gas/mileage issues in my '83 240 dl, B21A single carb engine

[sergitin32]

Hi there Bill and friends of this matthew's forum.

So I just managed to buy a new needle today, was hard to track it down but i made it, was spensive but i managed to get it anyway.

So guess what? i put the needle and did the al adjust in the carb... the car is running nice, and i did found out finally!!! that the funny secret phantom screew DOES regulates the idle, seams the time we tried before the vacum system with lots of tubes were plugged, and i remember unpluggin lots of dirt out of the EGR system, and now i think thats the conection, the gasses come from the exhaust, into the EGR, to the vacum amplifier and then into the intake through this funny screw... so, finally thing are working, tomorrow i will install the tube that takes the gases from the exhaust to this recirculation valve, since mine is cracked and that leak can make the system to work not properly, thus the NOx higher than the usual.
And I was wondering why i cant pass air care test... and its always the NOx!!!
Hopefully with this tube done and the carb adjusted i will be done for this test...

Hey Bill, how can I post some of the info i just recopilate for Stromberg Carbs? can I upload pdfs or word files to the forum? can you? just so more people can read them all together... I also found a chapter on Haynes manual, I turelly dont know why i never see it there before, bizarrrroooo!!!

cheers, have a great one!
sergitin.

[billofdurham]

Progress at last! Air Care next stop.

Bill.

[sergitin32]

Hey Bill, I know i kinda have the car around the right point, not too rich but not lean... but still i've ben thinking and looking for that Color Tune tool you mention me for the first time, and i can't find anybody selling them here for a reasonable price... I have only look online, but i will try phisical locations tomorrow. Is there any brand you could think off, like some mayor one I should give a try first?

I know with that tool it would be sooo much more eassier!

I already ensamble the tube i need fot the exhaust recirculation system, so this would help even more with the NOx...

I hope passing this time, and if not, i will just play with the needle and pass again... some how i dont think i would have to do so much adjustment... with the digital caliper and knowing exactly how much i move the needle and the prompt results i will be able to pass it at least at the third time... lol.

Hey you told me to send that info to Matthew's email, but I dont have his address, so could you please send it to me?

thanx alot,
have a good one.
sergitin.

[billofdurham]

This describes the tool I mentioned. The original was made by Gunson but there have been others. You may pick one up on eBay.

http://www.nepeanclassic.com.au/pages/colortune.htm

For Matthew's email address click on 'memberlist' above and he is #2 on the list. You can link to his email from there.

Bill.

[sergitin32]

So Bill, now i had finally passed air care, isn't it great!!!??

The real reasson was the EGR system was completly faulty, plus some wrong hoses conection i made in my ignorance of this system at the begining teasing with the wole engine...
I fixed the valve that was stucked, welded a hole in the tube coming from the exhaust, and did some small cleaning in the vaccum amplifier and hoses with air.

So all its working well and aircare is history till next year.

Anyway there are three things i have not clear with my carb after i read all this docs (i havent been able to send them on email to matthew) and these 3 things are:

1- If the screw on top of the manifold is the fast idle adjust screw, then whats for the one next to the temperature compensator, it's named in the Haynes as the idle trimming screw... any suggestions?

2- Is it possible the new needle has not the same tolerance of the old jet and i have to purchase a new jet? Since i can't go leanner, and the car keeps running a little rough at idle, and when I lift the air piston valve the idle goes really down, meaning its too rich, but the needle is all the way out, soi can't go leaner... still have to look for intake leaks, but the vacum gauge says its ok... but still i might try looking for them one of these days.

3-Maybe i should first fix the nipple linked to the hose going to the warm start valve, is the one got broken in the connection plate by the carb... since i realized this air way enters through the temp compensator and the before mentiones idle trimming screw, are this two devices relate in some mechanism beside the warm starting?

think thats it but i am sure there must be more to ask, i just dont remember now , ejejejej...
thanx for everything, have a nice day.
Sergio.
PD: This time I might just take it to some mechanic to adjust the Carb... darn!

[billofdurham]

Congratulations. It has taken some time and, no doubt, some bad language but you have made it. For perseverance we must give you 10 out of 10.

As I said in an earlier post the screw in the top of the manifold is usually associated with the later Zenith carb and it is recommended that it be used for the idle adjustment on that one. You could try adjusting on both to get the best setting. This could also be connected to the point in question 2. If you bought the jet by quoting the carb model it should be correct but you need to bear in mind that other parts of the unit will be worn and you may never get it 100% correct.

As for question 3 you should go ahead on the repair to the nipple as the whole system depends on the integrity of all parts to operate properly. If you are drawing air in to the carb by an incorrect route it can only have an adverse effect.

This time I might just take it to some mechanic to adjust the Carb... darn!

Sort out the nipple and take it to somebody who has the necessary experience and equipment to set the carb as near as possible to factory standards. It may cost a little money but will improve your fuel consumption and the performance of that very good looking car.

Now, after all the very hard work and long hours you have spent getting it right, you can enjoy using the car and look at it with the pride that comes from a job well done.

Bill.

[sergitin32]

I shall do as you say... thanks lots.
hope God rewards you as you deserve!
have a good one
sergitin.

[sony2000]

Some thin oil in the the top of carb, and the bolt NOT touching the cam. Start the car and with the mixture screw only, set the car running at 400-600 rpm, as lean as possible. Then add 1/4 turn rich. Now use the bolt to the cam to set your idle at 800rpm. That carb could use a good spray of carb cleaner into the venturi with the car running. The mixture screw is the brass one beside the rectangular white plastic at the base of the carb.

[billofdurham]

Agreed that this is the easy way with the SU carb. However, this one has a Stromberg which needs a different approach.

Bill.

[sergitin32]

Hi there, yes the eassy way to fix the mix on the SUs has not much to do with my carb, sorry, thanks for the help anyway.

I just got fixed the nipple issue on the connection plate that leads the hose coming from the warm start valve into the temperature compensator , now for sure it starts better.

Still the idle is a little huntin... like not smooth and stable but like occilating up and down... One of the factors to considere for this is my distributor has some minor play and when i do the timing, the mark on the belt is kinda wide and blurry, never neat and steady. So I was thinking, its not stalling, I might run it like that for a while, check for gas mileage again and rethink this whole business... Still might look for some intake leaks tomorrow on my day off and play a little with those two screws of idle adjust to see what i get... also will re-check the timming and, damn something else i was supposed to do and just dont remember now... It will come back to me jeejje and i will write it down... OK I got it, i will check compression and vacum just as an extra overhaul aproach.

Thanks lots as ussual for every little write here.
I think this might finish this thread?? Isnt it?
Or I might just post later with some gas/mileage improovements hopefully.
sergitin.