Mariner 25HP Bigfoot fault

[Binksy]

I have recently acquired a Mariner Bigfoot 4-stroke that has an intermittent fault. It starts fine from cold and will continue to run fine for the first hour even with regular stop / starts but once it reaches a certain temperature it won't fire again. If you wait 30 to 40 minutes it will struggle to start but does - if you leave it a couple of hours it'll start fine again. I'm sure it would continue to run all day long but the hot start problem is a real nuisance.

So far, I have renewed the fuel hose & bulb and am now trying to test the coil but it a single, sealed, variety so how do I check the secondary circuit?

[uncle al]

It sounds like fuel vapuourising.

[Turbodiesel]

Is it a carb model or EFI?

[Binksy]

Is it a carb model or EFI?

It has a single carb.

Someone suggested checking the fuel tank pick-up pipe for a kink and strangely enough, my old Quicksilver tank pick-up pipe has a crease in it although it isn't kinked enough to stop flow, it might possibly restrict things a little maybe?

[uncle al]

if yours has a water cooled fuel lift pump check that there is no restriction in the water ways, I used to use a drill bit and just twist it through with my fingers not in a drill, so as not to cause any damage.

[Maximus]

Had Similar problem with an Old Merc some years ago...New Plugs and Leads sorted it..Ht's were breaking down under load when warm apparently.
By the way 'Binksy' ..Love your Artwork!!

[Binksy]

Originally Posted by Maximus

Had Similar problem with an Old Merc some years ago...New Plugs and Leads sorted it..Ht's were breaking down under load when warm apparently.
By the way 'Binksy' ..Love your Artwork!!

That'll be my cousin, Banksy. He has way too much money for a Graffiti vandal!

Did you get mis-firing while running? Mine is as sweet as until you turn it off.
I would change the HT leads but they are one sealed unit with the coil. I have cut back an inch where the plug cap screws into the lead and reconnected but as yet haven't run the engine to test if this might have made a difference.

[Binksy]

Originally Posted by uncle al

if yours has a water cooled fuel lift pump check that there is no restriction in the water ways, I used to use a drill bit and just twist it through with my fingers not in a drill, so as not to cause any damage.

Not sure but it looks very similar to this one though...

[uncle al]

That is not the pump I was thinking of

[Maximus]

Originally Posted by Binksy

That'll be my cousin, Banksy. He has way too much money for a Graffiti vandal!

Did you get mis-firing while running? Mine is as sweet as until you turn it off.
I would change the HT leads but they are one sealed unit with the coil. I have cut back an inch where the plug cap screws into the lead and reconnected but as yet haven't run the engine to test if this might have made a difference.

Ran PERFECTLY till warm, THEN coughed and spluttered!!... Like a Old Tory in a Lap Dancing Bar!...