More and more Varajet stuff.

[85berlina]

Hi Guys,
I have another varajet problem and I was wondering if any of you guys that are very familiar with these things would be able to answer.

I had my carby tuned a few weeks back by one of those dedicated carby places. To start the car, you only have to push the accelerator to the floor once and release it. Then you start the engine and it will start instantly. The engine will run perfectly for about 10-15 seconds or so and then start to make a chugging sound out the exhaust. It will occasionally blow some black smoke and the engine runs a bit rough. Once the the carby has come off its choke after a few minutes, it runs perfectly without a problem and accelerates great.

I took it back to them and they have backed the choke adjustment off and it hasn't done much.

Would it be the choke adjustment or could it be something like the float level or something else again.

Thanks guys

 

[vkberlina]

Need more info about the engine & carbie.

Are you running the EST system or HEI Dizzy?
Is the engine stock or modded?
Did they use standard sized jets etc or different?
Is the car an auto or manual?

cheers
scott

 

[Goon]

Have u done basic maintence stuff recently? eg. spark plugs, leads, oil change etc..

Using any lube in your fuel?

Has this been happening since u had the carby tuned?

 

[85berlina]

All the basic maintenance has been done, plugs leads etc. and it was running fine except for the incorrectly adjusted carby. This has all happened after the carby has been tuned.

I do use that flashlube stuff with petrol.

The carby is the varajet 2 carby that was standard on the VK.
It has a stock black motor in it.
It is automatic.
It has a blue motor dizzy in it. The EST failed a few years back.
I guess it has standard size jets in it as it is just a stock carby.

Thanks guys

 

[atrail308]

the black smoke seems like you're getting too much fuel while the choke is on and its causing it to flood while its cold...

 

[85berlina]

I started it up this morning and got my father to have a look. He said that it was more white smoke than black smoke and that was from water in the exhaust or something.
So, it isn't black smoke after all, (Maybe, I'll be finding out soon) however, it still runs like crap during that period of time.
After I started it up today and it came off the choke and ran great, I manually closed the choke over to where it would go when it is cold and it started to do make the chugging sound again so I guess that it is choke related.

 

[atrail308]

hes right, white smoke is just condesation cos its cold and water builds up in the exhaust... it sounds like its not getting enough fuel for it to run smooothly with the choke flap closed... its been a while since i've played around with the varijet, i had a similar problem with one of my old VH 6-cyls, i ended up just ripping the whole choke setup off...

 

[Goon]

The choke is et by th e longest index mark on it, get a touch and make sure the arrow is pointing on the longest, i've replaced mine before to a VH choke.

The hoke should auto close when cold.. every start i push the pedal once and start even with the choke it it automatic starts.. it shouldnt take no longer then 3 mins to warm up with a standard exhaust.

With extractors/headers it might take 3 - 5mins.

 

[85berlina]

Does anyone elses make a chugging sound out the exhaust when the auto choke is fully engaged?

 

[Don Sutton]

The fact that the engine starts and runs OK for 10~15 minutes means that 1] the choke is closing 2] that the unloader is working.
This means that the next stage ie where the bimetal should be heating up and backing the choke off is either out of adjustment or not working.
From memory I think it was electrically heated and not exhaust heated so check that it is getting voltage supply to the connector and that the carburettor earths properly ie there should be no voltage potential between the carburettor and the battery earth other than say 0.2 volts. Also check that the adjustment of the bimetal is on the standard setting. If there is a no continuity through the heating coil then the heating coil may have died. It is common for the source of power to the heating coil to come from a special terminal on the alternator so that the choke gets heated only while the engine is running.