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Topic: modern fuel in a classic VW  (Read 23323 times)

Offline cristie

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modern fuel in a classic VW

« on: April 01, 2015, 03:45:47 PM »
Does anyone have advice on fuel quality for a classic VW?  I've been running premium fuel through my 73 Beetle and the last time i filled up. ..at a truck stop. .I know better but was in a rush. ..my car began to putter. The filter is fine and no collapsed tubes. .Air cooled mowers need non ethanol. ..same with Beetles? Is there a limit to Octane consumed? ?
Thanks! !

Offline PapaKoch

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Re: modern fuel in a classic VW

« Reply #1 on: April 01, 2015, 05:45:36 PM »
Not sure about octane. I'm sure some else will chime in on that.
I have had better luck with 100% gas, usually 87 octane, here in Chattanooga. As I recall, 100% gas is recommended because it burns cooler than gas/ethanol mix. So the antique engine will run cooler and cleaner on 100% gas.

But, I must admit I usually fill up with gas/ethanol mix because fewer and fewer service stations have 100% gas. That said, Butters does not like it and does putter on the mix. If you are getting a lot of puttering, then it is a perfect time to go to Autozone and get something that says "Miracle" on it to clean up everything. I have had luck with adding some Marvel Mystery Oil to the gas every couple of fill ups. It also does not hurt to put some directly in the engine with the oil. Here is a link: www.marvelmysteryoil.com

Offline volksnick

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Re: modern fuel in a classic VW

« Reply #2 on: April 01, 2015, 06:39:55 PM »
100% gas is obviously best for ANY car, not just old VWs. The ethanol will attack and destroy all of the rubber fuel lines and carb seals. It is not good, especially if it sits. With that said, I've run it. I do run it. Its what's in my bug and bus right now, both of which haven't been driven much in the last few months. It doesn't seem to affect it, but I did have to clean out Bonnie's tank last year from sitting too long. My needle valve at the float also gets stuck sometimes at start up (maybe i should run some marvel through).

As for fuel grade, there is a lot of discussion on the octane. Apparently, the german scale that is often printed on the inside of the gas door (91) is supposedly different than what is currently available. Most people with stockish engines will report 'pinging' sounds when running higher octanes than 87. Remember, these cars were initially designed in the late 30s.

I'd run 87 and preferably non-ethanol if you can, but wouldn't sweat it unless you were going to let it sit for a while. Your results may very.

Just don't ask what oil to use…. that will start another world war!

Offline cristie

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Re: modern fuel in a classic VW

« Reply #3 on: April 01, 2015, 10:05:25 PM »
Thanks for the info!  I will read up on "Miracle". Thankfully,  there is a station near my house that sells non ethanol fuel  8)  I don't want to start  a war, however I am interested on why there is such a debate on oil.  I need to pick some up. ... anything I  should avoid?

Offline volksnick

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Re: modern fuel in a classic VW

« Reply #4 on: April 01, 2015, 11:41:16 PM »
Miracle is a "Tom and Ray" reference. They always say to get something from the store that promises a miracle.

As for oil, you'll have those that swear by synthetics. You'll have those that swear by dinosaur oil. Then there is the whole debate about oil viscosities and any additives, etc. everyone develops their routine that works for them and they swear by it. I just try to keep a little over two quarts in mine!

Offline cristie

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Re: modern fuel in a classic VW

« Reply #5 on: April 02, 2015, 06:21:52 AM »
Good stuff. ..Thank you for the info.  Car mechanics is 100% new to me.  There's probably going to be a lot of newbie questions from me.

Offline volksnick

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Re: modern fuel in a classic VW

« Reply #6 on: April 02, 2015, 09:20:05 AM »
To be honest, I've learned what I know from playing with VWs. I read the Idiots Guide from cover to cover and he really explains things in a way that makes you get it. He talks about detergent oil and non-detergent oil, which I'm not sure you can even still get!?!? But it he explains all of the little things that matter. From there, I was able to understand more complex conversations. It's an excellent first step.

Offline Got Bug ?

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Re: modern fuel in a classic VW

« Reply #7 on: April 02, 2015, 05:42:46 PM »
I have been using the gas/ethanol blend for the last three years in my daily driver, a 1963 bug with stock 40 horse. It seems okay and will run to redline without incident.

Offline cristie

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Re: modern fuel in a classic VW

« Reply #8 on: April 03, 2015, 02:21:24 AM »
I ordered the Idiot's Guide Tuesday. Glad to hear is goes in such great detail!

Offline Zen

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Re: modern fuel in a classic VW

« Reply #9 on: April 03, 2015, 05:57:50 PM »
I'll throw my 2 cents in, which ain't worth a nickle, but . . .

If you don't let it sit, gas with 10% or less ethanol won't do any immediate damage . . . it may cause rubber and plastic parts in the fuel system to degrade a little faster than normal . . . or maybe not.  It will start going bad if it sits for a month or two . . . after about a year, you'll have to pour lighter fluid on it to get it to burn.  It stinks and it's sticky.  I always ran the cheapest gas I could find . . . or whatever was closest to walk to when I ran out (when you don't have an odometer, a gas gauge or a good sense of how many miles you've gone, that tends to happen a lot!)  If it's stock, stick with 87 octane.

On oil, it really doesn't matter that much.  I used to run HD-30 until the Godfather (look at the thread about David Johnston to learn more about him) convinced me that it was OK to run multi-viscosity.  After that Castrol 20-50 was my lube of choice.  The main thing is CHANGE IT often.  An air-cooled VW engine does not have an oil filter.  It's got a screen on the pickup tube that will keep rocks from being pulled into the oil pump, but nothing to actually filter it.  Change it every 2000 miles.  When you do, check your point gap.  If you need to adjust it, reset your ignition timing afterwards.  Never exceed 32 degrees of advance on the timing at full advance.  Also, adjust your valves while you are doing all this.  It's a good idea to adjust your brakes at the same interval.  I know if you are new to mechanicing, it sounds complicated and labor intensive.  Compared to a modern care, yeah, it's labor intensive . . . but it's not really that hard and well within the capabilities of most people to do-it-yourself . . . as long as you don't mind getting your hands dirty a for a couple of hours every two or three months.

Offline cristie

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Re: modern fuel in a classic VW

« Reply #10 on: April 04, 2015, 01:27:37 PM »
I'll pay ya a nickel for that bit of advice, Zen! Sounds complicated,  but fun all in the same. I believe Vincent is ready for a little TCL. The filter is getting full.  I'm also youtubing changing oil.  Like i said. .I'm brand new !!!

Offline Russ

Re: modern fuel in a classic VW

« Reply #11 on: April 04, 2015, 04:46:36 PM »
I've always run 87 octane in my bus. There is no harm in running higher octane fuel, but there is no benefit either. An exception may be though some brands mix detergents in their premium fuel that may be good once and a while.

I used to try and find 100% gas for the bus and the Audi, but it's getting harder and harder to find. I gave up, I run the ethanol blend in both and don't really see any difference. Plus I am skeptical of stations that charge more for "ethanol free gas", there is really no way to tell if it's truly 100%.

Offline volksnick

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Re: modern fuel in a classic VW

« Reply #12 on: April 04, 2015, 09:22:09 PM »
The oil change is relatively easy! Your sump plate (round disc with 6 nuts holding it on) should have a drain in. Drain the oil and then remove the sump plate. Clean the plate and the screen that comes out with it. Then reinstall with the paper gaskets. Put the drain plug back in and pour in fresh oil. The big thing is not to over torque everything. They torque settings are really light on those nuts.

Offline volksnick

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Re: modern fuel in a classic VW

« Reply #13 on: April 05, 2015, 01:35:15 PM »
So I just saw the picture you posted! There are many fields of thought on the fuel filter and most everyone agrees that the fuel filter should not be in the engine compartment. The way it is on your bug (between the pump and the carburetor) puts stress on the fuel inlet nipple on the carb with the added weight of the filter plus the fuel. The brass nipple can and will pull out of the carb over time and then the engine runs (and the pump pumps the fuel everywhere) until the carb bowl runs dry. This is how the fires start!

The other option is before the pump, but the plastic fuel filter can end up resting on the intake and the preheat riser. The plastic can melt and the same issues can occur!

The generally agreed upon location for a fuel filter is under the fuel tank in the front or beside the transmission in the rear.

Where ever you put it, carry a fire extinguisher.

I tried looking at Bob Hoover's Fire article, but the link seemed down.

Offline cristie

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Re: modern fuel in a classic VW

« Reply #14 on: April 05, 2015, 05:03:32 PM »
I tried looking at that link,  too. Gah I can't wait for that manual to come in the mail! ! I really appreciate all the responses. Truly :) this web site rocks

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