Longest trip yet...MPG suck!

[ETAModel]

Originally Posted by 700rpm

As a new owner of a Model A you should get a copy of the original owner’s manual. It explains everything you need to know for proper setup and driving. They’re available from all A suppliers.

So far I have Les Andrew's book on the model A, the first of the set. I'll get more soon. I'm surprised his book doesn't show info on type of plugs, ie heat range, gap for plugs, info on condensers, limited info on points, etc. Maybe I'm expecting too much. Guys at the club said its all I need.

[ETAModel]

Originally Posted by ronn

I agree- 10 mpg does suck, but It sounds like it will be tough to get much more then 15 mpg out of your car.
so many variables and the biggest being the weight , as mentioned and the other question is, what condition is your engine in?


is it tired?

I would not call the motor Tired at all...I have had it up to 62 MPH, just to see where it would top out at. I usually drive around 45. I haven't checked compression, but I see no need, it isn't smoking or fouling plugs. I'm new to model A's, but worked around and on motors most my life.

[ETAModel]

Originally Posted by nkaminar

GAV: Gas Adjustment Valve.

Several things effect gas millage. The GAV should be turned in while cruising down the highway. The spark should be adjusted correctly and when cruising down the highway advanced a little. Make sure the points are adjusted correctly and the car is timed correctly. Also, just like in a modern car, how you drive can effect mileage. Keep the tires inflated to 35 psi. Overdrive helps and the gear ratio of the rearend will effect mileage. Years ago I changed out 4.11 gearing for 3.7 gearing to improve my coupe top end and mileage.

I quickly figured out the tires were low, so I got them to 35psi, certainly handles better, stops quicker.

There's about half a dozen guys in the A club who gather for coffee and politics every Saturday morning; they heard and test drove the Fordor, said the timing sounded right. I know its and easy fix, but had more pressing issues at first, like getting her to start.

My uncle had a 31 A, he hauled Nitro Glycerin for a living in it, and sent it to Dallas for an overdrive, new shocks and overhauled the brakes. I cant see spending the money on an overdrive to improve MPG, I'm not driving it to Houston twice a week like he was.

[ETAModel]

Originally Posted by 1crosscut

Something that will probably help with you gas mileage is to stop using premium high octane fuel.
High octane fuel is designed to be harder to ignite. This is to reduce the tenancy for fuel to prematurely ignite in high compression engines. Model A's even with the higher compression heads are still a low compression engine. Put the lowest octane fuel you can into your car. It will give you more power and most likely better mileage.

In regards to the GAV as I understand it, it is not a good idea to close it all the way as it can cause the engine to run too lean and possibly cause engine damage.

I thought you needed to run Non-Ethanol gas in the model A, at least that's what I heard around here. I know there's a huge issue of "E" Vs "Non E" gas on the tractor forum (I have a 56 Farmall). Around here the only straight Gasoline is high octane, I guess for sportscar purists.

I'm also certain I can run E-10 gas in the Fordor and have few problems, unless it sits in the tank too long and turns to sludge.

[ETAModel]

Originally Posted by Bob Bidonde

I have a 45B Deluxe Coupe and a 190A Victoria Coupe. Both have Model "B" engines with Model "A" Zenith carburetors, and no overdrive. Both have stock 3.78:1 differentials. The 45B has a 4.6:1 Compression Model "B" head, and the 190A has a 5.5:1 Model "A" type head.
The 45B Coupe gets 15 mpg and the 190A gets 18 mpg. I run both cars with the lowest cost 87 Octane with Ethanol gasoline I can find in Gulag New York.

So i take it you recommend running ethanol gas in the A? I know we ran anything that would burn in our JD model A tractor, it was called an All Fuel Model and ran best on Drip, unrefined low octane gas..

[ETAModel]

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Originally Posted by ryanheacox

I tend to get mid to high teens in my Fordor with 3.78 gears and I live in hilly terrain and have a lead foot. Sounds like the carb is in need of some attention, GAV needing to be 2/3 of a turn out is suspect. Dragging brakes are a good suggestion too.

The GAV doesn't NEED to be out 2/3 a turn to run properly on this A. That's what was recommended by a local expert. Yesterday I turned it almost off, still experimenting, and think I had it shut off too much as it bogged down in town.
Today I had it opened just a smidge ( the technical term ) more and it ran fine.
I didn't see a reference to setting the GAV in Andrews book...please help me here.

[ETAModel]

Timing is very important. You want the spark to be able to reach the full measure of advancement as recommended by Ford Motor Co's publications but an operator of one of these cars has to know when to retard the spark not only for starting but also for pulling a load up a hill. Nothing is automatic on these old cars so it all has to be done by the operator to get best mileage.

This is new info for me...Are you saying climbing a hill or steep grade I should RETARD the spark ??? That might explain many things, like poor power on up grades, water overheating in radiator...

Guys please chime in on this!!

[ETAModel]

Originally Posted by rotorwrench

The GAV is the trim adjustment control for the high speed jet circuit in the carburetor. Adjust during cruise for best overall running down the road. The only other adjustments to it would be for higher or lower altitudes or temperatures. The idle circuit takes care of idling and it should be adjusted for best running at idle or best manifold vacuum if you have a MAP gauge.

Timing is very important. You want the spark to be able to reach the full measure of advancement as recommended by Ford Motor Co's publications but an operator of one of these cars has to know when to retard the spark not only for starting but also for pulling a load up a hill. Nothing is automatic on these old cars so it all has to be done by the operator to get best mileage.

The type of terrain can also make a difference. A car will get the best mileage in relatively flat land situations and at relatively slow speeds compared to modern highway speeds. How the milage is measured can also have an effect. The old speedometers need to be accurate or a GPS should be used unless it is a closed course of know distance values.

The speedometer doesn't work, as I said in the OP, I was using the Speedbot app to measure speed and mileage.

[ETAModel]

Originally Posted by 1931 flamingo

When I had my A I never was concerned with gas mileage. Having too much fun. ,When it got to a 1/4 tank I just put more in. My 40 coupe now with dual 97's and hi-comp heads is a gas guzzler (like my 300 C with the HEMI. Still having too much fun.


Paul in CT

Thanks for READING the OP...as I SAID, I am not concerned with the mileage from a money aspect. The gas gauge doesn't work and I really don't wanna run out of gas. There may only be 5543 square miles in your state, but there's One local Ranch here that's bigger than that. The whole state covers 268,597 square miles. Its not uncommon to drive hours without seeing a gas station.

So if the tank holds 11 gallons, (but 10.2 is all I can get in it), and I hear to run it past 1/4 tank is flirting with stalling (due to low gas pressure to the carb), then 70 miles is the max I can safely drive before looking for gas. Thats the distance to my favorite fish house and back.

If she got say 18 mpg then I could safely drive 125 miles, quite an improvement.


BTW, how big is the tank on your 300C ??

[Bill G]

I usually get 17-18 around town and 20 out on the open roads, which are mostly country roads and not actual freeways. Once in a while I will get a surprise and the last tank was 22. Stock tranny and rear end, with no overdrive. I think putting the HC head on added an average of at least 1 mpg, but that is not based on any scientific data. I cannot tell any mileage gain or loss based on which kind of gas I use. I generally put non-ethanol in it for the winter when sitting, but this time of year I don't bother. Particularly since when we are out on tours some towns don't carry it at all. Early on in my Model A ownership of about 4 years now, I was getting around 13-15, but I played around with the timing, spark plugs and driving habits that all taken together has turned up some decent mileage numbers. Oh, and by the way, if your speedometer/odometer is reading a lot too slow, the resulting mpg stats will suffer too. <edit> I see now you are using an app for the miles, disregard the speedometer issue. <edit>

[Ed in Maine]

This whole topic is why they engineered carbs to do away with adjustments. We get distracted waving to people and blowing our horns and just enjoying the drive. This is the Model A experience where you should be paying attention and occasionally making carb adjustments to suit the driving conditions. Eventually, we get used to doing things correctly with our Model As and it does drive more efficiently. In the mean time, just have fun and fill it up before you start a tour. Ed

[rotorwrench]

Changing from E10 to regular no E fuel may require a GAV adjustment. If you run alcohol, the milage will decrease. A person could likely run E85 but it would get even worse milage. A lot of the Buckeys stations sell regular no E fuel.

[700rpm]

I get about 14 mpg no matter what kind of gas I use. All stock, Zenith carb. I haven’t noticed any diff between E and non-E except the price, which is significant in Oregon.

[ETAModel]

This A has a Tillotson carb. Not sure if there's any large difference.

[Karl]

The exact position of the GAV for optimal running varies from car to car
Each of the 4 Model A's I have owned is slightly different but somewhere around a quarter of a turn open is about right. Once set I don't touch it (literally for years ) other than to pull it out to choke for starting . If its running ok at speed but not at stop then I suspect its a carburettor issue rather than the GAV -I have no experience with Tillotsons but they apparrently work well if set up properly but the original Zenith works well for me and is very simple

[shew01]

Originally Posted by 700rpm

As a new owner of a Model A you should get a copy of the original owner’s manual. It explains everything you need to know for proper setup and driving. They’re available from all A suppliers.

Here is an online pdf file.

http://www.palmbeachas.com/Model-A-I...ion-Manual.pdf


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[shew01]

Originally Posted by ETAModel

Thanks for READING the OP...as I SAID, I am not concerned with the mileage from a money aspect. The gas gauge doesn't work and I really don't wanna run out of gas. There may only be 5543 square miles in your state, but there's One local Ranch here that's bigger than that. The whole state covers 268,597 square miles. Its not uncommon to drive hours without seeing a gas station.

So if the tank holds 11 gallons, (but 10.2 is all I can get in it), and I hear to run it past 1/4 tank is flirting with stalling (due to low gas pressure to the carb), then 70 miles is the max I can safely drive before looking for gas. Thats the distance to my favorite fish house and back.

If she got say 18 mpg then I could safely drive 125 miles, quite an improvement.


BTW, how big is the tank on your 300C ??

This running board setup may be an option.

https://images.app.goo.gl/RCUUJNP78QNGGygx6


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[nkaminar]

ET,

Fix your gas gauge. It probably just needs a new float. Easy to do and you don't have to drain all the gasoline out of the tank to fix it.

Fix your speedometer. Test it with an electric drill with an adapter to insert into the device. You may just need a new speedometer cable. You may have to run the drill motor in reverse.

The spark has to be adjusted depending on the circumstances. It is a mater of testing the adjusting lever position. There is a position where retarding the spark will slow down the motor but advancing it will not make a change. This is the knee in the advance curve. You need to experiment to find the knee for different conditions.

Keep a log. I have a small note book that I keep in the car and record odometer reading and the amount of gasoline I buy each time. I also record things like oil changes or any other things of note.

Pumping up the tires to 35 psi will help your mileage. You may try another drive. Park the car on a flat place and try pushing the car. It should push fairly easy. If you cannot push it look for the cause.

[Rob Doe]

Good comments above.

I may be confused, but my GAV controls fuel to the Cap jet, which is the mid range jet, above idle up to about 35 mph. Or so I thought.

The Zenith carburetor hinges its float perpendicular to the center line of the car, and therefore when applying the brakes to stop, the float will dip and rise as gas sloshes in the float bowl. On my car, I sometimes run the GAV at 3/8 turn open rather than 1/4 turn to alleviate this. I run at 1/4 when at higher speeds.

I'd like to add a bit different description for using the spark control.

Count your notches/bumps on the control from top to bottom. There are 10 or 11. Each mark is 3.6-4 degrees of crankshaft timing advance, 40 degrees total. The lever on the distributor moves only 20 degrees properly adjusted because the distributor turns at 1/2 engine speed. A 4 cylinder engine fires a cylinder every 180 degrees of crank rotation, all 4 cylinders in 720 degrees or 360 x 2 complete revolutions.

The Ford information times the Model A engine at Top Dead Center on the compression stroke of cylinder #1. You place the spark control all the way up before setting this timing. This will be the maximum retard position.

You always start the car in this retarded position. This protects the starter and the teeth on the starter ring from kick back and possibly damaging one, the other or both. It also protects a rookie that misuses the hand crank from breaking his thumb, wrist or arm. It makes it easier for the starter and the battery as they don't have to overpower the compression of a rising piston.

After the engine starts I immediately advance the spark control 2 or 3 bumps. And from then on, when driving I use a formula given by an old salt that was an old salt older than myself. Eh, a long time ago, too. For each 5 mph driving speed, lower/advance the spark control 1 bump. 30 mph = 6, 40 = 8, etc.

It is my understanding that the Model A engine cannot make use of more than 32 degrees of timing advance, but that is beyond my knowledge level as to why. I might try a full 10 or 11 bumps if I was going 55 or 60 after say, robbing a bank ... and then only if coppers were hot on my tail and shooting.

In central Illinois it is pretty flat with only occasional hills. If climbing a fair grade in high gear at a low speed, I retard the timing a couple bumps to prevent spark knock as someone else stated in a previous reply.

Some folks time their engine with the spark lever advanced 1 or 2 bumps. When placed in the full up position then, the engine fires 4 to 8 degrees after TDC. This adds further protection for someone using a hand crank, and I think makes a very slow idle possible. I have not tried this myself to see about the idle. Someone else might comment on that.

[ETAModel]

Originally Posted by shew01

Here is an online pdf file.

http://www.palmbeachas.com/Model-A-I...ion-Manual.pdf


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Thats great info, thanks a lot, its now on my desktop.