• The Roadster Factory Recovery Fund - Friends, as you may have heard, The Roadster Factory, a respected British Car Parts business in PA, suffered a total loss in a fire on Christmas Day. Read about it, discuss or ask questions >> HERE. The Triumph Register of America is sponsoring a fund raiser to help TRF get back on their feet. If you can help, vist >> their GoFundMe page.
  • Hey there Guest!
    If you enjoy BCF and find our forum a useful resource, if you appreciate not having ads pop up all over the place and you want to ensure we can stay online - Please consider supporting with an "optional" low-cost annual subscription.
    **Upgrade Now**
    (PS: Subscribers don't see this UGLY banner)
Tips
Tips

TR2/3/3A gas pouring out of the carb vents

2billydavies

Senior Member
Offline
hi everyone.... me again. shocking!
can anyone tell me why on occasion when my TR3a is idling gas just pours out of the carb vent pipe on top? it did it again today.... just pouring out of the left carb. no clue why. I undid the bolt on the top of the float bowl, took off the lid... then bolted it back on and it stopped. before I did my engine rebuild the right carb did it. same thing g.... i undid the lid, put it back on, and it stopped. the vent pipes on my carbs do not lead to anywhere.... just a long skinny pipe sticking out. I ts driving me crazy!
thanks.... again... for the great help!
 

Geo Hahn

Yoda
Country flag
Offline
Sounds like a stuck valve in there. Sometimes you can clean them and work them a bit and they are fine, sometimes it is best to replace.

There are several types of valves - some have a needle and seat and some use a small metal ball (like a check valve).

For both types you usually remove the pin that hold the arm, then undo the hex that is the body of the valve.

If an engine sits for awhile they are prone to sticking so if that is the case possibly just working them a bit will free them up.

Could also be a sunk float -- to check you can remove the float and shake it listening for gas inside.
 
OP
2billydavies

2billydavies

Senior Member
Offline
awesome. I thought maybe something was "stuck." the car sat for 6 months during the rebuild. im going to check everything you suggested. thanks again... this forum has been a total lifesaver!
 

Geo Hahn

Yoda
Country flag
Offline
Even if it is a valve - check the float anyway while you have it open. You can bend a length of stiff wire (even a big paper clip may work) into a tall 'L' and slip it down alongside the float to hook it underneath and lift it out. If there is gas inside it, it is probably best to simply replace it rather than try to repair.
 

TR3driver

Great Pumpkin - R.I.P
Offline
My opinion, if you find the valves with the metal ball, chuck them and use the Viton tipped needle valves. The valves with the balls (aka Grose Jets) are commonly sold as improvements, but I have seen them cause exactly the problem you describe more than once.

Also, take a look at the short sections of soft line that connect the carbs to the line from the fuel pump & the bridge piece between the carbs. They can deteriorate internally and shed bits into the fuel, which can block the float valve open and cause overflow. I consider it worthwhile maintenance to just replace them every 10 years or so.
 
Similar threads
Thread starter Title Forum Replies Date
Celtic 77 MGB LeMans Gas filler MG 10
mctriumph General TR NEVER start a car with stale gas Triumph 0
TomMull GT6 Gas Tank Outlet Triumph 0
B TR6 Gas on spark plugs Triumph 7
Briancole702 MGB-GT 71 Mgb gt no gas in float bowls MG 1
edkap2002 TR6 gas tank sounds Triumph 8
MGTF1250Dave T-Series TF Gas Tank MG 6
B General MG 77 MIDGET Gas tank sending unit MG 1
G Wanted gas tank dip stick for mgtf 1555 MG Classifieds 1
Celtic 77 MGB Pessimistic Gas gague MG 10
B gas leak underneath the carburetor Restoration & Tools 2
T TR2/3/3A TR3 Gas Tank Grounding Triumph 9
P MGB Mgb gas tank cap MG 7
LAW75 Concours: Original Gas Hose Austin Healey 12
LAW75 Gas Odor Elimination Austin Healey 3
B TR4/4A GAS TANK FELT Triumph 14
Hamish Racing General Tech Petrol/Gas with high ethanol Triumph 3
edkap2002 TR6 gas smell Triumph 8
R TR2/3/3A Gas pedal pad for TR-2 Triumph 3
B Damaged threads in the gas tank Austin Healey 7
BierRunner TR6 TR6 Gas Pedal Triumph 4
Jim_Stevens Off Topic Ethanol-free gas link Triumph 1
J TR2/3/3A TR3 gas tank mystery Triumph 5
Rob Glasgow New Gas Tank Austin Healey 8
T For Sale TR2 - TR3 Gas Cap for sale Triumph Classifieds 1
B TR4/4A Gas Tank color? Triumph 4
B BE vs. Later Model Gas tanks Spridgets 2
B How to clean the old gunk out of a Spridget gas tank? Spridgets 21
JPSmit Fuel line - gas tank question Restoration & Tools 5
Ripper01 SOLD-TR6 Gas Tank Triumph Classifieds 3
A Wanted Gas tank for TR6 Triumph Classifieds 5
J For Sale Triumph Tr 2/3 Gas Pedal Triumph Classifieds 1
T TR6 My '74 TR6 Zenith Stromberg Carbs Float Bowls Leaking Gas Triumph 11
D What's inside the gas tank?? Spridgets 13
C TR2/3/3A Gas Line Triumph 11
A TR2/3/3A Interior rear panel covering gas tank and rear seat bottom install. Triumph 7
S TR2/3/3A TR3 gas filler cap Triumph 1
J TR2/3/3A TR3A gas tank repair Triumph 4
longbridgehealey Fuel pump racing, no gas Austin Healey 26
Rut MGB Running out of gas symptoms MG 21
T TR2/3/3A TR3A Gas Cap Triumph 15
D Gas Pedal Pad Jaguar 7
K For Sale TR3 Gas Cap Assembly Triumph Classifieds 0
T magnets and gas tanks, and other applications Austin Healey 3
Michael Oritt Gas cap parts now in tank Austin Healey 17
Rhodyspit75 Bonnet gas struts Spridgets 5
K TR2/3/3A Gas Gauge sending unit "float" orientation? Triumph 5
K TR2/3/3A Gas tanks...two different types? Triumph 5
ckeithjordan TR2/3/3A Gas Filler Cap Triumph 1
R TR2/3/3A Installing gas tank Triumph 6

Similar threads

Top