Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

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SinusoidalTendencies
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Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by SinusoidalTendencies » Thu May 23, 2019 1:28 am

soooo. can a flooded float bowl cause rough over rich conditions?

can a mechanical pump put out to much psi? or was the last pump so weak i never noticed the float was set wrong?
i got the Delphi pump off rockauto

got her all back together after replacing fuel pump, dizzy, starter, front struts, cv axles. drum brake cylinders, & front brake lines.

forgot to start from TDC, so dizzy was off, corrected and went to set advance to 10 btdc. set it but with difficulty maintaining a running idle.
bowl is flooded now. thoughts?

could my float and idle speed have had slack in them from adjusting to the older parts?
and so now i need to re-set the float and adjust my idle?


have till noon to figure this out
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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by jimcrazy » Thu May 23, 2019 4:11 am

if you have had the top of the carb off there is a small o-ring on the primary small ventury,,if that is left off it will act like its flooding and will ldle like shit,,happened once to me found it down in the carb
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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by Petros » Thu May 23, 2019 11:49 pm

bad float or leaky needle valve in carb will cause it to run rich and flood. it needs to be corrected. usualyl you can take the top off the carb (watch out for the tiny parts, if you drop any you many not find them).

you likely knocked loose something in the fuel line that is now blocking float valve open. I have found usually just carefully flushing/blowing out needle valve returns it to operation. I have never had to replace one yet. Usually required you to remove the top of the carb, no need to remove the carb from the engine, youi can pull off the top with the carb installed. mark all the vac lines so they go back on in correct place, and again, be very careful with the tiny clips and parts so you can get it back together.

not likely the pump is putting out too much pressure, after market pump should match factory pressure output spec. Likely the needle valve is leaking for some reason, usually crud or grit caught in it.


Hope you figured it out.
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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by SinusoidalTendencies » Tue Jul 02, 2019 7:05 pm

the ventury o-ring was out of place. still dialing it in though as i am continuing to have fuel delivery issues. on my second pump now.
it appears to still be running rich causing harder flooded starts. but it is also haveing issues sucking fuel. i can physically suck it with minimal effort if i pull the main line off the pump, but the pump can't. replaced all the fuel line. dropped and inspected the tank. checked the return line, which is somewhat difficult to blow through, but air does pass through it. replaced the evap lines, bypassed the evap solenoid. and still ended up having to install an in line electric pump between the filter and the pump so i could get it off the road where it had died on me.

any ideas on that?
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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by Petros » Tue Jul 02, 2019 8:40 pm

usually the mechanical fuel pumps are reliable and never give you trouble. a tiny leak in the fuel line up stream of the pump can cause it to suck air into the line, and it may not show a leak. so you get not enough fuel to the carb.

It is not likely the fuel pump is causing the flooding, as to why you are not getting fuel up into the pump, hard to know but if the fuel filter is clear, the only other thing that might cause it is a leaky line. There is a small screen at the fuel inlet in the fuel tank. if larger particles are floating around in the tank they can get sucked into the inlet screen and slow fuel supply. that will not cause it to flood, but be fuel starved.

it is easy to inspect the fuel inlet screen, you pull back the carpet in the back and remove a hatch on the floor of the rear storage compartment. that exposes the top of the fuel tank and the sender. you remove the sender unit and than inspect the inside of the tank with a flash light, you should be able to see the inlet screen. Usually it is clear, but rust or contaminated fuel can allow debris to plug it up.

be careful, inspect tank outside with a fan blowing, you will allow fuel vapors to fill the inside of the car. no power tools or even lamps with extension cords, (nothing that can arch or spark), battery powered flash light only.
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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by SinusoidalTendencies » Tue Jul 02, 2019 9:01 pm

like i said though. inspected the tank already. basically exhausted every option before installing an in line electric pump as an assist to the mechanical one
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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by BaileySims » Wed Jul 03, 2019 6:51 am

Sometime yesterday I watched a video on why return lines are of the utmost importance. If you are having trouble blowing through it, I would start there. He had a valve on the return line and closed it and it seems that you are having all the issues he had until he opened it. Check it out, I'm horrible at explaining things.

https://youtu.be/7svmL2mfpKE
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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by NWMO » Wed Jul 03, 2019 8:20 am

SinusoidalTendencies wrote:
Tue Jul 02, 2019 9:01 pm
like i said though. inspected the tank already. basically exhausted every option before installing an in line electric pump as an assist to the mechanical one
ST,

I'm sure you will get it worked through and I've been in your shoes (not the exact same issue). If the lines are in acceptable shape and clear, the stock fuel pump provides ample fuel/pressure for the carb. I would start with a piece of hose on the mech fuel pump and see how much fuel it kicks into a gallon jug, etc. while running (just set up a little gravity fuel feed for the carb). If you fight getting it started with gravity feed, you know there is a carb issue and will have to solve it first to test the fuel pump. Float and needle valve are the obvious starting points.

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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by SinusoidalTendencies » Wed Jul 03, 2019 2:51 pm

ok. so to fill in some trouble shooting info.

before the electric pump got added for assist, i fed the mechanical pump from a cup which worked immediately and emptied the cup in about 30 seconds.

i had just installed the new fuel filter (a clear wix) so was able to visually see it not filling hooked up to the mech pump. as well as see it fill when i sucked on the hose to the pump myself.

i think i'm going to go over the return line as that sound like the best place to start since carb issue is somewhat ruled out from the cup test (though i do think i may be having choke lagg issues, but that's a different problem)

also though, you cannot blow through the evap charcoal canister. not sure the overall signifigance of that but figure since it is a vent to the tank could very well put it under vacuum not allowing any flow until the vacuums psi is over powered.
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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by SinusoidalTendencies » Sun Jul 07, 2019 5:50 pm

blew out the lines (not a good idea while their still hooked to the tank). and deleted the assist electric pump. started fine but only ran till the bowl was empty. re-installed the electric assist pump so i could drive her around again. visually saw a vacuum bubble form in the filter that would get bigger or smaller depending on the pull from the pumps. the tank is definitely still under vacuum.
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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by Jarf » Mon Jul 08, 2019 9:34 am

I had one Terk with recurrent fuel starvation issues, it ended being the expansion line (traverses the rear frame member, on the vent line) its full width of the underside of the car, does a U-turn and goes back over to the tank.
My symptom was just like running out of gas after awhile, drove me nuts cause it looked fine but was sucking air thru the rust on the backside of the steel line where it touches the frame.

Now I am very old and not up on the latest technologies, but I have never heard of a "vacuum bubble"
To me, a bubble in fluid being drawn from a closed tank could only be caused by sucking air in, somewhere along the route.
The only other question would be is the cap working correctly?
If it isn't venting air in, the eventual suction on the tank will overpower the mechanical pump.

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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by SinusoidalTendencies » Mon Jul 08, 2019 4:09 pm

the whole vacuum bubble thing is me describing what i'm witnessing occurring. with a tank under vacuum, i can only theorize that the bubble created in the filter is also under vacuum. which is why it disappears when the car is turned off. the vacuum created pulls in fuel when there is no longer pull from the pump.

if it was sucking in air then this would not occur as there would be no vacuum to pull any amount of fuel into the filter. and i would think there would be little bubbles in the fuel instead of one big bubble that gets smaller whenever the bowl is full.


can anyone tell me more about how the evap system works? if it could cause such a problem. i've heard the evap solenoid can cause these symptoms as well. (though i did bypass it with no effect)

i'm about to just get a new line cap for the tank and run whole new lines. but i guess i might as well get a new gas cap first and see if that helps.

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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by SinusoidalTendencies » Tue Jul 09, 2019 10:45 pm

replaced the gas cap. now the bubble doesn't go away. i'm stumped.
also took the evap canister out before that and made sure air passed through everything. it passed air at a controlled rate of probably 4-8 psi.
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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by Petros » Tue Jul 09, 2019 11:04 pm

go read up on the operation of the evap system in the factory service manual, I think it is in the emissions control chapter (or perhaps the fuel system chapter). it is not too complicated, there are some simple test you can run as well, as I recall, no special tools required.

I want clarify on the air bubbles in the fuel line: a small partial leak will allow air to get sucked into the fuel lines when it is running. it limits the amount of fuel available and can make it stall out at higher rpm/power demands, but it may idle and run normally. it will not cause flooding of the carb. A large leak will suck only air and will not allow enough fuel for it to run.

flooding of the carb comes from only a few sources: fuel over pressure (not likely with a stock mechanical fuel pump), a leaky AAP (check the vac line for leaking), or a bad needle valve or float in the carb. Malfunctioning choke, that stays closed when warn (easy check, pull off the air filter when it is warmed up and inspect the position of the choke butterfly). It is also possible, but not common, that the fuel metering rod in the carb is gooped up and allowing too much fuel to pass into the intake, or some other internal malfunction (like a stuck internal check valve) that can result in too rich a mixture. Cleaning out the carb with carb cleaner usually take care of that.

if the fuel cut off Solon is malfunctioning, it usually results in that it will not idle because it is cutting off the idle fuel supply. and no linkage adjustment, no matter how bad, will result in flooding.

Are you sure it is flooding? what exactly are your symptoms? what does it do when both cold, and after warm up?
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Re: Situation... flooded float bowl & rough unsustainable idle after new pump/dizzy/starter

Post by SinusoidalTendencies » Tue Jul 09, 2019 11:38 pm

i should of started a new topic for this Petros

i'm a bit further along in figuring out the weirdest fuel issues.
now we are experiencing fuel starvation...and flooding(occasionally)
the tank was appearing to be under vacuum
pump couldn't pull hard enough. could manual pull fuel through the line.
pump would run off a cup of gas fine till it was gone of course.

replaced soft lines in bay and at tank
replaced filter
dropped and inspected the tank (i was surprised at how spotless it was on the inside)
blew out lines with air compressor
bypassed evap solenoid
had to install an electric in line to assist in pulling any gas so i could drive home (actually i went to some hot springs)

at this point i was noticing the air pocket (just one solid bubble, gas not aerated) in the new filter would change in size, bigger to smaller.
i theorized it was literally a vacuum pocket that was getting smaller by pulling in more gas as the pull fluctuated from the pumps, but what do i know.

now i've replaced the gas cap and the pocked no longer fluctuates.

but the assist pump is still needed
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