless-Screwdriver/dp/B001O4LXDE
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.
Hope this helps others with problems with their Suzuki DF2.5 outboards.
Jon
http://www.suzukioutboardforum.com/suzuki-outboard-parts-forum/3166-df-2-5-questions.html
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.
http://store.brownspoint.com/df2_5-01/fig005.asp
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.
http://www.amazon.com/Wera-05032003002-Kraftform-Stainless-Screwdriver/dp/B001O4LXDE
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.
Hope this helps others with problems with their Suzuki DF2.5 outboards.
Jon
solentyachtshare.net
New Member
I have to thank Jon, I did just as explained above, whipped the carb off, removed the choke, undid the four screws on the top plate, obtained the correct screw driver, unscrewed the pilot jet, poked a piece of wire through the blocked jet (you know where the brake cables on your bike fray at the end, a single strand of that wire) blew through it, reassembled in reverse order.
Whay Hey, a perfectly ticking over Suzuki 2.5 in less than 30 mins at a cost of £4.00 for the screwdriver (B+Q).
Thanks again Jon.
Whay Hey, a perfectly ticking over Suzuki 2.5 in less than 30 mins at a cost of £4.00 for the screwdriver (B+Q).
Thanks again Jon.
BelleSerene
Well-Known Member
Yes, it does - and almost certainly it's this, not the idle-speed screw, that is the problem.
The 'Primary Mixture Screw' feeds fuel to the engine at idle before the throttle is opened. Once the butterfly opens, the PMS loses vacuum and no more fuel is pulled through it.
Suzuki set the engines to run lean at idle speed in order to meet emissions targets. Trouble is, because these small engines aren't fitted with an accelerator pump, increasing the throttle quickly makes the mixture extra-lean and they can stall before the new higher speed feeds sufficient fuel through the main nozzle.
View attachment 60926
The Primary Mixture Screw is hidden under a think alloy anti-tamper cap, which you have to drill out. Then with a thin screwdriver you can control the primary mixture screw. Quick job: turn the PMS 1/4 or 1/2 a turn anticlockwise (ie opening it). Slower job: warm up the engine, then screw the PMS right in while counting the revolutions until it stops. That was your reference setting. Now unscrew it to where it started, restart the engine and screw it in until the engine 'hunts'. Count the screw revolutions from that point to the end stop. Then do the same again, screwing it OUT until the engine 'hunts'. Count the screw revolutions from that point to the end stop. The point between those two reference points will be perfect.
That's the main problem, and it seems that it's a really common one on this model, caused by Suzuki deliberately setting the idle mix too lean.
I gather that you can also improve the performance of the engine by increasing the size of the carburettor's Main Jet and optionally the Pilot Jet. This is only worth doing if you're not satisfied with the effect of the correction above. I hear (unconfirmed) that Suzuki may now be fitting a larger ('#66') main jet on the engine than they did on the early models. There's a diagram and parts list here [ http://www.boats.net/parts/search/Suzuki/Outboard/2010/DF2.5/CARBURETOR/parts.html ] and the changes proposed are to increase the Pilot Jet from #32 to #34 and the Main Jet from #64 to #66.
When I buried my 2.5 Honda air-cooled dinghy outboard at sea on the 3m contour off Herm, I replaced it with this Suzuki DF2.5. It's a lot quieter and about as light. Annoying that it needs to be kept one way up, and that one way is sitting on its throttle arm.
Hey, this post is only 4 1/2 years too late for the OP - he's probably replaced his by now too!
RichardS
N/A
Indeed, but perhaps better late than never!
One thing confuses me though. As soon as the anti-tamper cap is removed, why not just gently screw in the mixture screw until it is fully home whilst counting the turns to get the reference setting? I've never thought about doing it any differently.
Richard
fredrussell
Well-Known Member
Tam Lin
Well-Known Member
Worked for me as I said on one of the many threads on this subject. Thanks again Fred!
BelleSerene
Well-Known Member
Indeed, but perhaps better late than never!
One thing confuses me though. As soon as the anti-tamper cap is removed, why not just gently screw in the mixture screw until it is fully home whilst counting the turns to get the reference setting? I've never thought about doing it any differently.
Richard
Yes, I agree Richard.
Constantin
New Member
Hi everybody! I hope you can help me with a DF 2.5 problem unrelated to carb issues. Part no. 7 from drive shaft housing (union water inspection), the exhaust main water jet, sometimes gets blocked by debris. If you dont spot it on time it can destroy the engine. I was wondering if there is a more practical solution to this.... i assume that modifying the part (making the exit hole bigger so debris dont get stuck there) is not a solution since it will change the parameters of the engine... I appreciate any advice. Thank you !