power loss, burning, lack of fuel...wtf??

Yeah man, weird huh!!?? Apparently the flooding was high enough in the carb that it went into the line to the canister! When I talked to Holley tech he said that was probably what happened. The tang he's referring to is the part that maintains the floats level....don't think I'm wording that correctly.... But I wish I was mixing it with vodka instead of dealing with carb issues!!!
 
Ok , we May have a conclusion!!
Took the carb apart again and when upside down the float should be at 90* (I'm sure most of you know that). Mine wasn't, so the needle and seat weren't able to adjust correctly. The "tang" is the part that sticks out from the main body of the float and had to be bent accordingly. After that it sat level and she responded to the adjustments. This seemed to have been causing some flooding as well as running Rich. We also found that the gasket to the metering block was on backwards. The gasket is 90% symmetrical except for one tiny hole that is what allows the vacuum for the advance! She purrs at 650rpm, and feels great. No more white smoke on starting and no hiccups whatsoever after she's warm. Hopefully my mileage is up too!!
A million thanx for all the feedback and suggestions!!!
 
Great diagnostic work! The symptoms were so confusing that it had to be multiply issues, but which ones?
 
Well gentlemen, the saga continues.... After all this I was stoked to see what my mileage May be up to...insulated fuel lines, new plugs, rebuilt carb, vacuum advance working....and after all that...7.5 mpg :frown5: I know, mpg and IH don't go together but this is ridiculous. I even brought it to the tire shop the other day and my alignment and tow was way off, so thought that May be it.....nope!! Still 7.5!! I've scoured the internet and keep hearing anywhere from 11-15 mpg...I keep rpm down for the most part, don't gun it, premium gas, and under 70 mph on the rare occasion I can even get close to that. When I got her I was hovering around 10 mpg and all the work has somehow dropped it....any ideas!!?? Timing is 10* btdc, idles dead steady at 600...doesn't seem Rich....gggrrr!! Does seem to be much worse with the trailer but I keep hearing that with the gearing and design of the truck it shouldn't be much different... And those people are getting around 11 with a t-all....I'm drowning in gas bills!!!
 
Just a thought, are you using your speedometers odometer to measure mileage? A change in tire size or, gearing will affect what you odometer is reading. Try using a gps to check the accuracy of your speedometer. If you don't have a gps, most smart phones have apps you can download that are pretty accurate.
 
That is pretty lousy mpg if accurate. I'm with hondo in wondering if you're not actually traveling more miles per tank than what your indicator is showing. But I guess if you're feeling a bigger pinch in your wallet than before, there must be something to it. It doesn't sound like your driving habits are to blame. That leaves a fuel leak, fuel being siphoned/stolen, poor state of engine tune, or carb issues as the potential culprits. The last one being the most likely of the bunch in my mind.
 
Don't know how hard it would be to change the jets back on that particular carb, but since you increased jet size, and then found a bunch of other problems that were fixed, you might want to go back to the smaller jets and see if that helps with your mpg.
 
Agreed about putting the old jets back. Also check the gasket on the power valve, I've seen these leak and make thing run Rich. To tune the Holley on my Scout I welded an o2 sensor into the exhaust. You can get fancy ones with readouts or just get one and test like this: https://www.youtube.com/watch?v=wejuxr11cgu

My Scout will occasionally get 15 mpg on a tank and averages 12.5 mpg. A vacuum gauge will help in the process too. You'll need to know what vacuum level the power valve opens.
 
hondo said:
just a thought, are you using your speedometers odometer to measure mileage? A change in tire size or, gearing will affect what you odometer is reading. Try using a gps to check the accuracy of your speedometer. If you don't have a gps, most smart phones have apps you can download that are pretty accurate.
Click to expand...

Yes: check your speedo/odo accuracy with a gps, because you can never be certain any pos or their 'mechanics' didn't make any changes to speedo gears or drivetrain.
 
How much weight are you towing? The 11-15 mpg numbers that are thrown around are probably for just the vehicle with no trailer or drag. You also indicate pulling up and down hills so that won't help you either.

What do you get running around unloaded and not towing?
 
On a trip to mammoth, total elevation change 9000 ft, in my 68 1200 travelette, 100% origy, 304, t34, 4.89 gears with 2000 pounds of granite in the bed driving 70 mph, I got almost 14 mpg round trip. 700 + miles. I never spared the whip up hills. Just mated it.

It surprised me to get that mileage.
 
The issue with the tires is minimal to me due to the fact that they are very close to the exact size. They are a/t from roadies though. I needed/ wanted to keep the same size due to mileage as well as not having to change the drop of the hitch. Also, my runs are the same so usually I know the mileage of the routes.
I talked to Holley again and this guy is thinking its the fuel pump on the hill issue. Did an 80 mile tow yesterday and got a whopping 7.9 mpg lol. Once again on some hills she make the trailer her bi*ch, and others the slave became the master...
I know 11-15 seems like it could be high and I'm not looking to get 15 mpg but >8....not acceptable lol
 
blasttruck said:
the issue with the tires is minimal to me due to the fact that they are very close to the exact size. They are a/t from roadies though. I needed/ wanted to keep the same size due to mileage as well as not having to change the drop of the hitch. Also, my runs are the same so usually I know the mileage of the routes.
I talked to Holley again and this guy is thinking its the fuel pump on the hill issue. Did an 80 mile tow yesterday and got a whopping 7.9 mpg lol. Once again on some hills she make the trailer her bi*ch, and others the slave became the master...
I know 11-15 seems like it could be high and I'm not looking to get 15 mpg but >8....not acceptable lol
Click to expand...

With my 304-powered Scout II, I get about 9-10 mpg towing my 3000+ lb sailboat/trailer combo that sits quite high. Normal 60 mph freeway mileage is around 14-15 mpg at around 2400 rpm.

80 miles is not really long enough to get a low-error mpg calculation with the typical 'miles driven/gallons to refill' method. In my experience, a few hundred miles provides a more accurate figure.

And I'm going to trust you on your 'miles driven' figure...
 
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Hey erik,
that's a good point...this is a 14x8x8 trailer with no nose lol so its like towing a wall. I spoke with Holley again today and I'm thinking of just getting a new carb and then either celebrating my new found milage or learning to embrace my daily gas station visits. I think the issue of the fuel pump has been laid to rest since it works fine normally and has for 9 months. Also Holley agrees that mechanicals usually are either good or bad.....
Still open to suggestions if anyone has any!!!
Thanx!!
 
Just saw you replied as well scoutboy.... I'm putting in between 10-15 gallons each fill up....sadly 80 miles is equating to 12 gallons so I can't do much more without the use of a tow truck lol
 
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