restarting a 1994 DT75

[domason@aol.com]

I have a 1994 DT75 outboard motor on a pontoon. I change and clean the sparkplugs everytime I launch the boat. I use stabilizer in my fuel. Motor has a new impeller with about 30 hours. The motor starts extremely easy, even after having been stored for the winter, and while on the water it runs very smooth. Problem is that after it runs for some time, perhaps an hour, and I turn the motor off to fish, I have an extremely hard time restarting the motor. some times it takes 15 minutes of turning on and off the starting button, always running the risk of running down the battery. What could cause my problem?
Danie

[Solarman]

What do the plugs look like after running on one of these trips?
When was the last time the carbs were soaked and cleaned?
Does pumping bulb help when restarting, or do no good?

There are a number of possibilities that can cause this type of problem.
First I would look at fuel, and spark to plugs. I might take a timing light on one of these trips. The next time it happens, clip to each plug wire, just to see if spark is at each plug.if spark present at each plug, I'd look at fuel. I might pull plugs to see if wet with fuel, or water when this occurs? If no spark, I'd look at anything electrical that might be affected by temp from running.

I might also look at temp of each cylinder when running on muffs, to see if there might be possible blockage of cooling water to lower areas of block (where sensor is not located). If there are temp problems, it is possible that moisture may be getting into cylinders after running for a period?

Like I said, there may be many things that could cause such a problem. Such as vapor locks in fuel system?

Good luck, add more info, and maybe we can get a close pic of what might be causing your issue.

[domason@aol.com]

problems starting DT75

Thank you for the promt response. I will try all your suggestions, starting with the fuel bulb. I think I will replace it to start off.
Daniel