Help me ID these IDF 40's

[RoyBatty]

Hi all,
I just received this pair of idf 40's from another forum member and would like some input from those of you who know a bit more about these carbs as they were installed to the 1600 coupes and spiders.
FIrst off, these are a bit different than the economy kit I got a couple of years ago from Auto Ricambi. Which by the way are still running great on my 1800 spider.

The emulsion tube assy is considerably shorter than the newer units on my Spider. Should I consider changing to the newer type if that is even possible?
Also, the top air horns which I have seen in the drawings and in other pics of these carbs did not come with them.
I didn't see this as a deal killer. Was I wrong? Should I look to purchase some if they can be found?
Also, I noticed the cold start system is on these carbs. After a little research I found that they are actually a pair of enrichment jets and circuits that you activate with a manual pull cable, Instead of restricting air flow like a choke butterfly that I am more used to seeing.
Well here they are.

[carl]

They look like the IDFs that came on spiders and coupes in Europe. You should be able to buy the air horns or just get some velocity stacks (same thing).

carl

[131]

I can't see it in the photos, but they should have 40IDF13/15 stamped into them somewhere, I can't remember where. They're what I've got on my car. I have seen the air horns for sale on Ebay, not often, but they are around. I believe the brass tubes poking out the top are for adding fuel at high revs, so may work best with the original air horns rather than generic velocity stacks. I haven't got the cold start enrichment circuit hooked up on mine, it starts fine on the accelerator pump, can be a bit cantankerous when it's cold, but calms down by the time I get to the top of my street, about 400m.

[JerryH]

My car has a pair of those. I use standard lunchbox air filters (no air horns--I wonder if my performance would improve with stacks installed?). I never did hook up the cold start mechanisms. When the engine is cold I use the throttle knob below the dash to increase the rpms a bit until the engine warms up, then it idles just great. I really like these carbs--they were a PITA to get set operating correctly (the PO had the linkages set so one of them didn't engage the idle circuit--it took a while to figure that one out), but now they run great and I haven't messed with them in years (apart from occasionally tweaking the idle screw).

Purchase a rebuild kit for them. I got mine from webercarbsdirect.com. Take them apart (one at a time--you can use the other one as a reference if you forget how it goes back together), clean em up, install the new parts from the parts kit, adjust the floats. Then put em back together. The forum experts recommended I purchase a synchrometer. I purchased one along with a single velocity stack (so I could connect it to the carb and clear that top tube). I found that the carbs were already well balanced. There are procedures available on the forum that describe how to adjust the fuel mix.

Good luck!

[RoyBatty]

I finally took a gif close look after talking to a tech support guy at pierce manifolds.
It turns your that one is marked as an idf40 13 and the other is stamped idf40 14.
What's the meaning of the 13 and 14?

[131]

What's the meaning of the 13 and 14?

The original 40IDFs on the 124 BC coupe were 13 and 15, the same except for the synchronising linkage in the centre, so one is front carb, the other rear. Never seen a 14.

[RoyBatty]

Thanks guys,
I have verified the "14" number on the one carb. Both carbs are metal impression stamped on the float chambers with their respective id numbers.
I used a little red scotch brite to clear up the stampings so they could be more easily read.
They are properly set up with the spring loaded clamp linkage in the center from the factory.
Need to get a set of rebuild kits for them.
I have already installed the correct jets for the 1600 in my coupe.
Can't wait to get them installed.

[amawds]

They're crap. I'll take them off your hands for the cost of scrap and I'll even pay shipping because I'm a nice guy /sarcasm
Seriously, good find. I need me a set of duals soon.

[RoyBatty]

That's really nice of you.
Hey, tell ya what. Let me first clean up the carbs and manifold, and install the new gaskets, needle and seats and such. Then I can ship them to you at my cost just to get this crap off my hands.
How's that sound?

[fiat218]

They're crap. I'll take them off your hands for the cost of scrap and I'll even pay shipping because I'm a nice guy /sarcasm
Seriously, good find. I need me a set of duals soon.

messaged you