One my engines is cutting out... 2002 sporster twin 720s

[Killertiller]

I am pretty sure im having a fuel delivery issue but figured I might as well run it by u all. So when I was out last week noticed the one motor was only revving to 6750 or so, Other was strong at 7000. SO this time out the motor would hit close to 7 grand for split second then die down to 4000 rmps. Runs fine at anything less then wot. Idles great and no issues in a very long no wake zone I deal with. I figure gonna take carb off and first look at the fuel filter. Nover worked on boat yet so any info is helpful. Like is there external fuel filter I can look at or any other lil things I should know.

 

[Dr Honda]

I would replace the external filters, and then go thought the carbs. There is also an internal filter that could be plugged.

 

[Killertiller]

I am not near boat so can you tell me is there 2 external filters? One for each motor? Boat has single carb on each motor so was gonna just check the internal filter on carbs and hope for the best before taking carb apart. On a good note the carbs you rebuilt for my hx made ski a beast again. After messing around with everything last year and getting no riding time i had u rebuild carbs and the new owner is loving ski.

 

[Dr Honda]

Yes... there is an external filter on each engien.

BUT... I just looked at the parts diagram, and you don't have the disposable type. You have the water separator type. SO... unthread the bowl, and make sure the screen is clear, and make 100% sure the O-ring on the bowl is good. If it's hard, and compressed... replace it. If you leak air there... the engine(s) won't run properly. (it will suck air)

 

[OneT]

sorry wrong thread making new one in the right place

 

[Dr Honda]

I'm having the same type of issue on my 96 GSX 787!!! I rebuilt the carbs with OEM kits and cleaned the inline filters already! I did however replace the black springs with i think is the dull silver ones that was in the rebuild kits! Any ideas ???

start your own thread if you would like some help. AND... put it in the right section. (this is the boat section)

 

[Killertiller]

Hmmm wonder where my first reply went...lol. my android does odd things. Anyways Dr..... first thing I looked at was external filter and it was loose, Not even lil snug. If there any chance this could be my problem I'm not gonna get into carb.

 

[Dr Honda]

There is a very good chance that, it was the problem. If air can get past the seal... the pump will draw air, and not fuel. Personally... I would go buy a couple new O-rings to make sure they seal.

 

[Killertiller]

Def was gonna do that cause I notice there is a very small sweet spot when tightening both of them. Soon as there snug it pops and goes loose. Like the o ring is compressed a little. I assumed they be seadoo item???? If not I'll go get some today before I hit the lake.?

 

[Dr Honda]

Actually....


If they are popping loose... then the housing could be cracked.

Go buy 2 disposable, in-line filters, and ditch the threaded bowls.

 

[Killertiller]

Housing fine but the o riinds are flat to surface. Definitely like to put a nice inline filter so that's gonna be what I do. Thanks for into I'll get back n give u my results.

 

[Killertiller]

Housing fine but the o rings are flat to surface. Definitely like to put a nice inline filter so that's gonna be what I do. Thanks for info I'll get back n give u my results.

 

[Killertiller]

Well after tightning the fuel filter still same issue. But its really good at anything less then wot. Let's say its definetly solid under 6 grand. And if I choke it just a little it holds the 7000 rpms fine. It also lil slugish starting.. not horrible but takes few more revolutions then normal. Then fires and idles perfect

 

[Killertiller]

Just took a look at filter its loose again n won't take tighten at all. So tmrw im Gonna get a inline filter and install it before going out on lake. I'm still hopefull this is my problem . So I think I'm gonna just get a 1/4 inline fuel filter?. Lines look to be same size in and out on OEM filter.

 

[Sportster-2001-951C-Stock]

FRAM G2 filter should do the trick. I'm not 100% sure if your fuel line is 1/4 but I believe it is. Measure the barbed connectors, either 1/4 ID or maybe 5/16 ID. Must be air tight, air in fuel is no-go.

 

[Fallsguy]

I had this exact problem. Presently getting carbs rebuilt. Hope it's just ur filters though!!

 

[Killertiller]

Problem solved with a nice Mr gasket clear fuel filter for 11 bucks. Came with three sizes of nipples and has replaceable filter. Now I'm noticing a problem I was having right before this. I sucked a rope into my grate and now that engine is only turning 6800 rpms. Haven't even looked at it yet.. rope got sucked in about two foot at idle,Came ourt easily. But boats very drivable so I'm happy

 

[Sportster-2001-951C-Stock]

Great! I sucked a rope into my pump last year as well, ate it good. Was a stupid mistake and I knew it was gonna happen but you know how that goes.

Still didn't notice a difference, but I wasn't making full power then and still taking care of the odds and ends to get there.

 

[Killertiller]

Ya I knew it was happening n panicked..lmao. all I had to do was shut motors down. I don't see how it could have made motor turn 200 rpm less but the first time I went out after rope was tangled it was turning 6800 rpm. I don't see how it could damaged prop. I got it out from underneath so don't seem like it made it to prop. Maybe damaged something where the staft goes thru hull , like a rubber seal or something. I'm clueless what's there i haven't looked yet.

 

[Sportster-2001-951C-Stock]

Well, my rope was wrapped around pretty good and up in there between the impeller blades and wear ring, probably didn't help the pump any. There are a couple of small nicks in the impeller as well, and the gel-coat was gone on the leading edge. Took care of the gel-coat with some epoxy paint but RPM's didn't change as a result of sucking up rope (still 6,000 RPM and 40MPH on dream-o-meter, my dynamic timing advance isn't working yet but soon will be). I had to cut that rope out of there using a pair of side-cutters, can't recall if I tossed the rope or repaired it but I'm sure near 10 ft were probably hacked up. My driver didn't know why the motor stopped idling and was going for the start button but stopped when she heard me cussing, LOL.

But yeah, I can see how you might lose a couple hundred RPM if something goes through the pump but my pump isn't coming off till I'm ready to blueprint it, maybe this winter.

Have you confirmed your throttle plates fully open? If cable needs adjusting then don't forget to readjust the oil pump lever after.

 

[Killertiller]

Went out yesterday on boat n both engines running full power..... Not sure what was up but think im fine

 

[Sportster-2001-951C-Stock]

Check your oil pump lever adjustment, just to be sure it's correct. Remember to perform the preventative maintenance items, such as lubing the PTO spline with a shot of grease and changing the pump bearing oil, doing these things will extend the trouble-free period.