Yammy 225 Excel still hesitating

[Bandaid]

Took the good advice listed here and removed in-line filter and replaced fuel filters. First time out...Horray, it worked. No problems with hesitation above 3500 RPMS. Trolled for about 1.5 hours and then, on the way home there it was again hesitating and surging anywhere above 3500 RPM's Ughh!!! What's next. <br />Chatlie

 

[dorkhead]

Re: Yammy 225 Excel still hesitating

My riends 150 Johnson 2002 does the same thing you describe and we haven't figured it out yet and neither have the local so called (mechanics). I will watch your posts for any good ideas. Boatwad

 

[Bandaid]

Re: Yammy 225 Excel still hesitating

PS:Also replaced the two fuel pumps which I thought was going to do the trick.

 

[rodbolt]

Re: Yammy 225 Excel still hesitating

have you tested the fuel system vacum and the TPS voltage while its at the surging RPM?

 

[Bandaid]

Re: Yammy 225 Excel still hesitating

No I have not. How do I go about testing it?

 

[rodbolt]

Re: Yammy 225 Excel still hesitating

your going to need a multi meter,digital. the TPS test harness and a fuel pressure/vacum guage, avalible at most auto parts stores and wally worlds. then your gonna have to go to the local yamaha dealer and look at the marine technical guide and follow the instructions.<br /> the TPS check will see if the wiper is bouncing and start with the fuel vacum guage teed into the system at the fuel pump intake, vacum should be less than 6"Hg at 5500 myself if its over 4"Hg I go hunting for the restriction.<br /> both tests will have to be performed in the water under a load.

 

[Ray Neudecker]

Re: Yammy 225 Excel still hesitating

Rodbolt is correct as usual in the tests specified. You can use an ohm meter and operate the TPI manually to see if the wiper is smooth with out fallouts. I personally would suspect a needle intermitently sticking and rebuild the carbs, since this has been one of problems I have run into over and over with these symptoms. Often after getting the delivery system straightened out and draining the fuel off, this will crop up.

 

[Bandaid]

Re: Yammy 225 Excel still hesitating

Rodbolt...I'm in Va Beach. Any way of contacting you as to try to get my hands around this problem. Or if you are in the area maybe having you take a look.<br />Charlie

 

[rodbolt]

Re: Yammy 225 Excel still hesitating

I dont get up that way anymore, used to quite a bit, worked for a few places in the virginia beach and norfolk area. <br /> if its on a trailer we can try to use B&T marine, I work for Bill occasionally. its in moyock NC. he is a good tech as well. and he has the parts and service. I have the test wheel and its close to the water so it can be water tested.

 

[Bandaid]

Re: Yammy 225 Excel still hesitating

Rodbolt. I'm going to take your good advice and give it a try. Hopefully I can figure it out. I have been really disappointed with the quality/honesty/integrity of some who have worked on the boat in the past. I hope to be able to figure it out after reading up some on engine. <br />Thanks again,<br />Charlie