'06 HPDI ZX225 won't restart sometimes

[NutBuster]

I have an '06 ZX225 HPDI motor. According to the sticker I believe the full model number is VZ225TLR.
My motor had 150 hours on it when I bought it 4-5 years ago. I've taken extremely good care of the entire rig. My problem is sometimes the motor refuses to start after it has been run for awhile. When I put this thing in the water all I have to do is bump the motor and it starts. It runs great too. Sometimes, but not all the time, after being stopped and fishing for awhile when I go to crank and move to a new spot the motor will NOT start. I've learned to leave it alone for anywhere to 30 minutes to an hour and go try again and when I bump the starter it starts right up. Sound good and runs as smooth as a 2 cycle can.
A couple of week ago I was out and ran about 7 miles or so and stop and fished a bank line for about 45 minutes. There was a small cut on the bank with very skinny water and I trolled up into it but had to tilt my main motor up. I fished the cut for about 20 minutes or so and went back into the deeper water. After getting there I was ready to move so I dropped the motor and bumped it. Not starting! UGH! Got up checked my fuel bulb and it wasn't as tight as it normally is so I squeezed it a couple of times but this didn't help. I fished about 25 more minutes and went back and bumped it, it started right up. I rode about a mile and another boat pulled up next to me, I was just putt putting then and all was well. The other boat's folks wanted to talk so I killed my main motor so I could hear them. We talked about 10 minutes or so and they took off. I went to start mine again and NO LUCK! This time it took me just leaving it alone again for about 45 minutes or so and then when I went to start it, it came to life after I bumped the starter. Since this happened I have replaced the plugs in it and the old plugs that only had a year on them looked very good IMO. Plugs are what Yamaha calls for, BKR6EKU. This last time out was the only time it has been this bad at not starting. It has done this since I first got the rig. Usually only about twice or three times a year.
I am extremely grateful for any help you may be able to give me.

[Ranger519VS]

I would have all the injectors serviced and tested. I'm thinking leaking injectors flooding the motor.

[Brittjoyce]

I have the same motor and it does the same thing. The only thing I can keep it from doing it is trim it up about 25% before I turn the motor off. What I think it is it's not getting air.

[NutBuster]

Hey guys,
Ranger I had a lot of work done to the motor when I bought the rig, injectors, high pressure pump, filters, etc. It pulled this stunt on me with my dad in the boat probably 3 months after having this work done. Britt, I'd thought about that too. Need to check into that further.

[Invader186S]

My 3.3 HPDI does this occasionally just as you described. Not when cold, but after it has been run, it can be hard to start. I can always get it restarted by giving it a lot of throttle in neutral. Once started , it will run rough for just a bit then idle fine. It gives all the symptoms like it is flooded with gas.

The first thing I would do it check your throttle position sensor according to specs. With the throttle blades completely closed (not at idle) adjust to 0.48 - 0.52 V. Then adjust the idle screw to 0.60 V or whatever gives you a good idle. My engine seems to be very sensitive on how the TPS is adjusted.

[Bugguy]

I have the same motor and it does the same thing. The only thing I can keep it from doing it is trim it up about 25% before I turn the motor off. What I think it is it's not getting air.

^^^^^This. I have the same motor and it did the same thing to me occasionally. Trim it up past level when you start to fish and it'll start every time.

[21XDC]

Does the VZ model have a fuel pump relay like the VX models? That is what it sounds like to me. Bad relay.

[SKfishing]

If you can advance the throttle and get it to start, it is most likely the LP fuel pumps leaking into the crankcase. You may see an oil sheen on the water also. The fuel dilutes the oil in the crankcase and will likely result in a blown engine.

[CJ1]

^^^^^This. I have the same motor and it did the same thing to me occasionally. Trim it up past level when you start to fish and it'll start every time.

+3. Or a bit of throttle just above idle. If everything else checks out and it still does it the only thing I can think of is the get sensitive to back pressure when trying to start with some hours on them. Have not had the time or a victim to figure it out. CJ

[Invader186S]

When I had starting problems, it had symptoms like it was flooded since giving it throttle would help starting and it ran rough and smoked for just a bit once restarted.

It may be the LP pumps in some cases but I have removed mine and went with an electric lift pump and have still experienced starting problems.

I've played quite a bit with the TPS trying to get rid of a slight bog on holeshot. I've found advancing the TPS ( making it richer) by about 0.1V helped the off idle hesitation. But advancing it more to 0.2V caused the hesitation to return as well as causing occasional warm starting problems just as described in this thread. This is why I suggested checking the TPS setting first and making sure it is set to specs to start with.

These are small changes to the TPS setting. My starting problems seemed to be from too much fuel. I think I have my TPS dialed in pretty good. No starting problems and no off idle bog.

[bayouXpress]

I have the same motor and it does the same thing. The only thing I can keep it from doing it is trim it up about 25% before I turn the motor off. What I think it is it's not getting air.

same here

[NutBuster]

Guys I think I found the issue with this motor not starting. I replaced the fuel primer bulb and the problems so far have disappeared! I've been out three time now with none of the not starting issues! Brittjoyce, you may want to try this as it fixed my problem!

[pnut]

I had the same problem and I replaced the fuel pump relay, no problem since.