Just bougt a champion with a 150 vmax hpdi.. Runs awesome. Went to load her on the trailer and noticed if you give it just a little gas it sounds like a motor not getting enough gas??? But if I get into her it doesn't do that!?!? Any ideas or anyone had this problem before? Guy told me I could return it if I didn't like the boat

I have the same motor 2001 model and I'd find it hard to believe it's not fuel system related
Here are things to look into, in no particular order since it takes some diagnosis.

->low pressure fuel pumps (there are 2 and they can be rebuilt or replaced for about 38 bucks each and it the engine has a few years on it it's not a bad idea to replace and should be considered a maintenance item really)

Fuel filters (there are many on HPDI's) might be the regular one you see on the side in the clear cylinder or the medium pressure one (medal can looking one that looks like it came of a mid 70's chevy) or the filter inside the VST (but the VST being clogged usually shows up and limited rpm's, engine dies out 3000 rpms) or a the main filter\water separator coming into the engine if it has one and if not add one)

A great resource for Yamaha engines is a guy that goes by Rodbolt on iboats.com forum

iboats fourm here is a google site search for "rodbolt" on the site results (site:iboats.com Rodbolt) if the link doesn't work try the search in the google search


Travis

Forgot here are another couple of sites to look at\buy from
http://www.simyamaha.com/ You can see and buy usual maintenance items for your engine here (I use he's waterpump kits and fluids

Best overall prices here http://www.boats.net/

How have you done with that motor? Do you like it? And thanks for the advice

and what is a vst filter??

It's been great for 14 years so far, most folks consider the 2.6 liter HPDI is be "good and reliable" not so much withe the 3.3 blocks of course it needs proper maintenance. The VST on the engines is the vapor separator tank and there is a metal filter screen inside VST Cleaning

From what I've read I'm thinking lpfp also. And do you use ring free and yamaha lube? I've never owned an older 2 stroke. The last rig I had came with a 115 four stroke.

hpdi engines are great mechanically, but the fuel transmission system is so critical it causes too many problems. mine is a 02-200 and i've gone thru just about every fuel related problem you can imagine. 13 yrs of never being able to trust my engine. sometimes i wish the thing would go ahead and blow up, so i could go ahead and buy a 4 stroke with a 4 or 5 yr warranty. i never know if i'm going to need a tow or not. JMO, but stay away from hpdi's.

I always use both, yamalube is not the bad price wise but ringfree hurts

The fuel system is an area that can cause issue if not maintained (lots of filters etc). What issues with it have you had?
I've had 2 issues on the water in 14 years and one was the VST filter that was clogged and it would die out at higher rpms and the low pressure fuel pumps causing hard starting. Both are things I didn't take care of or know I should check and maintain. Overall (what I've read, heard and experienced) it considered a good reliable build

That hesitation actually sounds like throttle linkage adjustment. The timing arm needs to start moving before the butterfly`s of the throttle body. Air gap on roller to cam of throttle linkage. #37 http://www.boats.net/parts/search/Yamaha/Outboard/2003/Z150TXRB/CONTROL/parts.html

It has a hot foot on it and that's what someone else told me. It needed to be adjusted. But I was thinking how in the world can that be? Boat hasn't been serviced in a few years apparently. So it needs filters and those pumps for sure regardless.

This is an 03 hpdi 150.

How do you adjust that?? Or get it right and know you have it right?

#34,35,36 is an adjustment rod. Adjust the roller to cam until you have about a dime thickness air gap then check for full throttle from the control. Cable will need adjusted if you do not get full throttle.