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Incompatible carb/dizzy?
geknet - May 21st, 2004 at 09:28 AM

I'm definately not very knowlegeable with engines. My only real knowledge is from reading. I managed to replace my old 1500 with a Pobjoy built 1600 a mate had in his shed for a few years but I'm having a little problem.
The original distributor didn't have a cap for a few years while it was unused and was in bad shape so I replaced it with a 009. It's also got a 34pict-3 solex carb. I vaugely remember reading somewhere that these two don't really work all that great together.
The problem I have is that when the enginge is cold, I get a bad heistation when accelerating. It will splutter and cough reall bad but a bit of a pump of the accelerator and it picks up. If I change gears and accelerate it just doesn't respond. If I leave my foot in the same position on the accelerator it will splutter and after about 5 or 6 seconds it will actually do something.
Once it's warmed up though it runs great. but this can sometimes take about 6 or 7 minutes of sitting there keeping the revs just right.
I'm a bit sus of the carb so I got it rebuilt by a proffessional. My thinking though is that it's the problem. Could it be jetting, or something? Like I said I don't know a huge amount so don't crucify me if this is sounding stupid.
thanks in advance..


Bizarre - May 21st, 2004 at 10:13 AM

sounds more like your choke isnt working.

There should be a wire going to the ceramic disc on the RHS of the carb.

Take the air cleaner off in the morning when cold.
Activate the accelerator pedal and the brass disc in the carb should move and block the choke.

Check this first.

IF it was jetting or dizzy it would do it all the time.

Just when cold sound like choke failure


mnsKmobi - May 21st, 2004 at 02:31 PM

Quote:
Originally posted by geknet
.snip.
The original distributor didn't have a cap for a few years while it was unused and was in bad shape so I replaced it with a 009. It's also got a 34pict-3 solex carb. I vaugely remember reading somewhere that these two don't really work all that great together.



This is referring to the famous "flat spot". That's not what is causing your current problem.

Quote:
The problem I have is that when the enginge is cold, I get a bad heistation when accelerating. It will splutter and cough reall bad but a bit of a pump of the accelerator and it picks up. If I change gears and accelerate it just doesn't respond. If I leave my foot in the same position on the accelerator it will splutter and after about 5 or 6 seconds it will actually do something.
Once it's warmed up though it runs great. but this can sometimes take about 6 or 7 minutes of sitting there keeping the revs just right.
I'm a bit sus of the carb so I got it rebuilt by a proffessional. My thinking though is that it's the problem. Could it be jetting, or something? Like I said I don't know a huge amount so don't crucify me if this is sounding stupid.
thanks in advance..


There are a number of systems that make the engine and carb/manifolds warm up to operating temperature ASAP.

1. As blue74l said, the choke on the carby
2. A heat riser that uses heat from the exhaust to heat the inlet manifold. They can get blocked with carbon over time. There is a description of how they work plus troublestooting/fixing at this site:

http://www.geocities.com/vwresource/heat_risers

3. Flaps that reduce the flow of cooling air when the engine is cold. These may have been disabled in some way to attempt to "help the cooling"

Your problem could be the result of any (or all) of these systems not working.

PS. It can be helpful to have your location in your profile

[Edited on 21-5-2004 by mnsKmobi]