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excessive pressure in tanks

wvcoalminer

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so heres the thing it's a decent day here in the hills of wv and i happen to have the day off at the coal mine so i thought i would take the sled out to see my long lost bros riding about 30 miles total going from bar to bar on the way home from my 4th stop the bike started running real bad as if the timing was off or i had an igntion problem i got her home finally and when i got home she was breathing fire out of every port she could when i shut the bike off i heard a sort of bubbling sound coming from the area of the tanks when i loosened the fuel caps a lot of pressure released i changed plugs and took her out she ran fine can anyone help me with this (EDIT) . 96 flstc and the temp out was about 52 degrees when i looked at the gauge the bike was running about 200 degrees i've never had this problem before and i'm afraid that when it warms up here that the problem will happen more often so i would like to fix it now but don't know where to even start to look

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It's a vented gas cap, may have gone bad or the vent hose is kinked or pluged. I think the cap let's air in to the tank and the vent let's pressure out.
 
thats sounds right to me i am removing the dash as we speak to check the hoses could that alone make it run that bad and on a side note im sorry for the infraction in my original post
 
Ok, weren't you re-jetting because of fuel mileage here not to long ago? Or was just to make it run better? If you were re-jetting because of fuel mileage, you have found your issue. The tank is pressurizing causing the fuel to be forced through the carb because it has no were else to go. Not sure how the Heritage is vented, maybe cap, maybe through a vent tube that runs down in front of the seat. If its a vent tube, at the end of the vent tube there is a check valve. it only allows air out not in. Check this whole assembly for operation. Could be full of bugs etc. Pull it apart and blow threw it and see what happens. It is a directional check valve, meaning it only works hanging the way it is mounted. You may go back to your old jetting.


Let us know what you find,

Bodeen
 
hey bodeen good to hear from you again hope all is well.No i rejetted for performance and i checked my hosing for kinks found none i did see the check valve you are talking about and i wounder if both caps are vented caps.And as a follow up to my decel popping i replaced my vaccum piston in the carb and put in a 46 slow jet a/f screw out 2 1/4 turns runs b-e-autiful,except for pressure in the tank now
 
Yep, thats were the sweet spot should be for your carb and your setup. If you do not have a tube from the tank in front of the seat then you must have a vented cap. Hopefully someone with more exact Heritage knowledge will answer. However, inspect the caps good and the sealing rim in cap and all.
Headed to Bike for the day. Good luck

Bodeen
 
have fun and be safe man it's going to snow here today i do have a tube that runs under the seat and to a check valve i blew thru the valve and all is clear my right cap has a dent in it when i went to order new caps from jp cycles they need to know if my bike is early 96 or late 96 i love my bike but is starting to get a little frustrating .well anyway ride on and enjoy the day
 
If you still love it, maybe its time for a freshen up? New carb, cams, etc... rather than a whole new bike. Mine is an 08 with about 17k on it. All my miles in one year... so I'm kind of looking forward to the 30k-50k mark when I can justify the fun stuff!
 
so heres the thing it's a decent day here in the hills of wv and i happen to have the day off at the coal mine so i thought i would take the sled out to see my long lost bros riding about 30 miles total going from bar to bar on the way home from my 4th stop the bike started running real bad... [/note]

While plugged/pinched fuel cap/vent, hose or bad valve is likely, you may want to check the NHTSA site...and H-D dealer for any known fueling problems.

Build Years/Makes/Models: 2005 HARLEY DAVIDSON SOFTAIL
2005 HARLEY DAVIDSON SPORTSTER
2005 HARLEY DAVIDSON DYNA
2005 HARLEY DAVIDSON TOURING
Units affected: 9501
Recall Number: 04V607000
Summary: CERTAIN MOTORCYCLES MAY HAVE BEEN PRODUCED WITH DEFECTIVE FUEL SHUT-OFF VALVES. THE FUNCTIONALITY OF THE 'ON' POSITION AND THE 'RESERVE' POSITION OF THE VALVE MAY HAVE BEEN REVERSED.
Consequence: IF THE BIKE WERE OPERATING WITH THE VALVE IN THE 'ON' POSITION, THE BIKE COULD RUN OUT OF FUEL, THE EXPECTED FUEL RESERVE WILL NOT BE AVAILABLE. THIS COULD LEAD TO THE DRIVER RUNNING OUT OF GAS WITHOUT WARNING, INCREASING THE RISK OF A CRASH.
Remedy: DEALERS WILL INSPECT THE FUEL VALVE AND REPLACE IT, IF NECESSARY. THE RECALL BEGAN FEBRUARY 7, 2005. OWNERS SHOULD CONTACT HARLEY-DAVIDSON AT 1-414-342-4080.
Notes: HARLEY-DAVIDSON RECALL NO. 0118.CUSTOMERS CAN ALSO CONTACT THE NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION'S AUTO SAFETY HOTLINE AT 1-888-327-4236.
 
I have a Farmall Super A tractor, 1948, with a 4 cyl engine. When it was working hard mowing the yard, after about two laps, it would (EDIT) out and run rough. When I took the cap off, it would be full of pressure. It did this over and over. Turns out it had a sticky valve that would get hot and expand and not seat completely, How it pumped pressure back into the tank I have no idea. I took the head off, had it rebuilt with seats, valves, guides, the works, and it runs perfect now. Something to consider.


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