• Hi Guest! Being a Paying Supporter is NOT a requirement to participate at BCF. However, subscribing will help ensure we can continue to serve the LBC community for years to come. If you enjoy BCF and find our forum a useful resource...Please consider supporting us by **Upgrading**
    (PS: Subscribers don't see this banner)

Stromberg Carb Problem


Jedi Hopeful
Hi All, Have a problem with the rear Stromberg on my TR4. It's leaking gas from the vent hole for the air cleaner. By this I mean the holes immediately above the bolt holes for the air cleaner. When throttle is increased gas is sucked back into carb and no leaking. Have played with both the needle and float setting but can't seem to get rid of this problem. Any ideas? Thanks, Mike

63 TR4 Surrey Top
71 MGB OD & Wires


I would be very leary of driving the car until it is fixed. I had a problem years ago that threw gas into the aircleaner and a backfire through the carbs caused a fire. A few anxious minutes followed.
Have you looked at the jet? Maybe a piece of dirt or something is not allowing it to close properly.


Jedi Hopeful
It sounds like your float valve is stuck open. Either there is a hole in your float or the valve is bad. Not a hard fix just replace bad parts.


Jedi Knight
Certainly sounds like a fuel level problem in the carb, it should be running VERY rich if it is too high, check the plugs for black sooty coatings.


Luke Skywalker
Country flag
I agree, it's more likely the needle and seat and as you can't see what's inside of the Stromberg I would change it and the other one too. Groose jets work fine, just be sure to clean them in paint thinner or some carb cleaner before installing as they come with some kind of lub on them and work after a while when enough gas runs through to wash them off, in the mean time it leaks like crazy. Wayne


Country flag
Almost 100% certain its the valve. I had the same problem on my rear carb as well on my TR4. The fact that you have already pulled the carb and adjusted the float, I think replacing the needle valve would be a good thing to do.

On my carb, it turned out that the previous owner had put the carb back together incorrectly - the pivot rod holding the float was installed backwards, allowing it to back out which jambed the float - no float, no valve and gas would fly out of the vent. Very dangerous, but doesn't sound like it is exactly your problem!

Since you didn't mention any problem with the float itself, I assume it looks to be in pretty good shape?

Similar threads
Thread starter Title Forum Replies Date
T TR6 Carb Vacuum Port- TR6 Zenith-Stromberg Carbs Triumph 2
M General MG stromberg carb MG 5
R J-H Stromberg carb connections? Where do they go? Other British Cars 2
R GT6 Carb Floats for Stromberg 150 . Triumph 5
SherpaPilot TR6 Stromberg CD 175 Carb Tuning Triumph 8
P TR6 Tr6 stromberg carb gas leak from starter valve bolt shaft Triumph 5
bighealeysource Stromberg carb help needed for TR buddy Triumph 8
H Stromberg Carb Sync and adjust Triumph 6
JPSmit Stromberg Carb Question Triumph 15
A XKE Series II Stromberg Carb Upgrade Jaguar 4
S Question on rebuilding Stromberg carb Triumph 24
T Stromberg 150 CD carb question Triumph 4
C Stromberg Carb 'O' ring Triumph 3
dklawson Improvising Stromberg Carb Tools Triumph 14
J TR4/4A TR4 Stromberg Carb Question ? Triumph 12
I TR6 69 TR6 Zenith Stromberg carb help Triumph 1
P GT6 GT6 stromberg carb question Triumph 6
SCguy TR4/4A TR4 Stromberg Carb. adjustment Triumph 12
K Stromberg carb question Triumph 4
S stromberg carb adjusting Triumph 2
johnrip Zeinith-Stromberg Carb K+N Air Filters Triumph 8
S TR6 Stromberg Bypass Valves - Question Triumph 11
T TR6 My '74 TR6 Zenith Stromberg Carbs Float Bowls Leaking Gas Triumph 11
Sarastro TR4/4A Stromberg linkage question Triumph 4
SherpaPilot TR6 Stromberg War, Finally Success Triumph 2
R TR2/3/3A Stromberg vs. SU carbs [discussion/advice] Triumph 17
D Stromberg Dash Pot Screws Jaguar 3
Merlin63Tr4 TR4/4A Cracked Zenith-Stromberg float assemblies Triumph 13
steveg Online SU and Stromberg needle database with comparison charting Austin Healey 2
B Zenith Stromberg O ring question Other British Cars 8
K TR4/4A Stromberg..."coupler" that links vacuum outlet to diff vacuum line is N/A? Triumph 3
K TR4/4A Stromberg question. Triumph 13
M TR4/4A Stromberg CD175carb query Triumph 7
RickB MGB Stromberg on my 80 MGB - fast idle this morning MG 6
RickB MGB HS6 or HIF4 bolt right on in place of Stromberg? MG 6
Zimmycobra TR4/4A Zenith Stromberg questions Triumph 13
M TR4/4A Stromberg ? Triumph 4
L zenith-stromberg carbs Lotus 11
G Stromberg cd150 question Spridgets 1
TR6BobNF General Tech Midget Stromberg 150 Adjustment MG 8
Airfix Wedge TR8 Zenith Stromberg carbs slow deceleration Triumph 1
W Weber/stromberg air cleaners Jaguar 3
dklawson Early Stromberg Floats - 150CD Triumph 5
W Zenith stromberg carbs Jaguar 3
J stromberg float source or x referance Triumph 2
L Stromberg 175 cd question Other British Cars 5
D TR6 76 TR6 Stromberg Air Valve Triumph 2
T Stromberg Triumph 22
sundown 175cd stromberg carbs Triumph 4

Similar threads