Warm 2000 Merc 90 ELPTO starting issues

[dandreye]

Hello All,
During a week of intensive freshwater boating my 2000 Merc 90 ELPTO would start at a 10-15th or so attempt when warm from time to time. I would first try starting it with the fast idle lever down as always, then try lifting it somewhat up, half way up, all the way up, then pushing the ignition key in - nothing would help until all of a sudden it would start and work as if no problems existed whatsover. Even starting it cold has never taken that long. Is that normal and if not what can that be? Except for the occasions described above the engine starts so-so when cold, literally perfect when warm and runs perfect in all modes. It's just somewhat rough at idle and low RPM when warm and quite a bit rougher when cold, which seems like a design issue though.
Thanks in advance,
Dmitriy

 

[achris]

Re: Warm 2000 Merc 90 ELPTO starting issues

Drasvitsya Dmitriy,

When was the last full service done? I would be looking at replacing the fuel pump diaphragms, which should be done annually anyway.

These engines do idle rough, nature of the beast.

Chris........

 

[dandreye]

Re: Warm 2000 Merc 90 ELPTO starting issues

Zdravstvuite Chris )
In fact the engine underwent a major overhaul which in my understanding included a service anyway. The brief story here is that the boat went underwater, was recovered in a few hours, the technicians reported no hydraulic impact despite the emergency switch had not been activated, completed the drowned engine recovery procedure right away but mixed up cyl #2 and #3 ignition wires, which (perhaps combined with something else) caused the engine to behave in a weird fashion, even start spinning counterclockwise at times. Before I read in the manual that white trigger wire goes to cyl #3 starting from year 1998 and up we replaced ALL ignition parts, flywheel and even cyl #2 and #3 pistons and rings although they were found to be far away from worn (cyl #1 piston and rings weren't replaced as it was always firing). So now the engine is back alive and runs well except for the anomalies I described in my previous post. I have known this boat for the last 2 or 3 years and don't recall ever seeing such behaviour in the past. It's a good point about the fuel pump - we did take it apart but had no pump repair kit, so I'm going to order it. Anything else you (or anyone else) can think of?
Dmitriy

 

[tashasdaddy]

Re: Warm 2000 Merc 90 ELPTO starting issues

also check your fuel hoses for any air leaks.

 

[dandreye]

Re: Warm 2000 Merc 90 ELPTO starting issues

Tashasdaddy:
The fuel lines from tanks to the fuel filter are copper. From the fuel filter to the engine goes a flex pipe with bulb. The pipe is quite old but wouldn't petrol leak when the tanks are full if it wasn't good? (the flexible part is at 2/3 of the fuel tanks height) I didn't see any leaks or smelled gas in that compartment but will get that checked again just in case.