Other Hesitation?

Heelz23 · Jul 15, 2017

I have a 701 Raider thats been running great, however today it started hesitating from 1/2 to full throttle and would not get up to speed. If I sat and let it idle, it would run fine for about 50 yards then start to hesitate/bog again from 1/2 throttle up. Ran fine from idle to 1/2 throttle.

Any ideas? Thanks

Pro-pulsion · Jul 16, 2017

I just responded to this very same issue on another thread lol...check the ignition coil. One test probe per spark plug boot at the same time...touching the internal metal parts that lock onto the plug tip mind you...check for the resistance values. 3.5 - 4.7 k ohms. Anything outside of that range and the secondary winding is failing which means you need a new coil. This is the single biggest electrical problem I have ever experienced on the Yamaha 701. Aside from that if it tests out fine then you will need to look a little further. This test is by far the easiest one to do as it requires no disassembly at all. Just pop off the plug caps and test.

Heelz23 · Jul 16, 2017

Thank You. Will start there. I was thinking the gas filter but when I looked at it, it looked fine, could not see water or trash in it.

Heelz23 · Jul 17, 2017

Tested the plugs and got 4.16 so I am guessing the coil is good.

I then pulled the tank valve and its good, nothing in the water separator, then pulled the lines in the tank, they looked good so I went to take the gas filter off to get a better look and when I took it off the rubber hanger I felt gas in my hand, as I pulled it off it completely came apart. Could this be my problem, or are they supposed to come apart like that? see pic below.

Pro-pulsion · Jul 17, 2017

The pic didn't show up, but I do not believe they are supposed to come apart. This could easily be an issue because the fuel lines do not pressurize, they flow according to the vacuum of the fuel pump. With a filter not holding a seal it will allow air into the fuel line accumulating air bubbles and creating lean running conditions. As for the coil, yes that coil should be fine with those readings. You can substitute the fuel filter for something a little more readily available. I like the filters Home Depot sells in their small engines department, I use one inline with my OE filter.

https://www.homedepot.ca/en/home/p.fuel-filter-for-briggs--stratton-engines.1000727930.html

Heelz23 · Jul 17, 2017

Is it showing up now? Cool, so you use that filter in addition to the oem filter? I am not sure where I got that one from a few years ago but I see this one on amazon, it a little cheaper than the Yamaha one.

https://www.amazon.com/s/ref=nb_sb_...40&sprefix=wsm+fue,aps,161&crid=1D29ATYLO08OY

BradyK · Jul 17, 2017

Heelz23 said:
Is it showing up now? Cool, so you use that filter in addition to the oem filter? I am not sure where I got that one from a few years ago but I see this one on amazon, it a little cheaper than the Yamaha one.

https://www.amazon.com/s/ref=nb_sb_...40&sprefix=wsm+fue,aps,161&crid=1D29ATYLO08OY

Negative on the picture

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Heelz23 · Jul 17, 2017

Pro-pulsion · Jul 17, 2017

No pic again lol...that filter should be alright and yes sir I do use a secondary filter after the OE filter just a little before the carbs. The reason is that the OE filters will allow some rather noticeable debris and water to pass through, this is quite evident when you see a filled filter inside the carb. This little additional filter I use having the pleated cone inside will trap water much more efficiently as well as the other debris the OE one lets through. I have not had a single issue with fuel flow and have seen much improvement with the in-carb filters.

Heelz23 · Jul 18, 2017

Thanks man, I dont understand the pics, I can see them on the posts, crazy that others cannot. Anyway, mine came apart right where the seam is at black part is on this one. I smelled a stronger gas smell the other day as well so I am guessing it was leaking gas and not holding pressure. I plan to get the filter you linked to and run it as a secondary also. I've had this ski a couple of years and have no idea if/when the carb filter has ever been cleaned. Is there some directions on how to do that somewhere?

one more try

Pro-pulsion · Jul 18, 2017

Now ya got it!

To get to the filter inside the carb you will need to remove it and disassemble. If you have no idea as to when it last saw a repair kit then you should be prepared to put one in anyway along with a new intake gasket. For that I would say JetManiac is going to be your best friend as he has all the parts you will need along with the knowledge. Plus he is just one heck of a nice guy...fast shipping too

My suggestion right now is start with the carb kit and new intake gasket between the carb and manifold. Don't re-use old gaskets, not even with sealant. It's just not worth the risk over a few dollars.

Heelz23 · Jul 18, 2017

Thanks man, I'll do that. Glad the pic finally posted, have you ever seen a filter do that before?

Pro-pulsion · Jul 18, 2017

Not I. If they are anything at all like chainsaw fuel tanks then they will be sonic welded together. On occasion even the saw tanks will leak or split at the bond line, only difference is the chainsaw tanks typically come with a lifetime warranty...at least they do on Stihl.