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Engine won’t start when hot

Dixemon

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If you haven't ever pulled your pumps, this is a good excuse to do it for sure. You can tell a lot just by being able to turn the shaft by hand and also checking bearing grease, clearance, condition, splines, ect.... might not be the problem but need to check it nonetheless.
 

FLJetBoater

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If you haven't ever pulled your pumps, this is a good excuse to do it for sure. You can tell a lot just by being able to turn the shaft by hand and also checking bearing grease, clearance, condition, splines, ect.... might not be the problem but need to check it nonetheless.
I did once, very long time ago though. Probably a good idea nonetheless. Is it safe to run the engine at idle with no pump on it? I've only seen warning about throttling up but I would assume extended time at idle wouldn't be an issue?
 

Cambo

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Did you check all the safety switches maybe you think its heat but could be something else. Run the boat and take an infrared temperature gauge and compare different points on the motors to see if something is abnormal. Those gauges are also handy when you tow to read the bearings and brakes to see if your having issues
 

Nivekot

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Vaporlock when hot? I’ve seen some posts in the forums…
 

FLJetBoater

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Did you check all the safety switches maybe you think its heat but could be something else. Run the boat and take an infrared temperature gauge and compare different points on the motors to see if something is abnormal. Those gauges are also handy when you tow to read the bearings and brakes to see if your having issues
Its definitely not a switch. Starts fine when cold, doesn’t when hot.
 

FLJetBoater

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Vaporlock when hot? I’ve seen some posts in the forums…
I was thinking this too originally. But how to tell or fix?
 

suke

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I was thinking this too originally. But how to tell or fix?
I discovered mine is 10000000% vapor lock. If I leave the engine hatch open after running it hard for a few minutes, EVEN if it's a stupid hot day, it'll fire right up. Mine does the same thing on my 212x. Mine is pretty random, though, and on both motors. Changing the plugs will help the first outting or 2 then it'll come right back. Plugs every change look near new. So it isn't fouling a plug or anything. Running the blower, or even letting it idle a bit never changes anything for me. However, opening the engine hatch when we stop for 5-10 mins it'll fire up with no issue.
 

lazergeek

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Is this effecting both engines or just one?
 

FLJetBoater

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lazergeek

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Vaperlock is a thing of the past with fuel injection unless you have low fuel pressure but would also stall out while running.

Fuel injector relay could stop working when warmed up. Once it disengages doesn't re engage. You can test by releasing fuel line from the fuel rail on that engine and try turning over or You should be able to swap the relay with the other engine.
 

CaptRedbeard

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You said the motor stalls out - so does it start and run briefly or does it not start at all? Does it turn over? If it turns over but doesn't start, is it a normal starter noise/cadence or is it sluggish or grinding at all?

A handful of good suggestions here but IMO start with the easiest solutions (starter, rectifier, etc). It's nice having two engines so you have the option of swapping parts between the two to isolate the issue.
 

lazergeek

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I highly doubt its a pump issue as it cranks over, just not starting. I could confirm spark first by removing a plug and cranking over while its connected to the coil pack and plug grounded. If good there then check fuel relay / pump
 

FLJetBoater

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You said the motor stalls out - so does it start and run briefly or does it not start at all? Does it turn over? If it turns over but doesn't start, is it a normal starter noise/cadence or is it sluggish or grinding at all?

A handful of good suggestions here but IMO start with the easiest solutions (starter, rectifier, etc). It's nice having two engines so you have the option of swapping parts between the two to isolate the issue.
It’ll start and run fine when it’s cold. I ran it on the hose for about 30 mins then turned it off. Then it wouldn’t restart. It cranks like it wants to and rumbles for a sec then just stops.
 

Beachbummer

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I also recommend trying to open the hatch to try and see if it makes a difference.
 

FLJetBoater

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I also recommend trying to open the hatch to try and see if it makes a difference.
It Doesn’t. I had it open the whole time it was running on the hose.
 

FLJetBoater

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A handful of good suggestions here but IMO start with the easiest solutions (starter, rectifier, etc). It's nice having two engines so you have the option of swapping parts between the two to isolate the issue.
What role would the rectifier play in this? Doesn't it just convert AC from engine to DC to battery for charging?
 

Beachbummer

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In case it's a leaky fuel injector... Would you crank a few times with the throttle fully open before closing them back and trying for real?
 

FLJetBoater

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In case it's a leaky fuel injector... Would you crank a few times with the throttle fully open before closing them back and trying for real?
If I push the throttle forward the engine won't crank though?
 
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