DUI Distributor problems

My DUI distributor has an intermittent problem that started towards the end of the summer.
After warmed up, i have random loss of power at speed. boat will slow to an idle and cut out. It will eventually start again (takes anything from a few seconds to 10 minutes before it will start) sometimes it will run the rest of the day with no issue, sometimes it will only let me idle back to the dock- if i try and accelerate it cuts out.

The distributor is now around 5 years old, with just over 200 hours on it. Its probably due a cap and rotor, but i don't believe they would be causing these symptoms? I believe it is acting like the coil failing.

I'm in the UK, and any Auto parts sellers I've been to don't know what service items i need as they would need a vehicle to cross reference them to. can anyone give me part numbers for the coil, cap, rotor and module that i would be able to cross reference to? I was of the understanding that any HEI service parts would work, and that i would not need to import OEM parts from DUI?

for instance would this link be suitable? http://www.ebay.co.uk/itm/362631076769

Also are there any tests i can perform on the coil and module to diagnose what is causing the problem? it has been so intermittent i have not been able to test for spark when it is not working.

The engine (Ford 351/ 93 Ski Nautique) is converted to run on LPG. i do not believe it is carb/ fuel tank/ pick up/ pump related. I have a dual LPG tank set up and the problem shows itself when running on either tank.

Peter,
What makes you feel it's an ignition problem? Maybe fuel related??? have you checked the timing?

Peter Gullen wrote: My DUI distributor has an intermittent problem that started towards the end of the summer. After warmed up, i have random loss of power at speed. boat will slow to an idle and cut out. It will eventually start again (takes anything from a few seconds to 10 minutes before it will start) sometimes it will run the rest of the day with no issue, sometimes it will only let me idle back to the dock- if i try and accelerate it cuts out. The distributor is now around 5 years old, with just over 200 hours on it. Its probably due a cap and rotor, but i don't believe they would be causing these symptoms? I believe it is acting like the coil failing. I'm in the UK, and any Auto parts sellers I've been to don't know what service items i need as they would need a vehicle to cross reference them to. can anyone give me part numbers for the coil, cap, rotor and module that i would be able to cross reference to? I was of the understanding that any HEI service parts would work, and that i would not need to import OEM parts from DUI? for instance would this link be suitable? http://www.ebay.co.uk/itm/362631076769 Also are there any tests i can perform on the coil and module to diagnose what is causing the problem? it has been so intermittent i have not been able to test for spark when it is not working. The engine (Ford 351/ 93 Ski Nautique) is converted to run on LPG. i do not believe it is carb/ fuel tank/ pick up/ pump related. I have a dual LPG tank set up and the problem shows itself when running on either tank.

The parts in your Ebay link will interchange with your DUI stuff.

I feel obligated however to warn you that you need a RED cap to keep Jonny completely happy

If you want to have a reference for local parts, use an 86 Chevy K20 pickup with a 350 engine and that will get parts that will fit also. That's one of a bunch of vehicles that could be cross referenced.

Thanks for the responses-
Pete, i dont think its fuel, if anything it feels flooded when i try to restart- holding the throttle wide open makes it start sooner after it has cut out.
also we just don't see problems with the LPG systems (there are over 50 boats in the club i belong to running LPG)- there is no pump or even filters that i'm aware of. the LP gas is pressurised, and as i said the problem shows itself on either tank.
I have not checked the timing since i set it when i installed the DUI 5 years ago (to replace my failed protec). I have not had the timing light with me when the problem has shown itself, and i have not bothered to check when the problem is not there as it runs so well (correct perfect pass times at 34mph)
I will carry the light in the boat and be ready next time. i assume if the module is failing i will see an inconsistent timing indicator, but if its the coil, would it just look weak? would i notice at all as it still runs at idle if it hasnt cut out at speed.

Jonny, i will reach out to Performance and see if they can suggest anything, thanks. i had expected they would just want to sell me their replacement parts which are not cheap, especially once international postage and import duty are added.

Keno, thanks for confirming my suspicion that the parts on the ebay link will be compatible- its the only sensibly priced ones I've found. I've ordered a set (With red cap of course!) which will hopefully solve it. if it doesn't it wont hurt to have those parts on hand for spares/ trouble shooting.

Ill also approach the LPG conversion kit manufacturer (Impco) to see if there are any service parts for the mixer/vaporiser

Ill try the trouble shooting on the performance website but i imagine it will test fine unless the problem is showing, which it is never around for long enough!

Realised I never updated this thread, and as I'm back asking for more help thought i ought to!
It turned out to be related to the LPG system after all, nothing to do with the DUI ignition.
The lpg system requires a flow of hot water, plumbed the same as a heater, to keep the vaporiser from freezing.
If this flow of water stops, it's pretty obvious as the vaporiser gets covered in frost, and the engine cuts out.
However, if the flow of water is restricted, say by some crud obstructing the block drain that the water flow hose is connected to, then the vaporiser can partially freeze, giving the symptoms I was experiencing.
As my boat is mainly used as a slalom tractor, the short busrt down the lake wasnt enough to completely freeze it, and it would thaw while idling at the end.
Next pass would sometimes be ok.
It only became clear when I drove around the lake at WOT for 5 mins,
And completely froze it, which made me check the block drain.
2 min fix had had me scratching my head for weeks.