Yamaha 250 HPDI reviews

[FINRAZOR]

Is anyone running these offshore? I want to buy a used pair of them and looking for fuel/oil/maintenance survey from those having them or knowing someone who does.

THANKS!

[V.B. wells & irrigation]

They had lots of problems when they first came out. The small blocks (150-200) have always been great. Try thehulltruth.com.

[Capt Kid]

good engines overall but the ethenol played hell on the high pressure system and the high pressure pumps fail because most people dont know that they have a self contained lube system that used lower unit oil and needs to be changed just like the lower unit

[Lone Ranger]

good engines overall but the ethenol played hell on the high pressure system and the high pressure pumps fail because most people dont know that they have a self contained lube system that used lower unit oil and needs to be changed just like the lower unit

Very interesting! As much as I have read about them,I never knew that.Do all the H.P.D.I. Engines have this? [Mike]

[Capt Kid]

the hpdi engines have a high pressure pump that is belt driven by the flywheel and yes they all have the oil in them. there is two 9/16 or 5/8 inch bolts on the side that are staggered on over the other. these are the fill and drain screws.... no the manuals will not tell you this but i learned this will training on yamaha at marine mechanics institute in orlando.. there is alot of ins and outs that your average joe mechanic doesnt know

[katman2860]

The only thing that causes those pumps to fail is the lack of maintainance done on the engines.
The HPDI has 4 filters that need to be changed more frequently due to the small particles that are in ethonal fuels once those filters clogg the restrictions either cause the diaphrams inside of it to blow or the depris stuck in the filters is sucked out into the pump clogging it up.
2 of the filters the fuel/water sep and the exposed engine filter are the ones most commonly changed,these other 2 filters that clogg cause almost all powerhead failures on hpdi's .
The filter inside of the vst and the in-line canister filter on top of the vst.
To pay a good dealer to maintain the engine correctly would run about 350-370.00 to change all of the filter's but people are always trying to save money and blame the manufacturer.

[Capt Kid]

clogged filters or not the belt driven pump (moving parts) needs lubercation if you expect it to continue to work. clogged filter will cause a runibility problem with the engine because lack of fuel not pump failure as the pump spins with or without fuel. if the belt driven pump isnt properly lubed and turning approx. the same rpm as the engine it WILL fail just like and engine with no oil

[katman2860]

You are correct about the lubrication but in the field we see most pump failures due to fuel restriction issues but out of a hundred or so HPDI's we maintain some yearly but most not till something breaks we have only seen 2 pump failures those failure's did not cause the engine to fail.
The 14 powerhead failures we have seen in 3 years were all caused from fuel restrictions due to lack of maintainance or improper set up from a low ball engine dealer who cuts corners to install the engine.

[Capt Kid]

that is understood but at the same time i was refering to the high pressure pump which is supposed to be the heart and soul of the hpdi producing 725 psi for better atomization and cleaner burn etc. unless you have a major restriction, which any maintence minded owner can easily avoid. the engine will still run 2000-2500 rpm (limp home mode) solely on the low pressure side of the fuel system. meaning just because the high pressure pump fails you are not screwed.

[Lone Ranger]

How about the Optimaxes?I know there are 2 small Filters in-line.How is that Pump Lubricated?