PD-4107 Fuel Gauge

[glerler]

Working on a PD-4107 that has the optional fuel gauge.  I can't  find information for the sender that GM used.  I am assuming that it is an ohm based.  Also that since it has 2 leads the black is for grounding the sender.   I am getting around 180ohm from the lead now and the tank is aprox full.  I have the full service manual for the bus but it gives no insight other than being optional.    If I have to replace the sender are there an suggesions?  thanks

[RJ]

NAME?? -

For all your GM coach needs, simply pick up the phone and call Luke @ US Coach in NJ. 1-888-262-2434 is his toll-free number from anywhere in the USA.  Competitive prices, ships same day when you pay with plastic money. Strong supporter of our crazy hobby, support those who support us!

FWIW & HTH. . .

 

[daddyoften]

Is the optional sending unit something that can added to one that doesn't have one? Mine doesn't have one. It's a 4107 also. Thanks,
Eric

Sent from my XT1254 using Tapatalk

[chessie4905]

Yes, there are holes on the top of the tank with a round plate covering the location. You probably need to pull tank to access it. You'll also need to remove filler tube assembly. There is a plate in floor inside right wall above filler. You can disconnect fuel line there also. Filler assy has 8 small bolts securing it to tank. You remove the bolts that hold the tank cradles to the body from below(about 10 or 12). Do NOT remove or loosen straps bolts. Then slide out on left side. It will ride on body channels. Oh yeah, drain out any fuel in tank first. There is about a 3/4" drain plug inside on right bottom end of tank. Now is a good time to clean tank inside and out; inspect and treat any rusted spots on outside. It is pretty heavily tin plated inside and out so should look pretty good unless it has set for years with little fuel in it. I cleaned out the bottom inside of mine with pea sized limestone and a gallon of lacquer thinner. I just tilted tank up and down end wise to allow solution to slosh back and forth. Worked really well.Drain and rinse with some diesel fuel or kerosene. When I filled my tank, I watched fuel gage and made note how many gallons it took to cover fuel pickup, gage starting to move, 1/4 , 1/2, 3/4,and full. Keep it for reference. There is a gm part number for the gage, which is indexed to proper direction in tank. SOME tanks already have the sending unit in tank, just not wired or no dash gage installed. Get a strong flashlight and look through fuel filler hole at night. You may be able to check. Luke may have sending unit or know where to get one.Standard and optional tanks use same sending unit, as tanks only differ in length.

[lostagain]

As nice a modern convenience as is a fuel gauge, you can do without, by keeping a log and fueling at 500 miles or 800 miles, whatever makes you comfortable. A lot of buses we drove in the '70s and '80s didn't have gauges. We kept a form M27 in the pocket on the vertical part of the dash.(We at Brewster's were a Greyhound subsidiary, and I think the M27 form came from Greyhound). That was to track the mileage and fuel put in. We used the hubodometer as there was no odometer on the dash either. That was what we were trained to do, and  you get used to it. If my bus didn't have a fuel gauge, I don't think I would bother putting one in.

JC

[buswarrior]

The old adage:

"Only those with fuel gauges run out of fuel..."

Too few fuel gauges tell the truth, there's always a fudge factor needed, depending on its own quirks.

Safe mileage stickers used to say 500 miles on them, in highway service. Shorten that up, if you are tooling around in an urban environment.

And does the busnut know how few inches of fuel is sloshing around when one is down to what one thinks is a "healthy" 40 gallons left?

measure the bottom of the tank in inches. (length x width x depth of fuel) divided by 231, equals US gallons.

Gauge, or no gauge, I've driven bothways, install one if you like, but you don't need to.

happy coaching!
buswarrior

[Cary and Don]

Our 4107 had a fuel gauge. A rope with a bolt. LOL Very acurate. Tied a knot at full. We find it hard to trust the one in the Eagle. It varies too much on which way it is tilting.

Don and Cary

[LuckyChow]

We didn't have fuel guages in buses till the 1980 model 10's came out at Trailways.  Just kept up with the mileage on the tank and fueled at 500 usually.  Having said that, I do enjoy having a guage on the dash.

[glerler]

What I am after is what are the spec for the fuel sending unit so that I can   A- Check the sender and B-get a guage that will work with the current sender.  A new sender would be a hastle as it looks like i would have to remove the tank!
Thanks for the replies

[LuckyChow]

As previously stated, call Luke.  He will know the answer to your questions.

[glerler]

My bad.  Thought he was just a parts source referral.  Thx

[chessie4905]

I have a new sending unit fr my coach. I'll get you the part number and check the ohms for you. I'm out of town now, can get it probably Wednesday.

[Decalsbyblondie]

You do  Not need to remove the tank to remove the sender, it has been my experience with 16 coaches and one motor home that a fuel gauge will work for about two weeks and then randomly,  much easier to use the 500 mile deal

Better safety than empty

[chessie4905]

Checked out the gauge today.It is deeply stamped 90 ohms. One terminal, 5 unevenly spaced holes, main body sticks 16 inches down in tank, float arm is 16 inches c to c. Unfortunately, part number is no longer legible on box. Decals is correct; sender can be replaced without removing tank. In from end of tank about 10 1/2 inches. You will need to remove access plate in floor.

Here is a source for sending units, probably one of several.
http://gaffrigperformance.com/117-Fuel-Level-Senders