david brown 885 carberator info gas

davebrown

New member
Joined
Mar 24, 2012
Messages
2
Location
Nova Scotia
Tractor
David Brown 4600 Gas
Hi 59turbo

Here is basically what I went through with a David Brown with the same 34IVN carb with the same flooding issue. I Read all the forums I could find, cleaned the the carb numerous times, adjusted the float up and down, found and performed the procedure for insuring the top and bottom halves of the carburetor were flat, installed a new kit from England, made new bushings and installed new throttle shaft all not much help. I saw several posts indicating early Landrovers had a similar carbs 36IV, a cousin to the 34IVN I think they said, and then found a post on this forum from a gent in Quebec who had installed one on his David Brown with success. I found one through our local Landrover club and it worked pretty nice after disconnecting the accelerator pump linkage and plugging the vacuum connection. All pretty good. Then one day I was at a local small engine shop and noticed they had a bench top ultrasonic cleaner so I got him to put the original 34IVN through the cleaner (dismantled of course). Bingo it works like a new one. I then got him to do the 36IV as well but I have never had to re-install it. Hope this helps someone else.
 

aczlan

Super Star Member
Joined
Mar 7, 2008
Messages
17,619
Location
Northern Fingerlakes region of NY, USA
Tractor
Case 480F LL, Kubota L3830GST, B7500HST, BX2660
Does it keep dumping gas in with the tractor off?
Is it dumping black smoke at idle, when throttled up, or both?
If its just at idle, you probbaly need to close the idle jet down a little (tighten the idle jet screw). See: CARBURETOR SET UP AND LEAN BEST IDLE ADJUSTMENT for directions on how to do that or Zenith Series IV - Zenith Caburetters for the Zenith page for that model (which has a bunch on how each piece of the carb functions).

Aaron Z
 

59turbo

New member
Joined
Apr 20, 2020
Messages
3
Tractor
David Brown 885g
No gas when the tractor is off. When I throttle up is when it smokes the most. With no air intake on the carb, I can look down
the carb throat and see a heavy gas spray going in. Not a fine mist like it probably should be. The times I separated the carb halves, leaving the bowl attached to the intake manifold, the gas level in the bowl looked right.
I am going to look into the above suggestions and see what happens. If need be, I now know there is another carb I can use.
Thanks to all for the input.

59turbo
 

radios1

Elite Member
Joined
May 3, 2018
Messages
2,813
Location
Long Island New York
Tractor
john deere la145
No gas when the tractor is off. When I throttle up is when it smokes the most. With no air intake on the carb, I can look down
the carb throat and see a heavy gas spray going in. Not a fine mist like it probably should be. The times I separated the carb halves, leaving the bowl attached to the intake manifold, the gas level in the bowl looked right.
I am going to look into the above suggestions and see what happens. If need be, I now know there is another carb I can use.
Thanks to all for the input.

59turbo
the heavy gas spray is from the accelerator pump. I'm surprised the tractor can't handle that, but maybe it's for a larger engine!. the accelerator pump helps the engine accelerate, and it works great when it's properly calibrated for the specific engine it's used on, but if not, it can inject too much fuel and make the engine smoke, and lose power, it's all in the adjustment!..
 

59turbo

New member
Joined
Apr 20, 2020
Messages
3
Tractor
David Brown 885g
My carburetor does not have an accelerator pump. I just had a ultrasonic cleaning done, no help.
I also disconnected the fuel pump from the carb and fed it with a piece of fuel line, still too much fuel.
I have a local carb/tractor guy lined up to come look everything over, once this social distancing calms down.
Hopefully in the next couple weeks. Maybe his knowledge will see something I am not.
 
 
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