DCOE rich idle - help please!

[2002Scoob]

I personally am not sure about the recommendation to disconnect the linkage....

 

I think that recommendation exists to eliminate the possibility that either the linkage is set-up wrong (then you're just going to just get into a muck when you connect it, but I guess that falls into process of elimination?) or it's not adjusted to where at a resting state you're on your idle-screw with throttle plates as close to closed as possible. 

 

I've got the semi-cheapo push-rod style top linkage people hate (but has worked great for me for 4 years now, no fiddling necessary), and with anything that requires putting torque on one end of a long stick, and having an equal degree of application of force at the other end is... unlikely. And you want your carbs to be sync'd mechanically with all factors in play.

 

So me, personally... when I mechanically sync'd my carbs, I set it up with my linkage installed, and made sure to eliminate any slop while adding a touch of pre-load to the forward arm of the linkage so that there wasn't any concern that the rear-carb wasn't deeper into the progressions than the forward carb at any given point.

 

I then double-checked alignment using my flashlight trick to confirm visual/mechanical synchronisation across the other progression holes with the linkage under load, not just the first ones. 

 

Fun fact thou.... That all kinda went out the window when I got it all installed and heat became a factor and things started to move (they do). So I ended up doing it all over again with a hot motor/linkage  

 

And maybe that's why people don't like the cheapo rod-style? That, and they say they tend to slip... but I just scuffed my contact surfaces when I installed it and added a dab of epoxy between them and they haven't budged after all these years.

 

And just for fun, here's what that first progression hole looks like against the throttle plate edge. 

 

If you've got a cable or center-pull/push style linkage, this likely isn't much an issue... but maybe worth checking? I've only had the push-rod style on my car. 

 

+1 on using a Malpassi Filter-King. That's what I've been running, and I made a custom in-line fitting for a cheapo fuel pressure gauge between it and the carbs to monitor fuel pressure. It's set to a tad lower than 2psi with a carter inline electric pump in the trunk at the tank. 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Edited May 5, 2020 by 2002Scoob

[Hans]

Nice eclipse photos!

[ibewebbman]

Well I am gaining on it! The float on the front carb was a problem that seems to be resolved now -  I do think there is something to the "plastic float in an original brass float carb" in terms of float height adjustments. Seems like close to 14 mm from the front of the float is the place the floats are roughly parallel carb top, in all the searching I did about this it seems that that was the one thing I could identify that was reasonably consistent - 12mm seem too high for what I have... thats my theory for now anyway...this might be one of the few places on this car 2mm matters ?

 

Also cleaned up some linkage issues - there was some slop in the sync levers that I needed to address - these are weber parts! I dont know if it normal to have to bend and tweak stuff on the linkage set ups, but I did, and I got it working better.

 

got it started and afr is 11.5 - 12.5! So happy to make progress - I feel like this might be successful after all!

 

SO in summary - several issues identified and addressed so far:

 

1. Fuel Pressure - running about 2-2.5lbs now down from 4-4.5 - I may try pulling the regulator out just to see if it was my floats all along or both - but I'll run it at 2.5lbs permanently.

2. Floats adjusted to 14/24

3. Lots of linkage stiction and tweaking - throttle shaft tight on one carb etc - just to be clear for those of you paying close attention - I am using @halboyleskit and all the issues I have are NOT related to his stuff. I would recommend his kit.

 

Next up - re connect all the linkage a drive it - I'll report back with AFR numbers.

[ibewebbman]

6 hours ago, Hans said:

Nice eclipse photos!

even nicer CNC!

[TobyB]

...you mean lathe.  Not all lathes are computer controlled, nor numerically controlled.

 

But I'm glad you're making progress.  It's kind of a rite of passage- you just have to 

learn your linkage, especially 'the first time'

 

t

uses his hands.

Edited May 6, 2020 by TobyB

[ibewebbman]

2 hours ago, TobyB said:

...you mean lathe.  Not all lathes are computer controlled, nor numerically controlled.

 

But I'm glad you're making progress.  It's kind of a rite of passage- you just have to 

learn your linkage, especially 'the first time'

 

t

uses his hands.

facepalm

I see it now...