150 xr6 loses rpm at high speed,,,,

[john grimm]

pls help, i have an 1999, ( sold as a 2000) 150 xr6 on a 01 896 (special ordered for that yr by a guide he backed out i picked it up as a warranty exchange) it will run great for a while, then about 10-20 min.of running it will lose rpms and not go over about 2500,...would surge like that for a bit, then i would just idle back,....i put fresh gas in, changed fuel filter,some old lines, took it back out and still does same, now instead of surging it went to just the low rpms totally, same scenario ran good for a while then this crap......read several thing on internet, not enough oil getting to gas,,ect,,,anyone have ideas,,,,,thanks john

 

[Bob Bourget2]

There are a lot of possibilities, but...

-1] Compression check

-2] Fuel supply and quality

-3] Electrical {spark to each cylinder}

Start here......

 

[john grimm]

on the elecrical, what are the modules called that the spark plug wires come out of, are those the coils, what are odds those are bad, how do i check, thanks for the fast response bob!

 

[Bob Bourget2]

You would need a "Spark tester". It is merely a piece of plug wire {you could make your own} cut back, with the center electrode exposed, connected with a piece of clear hose {or plastic}, with an approx 1/4"-1/2" gap, connected between the plug and existing plug cap. Turn over and watch for spark!

 

[TOMMY RICH]

My 90 was doing that when it was new and it turned out to be a coil pack....

 

[john grimm]

what gets me i guess is how it runs good top end full throttle for 10-20 min, then starts to act up.Do they get hot then start to go out?? ,the fuel is new and i put quicksilver additive(cleaner/stabilizer) in also hoping it was just fuel/carb issues, dont think im that lucky lol.... i will check the spark and get back with yall, thanks again for the help! also where is a reasonable place to get cowel parts, the skegs are breaking on mine and the roller is broke,.....

 

[Bob Bourget2]

Typically, when electrical components "heat up", is when they will act up. If it runs good for the 15-20 minutes, you can pretty much rule out you have a compression issue, and to a lesser degree the fuel system.....all signs point to electricals.....based on your "complaint".

 

[john grimm]

well they all have spark,

but i guess id have to run it a while to get them (hot) to be accurate,? guess ill have to wait to take it back out, what do these run, maybe ill just replace them all so its done.

 

[Bruce Freeman]

So it dosn't run rough it just won't run at max rpm either in or out of gear? Did you let it cool down and see if you had the same results? Open the gas cap and listen for a sucking noise and then try it? Vent for the fuel tank might be clogged and starving it for fuel?



BF

 

[Bob Bourget2]

If in fact it is running for a solid 15-20 minutes, the fuel system becomes "less suspect". Typically, any venting or restrictions will cause performance issues as soon as the motor is put "under load". A vacuum test will quickly show if there any restrictions. There should be less than 2"Hg........

 

[john grimm]

im guessing at the time, it cranks right up, gets on plane fine the first time, then i can run to a hole m fish a little fire up and make another run and it starts the (symptoms)...

first it starting surging at high rpm, like i was running out of gas kinda...i got home, drained tank, put fresh fuel in, and treatment, sprayed some cleaner in carb, changed fuel filter,( it was full of gelled crap),, so i thought that was the culprit, next time out, same thing ran fine at first then it did the surging thing then went into a low rpm only run, like 2500-3000 maybe,,,just had no power, now its only under load it does thism i can have it out of gear and it revs right up......

 

[john grimm]

ill check the fuel vent cap and see if its working

 

[Bob Bourget2]

Ok, so now we have more and different info. If you are guessing at the time frame, and the filter was in fact full of "gelled stuff", pull the carbs and clean them. Replace fuel lines and primer bulb unless you've done this recently. Inspect fuel tank pick-up and anti-siphon valve. Replace pulse pump. We'll go from here......

It is important to be as accurate as possible with your diagnostics when asking for help.....

 

[john grimm]

sorry bob, i figured i ruled out fuel stuff by what i did and it running good for a while i thought if it was fuel it would be acting up right from the start, but im no pro thats why im asking for help lol,...i for got about the filter being that bad, as this was done couple months ago, and i just took it back out sunday,ill do all that stuff and get back with ya, where should i go to get these parts, and i think ill change the coil packs as well, any suggestions,im in tomball texas, any good hones dealers near me,? thank again for everyones input... oh and where and what is a pulse pump.

 

[Bob Bourget2]

Coils {CDM'S} are expensive, don't change them unless you have to. If you get me your serial number, I can look up all the parts for you. Members get a 10% discount!

 

[john grimm]

sweet, serial #0T065673 i took apart the black box that is before the filter,yea it was full of hard yellow particles, old gas i guess,..the screen on pick up was clean check valve clean, gonna change it out anyway, lines also like u said,...would like to know on the coils though, ,(although sounds like my fault for not storing it right, usually i fish all yr but last yr i didnt. ....i have alot of hrs on it,its getting up there in age...not sure how long coils should last. this site has been a great help,wasnt expecting the quick response ..awesome!, will recommend to my friends!

and Bob do u sell the parts?...

 

[Bob Bourget2]

We do! I will have Mark Lewis get you a quote.....thanks!

 

[john grimm]

as far as the carbs go, do i really need to take them off to clean, then i would have to re-tune them, ?? not a carb guy, lol would the cleaner break down any of those particles with them on the motor,. and could you check the correct plugs for me also, want to verify, i had them changed couple yrs ago, guy said factory had wrong ones in??? so who knows....also can u check on steering cables for me,they are tight, tried to grease them ect. still hard,think its in the line itself,... is a dual cable set up.thanks BOB.

 

[Bob Bourget2]

It sounds like there was / is a lot of debris in the system. You'd be doing yourself an injustice if you didn't do it. It doesn't take much to score a piston. If you find them clean once apart, at least it's piece of mind. I can walk you through a carb synch if you decide to go through with it.

 

[john grimm]

thanks, sounds like ill have to do it lol,..will Mark contact me on here for the pricing, do ya need my email. is there an average time on cdm's to last?

 

[Bob Bourget2]

I have your e-mail if it is the same as you listed. Mark will get to you shortly. CDM lifespan? Don't replace one {or six} unless they fail. They could last as long as the outboard.