vandelay industries
1/2 ton status
No the carb is completely computer free. ESC (not to be confused with CCC) was something that some (most?) 82-86 gas trucks had. And all it did was retard timing when it sensed detonation/knocking.
CK5
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Engine starts ok, but immediately stops:
- Thread starter vandelay industries
- Start date
No the carb is completely computer free. ESC (not to be confused with CCC) was something that some (most?) 82-86 gas trucks had. And all it did was retard timing when it sensed detonation/knocking.
vandelay industries
1/2 ton status
Not happy about this one bit. Then again, i never really had any experience with q-jets; i'm much more familiar with 2G's. One reason why i'm not running a 2G is 2bbl manifolds are not as easy to find for a 4.3 and i figured it would be easier/simplier just to stick with a the q-jet and q-jet manifold.
We'll continue tomorrow.
We'll continue tomorrow.
You definitely need to verify fuel supply. Squirters aka accelerator pump works so there is some fuel there.
Just for asking when was the last time it ran?
Just for asking when was the last time it ran?
vandelay industries
1/2 ton status
Well, last time it really ran was just before i bought it---i was able to hear it run in Oct 13'.
Of course, i have been "running" it for sec here and there since last tuesday.
i think we're almost there.
Small can fresh gas placed above fuel pump and plumbed in to pump for test
vandelay industries
1/2 ton status
i will do all those fuel pump tests, but first why not wait until all the fuel is gone from the bowl?
So, the only things i did today were to plug up all the open ports in the carb and manifold, advance base timing just a little bit. i'm also filling the bowl full thru the vent and pumping the carb 4-5 times (shouldn't have to do this though?) Also, switched vacuum advance to ported.
It seems like it's lasting a little longer, but still stalling out after maybe 6-7 revolutions.
So, the only things i did today were to plug up all the open ports in the carb and manifold, advance base timing just a little bit. i'm also filling the bowl full thru the vent and pumping the carb 4-5 times (shouldn't have to do this though?) Also, switched vacuum advance to ported.
It seems like it's lasting a little longer, but still stalling out after maybe 6-7 revolutions.
Actually with a quadrajet pumping is a requirement for starting, at least once anyways cold if it's been run recently.
The fuel bowl should be full with all the cranking you do.
The fuel bowl should be full with all the cranking you do.
Bowl should have some fuel in it for a few days. Enough for accelerator pump to work.
Plug open ports?
Plug open ports?
vandelay industries
1/2 ton status
Yes, i meant pumping 4-5 times shouldn't be necessary to do it that much?
i'm suspecting that it's too lean, but choke seems to be working ok AND this carb ran just fine on a 305 and a 350 at idle (forgot-- this carb was the only other thing i changed on the 4.3) More cubes to feed w/ the 305 and 350.... so if anything it should be a little rich now? The main reason why i changed carbs is the one that came with the 4.3 was a junk remanfactured unit AND i believe it's the wrong application.
Everytime i start it i pump the acc 4-5 times and it does start up easy---doesn't flood so that's another reason why i'm suspecting lean.
RE: plugged open ports:
There were a few open vacuum ports on the carb---i didn't think it was important as i'm just trying to get the thing running, but after doing some reading i found that it could really mess up your idle and cause stalling, so i plugged 'em.
i'm suspecting that it's too lean, but choke seems to be working ok AND this carb ran just fine on a 305 and a 350 at idle (forgot-- this carb was the only other thing i changed on the 4.3) More cubes to feed w/ the 305 and 350.... so if anything it should be a little rich now? The main reason why i changed carbs is the one that came with the 4.3 was a junk remanfactured unit AND i believe it's the wrong application.
Everytime i start it i pump the acc 4-5 times and it does start up easy---doesn't flood so that's another reason why i'm suspecting lean.
RE: plugged open ports:
There were a few open vacuum ports on the carb---i didn't think it was important as i'm just trying to get the thing running, but after doing some reading i found that it could really mess up your idle and cause stalling, so i plugged 'em.
If you have a "large" vacuum leak,like the PCV hose or the brake booster vacuum hose off,it'll die at idle --but you should be able to keep it running by giving it throttle....
If your just trying to run it off a bit of gas in the carb bowl with the fuel line & pump not connected,it'll probably die then too--Q-jets need at least 4 psi pressure to run correctly..one might run on gravity feed,but will want to bog and die out under a load.
If your just trying to run it off a bit of gas in the carb bowl with the fuel line & pump not connected,it'll probably die then too--Q-jets need at least 4 psi pressure to run correctly..one might run on gravity feed,but will want to bog and die out under a load.
One thing about a carb. The accelerator pump is separate from the jets. In other words, you could plug the jets which run the engine, and the accelerator would still squirt gas when you pumped the pedal.
They both feed off the bowl, but if the jets are clogged, it will crank and run for a second or so on the raw gas you pump in, but then stop.
Don't know what might have clogged the jets, unless you rebuilt the carb and used silicone rubber to replace the gaskets like I did one time.......
Car ran fine for about a hour, until the silicone squeezed out inside the bowl dissolved enough to turn loose and fall down into the bowl.
One trick you can try. If you have a propane torch, turn it on, DO NOT light it, and get someone to crank the truck without their foot on the gas while you let the torch blow into the intake of the carb.
Most engines will stumble along at idle while running on the propane. If yours keeps running, it is definitely a fuel problem.
They both feed off the bowl, but if the jets are clogged, it will crank and run for a second or so on the raw gas you pump in, but then stop.
Don't know what might have clogged the jets, unless you rebuilt the carb and used silicone rubber to replace the gaskets like I did one time.......
Car ran fine for about a hour, until the silicone squeezed out inside the bowl dissolved enough to turn loose and fall down into the bowl.
One trick you can try. If you have a propane torch, turn it on, DO NOT light it, and get someone to crank the truck without their foot on the gas while you let the torch blow into the intake of the carb.
Most engines will stumble along at idle while running on the propane. If yours keeps running, it is definitely a fuel problem.
vandelay industries
1/2 ton status
UPDATE:
The fuel pump is definitely putting out fuel as i did the container test.
i've advanced the timing a little to a lot by turning the distributor counter-clockwise although to me it looked right before i did this. Vac advance canister should be at a 45 degree angle to engine?
i think it is lasting maybe a second longer than normal which is maybe 3-4 seconds.. It also seems to be puttering out vs. just stopping abruptly.
Also, this carb was rebuilt by me in Jan 09, ran briefly and then put on the shelf. i decided not to run it because the 305 that i was swapping in had a 2G and i didn't feel like changing manifolds and i'm kinda glad i did because i learned a lot about 2G's. After i rebuilt it, this quadrajet ran ok on a 350 So i'm thinking/hoping the carb isn't the issue here?
The fuel pump is definitely putting out fuel as i did the container test.
i've advanced the timing a little to a lot by turning the distributor counter-clockwise although to me it looked right before i did this. Vac advance canister should be at a 45 degree angle to engine?
i think it is lasting maybe a second longer than normal which is maybe 3-4 seconds.. It also seems to be puttering out vs. just stopping abruptly.
Also, this carb was rebuilt by me in Jan 09, ran briefly and then put on the shelf. i decided not to run it because the 305 that i was swapping in had a 2G and i didn't feel like changing manifolds and i'm kinda glad i did because i learned a lot about 2G's. After i rebuilt it, this quadrajet ran ok on a 350 So i'm thinking/hoping the carb isn't the issue here?
There is one drawback to the container test.
It should NOT be a factor in your case.
But there are two ratings for a fuel pump. Volume at idle, which you measured, and pressure. Normally volume is all you need to check. But I had a situation where the car cranked and ran fine.
Would cruise at 65 all day. But, if you punched it to pass someone, it would get you right alongside and shut off.
I checked the fuel pump volume, right to specs. Changed the filter, rebuilt the carb, nothing helped.
Finally borrowed a friend's fuel pressure gauge. I think that it was supposed to put out about 4 to 6 pounds or so. Barely put out 1/2 pound.
I replaced it, and ate the core charge because I wanted to know what was going on. The pump had two check valves, one output and one input. They were just units pressed into the body of the pump.
The input one had popped out and was rattling around in the pump slowly chewing a hole in the diaphragm.
Bet I have checked a dozen pumps for pressure over the years, every time they passed the idle flow test, they also passed the pressure test. But I checked anyway.....
It should NOT be a factor in your case.
But there are two ratings for a fuel pump. Volume at idle, which you measured, and pressure. Normally volume is all you need to check. But I had a situation where the car cranked and ran fine.
Would cruise at 65 all day. But, if you punched it to pass someone, it would get you right alongside and shut off.
I checked the fuel pump volume, right to specs. Changed the filter, rebuilt the carb, nothing helped.
Finally borrowed a friend's fuel pressure gauge. I think that it was supposed to put out about 4 to 6 pounds or so. Barely put out 1/2 pound.
I replaced it, and ate the core charge because I wanted to know what was going on. The pump had two check valves, one output and one input. They were just units pressed into the body of the pump.
The input one had popped out and was rattling around in the pump slowly chewing a hole in the diaphragm.
Bet I have checked a dozen pumps for pressure over the years, every time they passed the idle flow test, they also passed the pressure test. But I checked anyway.....
vandelay industries
1/2 ton status
i think at this point we need a list of all possible reasons in order of likelyhood and remedies for the current situation.
i am totally willing to buy tools/parts etc., and do anything necessary to get it running. but i don't want to take the carb apart etc. if something else more is likely.
i am totally willing to buy tools/parts etc., and do anything necessary to get it running. but i don't want to take the carb apart etc. if something else more is likely.
If you have a timing light I'd hook it up to the #1 plug and use a remote starter push button to crank it over, with the key in "run" and see where the timing marks are--its possible the distributor is off a tooth or two ,making it far enough out of time not to run for long..get any flames out of the carb,or backfiring when you crank it ?..
It could be one of 100 things causing it,or a combo of several..
I recall a friend having a similar issue with a 350 in a truck,and it turned out the base gasket on the carb burned up in one spot,creating a huge vacuum leak..after he replaced the module,cap & rotor,and a lot of other un-needed parts..
It could be one of 100 things causing it,or a combo of several..
I recall a friend having a similar issue with a 350 in a truck,and it turned out the base gasket on the carb burned up in one spot,creating a huge vacuum leak..after he replaced the module,cap & rotor,and a lot of other un-needed parts..
vandelay industries
1/2 ton status
i didn't do it with the timing light mainly because i can't hook the remote starter up properly---some of those 4.3's came with strut rod brackets sandwiched in-between the motor mounts---this is making it tight around the starter. i will have to remedy this later.
However, i did mark where post #! is on the distributor, took the cap off and manually turned the engine to about 12 BTDC and if anything the distributor position was too far advanced.
i am not getting flames out of the carb, but i did notice on at least one occasion of stalling that i was getting coughing and spitting thru the carb as it stalled.
It's too late to try starting it tonight. Will try again tomorrow and if that doesn't work, i'm prepared to put the carb that came with the engine back on. Although i really don't see how the jets or idle passages could have clogged up just sitting on the shelf?
vandelay industries
1/2 ton status
Will try starting it tonight with the new timing setting (don't think it will make a difference.....)
On a related note, if we look at a picture of the underside of a 6 cap, we see that the tangs are very long vs. a v-8.
http://members.toast.net/rbuchholz/hei5a.jpg
Why?
On a related note, if we look at a picture of the underside of a 6 cap, we see that the tangs are very long vs. a v-8.
http://members.toast.net/rbuchholz/hei5a.jpg
Why?
mrwilliamsburg33
1/2 ton status
You said it's been sitting on the shelf since '09 right? Or did I read that wrong? Murphy's law might suggest you need to clean that thing out real good...
vandelay industries
1/2 ton status
Yes, it's been sitting on the shelf since about jan 09. i don't see how it could have gotten clogged just siting there though?
That being said, i'm prepared to do (almost)whatever it takes to get it running.
Kain
3/4 ton status
carbs are funny that way, sometimes they will run like new others they run crapy
