06 BIG DOG MASTIFF SHUTTING DOWN

[sparky_06]

Hey guys I'm hoping y'all can help with an issue I've been having. Sometimes when I'm riding the mastiff will sputter and shut down completely. Like I've ran out of fuel. Pull over and most of the time she'll fire right back up. I was left stranded on a memorial ride once for 3 hours waiting for a tow truck (damn thing fired right up once the tow got to me). I've cleaned and adjusted the carburetor and replaced the air filter. My cousin suggested it could be getting vapor locked. has anyone else experienced this issue and know the fix?

 

[bdm7250]

When it happens loosen your gas cap. If your gas cap is not venting proper you'll get vapor lock.

 

[HMAN]

Make sure the ECH plug is tight. Is this a regular occurence or random events?

 

[sparky_06]

it's a regular occurrence but sometimes it's after 4 hours of riding other times it does it 5 miles down the road. when it happens at first if I goose the throttle it'll usually correct itself but only for a few minutes before it does it again and goosing the throttle doesn't work and it shuts down. I haven't rode in a bit so I need to get on it and try venting the cap to see if that works. I live on a dirt road so it wouldn't surprise me if sand has clogged the gas cap vents.

 

[HMAN]

it's a regular occurrence but sometimes it's after 4 hours of riding other times it does it 5 miles down the road. when it happens at first if I goose the throttle it'll usually correct itself but only for a few minutes before it does it again and goosing the throttle doesn't work and it shuts down. I haven't rode in a bit so I need to get on it and try venting the cap to see if that works. I live on a dirt road so it wouldn't surprise me if sand has clogged the gas cap vents.

Hmmm, it does sound like a fuel supply issue. Check inside your tank for pieces of floating liner. Some have a green color, some are red. The liner will clog the petcock screen. I found some rather big chunks in mine. Worth a look.

 

[sparky_06]

Hmmm, it does sound like a fuel supply issue. Check inside your tank for pieces of floating liner. Some have a green color, some are red. The liner will clog the petcock screen. I found some rather big chunks in mine. Worth a look.View attachment 66639

thanks for the tip! I'll check it out.

 

[Pops]

Had same problem.....BD proprietary electrical system /EHC. Had bike rewired to Harley wires....no more problems !

 

[sparky_06]

Had same problem.....BD proprietary electrical system /EHC. Had bike rewired to Harley wires....no more problems !

pops did you do this yourself or take it to a shop?

 

[Iman]

Check the easy problem first. Gas cap vent. If it has a white piece on it unscrew it and throw it away

 

[sparky_06]

Check the easy problem first. Gas cap vent. If it has a white piece on it unscrew it and throw it away

what is the white piece. im a little hesitant to just throw parts away

 

[HMAN]

what is the white piece. im a little hesitant to just throw parts away

It is a plastic piece of the vent. It has caused issues so most folks just take it off the cap. You dont have to trash it right away, but you will eventually as there is no real use for it.

Gas cap-how to tell if it is venting??

So... I know this has been covered, & I've read a bunch on it, but I think I may have a gas cap venting issue and I'd like to know how to find out...also how to fix it if it is an issue. I noticed as I was waxing the tank after a ride today that the tank seemed to pop as if it had been...

www.bigdogbiker.com

 

[Pops]

pops did you do this yourself or take it to a shop?

Namz Custom Cycles
Oreland PA
Jeff Zielinski

A number of Dog owners had their bikes done there..... top notch work !

 

[Pddain]

I posted my issue on the wrong thread, but here is a pic of the two caps. New cap on the right. Old cap on the left. Too cold to ride today but will put the old cap back on and ride for a while. I am sure the issue is the white vent is not allowing enough air and is creating a vaccum as you all said have stated thanks

 

[Mickmorris]

I posted my issue on the wrong thread, but here is a pic of the two caps. New cap on the right. Old cap on the left. Too cold to ride today but will put the old cap back on and ride for a while. I am sure the issue is the white vent is not allowing enough air and is creating a vaccum as you all said have stated thanks View attachment 82579

Yep! You’re going to find that’s the culprit!

 

[Little-Boo]

I have a 2006 Mastiff and used to have the same issue. The bike did fine at lower speeds but once I got on it the engine would shut off as if I ran out of gas. I did the gas cap as others had done, however the issue continued with me. So I change out the ignition switch and key to a Sportster Ignition and that took care of my problem. Start the bike and wiggle the key if it shuts off or stumbles you need to change out the ignition switch. Some on here have gone to a tractor parts store and bought a ford tractor switch and that worked for them. You may have to modify the hole where the switch goes on the Dog. Do a search for ignition switch there is some good information from various riders on the subject.

Carlos

 

[lentzii]

Hy, leuchten die LED an der Zünd box? Crank Sensor? gruß Lentzi

 

[Pddain]

Thanks, I have a new switch and replaced the ignition module when I put a new 585V Cam on due to a new top end, but will test it. Been a bit to cold and wet to ride. Below 32F and I throw in the towel. Used to ride in the snow in Reno, but not on a Dog. Getting soft or smart depending on your view.

 

[Pddain]

Just too slick

 

[Sven]

I'll take a guess just on a basic cap v. emissions/safety cap.

White housing: My thought is both emissions and addressing tip-over. The heat is going to expand and having a cap with a hole only like a lawnmower, those used to cause the vapor/heat to expand out of the tank and you'd also lose the knock agents along with the gas vapor. So emissions wise, this took a ball and spring times two. So think of a ball on top of a spring; this will be pulled down via vacuum and also the tip-over keeping the gas in the tank.

The other ball is on the bottom, with spring on top; this is for expansion and blows off into a tube in the tank, dumps in a charcoal canister, and now is exposed to the air via emissions loop... kind of. I left out a more technical flow from tank to intake manifold and help burn the overflow, like say at the gas fill, top it off too much/too late, and saturate the canister and how you address that... with the fuel heading down that tube in the tank.... if applies.

So if you don't care about tip-over on a hot(er) pipe near the head and torch the bike, just blow in either hole you can see. Suck it back and it should flow both ways = Not the cap.

Cap with balls and springs, the theory is either it sucks or blows both ways on the flip of holes. If they match blow for blow v. blow no blow, has to blow no blow to work, right? Where no blow is tip-over side. Blow for blow, tip is disabled.
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Sensor wise, I would look at it as a heat factor. Meaning, it reaches a point of max heat and fails, then comes back online when cooled.

Fuel loss or falling on its face [vacuum] at heavy loads and never losing spark is fuel flow.
Carb-Tree flow of jobbers:
a. Cap = vac.
b. Petcock = clogged/no gas.
c. Fuel line = kinked/internal bubble of material leaving wall and closing flow.
d. Carb = Needle stuck/float level.

FI:
a. Fuel pump = Low pressure at the pump.
b. Fuel line = Internal bubble of flex line/steel line crimp.
c. Injectors = spray holes clogged/plunger losing magnetism to retract needle and expose spray holes.

WOT I miss?

 

[Pddain]

Sven: thanks. You covered it all.