DF25 V Twin problems

[Riomon]

I am having a low idle problem with my 2013 DF25 V Twin. The carb was rebuilt six months ago with new jets, o-ring gaskets, filters,etc. It will not idle unless I block one of the two air intake holes on the side of the carb. Then it runs rich , but does run. This motor has less than 100 hours on it. Could it be something else on the motor that is causing this ?
I have no dealer warranty as the motor was shipped to Guatemala from the U.S. . I live on the Rio Dulce in Guatemala and my boat is my car as there are no roads to my house. I'd really like to fix this problem and have the motor running correctly. Qualified Suzuki mechanics are not really available on the Rio even though there are hundreds of boats here. Typical third world situation ! Thanks for any help.

[Solarman]

df25, 2013, idling problems

Do you have a manual for the motor?
Does your motor have an iac (idle air control) valve? Parts list says yes.
Ill check parts listing for your motor. If yes, (iac valve), try cleaning that valve and opening, have read posts they can cause idling issues.
Another possibility, if that doesn't help, check clean the map sensor, and opening. I am not as familiar with the df models, but hope one of the will help you. Someone more familiar with the 4's should chime in soon.
Good luck. Let us know what you find.

[Riomon]

Yes I have a service manual.Correct me if I'm wrong, but wouldn't the IAC and map sensor be on a fuel injected motor ? This motor is carbureted. Looking through the service manual I see no mention of either.

[Solarman]

df25, 2013, carb'd,

Yes you're right... I completely overlooked your mentioning it was carb'd. My mistake.
In that case, try turning the air mixture screws in. if you have multiple carbs, then both screws should be the same adjustment. If your manual tells you 1.5 turns open, then set them all the same. Count the number of turns to close them till lightly seated, then back out to what your manual tells you. If you still need less air, turn all in equally .125 (1/8th), no more than .25 turns than book tells you. Turning the screws in, turns the air from those holes you put your fingers over off more. Yes, this makes it run richer, but you will have to find that sweet spot between rich and lean that your motor likes, and should be right where your book tells you.
Good luck, let us know how it's doing.

[Riomon]

Well today I went through everything again. Everything is clean.
Now I'm also getting a really rough running motor at RPM's higher than 3000.
Does anyone think this could be a problem in the valve train ? Maybe a stuck valve or ?????

[Riomon]

Same problems, different day ! I have given this carb an ultrasonic cleaning and can not get it to run unless the fuel/air mixture screw is almost all the way out. It will then idle, but stall at any higher rpm's .
I also took it to Guatemala City (4 hours away) and the Suzuki "mechanics" could not come up with a solution other than buying a new carb.

I wish someone with a lot of knowledge of this motor would chime in to this thread.

Thanks for any help.......

[bklake]

Have you checked the valve adjustment? A valve that is out of adjustment could cause these problems.

I've had my carb apart a few times and it runs fine. I would suspect an incorrect gasket somewhere that is letting air bypass the normal route. Make sure the jet under the rubber cap is clean. I over looked it and it was causing me similar problems.

[Riomon]

bklake, thanks for the reply. I will check the valves this week. you would think that they would be fine with less than 100 hours on the motor, but nothing would surprise me at this point........

anyone else have any ideas ?

[Moonlighter]

Just on the valve adjustment, the dealer is supposed to check and adjust valves at the 20 hour service, but many of them ignore this.

The valve adjustment is done via shims that you will have to get from Suzuki, and I seem to recall that a special tool is required. So may be easier to get the dealer to do this check and adjustment for you.

[ziphd1]

df25 v-twin issues

hi i'm new to this an need some help. first are the any recalls by suzuki in the df25 v-twin? mine is a 2011 and it has 5 hrs on it. i just bought it and have only run it with the flushing hose attached. when i bought it. it seemed to run fine in gear forward reverse up to 3/4 throttle and had it a wot for a few seconds. the issues as of now is when it's in neutral and i try to rev throttle it breaks up. i'm guessing rev limiter or is it suppose to do this. i'm not cranking it hard just a quick little snap. if i go real slow with throttle it will let me bring rpms up a little before it breaks up. i've also read on this site that running at wot for a period causes the rev limiter to kick in this seams to be an on going issue with the df25 v-twin since the onset of this outboard. also read some have fixed it by going up to a higher pitched prop. feel like i just got screwed wth wish i knew before buy it, what a dub i usually do my home work better.. please help

[bklake]

My Suzuki DF25 manual is for the 2006 model year. It shows that the valves are adjusted via a double nut arrangement. Cold engine. .003-.007 mm. Piston at top dead center of compression stroke. Loosen lock nut while holding pivot nut. Turn pivot nut to bring valve clearance to within specification. Tighten lock nut to 11N-m 8 lb-ft. That is straight from the factory manual. And this is all there is to it. Very simple.

It seems to me that valve clearance changes the most in the first hours, then it doesn't change much. If you can set the valves on an air cooled VW, you are set. I think those are common in your part of the world. Hope this helps.

[bklake]

ziphd1. In Neutral, the rev limiter keeps it right at 3000 RPM. This is perfectly normal. Many people think they can tell exactly how many revs their engine is turning. This motor is very smooth at most RPMs and is tricky. I can not judge the engine speed by sound at all on my engine. I have a Suzuki Tachometer, cross checked by a Tiny-Tach. 4000 to 6000 sounds all the same to me. You will never know if you are hitting the upper rev limiter unless you have a tach. You might get an engine alarm but I've never "tested" that aspect of the alarm system.

[Riomon]

Well, my problem has been fixed with a new $400.00 carb.
But I still can't figure out why all the cleaning and rebuilding of the old carb failed......

[Romain]

Df25 carburetor issue

Hi,
I have experienced the same issue: engine not working without choke...I dismantled the carburetor at least 5 times and finaly fixed it by cleanning under pressure with a chemical normaly used for diesel oil nozzle removal.
I'll try to post more details on it latter.