Lotus Elan and Lotus Elan Plus 2 Forums

Can anyone help me with any information to point me in the right direction to identify which model / specification of carbs are supposed to be fitted to a 1970 S4,
The car currently has fitted two 175's but which type, I am trying to get them overhauled and set up to original specifications as they are both running very rich. If anyone knows of any specialists in the leeds area it would be of great help.
Many thanks in advance
Simmo

They should be CD-175 SE. You can get a rebuild kit and do it yourself. The best place for info and bits is www.burlen.co.uk who still make new ones. You should also replace the jets and needles. They are easy to set up if you have access to a wide band lambda sensor, a basic CO meter would also do the trick but is not as good. PM for more info if you want.

Take the cover off the carbs and pull out the piston. Examine the needle where it sticks out from the piston. The base of the needle (the thick part) should be flush with the bottom of the piston or projecting about 1/16". If it is indented you will run rich.

There is a set screw that will release the needle and allow you to make this adjustment. If the needle is stuck, soak it in carb cleaner for a few days.

Worked wonders for my 69 S4 which was also running rich.

Steve B

Is there any chance that the strombergs fitted to my elan would have the adjustable needles? I have had a look down the centre of the piston and there appears to be a recess to take an allen key and the top of the piston has two slots to prevent the piston turning whilst adjusting the needle.... or is this a standard feature across all of the strombergs? Any help would be gratefully received. Thankyou all in advance

Yes, they do have adjustable needles. There is a little tool that is a long allen key with an outer barrel that locates on the two slots at the top. This stops you turning/tearing the diaphram. There are two versions of the tool. One has a little metal jobby on the end for later type carbs. I found one in a 70's time warp shop. This is just friction fitted on the allen key. I bought one of these and pulled the litte end off. Same tool!

Triumph TR men use lots of strombergs. If you go on their sites you will likely find the tool & all manner of advise about converting from fixed to adustable needles etc etc . If I have the old packet I will post the part number. I may even have two tools ( cant recall)

Mike

Thanks for the speedy reply! If you do have the part number that would be great, but don't worry too much I am sure I can find/manufacture something that will do the job, I shall take your advice and look round the triumph sites.

Summo,

The adjustment tool is B 20379Z, but I found a source of Taiwan knockoffs for $10.