2001 challenger 2000 cuts out at wot after a minute or so

[Mick76]

Hers the scoop. New to me boat this year. Boat starts and idles fine in the water. Up to 4500 rims I've not had any issues. At wot around 6000 rims is where the issue develops. It will go good at 6000 rims wot for about a minute then just bog down. Sometimes after it does this I wait a minute and idle around then give it the gas again wot and it's fine for about a minute again then cuts out. Other times after it cuts out it won't get above 3000 rims and I have to sit and idle longer for it to come out of it. But it runs fine at 4500 rpms....
Here's what I've done so far...change the ff
Fresh fuel
Got some crud out of the tank
Changed plugs

What am I missing?

 

[Mick76]

Also I tried to do a compression test. That said I know it's supposed to be done at wot but I can't get the engine to turn over at wot because of the lock out feature... how do u get around that? That said I did do a compression test on it today and all came back 100 to 110 without the throttle being at wot. I don't think anythings wrong with compression because they are all fairly close and this is a new engine put in from the previous owner. Any advice guys on im replacing my fuel lines this week along with seeing if i can get anymore dirt from the tank. Just getting alittle frustrated is all. where to look next?

 

[Dr Honda]

With a compression test, you can use a remote switch on the starter solenoid. That's the easiest way to do it. (then you don't' need a helper)


Before I can give any really info.... what engine do you have?

 

[Mick76]

Tony, here's an update. Took the boat to a shop and they found a bunch of crud in the vts. they cleaned it out and it ran fine they said. I picked it up and put 39 and a half gallons of fuel in the boat.I know its a lot. Went to go put the boat in water and no start. Crank it over 30 to 40 times and no start. Took the boat back to the shop and it started up for them no problem the next day. My question is is there such a thing as a vapor lock on these boats because I was so low on fuel? If not what do you think the problem was?
Thanks
Mike

 

[Dr Honda]

Before I give any advice... I need to know what engine you have. (as posted before)

BUT... generally NO. Vapor lock doesn't exist with these boats. The SportJet 175 had some issues with hard cold start, but they added the electric lift pump to help the newer engines.

 

[Mick76]

Sn 394276... 240 merc efi....how hard are they to start if they've run out of fuel?

 

[Dr Honda]

OK... thanks. If you add that to your signature... it will make it easier for future questions.


Anyway... they are not hard to restart if you run out of fuel. Basically... when you crank... the lift pump should be running, and it will fill the filter, and Vapor tank in just a few seconds, assuming there are no air leaks in the fuel feed hose. When I put my engine back in my boat... it started up very quickly.

With that said... did you run your bilge fan, and open the deck lid when starting it? My engine bay will fill with fumes, and my engine won't start until I turn on my bilge fan, and pull in some fresh air.