Firstly, hello everyone. I've scoured the forum for info in the past but not posted before.
We have a 1965 Forty Minus. It starts fine when cold and runs well on full throttle. It pumps a good amount of water. As the motor becomes fully warm (maybe 3-5 mins use) there is possibly a very slight reduction in rpm, but this is very subtle.
The trouble is, if the motor is shut off, it's not possible to restart it. I've tried all shorts of combinations of choke and throttle.
If allowed to cool fully, it will the restart no problem.
Any ideas? Could this be a head gasket or carburettor issue?
For reference, fuel is new, 10:1 2-stroke oil, fairly new spark plug (good spark evident when testing it cold but haven't tried it hot).
40 minus hot starting problem
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Gilesharrison
- Posts: 2
- Joined: Mon Aug 15, 2016 8:49 pm
- Location: Cumbria
Re: 40 minus hot starting problem
Need a bit more info.
Is it hard to turn over when hot?
How warm is the water comming out the tell tail? Is it warmer than your pee. If your unsure ....
Check the spark once hot.
Is it hard to turn over when hot?
How warm is the water comming out the tell tail? Is it warmer than your pee. If your unsure ....
Check the spark once hot.
"THE KING OF BLING"!
Is it better to over think, than not think at all?
Is it better to over think, than not think at all?
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Gilesharrison
- Posts: 2
- Joined: Mon Aug 15, 2016 8:49 pm
- Location: Cumbria
Re: 40 minus hot starting problem
Thank you for the reply. I'm sorry, I'm new to this forum and Seagull maintenance.
When hot, the feel of turning the engine over is similar to when cold. It certainly wouldn't turn over by spinning the flywheel by hand, as I've seen described. I haven't got a compression tester but when cold, with the spark plug removed it feels like there is lots of compression.
I try not to make a habit of weeing on my hands, but I'd say the water from the tell-tale is similar in temperature. It definitely doesn't seem to be overheating. There's no steaming, etc.
What is the best way to test the spark when hot? When cold, I removed the spark plug and held the ground electrode against the block whilst turning the engine over with the starter cord. The spark looked strong then, I suppose I could try that when hot but is there an easier way?
Only othe point: there's maybe a bit of a dribble of fuel gathering in the carb air intake. It seems to form a slight puddle there after running for a while.
When hot, the feel of turning the engine over is similar to when cold. It certainly wouldn't turn over by spinning the flywheel by hand, as I've seen described. I haven't got a compression tester but when cold, with the spark plug removed it feels like there is lots of compression.
I try not to make a habit of weeing on my hands, but I'd say the water from the tell-tale is similar in temperature. It definitely doesn't seem to be overheating. There's no steaming, etc.
What is the best way to test the spark when hot? When cold, I removed the spark plug and held the ground electrode against the block whilst turning the engine over with the starter cord. The spark looked strong then, I suppose I could try that when hot but is there an easier way?
Only othe point: there's maybe a bit of a dribble of fuel gathering in the carb air intake. It seems to form a slight puddle there after running for a while.
Re: 40 minus hot starting problem
Try giving the carb a clean. The float may be sticking a bit and flooding the engine... that would cause it to not start when hot.Only othe point: there's maybe a bit of a dribble of fuel gathering in the carb air intake. It seems to form a slight puddle there after running for a while.
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"THE KING OF BLING"!
Is it better to over think, than not think at all?
Is it better to over think, than not think at all?
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headdownarseup
- Posts: 2484
- Joined: Thu Apr 04, 2013 2:26 pm
- Location: bristol
Re: 40 minus hot starting problem
A small residue of fuel inside the carb cowling is quite normal for a lot of 40 series seagulls. (a lot of mine do this 
)
Water flow from the "tell tale" shouldn't really be any more than lukewarm, and roughly the thickness of a pencil. If it's hotter/thinner (like a dribble) than this you've potentially got problems. (possibly a bunged up water jacket which you'll need to remove the cylinder head to find out)
I'd start with the more simple things first to see if there's any improvement.
Start with cleaning the entire fuel system. The inside of the tank will often have deposits of verdigris and nasty dried up oily sludge (a greenish/blueish residue or more often black/brown) which needs fully removing.Worse still, RUST if you've got a steel tank. Oven cleaner like Mr.Muscle or caustic soda works really well for this on brass tanks, but be very careful in how you use this stuff as it's very caustic.
Fuel filters x 2. 1 inside the fuel tap and the other inside the banjo bolt where the fuel line connects to the carb. Both get blocked up from the gunge inside the tank.
Fuel line should be fairly obvious to see if there's a blockage anywhere.
The carb will need a good cleaning too. Carb cleaner works ok, or better still a complete strip right down to component form and rebuild from there. Diagrams are available if you need them for reference. Needle jets get replaced (often for the wrong reasons imo) so perhaps it might help to know which jet you're running in the carb at the moment in order to optimise your gulls fuel requirements. Seeing that your 40 minus was made in 65 it's probably still running with the conventional 10:1 jet. (keep it that way as they run much better like this imo)
Give the spark plug a go over with a wire brush and check its gap, same with the points too. (.20 thou for both plug and points or metric 0.50mm)
Give it another go in the tank and see if there's any improvement with the hot and cold starting and report back.
Jon
)Water flow from the "tell tale" shouldn't really be any more than lukewarm, and roughly the thickness of a pencil. If it's hotter/thinner (like a dribble) than this you've potentially got problems. (possibly a bunged up water jacket which you'll need to remove the cylinder head to find out)
I'd start with the more simple things first to see if there's any improvement.
Start with cleaning the entire fuel system. The inside of the tank will often have deposits of verdigris and nasty dried up oily sludge (a greenish/blueish residue or more often black/brown) which needs fully removing.Worse still, RUST if you've got a steel tank. Oven cleaner like Mr.Muscle or caustic soda works really well for this on brass tanks, but be very careful in how you use this stuff as it's very caustic.
Fuel filters x 2. 1 inside the fuel tap and the other inside the banjo bolt where the fuel line connects to the carb. Both get blocked up from the gunge inside the tank.
Fuel line should be fairly obvious to see if there's a blockage anywhere.
The carb will need a good cleaning too. Carb cleaner works ok, or better still a complete strip right down to component form and rebuild from there. Diagrams are available if you need them for reference. Needle jets get replaced (often for the wrong reasons imo) so perhaps it might help to know which jet you're running in the carb at the moment in order to optimise your gulls fuel requirements. Seeing that your 40 minus was made in 65 it's probably still running with the conventional 10:1 jet. (keep it that way as they run much better like this imo)
Give the spark plug a go over with a wire brush and check its gap, same with the points too. (.20 thou for both plug and points or metric 0.50mm)
Give it another go in the tank and see if there's any improvement with the hot and cold starting and report back.
Jon