'99 40hp VRO very easily flooded on cold start....

[ahicks]

Guys,
Looking for ideas on how to remedy this problem. It seems like if I use the choke while cranking the engine, even for a second, the engine gets a bucket of fuel dumped into it, without even a single pop or attempt to start.

The ONLY way I'm able to start it (and then not totally reliable, maybe 90%) is to squeeze the primer bulb until it's hard, turn the key on, engage choke for just a second, THEN crank. If it's going to start, it will do so immediately.

Once flooded, the plugs will need to removed, dried with compressed air, and reinstalled. Once this is done, and the starting procedure repeated, then it will start.

What I've done-
VRO "stuff" removed/disabled
New Fuel Pump
Carbs cleaned (twice)
New fuel line w/ends

The engine runs perfectly (from idle to WOT) once started. Flooding issue occurs ONLY at cold start - after not running for a few days.

Is there supposed to be a restrictor or orifice in the primer system that restricts the fuel flow when engaged? If so, where is it? I've had outboards for over 40 years, and never had an issue so challenging. I had this one for a couple of years when this crap started, so I know it's not normal.

What am I missing? Thoughts?

Thanks, -Al

 

[boobie]

Do a compression test on it. Then a spark test using an open air gap spark tester set at 7/16 ".

 

[fireman57]

Every engine seems to have it's own starting quirks. Mine sounds like yours so what I do is put my throttle about 1/4 and crank it. If it hits a little and doesn't start I barely bump the primer while cranking.. It will sometimes die after that but will start quickly on the next turn with no primer. If you have a warmup lever try putting it up and not using the primer until it hits and then only a quick bump. make sure that the rod going into your primer solenoid isn't sticking.

 

[ahicks]

boobie - No compression tester or open air gap tester available, so asking for your thoughts behind these tests? Both plugs are the same color when removed, and the engine seems to be making plenty of power when running. Will put the pontoon "on top" easily at about 4000rpm (top is 5500 or so), which is the first for any other 40 I've owned. If you think it might be justified, I'm willing to invest in both tools. They'd be cheaper than another engine, which is something I'm close to doing to rid myself of this issue. A man can only take so much frustration, ya know?

fireman57- Ideas appreciated. I feel whatever this issue is it's something stupid, and just the right idea from somebody will jog this old brain into one of those light bulb turns on ideas that fixes it.

The throttle control is set up for a "high idle" by pulling out on the lever, which basically gives full throttle range while remaining in neutral. Familiar with the cold engine, lean, start, stall, thing as well. That said, if I set the throttle for high idle and crank this engine over on a cold start without using the primer, it will never hit a lick. If the engine has been run that day, it will start without the primer, with the throttle set for high idle.


A little more info...
Starting issue started 3 seasons ago. I've been messing with it since.
Engine is on a 24' pontoon boat that is kept dockside during the season.
Spark plugs are new, have been replaced annually, with no change noticed when fresh (QL78YC set at .030").

Thanks! -Al

 

[racerone]

Is the fuel tank above the motor??----The electric primer hoses are very small bore and likely difficult to cause the flooding .

 

[ahicks]

Yes, as is typical on most older pontoons, the tank is above the engine, but not a lot. I see where you're headed with that idea. If one of the needle and seats weren't sealing well, it would be possible they could allow the carb to siphon fuel from the tank? Though that might be tough to prove one way or another, there are fresh "kits" in each carb.

Struggling with how that might affect this starting procedure. Seems like if a bad needle and seat were allowing fuel into the crankcase, it might be more willing to try and start prior to priming? Dunno. Thinking out load.

Thanks! -Al

On second thought, I've never noticed fuel residue floating on the water surface near the engine either.

 

[racerone]

Where is the red lever on the primer positioned ?

 

[ahicks]

It's off. Will it even run if left turned on?

 

[flyingscott]

It's off. Will it even run if left turned on?

The primer has a manual operation if the red lever is pointing down it will flood the motor. Make sure the red lever is inline with the primer body.

 

[ahicks]

Mentioned above (but maybe buried), is the fact the engine is 100% after starting/when running. Perfect on idle, and making great power at higher throttle settings without any hesitation or a miss. I'm seriously doubting this could be possible with that valve in the "on/open" position which would allow fuel to pour into the carbs. That's my understanding though. Just to confirm my understanding, am I correct that this lever's function is the same as engaging the choke from the control station? 2 positions available. 1 allows fuel to flow into the carbs (on), and the second position (off) which does not allow fuel to pass through the valve. Yes?

Thanks guys. Please keep the ideas/thoughts coming! -Al

 

[flyingscott]

Check you float and needles the motor may be flooded before you even start it. Or try disconnecting the fuel line when you are done.

 

[ahicks]

Though both carbs have had kits installed recently, (which included weighing the floats and confirming float height), pulling the gas line when the engine isn't going to be in use for a few days really is a great idea. Not that I would be interested in doing that long term, but for troubleshooting purposes. At this point, to see if doing that makes a difference, more than willing.

Thanks for the idea! -Al

 

[boobie]

If it's running as great as you say, forget the testing I suggested. I always do those tests so I get an idea of what the condition of the motor is.

 

[jakedaawg]

Have you checked base timing?

 

[ahicks]

Original problem seems resolved. The engine lost spark completely not long after I posted, and troubleshooting led to the power pack, which I replaced ($$ ouch!). This got the spark back and the engine running, but a new problem cropped up. It's like a rev limiter is kicking in at about 4100 rpm. causing the ignition to "stutter" and not allowing rpm beyond that point. Up to that point, the engine is smooth and making power normally. More troubleshooting (no, it's not overheating, and temp sensor is disconnected), and it appears as though the rectifier/voltage regulator module is out now - even though it is still charging. A tip in CDI Electronics manual suggested it might be the rectifier/regulator causing the rev limiting, and that potential could be confirmed by disconnecting the yellow wires coming from the stator. I did that, and of course the rev limiting issue disappears. Another expensive part (nearly the same as the power pack!), so that's yet to be replaced.

I've been using it a little "as is", just cruising around without trying to go fast. The chronic hard starting issue seems to have miraculously disappeared (!!!). My best guess now is that my previous hard starting issues were caused by the power pack, which possibly has been weak, and possibly not supplying full voltage to the coil for the last couple of seasons? Unless things were nearly perfect in the combustion chamber it simply would not start....

I'm now wondering if boobie's suggestion of checking out the spark situation (as he suggested originally) wasn't such a bad idea. Betting the spark would not have jumped the 7/16" gap - which may have led me to the power pack issue much sooner, possibly before it crapped out completely.

Many thanks to those taking a minute to offer suggestions. All were appreciated. -Al