Can't prime/start after sitting

[bashr52]

I spent the last week prepping my boat for the holiday weekend after removing it from storage. Specs are: 1979 75 horse lower end, 1978 85 horse top end. 140 psi on all 3 cylinders, rebuilt carbs, rebuilt fuel pump, (diphragm, gaskets, and check valves), all new lines, CCM "Sport" reeds, all new intake gaskets, timing at 30 degrees, 8mm plug wires, and an Allison electronic ignition system out of my street car. All work was just completed within the last week.

This issue: Pump the primer bulb once, and it goes rock hard. I can hardly squeeze it again it is so firm. Gas get through the pump and fills my filter. I can not get it to prime the engine however. Cranking with or without choke, or throttle setting makes no difference. If I put even a tiny dribble of gas or short shot of starter fluid into the intake, it will fire up first turn and run fine. Once it has started I can go to a spot, shut down, fish for 1/2 hour or more, hit the key without choke, and it fires right off. If I let it sit for a few hours however, I have to repeat the same sequence again.

Other information: I did the link-and-sync per the sticky. I tried to throw a quick tune on it while on the muffs in the dirveway. Carbs all adjusted in nicely, set the idle at around 1200 RPMS, and it was running good. I found that although it idled strong, as soon as I dropped it in gear it would die and not want to restart. I ended up turning the mixture screws out about 1 turn a piece, and although it smoked a bit at idle, it would stay running in gear. I did have to adjust the idle screw in almost all the way to get it to sit around 800 RPM in gear at idle. This eliminated my fast idle warm up, as now when I pull out the knob and take it to fast idle, the distributor just barely moves (increases RPMS only about 100-150 RPMS's). When I adjusted the carbs again on the water, at their happy spot, neutral idle went up to over 2000 PRM, and when I adjusted it back down, it would die in gear again.

Planning a week long fising trip the first week of July, so I'd really like to get this thing running correctly....

 

[pnwboat]

Re: Can't prime/start after sitting

Sounds like your choke isn't working correctly. Are the choke plates closing all the way on both carburetors? They choke plates should be pretty much all the way closed when the choke is engaged. You can adjust how much they close by moving the choke solenoid in the bracket that holds it in place.

 

[bashr52]

Re: Can't prime/start after sitting

Yes I adjusted the choke plates so the worked all together when I re-assembled the carbs. They work smoothly and close fully.

 

[pnwboat]

Re: Can't prime/start after sitting

I wonder if the choke is actually engaging when you turn the key and push in? It's easy to listen for the "click" when you push in on the key without turning it. But when you engage the starter, it's pretty hard to listen for the click. Maybe a bad ignition switch that is disengaging the choke when you turn the key?

On a side note, I have been running a set of aftermarket composite reeds in my 1988 125HP motor for the last 4 years. When the motor is cold, I do have to engage the choke longer than what I would consider "normal" to get it to fire. Once the motor is warm, I just barely touch the key without choke and it fires right up.

 

[bashr52]

Re: Can't prime/start after sitting

Yes I can hear/see the chokes closing. Besides the hard to start when cold issue, I'm also concerned about the tuneability/idle issue I am having...... Did you have to work on fine tuning your engine with the composite reeds?

 

[foodfisher]

Re: Can't prime/start after sitting

Try cleaning the fuel recirculation system and clean the sparkplugs.

 

[bashr52]

Re: Can't prime/start after sitting

Try cleaning the fuel recirculation system and clean the sparkplugs.

I forgot to add plugs to the list, those are new as well. As far as the fuel recirculation system This engine has carbs.

 

[pnwboat]

Re: Can't prime/start after sitting

It sure sounds like the motor is too lean after it sits for a while and fires right up after dribbling some gas or a shot of starter fluid into it. Starter fluid by the way is not the best choice for 2-stoke motors. It can wash away any lubricant on the bearings if you use too much. Could the floats be set too low?

Maybe the CCM Sport reeds are not suited to your motor for your application. Maybe the standard reeds are what you need. When you installed the reeds did you take a close look at them to make sure that they were all laying perfectly flat against the reed cage?

I know on my original set up, there was a curved metal plate, I think it was called the reed stop...not sure about that, but when I installed the composite reeds, I did not install that part (reed stop).

Yes I had to just tweak the idle mixture like maybe a quarter to half a turn when I installed the composite reeds....but I don't remember whether it was leaner or richer. I believe it was leaner but it's been a while so I don't remember exactly. Anyways, right now they are set to just a tad more than 1 turn out from lightly seated. Like 1 1/16 of a turn out.

 

[bashr52]

Re: Can't prime/start after sitting

I ended up re-setting mine to 1 turn out, and that allowed it to idle in gear, and all seemed to work out ok after that (except for some smoke at idle). It likes to run leaner with the new reeds. I was approaching the max recommended 3/4 out turn and it still wanted more. That would cause it to die with a load however.

On the reeds, I did verify they were all sitting flat, as I ran into that issue on my jetski when I went to boyeseen on it.

(I forgot to mention the starting fluid thing, I know about the fuel wash issue on 2 strokes . I managed to find some fluid that was lubricant based, thats advertised for 2 strokes).

Floats may be low? I re-installed them the way them came out, only with the new needles and springs.

 

[pnwboat]

Re: Can't prime/start after sitting

This applies to the later model Force motors, so I'm not 100% sure it applies to your motor, but I'd think it would be similar if you have the Tillotson or Walbro carburetors. To set the float level, remove the carburetor, remove the fuel bowl and turn the carburetor upside down. The body of the float should sit parallel to the casting of the body of the carburetor.



To adjust the float level, bend the tab that pushes against the needle valve.

If the end of the float sits too far away from the casting, then it is set too low (Remember, you're looking at the carb upside down) which means the bowl will not up to the proper level. If the end of the float is too close to the casting then the float is set too high which may result in flooding and gas overflowing out of the metered vent hole on the side of the carburetor.

If your floats were set correctly then that would eliminate that as a possibility.

 

[bashr52]

Re: Can't prime/start after sitting

Hmm something to check out..... I know they are not flooding out the vent hole, but if they were set high and flooding into the engine, that would explain why it likes a lean mixture setting to compensate......

How much should the distributor advance when in fast-idle mode? Like I said above, due to my high idle speed setting, mine just barely moves.

 

[bashr52]

Re: Can't prime/start after sitting

Well in between rain storms yesterday I was able to work on the boat some. I reset and verified the chokes were all closing, and started completely over on the link-and-sync. I did have to hold the chokes longer than normal, but it did start and run on its own. Carbs seemd to settle in at about 1 turn out, that gave me a good hole shot and smooth running through all RPM ranges. I am only turning about 4800 RPM at WOT, but it runs strong so I'm not super concerned about that. The big test will be after it sits for a week if it will start on its own again, but all seems to be well now!