carburator setting

Good evening,

last week I had some intense cleaning, checking and belt changing and so partially dismantling of our very early Dino. Unfortunatly the engine is not running as it did now. My first guess is that it could be the carbs, as they were out of the car as well. I have a service manual but unfortunatly without any settings for the carburator. As Weber is probably not too different from model to model I opened the mixture screw by 1,5 turns.

Normally nothing I can not solve (as I did in the past), but I would like to drive it into the weekend tomorrow. So I would be very thankful for any advice where to start!

The engine runs nice on idle, but is very weak the moment I want to drive. I think it night not close enough and so maybe run to lean...

many thanks,
Thomas
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The OM for your version 246 has a good listing of the carb pieces/settings.

The taper/shape of the mixture screw ends also varies so better to go from fully-closed (and that cylinder not working at idle), and then slowly open the mixture screw until that cylinder does start working at idle, then add maybe 1/4~1/2 turn more to learn what the general number of turns open from fully-closed should be for your particular hardware.

However, the idle adjustment really only affects idle. At larger throttle openings, an incorrect idle adjustment shouldn't matter much, so your report of "very weak" (something affecting all cylinders) seems more like ignition. Have you put a timing light on it to confirm the advance mechanism is working and the rotor phasing is good over a large RPM range?

 

unfortunatly I do not have the OM...

Of course it could be the ignition as well but as it ran good before I do not think so. Yes, it was taken out as well, but I marked the exact position and refitted it just the way it was.

 

Find attached fyi a procedure from Superformance regarding settings of your Weber’s. As other have mentioned, it is limited how much influence the idle mixture setting can have on your overall engine performance. Suggest you check speeder link system, cable configuration and ignition timing before spending too much time on the Weber’s.

Best Peter
View attachment carb-synch-idle-tuning-40dcnf-carbs.pdf

 

Good news; the car runs ok. Yes it was some ignition thing - I treated the wires with contact spray and changed some things at the carb and it does gods. Rest will be done tomorrow morning.

many thanks - I'll let you know how it really worked and pos some pics in "did you drive ...."

 

.
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woah that is a cool trailer

 

Yes, nice trailer! Who makes it? Model?

Freeman

 

And how much does it weigh? What vehicle are you using to pull it?

 

This looks like the trailer. I don't see any dealers in the U.S.

Trailer Range - Brian James Trailers

I'm sure a few people would be interested here!!

Freeman

 

sorry, I was not online.

yes, it is a brian james trailer. They offer lots of different sizes and models. It has about a ton and 2.700 total weight. I use a Volvo XC90 to pull it - with max. 2.700 kg pulling weight.

Trailer is wonderful! I can highly recommend it!

Btw. I changed the sparkplugs but the problems remains the same. I do have ignition on all plugs but probably not good enough for two cylinders. yin fact two plugs remained clean. after cleaning the contacts there is one left. The car is widely untouched so it seems to be the original wires, and they have some corrosion on the sparkplug

for now I think I was just carrying the Dino around...

bw,,
Thomas
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Heureka. I took wheel and wheelarch off, unscrewed the distributor cap, cleaned it, fixed it together and boom. all six!

many thanks again,
Thomas