Gas Tank and Fuel Gauge

[German Dude]

Folks,
with my new old-style fuel sender in place, the gas gauge is finally working. It is kind of bouncy, but the search has shown me others are dealing with this issue too. I was happy to see that even my low-fuel warning light works.

I did not find anything on a solution to the bouncy gauge - is it just something we old-time-sender-owners have to live with?

In addition: whenever I fill her up, I fill in gas until the nozzle automatic switch-off kicks in (I hope you know what I mean). After that, the gauge shows about 3/4 full. Since I don't want a gush of gas over my feet, I don't keep pumping after shut-off. However, with an about 60 liter tank capacity, I should be able to pump about 15 liters more. I would appreciate to hear about your fill-her-up-strategies.

Thanks,

Juergen
64 230SL #2933, 4sp, signal red, white hard top
93 Citroen XM station wagon

[tuultyme]

I can usually get another about 4 gal and a "full" tank if I bring the nozzle about half way out and slowly add the fuel.  If there is not a lot of other noises around I can here the fuel guggle as it gets close to full.  I also keep the fuel nozzle close to the bottom of the neck.

Bruce; 268Blaugrun(green) 1970 280SL; IL

[J. Huber]

I do exactly what Tuultyme does -- slowly top off until the gurgle. A little gets on bumper no matter what I do. So I have a little paper towel handy. My needle jumps a little except at that very full moment. Another thing: I always attend the nozzle from start to finish -- don't attempt to get it going and do something else. It will fall out, bang the chrome, and make a mess...

Oh and while on the subject, here's a "stupidest things I've ever done with my Pagoda" story. Maybe a good thread (unless I am the only poster...) I was filling up once many years ago. I finished up, went to pay, and drove off. Problem was the nozzle was still in tank! It snapped off and the tip of the nozzle fell into the tank. The mechanics on duty took it into garage bay and used a magnet-type tool to get it out. It took a while but they did it. So do I win the prize or what??  :oops:

James
63 230SL

[hauser]

I just had a new sending unit installed and it works fine.  I have not noticed any bouncing.  At fill ups I try to get in as much as possible without spillage.

1969 280sl 5 spd
Gainesville, Fl.

[n/a]

I am experiencing a similar problem on my '70 280SL Automatic with the fuel gauge.  The gauge seems stable on "Full" down to 3/4 full, then bounces a bit down to half full, and is stable from there until the red light comes on.  I thought about replacing the sender, but thought I'd do a couple of checks first.  With a full tank, the red light does not come on until about 400 km on the trip odometer.  Does anyone else has a similar fuel useage? I wonder how many km I should expect to get to a tank full - more or less than the 400 km?  I would expect a little more, as the engine was running rich.  Comments?

Also, I had the car in for service yesterday and the plugs showed evidence of running rich, which was adjusted.  Also, oil change in the transmission to Dexron 3, and the valve clearances adjusted.  Big difference in operation, engine seemed quieter and "more willing", and a significant improvement in transmission gear shifting.

I just got the car in April, and am still establishing baselines in maintenance, as the car has been sitting for a while.  Surprising (but not really) what a bit of maintenance will do.

It was a very enjoyable trip home from the Service Shop yesterday afternoon, both windows down and the car running well and sounding great.  It was a hot sunny day, about 30 Deg C, no sign of overheating even in rush hour traffic.

As "Rick" (Humphrey Bogart) said to "Inspector Renaud" (Claude Rains) at the ending of Casablanca, "this could be the start of a beautiful friendship".

Jim

quote:Originally posted by German Dude

Folks,
with my new old-style fuel sender in place, the gas gauge is finally working. It is kind of bouncy, but the search has shown me others are dealing with this issue too. I was happy to see that even my low-fuel warning light works.

I did not find anything on a solution to the bouncy gauge - is it just something we old-time-sender-owners have to live with?

In addition: whenever I fill her up, I fill in gas until the nozzle automatic switch-off kicks in (I hope you know what I mean). After that, the gauge shows about 3/4 full. Since I don't want a gush of gas over my feet, I don't keep pumping after shut-off. However, with an about 60 liter tank capacity, I should be able to pump about 15 liters more. I would appreciate to hear about your fill-her-up-strategies.

Thanks,

Juergen
64 230SL #2933, 4sp, signal red, white hard top
93 Citroen XM station wagon

JLHunter

[graphic66]

Check your actual mileage. At my last fillup I had gone 250 miles with 15 gallons, 16.66 mpg. The light came on at about 235 miles. The newer sending units are enclosed in a tube with a labrinth at the bottom to slowly feed and drain gas from the float so as not to have a bouncing gauge. My light would only come on after the car sat for a while. It turned out the labrinth had a little piece of stuff in it partialy blocking it. I cleaned it and now it comes on perfectly every time. I always let it get low enough to come on because I like to see it work. It is better to keep these cars full because the fuel is cooler but I just love that little light. My car is a 230 SL which has a little smaller tank than the 280 or 250 SL.

[Cees Klumper]

Jim - I get just about 400 km on 55 liters. There have been many earlier posts on fuel consumption, and this is a normal average. I believe Dr Benz has the all-time record on getting the most miles out of his fuel.

My fuel gauge does not bounce. To fill it all the way up, I tilt the nozzle forward (so the tip moves towards the rear of the car as far as possible), this will add quite a few liters to the tank.

Cees ("Case") Klumper in Amsterdam
'69 white 280 SL automatic

[German Dude]

Regarding fuel consumption:

Since my gauge went back into business, I have driven two tanks' worth (or 3/4 tanks worth, see my earlier post further down). My light (which I find cool, too, graphic66!) comes on after 420 km. If my math doesn't fail me, it means that she consumes 10,71 liters/100km.
Which I find extremely decent. I should perhaps mention that I don't take her out on the Autobahn. I am more of a 80 km/h countryside kind of guy.

Juergen
64 230SL #2933, 4sp, signal red, white hard top
93 Citroen XM station wagon

[n/a]

I have the exact same condition on my 69 280 SL. Gauge shows 3/4 when full...a little bounce....then steady drop til the light goes on. I learned how to live with it for now.
By the way, what gas grade do you guys prefer? Here in Dubai we have 95 & 98. I used both and the car seems to like 95 better. Any comments?
Thanks
Mo
69 280SL - Silver/Black

[rwmastel]

quote:Originally posted by Mo

By the way, what gas grade do you guys prefer? Here in Dubai we have 95 & 98. I used both and the car seems to like 95 better.

I use the highest available.  Typically, that is between 91 and 93 octane using the (RON+MON)/2 method found here in the USA.  Some countries use RON, some MON, and some the average.

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420