1997 30hp will not idle

[alanfox55]

SN 0G465407 It will not run below 2500 RPM. I cleaned the carb with carb cleaner then ran a small wire through all the holes.Looked through the little holes with a flash light and did see that the idle pickup tube was a little clogged but it was good after using the wire. Then I blew more cleaner through everything to make sure gas could flow freely. I also replaced all gaskets and the idle mixture screw and spring.Then I did a link and sync.It started right up and did sound better while running but still would not idle below 2500 RPM.My service manual is suggesting I have bad reeds but I wanted to get some opinions before I started on that. Oh and I did check the float level but did not replace the inlet needle.Thanks for any help.

 

[alanfox55]

Come on guys help me out here please.

 

[Brooky]

A healthy dose of seafoam is worth a shot.

 

[alanfox55]

OK thanks

 

[Guest]

Did you touch the idle screw? Did it idle normaly before you took the carb off? Check your manual for idle screw settings

 

[Sea Rider]

Alan some issues :

-It's a 2 stroke 2 cylinder carbed engine, right ?
-As you have not made an open water outing, assume up to now, can't know for sure if engine was working spotless before.
-One thing is testing on muffs, barrel at idel, fast idle, other story is at open waters under load throughout the whole throttle range.
-What worked top at idle under first cond doesn't mean will work ok under second cond. Different stories.
-What's " will not run under 2500 revs", be more specific. Engine misses, dies ? How does it behaves ?
-Reed valves don't come bad next day, have never changed a pair in my entire boating life. Are delicate parts you don't mess with.
-If engine has issues under 2500 revs with faulty reed valves will have same issues throughout the whole throttle range.
-Could be an electrical issue, ignition coil gone bad. Had some cases in which IC gave missing issues from idle to 1/3 throttle and none from 1/3 to full throttle. New IC cured the horse.

Have learned that before investing huge money buying electrical instruments, is way better investing in spare IC. CD and swapping each untill the culprit is found. Way faster to troubleshoot and cure, less costly than sending engine to a shop to have same parts replaced along extra hand labor bill, but that's me.

Happy Boating

 

[alanfox55]

Thanks Sea Rider and Weimed.I took the carb off and cleaned it because of the problem but it didn't cure it.Yes it's a 2 cyl 2 stroke.I bought the motor 2 years ago and have started it a few times on muffs before this time. I had only run it for short periods it never getting up to operating temps so I assumed needing high idle while cold was normal. It has always started right up with no issues as it does now but this time,still running it on muffs,I ran it up to good and warm but it would still die when I dropped the RPM's below 2500.The other time I ran it I didn't have a tach ether so really didn't know what it was running at.The motor has always ran fine with the RPM's up and runs even better after rebuilding the carb.The way it dies is just as if it needed to be on fast idle to warm up but you didn't do it so the RPM's slowly go down until it dies.Looking in my service manual it says "Unable to reduce engine RPM to slow idle" which is a perfect description of my problem and the only possible it gives is bad reeds. Replacing the reeds is pretty simple and cheap on my motor so I expect I will be doing that as soon as I get the parts. Thanks for your thoughts.

 

[Sea Rider]

When horse dies at 2500 rpm, is it easy to start again, or need to wait for some munutes to start it back again ? If so, could be an electrical issue, component heats, shorts and shuts engine down, starts back again when cold to miss again and so on eternally.

As said before, one thing is testing an engine with no load at all or min load if shifting lever into gear on barrel muffs and different story while at sea, lake, river whatever at load pushing a boat throughout the whole throttle range.

For testing engines on barrels, muffs, need a special prop to do so throughout the whole throttle range.You should not poke metal wires through carb holes, could damage internal fuel passages. The question we all ask at the inflatable forum is : When will Titanic see open waters ?

Happy Boating

 

[Guest]

You still have not answered my question. Did you ensure your idle screw is configured correctly? If it is screwed out to much it will die when you try to idle. Can you start your outboard at idle? You need to diag the problem before running out and buying parts. I been following the repair forum for over 2 years and have not heard of anyone changing reeds. I would take a long hard look at the carb and how it works

 

[Sea Rider]

Idle corresponds to the low speed carb circuit, cam doesn't actuate carb roller, it's ralenti time, carb sucks on its own. 2500 rpm is way passing idle, corresponds to the fast speed circuit, cam is pushing carb roller. That engine must be tested on open waters, go for a wot run as if stealling the combo and see what happens, then troubleshoot with patience.

You need to change reed valves only if they are deformed, not closing flat on port or missaligned, to check that cond will need to remove reed valve assembly and have a look. I doubt having those issues. But could have something stuck there ?

Happy Boating

 

[alanfox55]

To answer Weimed question after cleaning the carb I did a link and sync on the motor.About the wire I only used a few strands of copper wire from a small electrical wire and only ran it through a few times to make sure the holes are clear. One issue about running it on the lake is I can't put it in gear at such a high rpm and I can't get it into gear at a normal idle so don't know what to do there.One thing that I did not do was put in a new inlet needle on the float.I couldn't punch the float pin out to do that but it looked fine and the float level was correct. That could be the problem so maybe I should go back and do that.I'll update when I do.

 

[Sea Rider]

Turn upside down carb, float must be parallel and even to side carb edge, blow ext fuel tube with mouth. If needle valve seats correctly air won't pass to carb's bowl, if passes needle is kaput, will need to be replaced. OTOH if needle doesn't seat spot on will flood intake and combustion chambers, which is not your case. How do you know timing and carb sync are well adjusted, have a service manual ? Do you achieve full opened carb butterfly at max timing advance specified for that engine when at full throttle ? What's the factory stated timing advance in deg ? ?

Happy Boating

 

[alanfox55]

Yes I do have a factory service manual for my engine.I measured the float height and it was on and the needle was working properly. I synced and linked according to the manuals instructions and assume it's on because it starts right up and runs good as long as it's at 2500 rpm or above though I try to keep it below 3000 because I don't feel comfortable letting it rev above that. There is a big sticker near the timing marks that says this engine does not need to be timed only synced and linked correctly. I have thought about that and believe it must be able to get out of timing and needs to be adjusted at times and it does say what that timing is.At this point I'm thinking that's not the problem and don't have a timing light so I'm ruling it out for the time being. One thing I haven't checked out is the fuel pump but then again I have to believe it's good or it wouldn't be able to start and run so well...I will check it though.

 

[Guest]

i got stuck out today with same issue. lucky i was with a buddy he towed be back. I checked fuel pump and its all good. have the carb off the ouboard gonna clean it. I did notice the tank does not cave in with vent closed. all pointing to carb or fuel line. Popped open the the carb it looks brand new. Going to buy new fuel line.

 

[alanfox55]

Sorry you had the problem,that's one reason I plan to always have a trolling motor with me. I put in a new inlet needle yesterday.The old one had a plastic tip that was worn down some and the float adjustment was to high. I had been thinking that replacing the inlet needle and making sure the float adjustment was spot on was the only things I hadn't done when I rebuilt it.I bought a float adjustment scale that allowed me to get the float right. I remembered I had a small hobby vise and that made it possible to get the float pin out so I could change the needle which had been a problem and why I hadn't changed it the first time. I went back and did all this because after thinking about it I realized that my spark plugs always seemed to be wet and maybe the motor dieing was being caused by flooding.I'm going to run it today,maybe I finally fixed it.

I've had a problem with my tank fuel line too. I cut it shorter then it wouldn't work.I found that I had cut off some kind of valve in the hose that the bulb used to work properly so I replaced the bulb and that fixed it. Good luck.

 

[Sea Rider]

Is the needle seat replaceable ? If, so change it too. Those 2 buddies must work hand in hand together.

Happy Boating

 

[Guest]

Sorry you had the problem,that's one reason I plan to always have a trolling motor with me. I put in a new inlet needle yesterday.The old one had a plastic tip that was worn down some and the float adjustment was to high. I had been thinking that replacing the inlet needle and making sure the float adjustment was spot on was the only things I hadn't done when I rebuilt it.I bought a float adjustment scale that allowed me to get the float right. I remembered I had a small hobby vise and that made it possible to get the float pin out so I could change the needle which had been a problem and why I hadn't changed it the first time. I went back and did all this because after thinking about it I realized that my spark plugs always seemed to be wet and maybe the motor dieing was being caused by flooding.I'm going to run it today,maybe I finally fixed it.

I've had a problem with my tank fuel line too. I cut it shorter then it wouldn't work.I found that I had cut off some kind of valve in the hose that the bulb used to work properly so I replaced the bulb and that fixed it. Good luck.

Did you find the issue? i replaced the fuel line and still have same issue. I narrowed it down to spark. I recommend you do a spark test. If its not a healthy blue spark then thats the issue. I ordered a new ignition coil and will see if that will fix it. If that does not fix spark then will work on the control box. I am really hopeful this will fix my motor.

 

[alanfox55]

Sea Rider the seat is not replaceable as nothing came in my rebuild kit and there's nothing in my manual so unless tells me for sure it is I'm going to assume it is not.I did however squirt carb cleaner through it and it was flowing good.

 

[alanfox55]

I have not had a chance to run it yet as we are dealing with a tropical storm around here right now. I did purchase a spark tester and will test spark if my issue has not been resolved.

 

[Sea Rider]

Will a auto spark tester measure spark strenght or just indicate there's a spark going on. If the latter you'll need an adjustable spark tester, the ones you can adjust the electrodes distance neerer or farther from each other to measure spark strenght. The farther the spark will jump the better..

Happy Boating