Starting issue after 2 days.

[84E24]

My 1973 3.0 cs with orginal motor and 89k miles will not start after sitting for a couple days. The carbs were change to 32/36 Webbers in 1984. They have about 65k miles on them. I have to use starting fluid to get it started but once its running there is no issues in restarting the same day or even the next. Could it be that the bowls are leaking dry in those 2 days ? Think its time to change out for new? Any ideas will help.

Thanks,

Steve

 

[oldcoupe]

Starting Issue

The fuel line drains back down and the bowls on the Zeniths seem to empty so the starter churns and churns until the fuel comes through or the battery gives up.

I did a post some time ago about this - I put an outboard motor fuel primer bulb ($6) in the flexible line where it runs along the back of the engine compartment before the fuel pump, and a few presses fill the line and bowls, and the motor starts first or second turn of the key even after standing a few weeks.

Walloth & Nesch sell an inline non-return valve, but the bulb has that, and also lets you refill the carbs.

 

[Tundra]

If you have a leak you should be able to smell it in the engine bay. Sometime ago I had a leak on my webers (same as yours) and noticed it was leaking whenever and only when I pressed on the accelerator linkage to the max. It was coming from the accelerator pump on the carburators. it was part #31 on this link http://www.carburetion.com/diags/3236DGAVDiaginfo.asp . With the car stopped, manually press on your accelerator linkage to the max a few times and see if there is a leak in the area where #31 is located. If you do, it obviously needs to be changed. It's part of a rebuild kit at about $27. per carb. This is the kit http://www.carburetion.com/Weber/weberparts.asp (CU-32k) it's now $29.95

 

[Bertocchi]

I have read some of the suggestions here and all though they are very insightful I find it difficult to believe that the float bowls empty in just two days?
What is the health of the engine itself? Compression? When were the valves last adjusted? Could there be a vacuum leak somewhere?

 

[jmackro]

I have read some of the suggestions here and all though they are very insightful I find it difficult to believe that the float bowls empty in just two days?

Agree that they wouldn't evaporate dry in as little as 2 days. But, if there is a leak, they could drain fairly quickly. I agree with Andre - if they're leaking at a rate of .5 bowl/day you should be able to see/smell it, .

Are you confident that the accelerating pumps are pumping? See a spray of gas when you look down the carbs while operating the linkage? Or as Bertocchi asks, might some other engine health issue, like compression or ignition be a factor?

 

[jranmann]

There's another possibility that's not fuel related, having to do with your secondary electrical system...

Just for grins pull off your distributor cap and check the integrity of the points themselves, (cap and rotor too) their surface condition (smooth or pitted) and the meeting of the 2 sides looks now like the point spring in there is about to let go (mis-alignment)...also the amount of moistlure in the air in Ohio is winter may have some other lasting effect if the car is open to the air, etc ... if this works to help resolve the issue just be sure you trash the dog's collar, prior to having the blizzards on old winter's menu make repairs (not to mention even getting the the garage) almost impossible.

Ran

(PS Don't forget to change the brake fluid and the coolant...)

 

[nashvillecat]

I read through the other responses and generally agree with all of them. However, if you cannot see or smell a leak near the carb bowl/s or the accelerator pump diaphram/s, why not confirm the existence of disappearing fuel. As someone else noted, open the throttle and you should see a stream of gas squirt from the accelerator tube down the primary venturi of each carb. Or, you could simply remove the top of one or both carbs and see what's what? Six flat head screws and one e clip that retains the choke rod per carb - is all that is keeping you from this.

The fact that you mention your use of starting fluid makes me think something else is your problem.

How are your chokes? Chokes and choke linkages do wear and occasionally require a little attention. (If I am not mistaken half of the spray cans that used to be on the walls of the auto stores were labeled "Carb and Choke Cleaner.") Whether your chokes are electrically controlled or heated by engine coolant, those flaps should be shut if the engine is cold when you crank it over. If the ambient temperature at Wright Pat is in line with late fall temperatures, the operation of those chokes is even more important.

Another possibility, albeit not the most likely, is worn throttle shafts. Weber 32/36's are notorious for wear there and this becomes a source for vacuum leaks. This could contribute to any poorly adjusted or partially functioning chokes.

If you can confirm that you actually have a lack-of-fuel problem, another possibility is that your float levels are set too low so that you are only filling the bowls minimally. This can also occur when the floats themselves develop leaks and absorb some fuel and - wait for it, - no longer float.

Returning to your use of starting fluid. Starter fluid works for all sorts of conditions from weak mixtures (lack of fuel) to overrich situations and - when your ignition system is weak and you are producing an inadequate spark. What is the state of your ignition system? Battery? How long since the last tune up? Coil? Condenser? Any and all of these things could contribute to hard starting when cold. The fact that it doesn't seem to happen overnight but after two days of sitting would seem to point to fuel, but strange things can happen - especially if your car is close to hangar 18! :wink:

hth and good luck!

hth

 

[JhwShark]

There's another possibility that's not fuel related, having to do with your secondary electrical system...

Ran

Adding to the electrical analysis...on the Starting circuit, juice goes from the coil + to the resistor in-line to the carb's/FI; after Start juice goes from ig switch ON to coil to the carb's on a different path.
Check the continuity of the resistor.

Jon

 

[jranmann]

Starter fluid works for all sorts of conditions from weak mixtures (lack of fuel) to overrich situations and - when your ignition system is weak and you are producing an inadequate spark.

Was just a shot in the dark but you can see that but five minutes with a flashlight will tell you if your condenser's shot, or the cap is cracked or the points have high resistance and believe it or not a small thin film of corrosion on the point surfaces can make an e9 the devil to start after the film has covered both surfaces... especially in an open garage area and if the plugs are old and rich-fouled with say aging plug wires and a weak coil...... (the buildup every couple of days is what i'm suspecting) and the starting fluid will of course temporarily remedy these issues but for a moment...at the cost of dumping more ether down the throat of the beast which is never a good thing in excess.

Anthropomorphically speaking.... surely this may be enough grief for oneself to finally tune the darned thing up to spec. and give her will to live instead of days of darkness punctuated by moments of metal grinding, oil starved, wear down the PepBoys battery terror by grinding away at the starter mercilessly antiipating the waning possibility that perhaps one or two plugs might eventually fire off? Not a wonder she resists all attempts to go out and do it just one more time after 36 years of nothing but?

lol! (apologies for the terse words meant in jest... but winter's in Ohio can be very bleak indeed can they not?)

Cheers!

Ran