Club 80-90 Forums

Just had my Pierburg carburettor reconditioned - I have fitted the carburettor and connected fresh hoses and a new fuel pump . Tomorrow I hope to get the carb working and van running … However to be honest I am bricking myself!!!! I have limited mechanical knowledge and don’t fully understand instructions that came with the recon carburettor.

So could you let me know if I am about to do something horribly wrong
Sorry its so long winded.

Following instructions I intend to:

1st leave plastic cover on top of carburet un-tightened to allow air in the system to escape and correct water flow through choke unit.

2nd Setting choke flap
With engine off - slowly depress throttle peddle to floor and then raising slowly.

3rd I am then told to disconnect the following:
a) throttle linkage – have no idea why???
b) air filter.. it says to plug the end of the vacuum hose temporarily
c) electrical connection to the choke

Question 1a) is the vacuum hose the large opening to the plastic thing that sits on top of the carburettor.
Question 1b) If so could I stuff it with a rag… or would the carb suck the rag in
Question 2) excluding the earth - there are two electric cable that come off the carb - should i disconnect both
Question 3) what is the purpose of disconnecting throttle linkage?

4rd Filling float chamber with petrol:
Turn the ignition key for about five to ten seconds – DO NOT operate throttle lever

A neighbour (with lots of t25 experience) suggested runner fuel pump inlet hose into a container of petrol so that pump did not have to work so hard …
Question 4) is this sound advice?

5th reconnect electrics and solenoid valve and choke.
Then operate the throttle level to reset the choke flap…

Question 4) This is the first time that the instructions refer to a solenoid valve?????? Any ideas what it means

Question 5) I am confused about throttle lever - at no point am I told to reconnect linkage and i sill cant see the reasonl purpose for disconnecting this in the first place??
Any ideas?

6th START VAN AS NORMAL

7th allow to run for 5-10 sec at high idle speed - then blip throttle peddle .. with cause the idle speed to drop and then progressively drop to a more normal speed as the water heat up.…

thats all - sorry that its so detailed …

Cheers Darren

1st leave plastic cover on top of carburet un-tightened to allow air in the system to escape and correct water flow through choke unit.

2nd Setting choke flap
With engine off - slowly depress throttle peddle to floor and then raising slowly.

3rd I am then told to disconnect the following:
a) throttle linkage – have no idea why???
b) air filter.. it says to plug the end of the vacuum hose temporarily
c) electrical connection to the choke

Question 1a) is the vacuum hose the large opening to the plastic thing that sits on top of the carburettor.
Question 1b) If so could I stuff it with a rag… or would the carb suck the rag in
Question 2) excluding the earth - there are two electric cable that come off the carb - should i disconnect both
Question 3) what is the purpose of disconnecting throttle linkage?

4rd Filling float chamber with petrol:
Turn the ignition key for about five to ten seconds – DO NOT operate throttle lever

A neighbour (with lots of t25 experience) suggested runner fuel pump inlet hose into a container of petrol so that pump did not have to work so hard …
Question 4) is this sound advice?

5th reconnect electrics and solenoid valve and choke.
Then operate the throttle level to reset the choke flap…

Question 4) This is the first time that the instructions refer to a solenoid valve?????? Any ideas what it means

Question 5) I am confused about throttle lever - at no point am I told to reconnect linkage and i sill cant see the reasonl purpose for disconnecting this in the first place??
Any ideas?

6th START VAN AS NORMAL

7th allow to run for 5-10 sec at high idle speed - then blip throttle peddle .. with cause the idle speed to drop and then progressively drop to a more normal speed as the water heat up.…

1st Well I don't really understand what this is about, just connect all the hoses , there is so little water loss (as long as you didn't let it run continuosly from these hoses it will self bleed, just top the coolant up if needed.

2nd Setting as in...allowing the bi-metalic spring to rotate the stepped cam....just depress the throttle once but as the carb is empty of fuel anyway you are not going to flood the engine so it doesn't matter how many times you operate the throttle at this stage.

3rd
a.. I guess so the throttle cable free play is only set when the choke is completely off (engine warm) otherwise you run the risk of the throttle cable being tight propping up the idle.
b.. Just do as it says with a screwdriver or similar to stop vacuum leaks
c.. So the electrical heater element doesn't heat up pulling off the choke before petrol has even got to the engine.

1a...no...a small bore cotton braided hose that fits to a brass pipe outlet on the lower body of the carb.
1b..no...as I said, small bore so with a smallish posi screwdriver or similar
2..if they were connected before then yes but bare in mind 'c'
3..explained in 'a'

4th..Short 5 second cranks so you don't over heat the starter, may take 3 or four times before petrol fills the carb.
Pumping the throttle once the carb is full of petrol will cause the accelerator pump to squirt excessive amounts of petrol down the venturi with the posibility of flooding.

5th..re-connect when warm and set a small amount of play in the throttle cable, making sure the throttle butterfly returns to the throttle stop screw (don't mess with the throttle stop, it should have been set by the refurb guys) idle is only set by adjusting the large air by-pass screw.

6th.. yes indeedy....allowing it first to fast idle, touching the throttle every 10 seconds or so to release the fast idle stepping until eventually (after several minutes) the choke is fully open and the revs drop to 'normal idle' (actually it might be a bit lumpy until the engine warms up)

7th..as I said in 6

What remains now are:
To re-connect and refit everything (vac hoses, breather pipes, air filter housing on top)
Refit throttle cable/linkage as described with free play

Set idle with air by-pass screw (big single slot screw)
Set CO by ear.......(small screw adjuster around the base of the carb) screw in until the engine starts to missfire, then screw out about a quater of a turn (so it idles smoothly).....CO should be setup on a gas analyser but an expert ear can normally get it to within half a percent.

Note* without actually seeing the carburettor model/type I have generalized so forgive me if some details aren't 100%

Martin