45hp Chrysler losing power at full throttle

[Captain Bravo]

Hey guys. I have a 45hp Chrysler 2 cylinder about 1978 vintage. It has had a fuel problem for a long time that I haven't been able to figure out. After priming, it will idle and run at low throttle settings very well. The first time to try for cruising speed, it will take off ok, but after running for about 5 to 15 seconds, it slows down like it is running out of gas. If I drop the throttle back to idle quickly enough, it will continue to run. Otherwise it will stall. I can prime it and it will start right back up. After doing this 3 or 4 times, it will eventually reach planing speed, but it will never run at full throttle.
I have rebuilt the carb, and replaced the diaphragm about 2 years ago, but neither really made much of a difference. I recently found this thread by googling.
http://forums.iboats.com/showthread.php?t=258384&page=1
It says that there are 3 check valves that should be replaced. I couldn't find any check valves in the iboats store. Do I just call NAPA and ask for check valves and gaskets for a boat motor? Should I replace the diaphragm again while I am in there?

Thanks.

 

[rickryder]

Re: 45hp Chrysler losing power at full throttle

Try these guys http://www.chryslercrew.com/

 

[wickware]

Re: 45hp Chrysler losing power at full throttle

My 1970 35 HP Chrysler?s power problems (bogging/stumbling, lack of WOT holding w/o backing down) has always been dirty points (about 2-3 times in the magneto ignition system since 1985). Do you have a magneto system and have you ever checked the point?s gap (.020, dressed or replaced the points)? I'm told that 35-55 HP mechanics are basically the same except for HP items. I d/n know the years the ignitions changed jow

 

[Captain Bravo]

Re: 45hp Chrysler losing power at full throttle

I should have mentioned, I did change the points and condensor 2 years ago when I did the carb and fuel pump diaphragm. Thanks for the tip though.

My 1970 35 HP Chrysler?s power problems (bogging/stumbling, lack of WOT holding w/o backing down) has always been dirty points (about 2-3 times in the magneto ignition system since 1985). Do you have a magneto system and have you ever checked the point?s gap (.020, dressed or replaced the points)? I'm told that 35-55 HP mechanics are basically the same except for HP items. I d/n know the years the ignitions changed jow

 

[Captain Bravo]

Re: 45hp Chrysler losing power at full throttle

Thanks for the tip rickryder. http://www.chryslercrew.com/ lead me to http://www.franzmarine.com/ and my parts are shipping out today.