Ethanol Gas cause issues?

[SCHRUMGMC]

Because I've put Regular no Prem in my '59 and it came to my attention that it could be the gas messing things up and making it seem like it wants to die??? Its a maybe...Anyone have the same issue?

When I press the gas it wants to die, and i've read on here where it can cause issues with the Carb etc

[OrrieG]

I have ran 10% ethenol in my 64 Chevelle as a DD for years with no carb problems. I know from personal experience its hard on small engines like lawnmowers and generators, I use an additive in those. If it is dying when you try to accelerate probably accelerator pump or timing, both previously discussed in other threads. Higher octane will not make it run better, these were designed to run on gas with a much lower octane that was common in the 50's.

[SCHRUMGMC]

Well the reason I say, is because of all my friends and their '71 Chevy and '77 GMC they run Premium..Thanks again Orrie

If its the Accelerator Pump, how can I replace it?? I know take the Carb apart but where is it located? I did notice when I had my Little cousin pressed the Gas pedal, and I saw the spout and didn't see and gas squirt out of it so it could be the Accelerator Pump. Because I have to baby it when it wants to stall and when I do it can run good and I also have to pull the choke out just a little bit and I'll see what I can do, I have been looking at a 1959 Gmc manual online and I've been reading on that area...Its two things either the accelerator pump or the vacuum advance...I guess it'd be good to replace both so I won't have to replace either soon

[OrrieG]

The carb kit will come with a diagram and sometimes instructions. From memory you basically need to disconnect enough of the external linkages to get the top part of the carb off. Stuff a rag in the hole to keep screws from falling into the manifold. When it comes off the float will be dangling as will the accelerator pump, it looks like a inverted cup with a spring around a shaft. Replace the pump part. While you have it apart clean out any crud in the bowl and check the float level, that is usually in the diagram that comes with the kit to. Put a little gas in the float bowl. Put it back together, do not over tighten the top screws. If you then hit the accelerator and you get a squirt your carb is fixed for now. Save the rest of the kit in case you need to do a complete rebuild later. Like always take pics and notes as you disassemble.

[SCHRUMGMC]

It dawned on me, it could be the fuel filter and the fuel filter looks so old and when you blow some air its clogged.I bought an inline fuel filter from Wally world... Can I put it where the fuel line goes into the carb?

[lha1992]

Sounds like maybe your timing is off alotttt!!! I'd check your timing an if you have points check your dwell also. If not an you got HEI just time it. Replace your old fuel filter with the new one an give her a go. If the fuel filter an timing check doesn't help I'd just take the carb off an rebuild it if your gonna go through all the trouble to replacing the accelerator pump.

[SCHRUMGMC]

I'm going to get the Vacuum Advance anyway and keep it on the shelf when I need it..When I get the money I'll buy the rebuild kit for my Carb...Putting the inline fuel filter in soon...Can I leave the other one on there but take the actual filter out ?? I think I can

[Custom 68]

Around here not all premium fuels are alcohol free. I would not just go by the fact it is premium. You will need to check if you are wanting to run ethanol free. Like OrrieG said I try to run the ethanol free in my small engines.

[Wheelie]

Sounds like your not getting a pump shot or no fuel to the carb like you mentioned. Also some plungers are made of leather. If yours is you can renew it in some ATF. You know your getting pump shot by taking the air cleaner off and look in there when giving it gas. If no fuel squirts problem is either no fuel getting to bowls, or carb probs. just FYI though, I had hell last year during the summer time here in Texas because of ethanol fuels, especially the fuelie vetoes. Ethanol has a lower boiling point and tends to evaporate/ vapor lock easily. Alcohols boiling point is like 175 deg. or something crazy like that. Most upper intakes radiate that much heat alone. Adding ethanol treatments like the lucas stuff and a few others really helps and so does adding a phenolic spacer. They now sell ethanol safe carb rebuild kits for most carbs as well if you have to rebuild your carb. Also you need to know that ethanol is corrosive as well. We have been doing all stainless fuel lines or ethanol resistant hose on all new builds or system services that require fuel line removal as a precaution. Even more now because rumor is the government wants to mandate a higher percentage ethanol into our fuels. Something like 20% min.

[mr48chev]

It's pretty well documented that gas with ethanol is hard on older fuel system parts. Mostly affecting the rubber (or rubber type) parts like the plunger seal on the accelerator pump. That could be the case or it could just be that the accelerator pump is worn out along with other carb parts being tired and the carb needs a rebuild. There are online instructions for rebuilding almost every carb in existence if you take the time to hunt them down both written and videos on Youtube.

One important thing when taking a carb apart and putting it back together is be gentle with it. there are some parts in some of them that are easy to damage if you try to force things or get heavy handed with them. Study the carb to see how it should be take apart without forcing anything.

Yes you can put the fuel filter in the line that goes to the carb. I also like to have a filter between the tank and the fuel pump to keep crud from fouling the fuel pump.

You can check the vacuum advance by pulling the hose off it and putting a length of hose on it and either sucking on the hose to see if you get a resistance and can see the advance work or using a hand vacuum pump to check it. I've popped the hose off at the carb on a lot of engines and sucked on it to do a quick check of the advance diaphragm. If you just suck air and don't get a resistance the diaphragm is bad.

Post the exact brand and model of carb you have on the engine and maybe someone can dig up instructions on rebuilding it.

[mr48chev]

NOTE! I would not take that carb apart until I had found the correct kit to rebuild it or at least the accelerator pump.
I've tried three sources and cannot find a carb kit for a 1959 GMC with a 270 six cylinder in it.

We may have a winner as this link shows a kit that may be the right one. http://www.classicpartsusa.com/categ...rburetor_Items

[SCHRUMGMC]

I bought a new Vacuum Advance today at NAPA Auto Parts..Hopefully this fixes the issue !!!

[Rednek13x]

If you cant find a pump that has premium NON-Oxy fuel, regular 87 is your next best as it has a higher Motor Octane Number than Premium with 10% ethonal.

[SCHRUMGMC]

Oh okay thanks

[SCHRUMGMC]

my new vacuum advance doesn't have the thread like the old one does? What hose can I use to put over the old thread side of the line and on the VA?


Looks just like this (NEW ONE)

[OrrieG]

You will need to get a barb fitting the same size as the VA nipple. Disconnect the tube from the carb and take it with you to make sure you get the correct type of fitting (flare vs pipe), will probably take a male coupling too.

[SCHRUMGMC]

Oh okay, so I don't have to take it back? I'll see what I can do

[SCHRUMGMC]

Will I have to take the old VA off? I can't do that by myself, Why would it take more than one? I need the Female side of it...Take actual line off? does it go below the Fuel line? Fuel and emissions ?

[OrrieG]

Is this what your looks like? You need to get a barb fitting that goes on the male line fitting. If the end of the fitting is angled it is a flare fitting, if not pipe, probably 1/8" but that is why I recommended taking the line with you. Then a short piece of vacuum line and you are set.

[SCHRUMGMC]

but the line is so long can you show me the full line Orrie? I think I know but i am not sure...does it go below the fuel line like i said before??... So a 1/8 Barb fitting ?

[SCHRUMGMC]

Orrie so can I use that Vacuum Advance or not? the original looks completely different from it???? I'm so confused

I found out the original isn't made anymore and i'd have to buy it through brothers but i cant

[Katrina/10]

The vacuum advance in the picture you posted is the wrong one.

[SCHRUMGMC]

Damnit..Where can I get the Original one???

[coralhead]

LMC has them but they are about $45 + shipping.

[SCHRUMGMC]

http://www.americanclassic.com/Googl...M47-2-1959.htm


Thinking of getting this one