The Lab Rat - SFR's R&D Comanche

[IslanderOffRoad]

Assuming the fuel gauge worked with the old cluster? Could be a stuck float

 

[JohnX]

If the old one worked, and the new one doesn't then I'd have to say it the new gauge. Easy enough to test....remove the sender wire from the tank, gauge should sweep one way. Ground that wire(good clean ground), and the gauge should sweep the other way. If it does that then the cluster and wiring is okay, which leaves you with an issue at the float.

 

[StinkyFab]

Old gauge worked perfectly 5 minutes before this cluster was plugged in, so the chances of there being a problem with the float are next to zero. Just wasn't sure if there were different senders at play here causing the problem.

 

[StinkyFab]

Well I got it working. Pulled the cluster back out and cleaned all the contacts then plugged it in again and it was happy. As I pushed the cluster back into the dash it went dead again though. Seems like the harness was getting pushed sideways or something and breaking the connection. I moved the wiring around to a better spot and it seems happy now.

 

[GSequoia]

Clearly not your issue here since it's already solved but there are fuel sender differences.

1987 - 1990 XJ
Empty 1 ohm
1/2 44 ohm
Full 88 ohmSource: 1989 FSM

1991 - 1996 XJ
Empty 105 ohm
1/2 33 ohm
Full 5 ohm
Source: 1993, 1995, 1996 FSM.

1997 - 2001 XJ
Float down 270 ohm
Float up 20 ohm
Note: This may not be the actual full and empty positions. The 1997 - 2001 FSMs do not lay the resistance values out the same as the earlier ones.
Source: 1999, 2000, 2001 FSM

ZJ
The only ZJ book I have is 1993:
Empty 105 ohm
1/2 32.5 ohm
Full 5 ohm

 

[StinkyFab]

Given that the 2 clusters are from the same year there shouldn't be a difference there then. I was mainly concerned that the senders were different based on the cluster, just like the oil and coolant sensors are different. That doesn't seem to be the case, Good tech to have though!

 

[GSequoia]

Understood, I did all that research for another post awhile back and figured I could make myself look smart twice for the price of one.

 

[rockclimber]

Understood, I did all that research for another post awhile back and figured I could make myself look smart twice for the price of one.

you'd have to post under someone else's account for that.

 

[markw]

you'd have to post under someone else's account for that.

Where's the like button? Nice write up Dallas.

 

[StinkyFab]

Not much to post about the build recently, I've just been driving the truck a lot. One big reason for picking an MJ to build was to have a shop truck, and this thing has been serving us very well in that role.

A couple weeks ago however I took a trip out to the Hammers with Cal and a bunch of other so-cal people and got some good testing video of our aluminum steering parts. This was taken on my other rig, which has crossover steering with heim joints, but is otherwise the exact same as our production 1-ton kits as far as material and design. I built this setup roughly 6 years ago and it's seen an awful lot of this kind of abuse, with just scrapes and scratches to show for it.

 

[rockclimber]

did you purposely point it dead center at every rock? .!..!.

 

[StinkyFab]

I never claimed to be a good driver

 

[VAhasnoWAVES]

i love driving by braille.

 

[90xj06]

all that squeaking makes me cringe. just looks like something will break.

 

[cal]

thats just the sound of awesome slipping out of the joints while it moves.

 

[StinkyFab]

It's also greatly magnified by the camera being mounted to the frame. It's not really all that squeaky in person, but there are a few poly bushings in my suspension that'll drive you crazy LOL. Also one of the upper ball joints is toast. I'll fix it someday, but since this rig pretty much lives either in the dirt, in the garage, or on a trailer I'm not all that worried about it.

 

[PhotoJared]

OH MY GOD. I think you went out there just to scrape up your axle and tie rod.

Show off lol

 

[cal]

OH MY GOD. I think you went out there just to scrape up your axle and tie rod.

Show off lol

no, he really drives that way.

 

[rockclimber]

watch from 1:15-1:33

with a normal steel tie-rod both rocks in that section would have held the rig up, the Alum tie-rod just conforms to the rocks and keeps going.


Dallas,
have you considered going OTK with that tie-rod? or do you have it slung low like a sort of off-road "curb feeler" :laugh:

 

[StinkyFab]

I can't run it OTK on that rig because at full compression it would hit the sector shaft on the steering box. Trust me, I'd love the extra clearance, but I love suspension travel more.