Im calling on Capt Ken for help on my yammies!

[bodogg]

I live in port st joe fl near you and I have a pair of z250 hpdi's and I just cant figure it out. last year i put the boat in storage and when i got it out to use it i realized i had a problem,i forgot to get the fuel out of it,so i replaced the fuel pumps in the vst on both engines and the filters and plugs. The starboard engine runs fine but the port engine will only idle perfect but when i throttle up to about 3000 it will sputter and fall off to about 1500 rpms so i turn it off and restart it and it will do the same every time,it will run at 3000 rpms for about a min before it starts to fall off. I also cleaned all 3 tanks new racors new fuel hoses ect. i dont know what else to do can you or someone please help? jeff.

 

[99yam40]

Re: Im calling on Capt Ken for help on my yammies!

Monitor high and low fuel pressures to see if there is a problem with them at problem RPMs

 

[Capt Ken]

Re: Im calling on Capt Ken for help on my yammies!

The fuel system needs to be cleaned including the micro filters in the HP pump and injectors. Been getting a lot of HPDIs plugged with bad fuel lately.
Leaving in the morning on vacation but will be back at the shop Monday. I'll be checking in here while gone.

 

[bodogg]

Re: Im calling on Capt Ken for help on my yammies!

thanks guys,I did not realize there were micro filters in the hpdi unit,I thought the last filter was aft of the vst pre hpdi pump. I also checked the pressure on vst while running at 3000 rpms and it held 45psi untill it started chugging then it would fall maybe 3psi at the most i did not check the low pressure pumps while at 3000 rpms but i traded the vst from the other engine to see if a change but no change.

 

[bodogg]

Re: Im calling on Capt Ken for help on my yammies!

ok thanks Capt Ken!

 

[Capt Ken]

Re: Im calling on Capt Ken for help on my yammies!

The micro filters aren't really owner serviceable. Just something we learned to do rather than send pumps and injectors off for rebuilding. You did use odiker clamps on the HP lines didn't you?

 

[bodogg]

Re: Im calling on Capt Ken for help on my yammies!

yes i sure did,the pressure is too great for hose clamps!

 

[yamatech43]

Re: Im calling on Capt Ken for help on my yammies!

Just a thought....are both engines on same tank or port/port....stbd/stbd...? Just wanting you to cover the obvious(and cheap)first....vacuum gauge inline before first ENGINE filter will tell you if vent/coast gaurd crap,ect. is stuck/clogged. 2" of vac. at idle/ no more than 4.5" at W.O.T.....good luck, ask Ken if Volvo injector screens can be used on these, curious.

 

[bodogg]

Re: Im calling on Capt Ken for help on my yammies!

Thanks yamatech43, the engines share a 400 gal tank and separate for the two 100 gal tanks. But i will try the vacuum test sunday and i will post the findings. Thanks again.

 

[bodogg]

Re: Im calling on Capt Ken for help on my yammies!

thanks guys, problem solved. As i posted on my suzuki df 90 about cleaning my injectors,I tryed the same thing on my yammy and that solved the problem with that too,I did a sea trial this afternoon for an hour and she held a constant 3700 rpms the whole time so i beleive that has her fixed,thanks again!!!!