HPDI Mechanical (high pressure) Pump

[pmat]

I am working on an engine that has not run in 3 years, it's a z150txrz. I've made progress but still have a way to go. I wanted to share something I discovered taking the high pressure pump apart. I had a good flow of fuel out of the VST and inline filter above but just a trickle to the fuel rails.

There appears to be an internal screen on the intake side of the mechanical pump. It's only accessable when you remove the pump cover. Mine appears to be gummed up and not passing any fuel. Anyone run into this? See atached photo, the screen is in the left side port which is the intake side.

I can't find the screen in any parts list so the options appear to be :

1. Remove it and leave it out
2. Attempt to remove clean and replace

I've read a number of posts where the mechanical pump has been repaced costing over $1,000. Might be worth a look....

[pmat]

Here is a close up picture.

[pmat]

A picture of the screen. I was able to extract and clean it. It is similar to the screens in the injectors just a little larger. I am told that Yamaha does not make any of the internal parts for the high presure pump available.

[pancake]

thanks for those picts! something i may need to look at.

[mrv8outboard]

Did removing that filter fix your problem? Let me know. Thank You.

[mrv8outboard]

Well I took the one here in the shop apart. Removed the filter and test ran it. *** boy what a difference. I did not see debris in the filter, but I thick it could of been ballooning out and restricting the passage. Too bad we can not purchase replacement filters.

[CaymanChuck]

Hey man I have found the same deal, how did u get that little thing out? I tried grabbing the small wire on the inside but didnt want to cause any damage....whats the trick?

[mrv8outboard]

I just wound a coarse sheet rock screw in it. You are not going to re use it any way.

[mrv8outboard]

I think I have found a source for the filter for these pumps. I am just having a problem verifying that they are the right ones. So if some one can see if their local NAPA has it to check the size would be helpful. My NAPA does not stock them and I would have to buy 50 of them, If they are correct I would get them. But I can not get any sizing from NAPA. Here is the number, you can see it in the buyers guild. 2-15001 Basket. If some one can help to get the dimensions we may have found a source.

[Slowfly1]

Did you ever get the filter? I have a HPDI motor as well not haveing any problems but would like to know if you found a sorce. My NAPA dosn't show this part in stock but they might order one.

[89 Grady White Project]

High pressure pump screens?

Great catch on finding those screens in the high pressure pump. I'm getting some really high pressure readings (1500+ PSI), but clogged screens would have the opposite effect. Glad to know about the screens if I do start getting low pressure problems.

[rodbolt17]

I am a master tech for yamaha, have been since 2005 when they offered the first master tech exam cycle.
I am also an FC 2nd class retired.
I also set up and programmed CNC lathes and mills in a former life.
no yamaha does not offer much in the way of HP parts.
Flagship marine reconditions them.
playing with a fuel leak at 625 PSI is nuts, at 1100 psi plus, its insanity.
at 1100 PSI its a bomb if it leaks.

[rodbolt17]

like I say.
fuel leaks at 625 PSI or 1100 PSI are bombs.
its also why Yamaha doesnt offer the parts.
they are trying to keep customers.
its a liability issue.
mess up reinstalling the injectors and you may find out.
crack a fuel tube? same results.
that and yamaha doesnt make the injectors nor the HP pump.
20 a pop ro clean,test and replace injector filters is reasonable, especially if the give a printout on flow before and after cleaning at two timed pulse widths.

[rodbolt17]

dont know why they dont offer parts for the high pressure pump.
unless its because its made by mitsubishi and not yamama.
mitsubishi may not offer them.

[tdillon@voselectric.com]

They do offer parts for the High presure pump, for some reason they do not offer these Micro Basket Filters. I have a 2003 HPDI with original power head beleive it or not. use a 10 micron Micro Basket filter in lieu of the original factory 3 Micron. Install a 3 Micron external 90 GPH racor filter / water seperator. This way nothing larger than 3 microns ever enters the engine. Once the external filter is cloged it bogs the whole motor down, and alot easyer to relize than cruising 4000 RPM and one of these screens gets partialy cloged and leans out a injector and blows the power head.