Need Help with 40's carbs, Old 914 FI Guy Newbie with carbs. Options

[majkos1]

am waving a White flag here.

Trying to tune Dual Weber 40's carbs,
some adjustment to all the idle screws,
about two full turns each,
fuel pressure at abou2-3 lbs,
timing at a smooth idle,
Timing marks are way off, I don't know how but timing marks are on two and four.
my guess is improper fan installation, the lil peg broken and previous mechanic threw on the impeller fan on.
#1 firing is in correct position on dist.
verify by valves .

Further hampered by ignition switch not working anymore.
after a few hours trying to figure out why switch not working,
and looking into World's file for clue,
discovered Clay advise to check via Relay board technique ,
am able to get starter to work, (Hot wire to Yellow starter wire) and go back to tune the carbs.

Carbs are still backfiring.
According to the A/F gauge , idle at 12,kinda lean
but rev motor, peg out too rich.

am praying not having to need carbs rebuild.
only history I know of, is one carb was rebuilt.

any good info will be greatly appreciated.

Two goals,
get this 914 on the road, (IMG:style_emoticons/default/driving.gif)
after 15 years on jack stands,
make debut run to Red Rocks.

[Superhawk996]

That’s a lot going on and still not enough info.

You need to resolve the timing as a first step. guessing isn’t an option.

Then you’re at high altitude which compounds tuning and means your jetting will be different than flatlanders.

Two turns out on mix screws and running lean means jetting probably is off and/or your Venturi’s are too big and you’re not developing a good vacuum signal at idle. Need full info on venturis, idle jets, emulsion tube, and main jet size.

Hopefully we can get some other high altitude guys to share their jetting.

If carbs are an unknown on the last time they were cleaned and rebuilt - that is a good place to start. Trying to tune dirty - plugged carbs will never work out for you.

[r_towle]

Pull the man jets and idle jets.
Get some glasses
Post here the little numbers on the side of each jet

Do one at a time
Remove, read, write it down, replace
This way you won’t change positions.

Where did the car come from?
Elevation matters a lot with carb jetting

[majkos1]

Great leads Guys!!
thank you

will tackle carbs now.

Correct on timing ,
guess work isn't good.

am surprise High altitude can contribute more surprise.

[rhodyguy]

What are the idle air mixture screws set to? Same ? for air by-pass screws. What are the bal tool numbers for each Venturi?

[majkos1]

That’s a lot going on and still not enough info.

You need to resolve the timing as a first step. guessing isn’t an option.

Then you’re at high altitude which compounds tuning and means your jetting will be different than flatlanders.

Two turns out on mix screws and running lean means jetting probably is off and/or your Venturi’s are too big and you’re not developing a good vacuum signal at idle. Need full info on venturis, idle jets, emulsion tube, and main jet size.

Hopefully we can get some other high altitude guys to share their jetting.

If carbs are an unknown on the last time they were cleaned and rebuilt - that is a good place to start. Trying to tune dirty - plugged carbs will never work out for you.

SuperHawk, you Nailed it.

just started to get into and discovered tons of rust/gunk in fuel line filter.
glad you mentioned geting nowhere with a dirty carb.

[rhodyguy]

Rust in the filter does not bode well for the fuel tank and the filter sock inside of the tank.