91 740 turbo wagon engine cuts out when gas is at 1/8 tank?

[redlinegw]

I noticed that when my gas gets down to about an 1/8 of a tank the engine cuts out then comes back on. I notice it most when I come to a stop. Is it most likely the pre pump? Any other ideas?

[TrickMick]

do the MATHS *first*...how many gallons to FULL FILL
(fuel peeking at you in the filler neck)....run it down til it
starts playing up and then *refill* to same level...is it REALLY
an "eighth of a tank" or is your gauge lyin' like a rug???
no messy / not smelly / not fuel dangerous games...just a
pencil and paper *FIRST*... it true...THEN do tank work!

[lummert]

I for one keep my tank filled at least to half full to prevent problems like this.

[redlinegw]

Thanks I will go fill the tank now since it just happened and see how many gallons it takes.

[ikyikthe1st]

As Mick said, it is quite possible the gauge isn't correct...the feelers that ride up and down on the assembly can degrade and mine eventually got stuck in one position.

[redlinegw]

It took 14 gallons to fill it and I went 204 miles. 14mpg around town sucks I get at least 19 out of my S60R doing mostly around town driving. Something must be up with it, I would think it would get at least 20mpg.

[TrickMick]

Originally Posted by redlinegw

It took 14 gallons to fill it and I went 204 miles. 14mpg around town sucks I get at least 19 out of my S60R doing mostly around town driving. Something must be up with it, I would think it would get at least 20mpg.

in a TURBO CAR that long thin pedal on the right next to the tunnel
is called a HAPPY PEDAL.....you push it and get HAPPY...(but you DO
pay for the happiness w/crap mileage.. )

check the files for "mileage threads"..you'll find the range is 14 to 20
so "yer in the right ball park"....

SWMBO runs an N/A 1991 244/AW70 and gets CONSISTENT 28 / 30 mpg
I run a "tweaked" 1991 244/AW70 and get 25 if I've been a "good boy"
21 if I run "thrasher style".....

if yer gauge is correctemundo then follow :lummerts lead" and keep a half tank....
when you have the time and DO$H go ahead and replace the "in tank godies"
use the SAE spec SUBMERSIBLE hose on the little stub SAE 30R 10...

[atrokz]

Same problem as you, only:

Once in a while AFTER a fill, the gauge will drop to E (light on and all) and then back up to full. It did it about 3 times in a row, then no problems at all. Seems like the feeler/gauge sender is sticking as well, but this is strange.

I just keep it fairly full most days. Rarely let it go low. I think it *may* have something to do with a sticking sender (from previous owner letting it sit over winter without a fogging) in addition to a preforated pick up hose.

[BrickBaller]

I get 21 on mine, 24 if I baby it everywhere (hard to do for a full tank) and around 17 with the happy pedal used often.

Gas gauge doesn't work at all

[ray b]

Originally Posted by redlinegw

I noticed that when my gas gets down to about an 1/8 of a tank the engine cuts out then comes back on. I notice it most when I come to a stop. Is it most likely the pre pump? Any other ideas?

do the newer 740 share the 240t problem with the fuel line intank rotting

there is short bit of rubber fuel line from the submerged pump up to the tank outlet
on my 83 240t the line split a line and was way off power at a low tank

anyway a cheap fix and not too hard to pull the pump/sender/line out the top

[redlinegw]

Well something is definitely up with the pre pump or something I only put on 213 miles and it started cutting out again. I went and filled up and it only took 13 gallons so I got 16 mpg and this time I did mostly highway miles I am taking the car to the wagonmeister in a couple weeks to have a IPD turbo cam kit installed so I guess I will have him diagnose it further. I will let you know what I come up with.

[lummert]

Driving 213 miles on a tank is taking chances in my experience with my 88 765.

[brickyard92]

There are two marks on the edge of the tank stalk top, where all the hoses are clamped, that align with the weld seam in the gas tank. If for some reason the stalk is not in alignment, the pickup tube will be higher than the bottom of the tank and not allow for the use of a full tank: more gas will be left at the bottom that can't be sucked out.i had this issue it took me 2mts to figure it out.there's a link for this issue on brickboard .com.i hope this is the issue that you're talking about.

[redlinegw]

I will check out thanks! There was no link though

[brickyard92]

i'm working on it.i'm not computer savy at all lol sorry.

[brickyard92]

Here's the link redline i hope you found it before i did ..http://http://www.brickboard.com/FAQ...#TankAlignment

[redlinegw]

That helps thanks,

[TrickMick]

Originally Posted by brickyard92

Here's the link redline i hope you found it before i did ..http://http://www.brickboard.com/FAQ...#TankAlignment

http://www.brickboard.com/FAQ/700-90...eplacement.htm ??

I couldn't find the "alignment" bit you referred to..can you repost and CHECK
the link before you unleash it??

TIA for any help!

[496truck]

This pic shows the 2 marks pretty good, they are at 9 and 3 o'clock.

[redlinegw]

I think this is the correct link: http://www.brickboard.com/FAQ/700-90...#TankAlignment

[brickyard92]

Yep,thats it .

[lummert]

Originally Posted by 496truck

This pic shows the 2 marks pretty good, they are at 9 and 3 o'clock.

On this type sending unit with the plastic base the marks are easily found. But on the earlier metal sending unit base the marks are sometimes not easily found.

[redlinegw]

I heard it is a real booger to change the pre pump in these sucka's :(