Before you blame the Sender

Southernboy

Zorg Guru (II)
3rd Party Trader
Joined
Apr 27, 2012
Points
100
I bought a project Z3 around January time. I drove it from Cape Town back up to Johannesburg without a functioning fuel gauge... scary stuff with lots of fill up stops.
Since then, I have had the fuel pump / sender out no less than a dozen times. A previous owner had obviously had a go at sorting out the common Z3 / BMW fuel gauge issue - erratic or non functioning display on the cluster. In the process he had broken one of the small clips which holds the housing carrying the float arm and ceramic card sensor. When I first removed the unit, I found a cable tie holding it to the main body housing the actual fuel pump..
I bought a new replacement ceramic sender card, and using a broken unit for the part that holds the ceramic card and the float arm, I replaced the plastic clip on housing which holds those components.
Prior to buying a new ceramic card, I had had the pump out to replace the broken housing as described above, I refitted the unit but still had a zero reading on the cluster gauge. After several attempts at cleaning the original card with rubbing alcohol and using 2000 grit paper on the two little sprung contacts which ride across the ceramic card, I still had a flat liner... That's when I decided to replace the ceramic card.
When that arrived, I pulled the unit again, fitted the new card and..... still no cluster reading.
Pulled it again and found another assembly error from the previous owner. The two sprung contacts have a very specific way of being housed - he hadn't refitted them correctly. So, that sorted, I re-fitted the unit, but again nothing.
Today I pulled it for the last time. I had checked all the connectors, the wiring from tank to cluster and the ceramic card for correct operation and resistance reading on my multi-meter. Everything was working including the cluster gauge which I had taken in to a specialist repair shop for testing.
Finally I had a good look at the fully assembled unit, and I noticed on the inner side, there is a small round plastic button covering a little rubber diaphragm. I popped the little button off, removed the rubber bit and managed to easily thread a piece of cotton through the hole which emerges at the upper hose connection on the outside of the unit. I then tied the inner side end of the cotton to the float and popped the unit back into the tank.
I didn't replace the screw on nut thingy, but lined it up as per the mark at the bottom, and pulled on my piece of cotton which raised the float arm inside the tank.
The cotton managed about 20mm before the float arm got stuck inside the tank.
That was the beginning of 3 hours of trial and error bending the float arm one way then another and checking by putting the unit back into the tank each time to check if it would move freely.. finally I found the right combination and for the first time since I got the car I have a fully functioning fuel sender. Cluster gauge is working 100%. I checked by filling the tank in 4 stages.. 1/4 at a time and each fill reflected the correct reading on the cluster.
If anyone else is suffering you can PM me an email addy and I'll mail you a "how to" with a photograph of the required bend alteration to the float arm.
 

Southernboy

Zorg Guru (II)
3rd Party Trader
Joined
Apr 27, 2012
Points
100
=))..... Thanks. I'm now looking for the source of a rattle at the back.. Been at that one for a few months without success..:(
 

Grumps

Always happy, apart from when I'm not 🤬
Supporter
British Zeds
Joined
Apr 27, 2014
Points
226
Location
Forest Town, Mansfield
Model of Z
Z4 e85 2.5i
Do you still have Scarab 2 Barry? Can we see the new one?
 

Southernboy

Zorg Guru (II)
3rd Party Trader
Joined
Apr 27, 2012
Points
100
Hi'ya buddy.
Yes still got II... I'll post some pics of Blueberry in the next 2 weeks.
I'm fitting a new roof this weekend, and then week after next it's at the paint shop for glazing.
Once that's done, there's just a new windscreen to be fitted, Might get that done next week depending on time.
I'll post the before and after shots. This car was a bit of a wreck when I got it.
New shocks, new discs, 4 new tyres, new DISA, new MAF rubber parts connecting to the throttle body, new CVV valve with new pipes, blower fan resistor removed, cleaned and re-fitted so it works on all speeds, new wiper blades, new badges, new bonnet grill, new fogs, new park and side lights, complete re-vamp of all interior plastic components, new gearbox and diff, new driver side door mirror glass and mirror motor, new driver side seat adjustment switch and related plastic seat trim, the entire interior was removed including dash for re-finishing, new seat bushes and all parts cleaned and fresh grease applied, all lubricants and coolant, fresh brake fluid and power steering fluids, new boot lid, driver door innards re-welded, boot welds done, complete OEM tool kit, both keys re-chipped and coded, both door cards fitted with full compliment of clips and clip mounts, two new front wheel arch liners, new interior dash top leather, all interior leather re-dyed, cluster and console bulbs fitted where not working, headlight lenses re-surfaced polished and uv sealed, 3rd brake light sealed with silicone sealant, all 4 indicator bulbs re-newed, new OEM front bumper / spoiler grill, new front floor mats with OEM floor clips, all OEM clips fitted where missing to under dash / foot well trim. Cigarette lighter re-furbished and re-connected, new front door sealing rubbers, new plastic trim pieces along the bottom interior of both doors, and all manner of small odds like missing trim screws replaced, and a full body repaint and clear-coat job.
7 months of weekends and nights cleaning, polishing, scrubbing, restoring and re-fitting... been quite a journey with sourcing parts from Japan to Europe to UK, USA, and Europe.
Not cheap considering the local currency is around 18 to one £, plus duties and 15% VAT.. All good fun though even if sometimes I cursed my decision to buy the car. I think the worst was finding a replacement gearbox which was in perfect working condition, and then a diff that didn't whine. Some parts were an absolute bargain mostly sourced from another Z3 owner whose son forgot to hit the brakes before the tree.. He bought a scrapped car as a donor vehicle, and had quite a lot of stuff I needed and which I got at truly bargain prices.
The roof is as near as OEM as one can get and comes with all the sewn in plastic trim bits which hold it to the window surround sections. The only non-OEM aspect of it is the rear window isn't a zip in, but other than that it's precisely the same as OEM including the fabric.
US$ 375 excl shipping etc from Sierra Autotops and Seats. Nice thing is they also have a full instruction / fitting guide on removing the old top and fitting the new one - complete with photographs of each step - very professional outfit.
And finally as described previously, the fuel pump / sender issues...;)
 

Southernboy

Zorg Guru (II)
3rd Party Trader
Joined
Apr 27, 2012
Points
100
I did consider a progress / re-build thread, but then thought better of it - enough PT just putting the car back to a complete specimen worthy of being a Z3 and making it 100% desirable should I decide to sell it on.
 
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