dr bob

Fellow Shark Chums...

I recently replaced the oil sump gasket on my '89 S4. The rubber boot that protects the connection on the oil level switch is crispy, and didn't survive removal unfortunately. What are folks using to replace the boot these days? I've seen mini battery terminal boots used in the past, but wonder if anyone has found a better and closer-to-original-appearance cover.

For reference, the oil level switch is located in the front of the sump on the left side, with the connector on the little duckbill section. "Left" is driver's side on US cars. The wire for the switch is part of the front of engine harness that terminates at the 14-pin connector on the right side fenderwall by the jump post.

I also noticed for the first time that the wire itself is getting a little stiff too. At some point in the maybe near future, that whole harness will need to be rebuilt or replaced. In the meanwhile, a good replacement boot/cover is needed. All suggestions are appreciated.

FredR

Bob,

My wiring around the 14 pin connector was toast a year or so ago so I had to replace wires from the oil pressure sender, the oil level switch, the a/c solenoid and the voltage indication from the alternator. Did this by using good quality 1mm2 wire available locally but not with the correct colour combos- just made a sketch with the colours used and attached it to my wiring diagram sheet.

For the level switch I resued the connector but had no obvious solution for a cover so wrapped some self vulcanising tape over the terminal- seems to work OK but not concours material! Doubtless you should be able to get correct colours and something more elegant for the cover in your neck of the woods.

Incidentally, I ran those wires routed separately to the main loom that I did some repair work on pending a complete replacement in the not too distant future [all being well].

Rgds

Fred

soontobered84

Dr. Bob,
I believe that Roger has been trying to source that particular rubber boot for several years, but to my knowledge has not found anything close to a match. Therefore, the search continues.......

ROG100

I have tried lots of alternatives with zero success - any ideas that work will be well received.
Personally I wrap the connection with RTV tape which has proven successful if not exactly stock.

dr bob

There are more than a few PVC "terminal covers" available that, unfortunately, won't survive in the environment, and won't look like the original. I've found a couple that are rubber and may fit, but I need to uncover the car and get some dimensions to see if any of them will actually fit. The actual connector will need to be removed from the wire and refitted after the the wire is passed into a new boot, another bit of fun since it will need to be done in place.

In the meanwhile, a bit of shrink sleeve may be an interim solution. I hate doing "interim solution" fixes because they have an annoying habit of becoming permanent unless managed carefully. Too soon, the car becomes a patchwork array of "interim solutions". Since I have a few months of winter hibernation period to solve the problem, hopefully "no interim" solution will be actually needed. I do still need to dive in for some dimensions though.

Rob Edwards

The boot is Bosch # 1 280 703 007, here's a new one on an NOS harness I got from Mark:



Googled around for this a while back and came across a guy in Germany who makes a reproduction boot for Mercedes D-jetronic injection systems. Not sure whether it's the same boot but it looks awfully similar:

I meant to get in touch with him to see about getting some but didn't get around to it. Would make the most sense for Roger to reach out and maybe get a volume discount (?)

http://repro-parts.de/

davek9

Wow so that is what a new one should look like, never seen that bottom tapered section intact, thanks for posting it.

There is an "aftermarket" boot installed on one I have and it looks close, I'll take a pic and post it up later here.

hwyengr

I was googling too and came across repro-parts via a MB maintenance site. If you note down in section 10.2 of https://oldtimer.tips/en/d-jetronic/wiring-harness, that group specifically custom-ordered our boot by the Bosch part number, so if repro doesn't sell it now, they once did and maybe could be convinced to do it again.

Rob Edwards

A little more digging finds that 1 280 703 007 used to be Mercedes' part number 000 546 15 35, which supercedes to A0005462035. But the pics of _that_ part number don't look anything like the original, it's rectangular in section rather than round.

GT6ixer

This could be reversed engineered and 3D printed to a high degree of quality using either nylon or a rubber-like resin. I have made a few samples of other parts for Roger and he has seen the detail that is possible with high end industrial printers. I'd be happy to do the reverse engineering on the boot if someone can let me borrow one for a few days.

Rob Edwards

Nate, I'm not sure I can get this one off non-destructively (nor do I really want to try), but I might have a used one that's intact but cooked- if so, if I sliced it off and glued it back together, would that work as a template/model?

GT6ixer

Yes. in fact the used one is even better. Don't glue it back together. I'd like to see the inside surface. I'll shoot you a PM with my address.

After I get the surface in CAD I will print out a few prototypes. I can print in Nylon from home. I'll have to out source the rubber version, which I believe will be the best surface finish and perhaps the most usable material.

Kevin in Atlanta

Take a look here: angled temp sensor sleeve

I believe they reproduce the part - # 4479000.





Roger, how's your German?

ROG100

My German is great because Schocki looks after my 928sRus business in Germany 8>)
Thanks for all the suggestions and cross references and I will follow up on it tomorrow.
Fingers crossed.

vze2jshn

Hi Roger,
It would be greatly appreciated if Schocki could also check for the boot that covers the wires that go into the spark box.