Seanj85
04-16-2023, 05:45 PM
First I would like to say thank you to everyone who responds to these posts. I've been a lurker here for years and have always been able to fumble my way through most problems, but this time I am at a loss. Also I apologize for the long post.
I inherited a 2003 200 hpdi Yamaha motor from my old man about 4 years back when he repowered. The reason being it was down on power and he was getting a little tired of calling a tech to service it. So it has sat for some time. I sold my big boat and wound up picking up a little mid 80s 21 steiger craft hull for a song, figured this motor would be the perfect candidate. Boat is supposed to weigh 1500 lbs, however someone before me put a transom, stringers and a floor in it so maybe a little heavier?? Prop is a 21p tempest.
Rigged it up and took it out for a test, made 3800 rpm maxed out, felt way down on power. It would make 3800 and get on plane alright but there was a lot of throttle left, and when advancing it, nothing happened. Since I know it was down on power I did all filters on it, 2 filters on VST, cannister, mystery filters as well as injector filters, took it out for another test, picked up 300 rpm to 4100 wot at 37mph. I remember this motor running like a raped ape when I was a young man, I can definitely tell it is down.
I do not want to just throw parts at a 20 year old motor, but It would be nice to get it to run correctly. I know it has low hours as my dad really didn't use it much. I have ruled out the possibility of the neutral safety switch on the motor, and the compression is excellent. linkages appear to be adjusted properly. I have also done routine maintenance such as t-stats, water pump and plugs. I can hear that each injector is firing using the old screwdriver on the ear trick. I do not see any fuel leaks, and all hoses appear to be properly clamped. I ohmed out all coils and they appear to be within spec. I am running on remote tanks, ball is good. Squeezing the ball has no effect on rpm.
It feels like a fuel delivery problem but I am not certain, this last time out after doing the filters I decided to change the HP pump with a used unit I found on the line, but had the same results: 4100 wot. Some things I noticed this past drive though was the battery is not charging as well at the upper RPM, my Garmin was reading 13.7 or so on idle but on plane was closer to 13v which seems unusual for a stator style charging system. Additionally It sounded as though the motor was breaking up a little in the 3600 - 4100 rpm range. So I am thinking maybe stator? I do not know ohm specs for it though. I saw someone on another post said they had a blockage in an exhaust tuner, could that be a possibility?
Any help would be appreciated
Thank you
I inherited a 2003 200 hpdi Yamaha motor from my old man about 4 years back when he repowered. The reason being it was down on power and he was getting a little tired of calling a tech to service it. So it has sat for some time. I sold my big boat and wound up picking up a little mid 80s 21 steiger craft hull for a song, figured this motor would be the perfect candidate. Boat is supposed to weigh 1500 lbs, however someone before me put a transom, stringers and a floor in it so maybe a little heavier?? Prop is a 21p tempest.
Rigged it up and took it out for a test, made 3800 rpm maxed out, felt way down on power. It would make 3800 and get on plane alright but there was a lot of throttle left, and when advancing it, nothing happened. Since I know it was down on power I did all filters on it, 2 filters on VST, cannister, mystery filters as well as injector filters, took it out for another test, picked up 300 rpm to 4100 wot at 37mph. I remember this motor running like a raped ape when I was a young man, I can definitely tell it is down.
I do not want to just throw parts at a 20 year old motor, but It would be nice to get it to run correctly. I know it has low hours as my dad really didn't use it much. I have ruled out the possibility of the neutral safety switch on the motor, and the compression is excellent. linkages appear to be adjusted properly. I have also done routine maintenance such as t-stats, water pump and plugs. I can hear that each injector is firing using the old screwdriver on the ear trick. I do not see any fuel leaks, and all hoses appear to be properly clamped. I ohmed out all coils and they appear to be within spec. I am running on remote tanks, ball is good. Squeezing the ball has no effect on rpm.
It feels like a fuel delivery problem but I am not certain, this last time out after doing the filters I decided to change the HP pump with a used unit I found on the line, but had the same results: 4100 wot. Some things I noticed this past drive though was the battery is not charging as well at the upper RPM, my Garmin was reading 13.7 or so on idle but on plane was closer to 13v which seems unusual for a stator style charging system. Additionally It sounded as though the motor was breaking up a little in the 3600 - 4100 rpm range. So I am thinking maybe stator? I do not know ohm specs for it though. I saw someone on another post said they had a blockage in an exhaust tuner, could that be a possibility?
Any help would be appreciated
Thank you