1995 Pro Boss GT40 EFIPCM 58 HO Multiport EFI wonbt start

"I have a 1995 Hydrodyne grand

"I have a 1995 Hydrodyne grand sport inboard with a Pro Boss GT-40 EFI,PCM 5.8. HO Multiport EFI
it runs great, accept if I run it then stop for around an hour and don't open the motor cover. it won't start.(just cranks)When this happens I have spark. If I open the motor cover and wait a half hour or so it starts right up. it’s kind of like a vapor lock. I’ve seen on line other people with the same motor in different brands of boats with the same problems with no answers.
I think this was the first year for the multiport. somebody must have the answers?
Jeff"

"Jeff, I am expieriancing the

"Jeff, I am expieriancing the same problem with a 98 Nautique, I will let it sit for about 20 minutes w/ engine cover up and it will restart fine and performance is good. I put a new fuel pump relay on because it was chattering and tested the outputs leads for voltage to both the low and high pressure pumps S/B >10.5V both low and high pressure were 11.8V OK! now I disconnected each pump seperately and listened for them running and found the low pressure pump to be abnormally noisy (growls) while the high pressure was a soft humm. Try this on yours and see if your pump have the neccassary voltage supply, then do the listen test. I am going to try a pressure gauge next on the fuel rail S/B 31psi(+-3) @idle, 39psi (+-3) key on eng off for initial system start. This should isolate the pump performance. Good luck! Keep me informed I will let you know how mine goes."

Re: "Jeff, I am expieriancing the

I too have the exact same problem of a 1995 MB Sprots 210 with the PCM GT-40. When cold, starts right up and runs great. Once at temperature and it sits at the dock for a few minutes, won't restart. Open the hood and let it cool to below 140 degrees, restarts great. I've replaced both the high pressure and low pressure pumps and still the problem continues. Next will be the coil. Who has a solution here?

I had the same problem with my '98 nautique. The problem is a starter relay located on the computer box on the rear of the engine. As I remember my buddy found this out and was able to help me out. He bought a relay from auto store for~ 10 bucks and replaced all three (I believe) on the back of the computer box and it never did this again.

Had same problem on my '95 MB Sport. Had problem everytime I was out. Just had starter switch replaced and had no problem for the past week. Hope it doesn't start again. Good Luck

Does anyone have a solution? I have same problem but cannot find proble. Same symptoms on all forums but no answers. Anyone?

The "engine compartment gets too hot" has become an all too common event since the reformulated gasolines have been introduced. The consensus among the marine engine marinizers is that the engine compartment needs enough "ventilation" to keep the temperature at the top of the compartment below 150 deg F during a hot soak. Practically, (if you are lucky) this means using the blower to cool things off - typically, you'll add another blower and have it draw hot air from the top of the compartment after shutdown.