Yamaha HPDI 200 RPM Problem.. HELP!!!!!

Hi guys, im new to the forum but have been reading for quite a while. I have a 23' open fisherman with a 2004 200hp Yamaha HPDI with less than 100hours on it. About a year ago i had parked my boat at a dry storage and never started her up again due to my 2 newborn boys took all my time. Last month i decided to take her out and guess what....yup...NO GO !!!! After reading advice from friends that own HPDI's and this forum, i have done the following: First, i had to change the VST tank fuel pump cause it was a mess ($800)!!! Along with that came the fuel pump filter as well. I also changed the clear canister paper element filter that leads to the VST ($25). i then changed all 6 spark plugs, drained and refilled gas tank. It finally started up, so i took her for a ride. On the first attempt, for the first 20-30 min she wouldnt go more than 3300-3500 rpms. after playing with the throttle a little longer i finally got her to 4000rpms. i took her back to the dry storage and realized i had to change the water/fuel seperator filter as well!!! I changed that and took her out today. Now she starts up great, fairly smooth up to 1500rpms where i notice a slight shaking that wasnt there before. When i punch it, it would hesitate for a second and take off, but gets no further than 4400 rpms!!! I came back to my house and read there was another metal filter (strainer) after the VST tank that leads to the mechanical fuel pump !!!! I decided to go out & buy a new one ($100) and install tomorrow!!! I really hope its that metal filter cause after that i would be stumped!!! Any recommendations???

Re: Yamaha HPDI 200 RPM Problem.. HELP!!!!!

you MUST also use the correct clamp and a CV boot clamp tool toinstall that medium pressure filter.
DO NOT use a hose clamp.
be very careful releasing the HP pump side of the filter,its a quick connect.
use a pair of needle nose,hold the black plastic portion into the chrome fitting while pulling the line off.
be very careful releasing the line between the VST and the filter.
that line has to carry 50 PSI and its 69 dollars from yamaha.

Re: Yamaha HPDI 200 RPM Problem.. HELP!!!!!

Thank you Rodbolt for the great advice! Quick question, what is the difference between the hose clamp & the CV clamp that it can't be substituted?? Also, what do you consider to be the best gas solution for the gasoline that may be either dirty or have humidity in the tank?? Thanx again!!

Re: Yamaha HPDI 200 RPM Problem.. HELP!!!!!

The ultimate HPDI do it yourself guide is in a very unlikely place,
2gringos.blogspot.com
An expat in the carribean has similar problems with hpdi, jumps thru 20 hoops with almost no tools,parts or dealer support and comes out with a working engine. Search his archives around oct 09. Be prepared to spend some time, the motor stuff is mixed in with some island life stuff. MaryD

Re: Yamaha HPDI 200 RPM Problem.. HELP!!!!!

TwinAceMarty said:

Thank you Rodbolt for the great advice! Quick question, what is the difference between the hose clamp & the CV clamp that it can't be substituted?? Also, what do you consider to be the best gas solution for the gasoline that may be either dirty or have humidity in the tank?? Thanx again!!

Click to expand...

Drain tank and clean