Recent posts

#11

Mechanicals / Re: Force close warm coolant t...

Last post by Jan S - Yesterday at 02:40 PM

It's one of these as far as I recall.

Thanks - my to-do list gets longer 

Also known as the central locking master cylinder, and a well known source of leaks.

Thanks - good to know!

#12

Test Drive / Re: 4000 km road-trip and cont...

Last post by Jan S - Yesterday at 02:37 PM

Perfect and thanks to both of you for inspiration - several items on your lists I will bring with me!

Mercedes Benz Museum and Classic Center, Fellbach - here he comes!

#13

Mechanicals / Re: Force close warm coolant t...

Last post by ptashek - Yesterday at 09:30 AM

Also known as the central locking master cylinder, and a well known source of leaks.

#14

Test Drive / Re: 4000 km road-trip and cont...

Last post by ptashek - Yesterday at 09:29 AM

Fluids, and fuses, maybe jump start cables depending on the age of your battery. Maybe a set of spare belts if not replaced already. Spare bulbs of all kinds.

Other than that, you're never far away from help in Germany, so I'd just relax and go for it.

#15

Test Drive / Re: 4000 km road-trip and cont...

Last post by daantjie - Yesterday at 09:06 AM

Spare coolant
Good long breaker bar
Good flashlight with extra batteries
Headlamp
Rags and hand wipes
Gloves
Smock or old blanket you can lie on if you need to look/work underneath
Emergency triangle

Then I always keep a jug of drinking water in the car just in case.

#16

Test Drive / 4000 km road-trip and continge...

Last post by Jan S - Yesterday at 08:15 AM

(The car is a 1975 US 450 SE with a 1977 US 6.9 engine)

I'm planning a 4000 km (2500 miles) road-trip this summer – Norway and Germany.
I have done a fair bit of work on the car the last two years, replacing many parts and checking things. The car is running great, at the moment, but I must admit the trip is a nervy endeavour ... the car is close to 48 years old.

I'm planning to take with me:
- Engine oil
- Transmission oil
- A couple of "ice-cube" relays
- a spare tyre, a jack and all that ...
- "emergency" tool kit, including tools to close the sunroof manually

Anything else I should add to my list? Any suggestions/advice?

#17

Mechanicals / Re: Abrupt K-jet wierdness and...

Last post by Jan S - Yesterday at 07:40 AM

Uh oh, I spoke too soon.  Pressures seem to be OK, car starts, but after about 30 seconds she starts stumbling and eventually stalls.  So, some improvement, but problems remain.  Back to the drawing board....

- Return flow ok? Approx 1-1.5 liter/min?
- System pressure approx 5.5-6 bar?
- Control pressure approx 1 bar cold and 3 bar warm?

(these are not exact specs, but in the ballpark)

These three things need to be ok. 

#18

Mechanicals / Re: Abrupt K-jet wierdness and...

Last post by daantjie - 26 June 2022, 01:56 PM

Maybe something to do with tank venting system?  Not sure really just thinking out loud.

#19

Mechanicals / Re: Abrupt K-jet wierdness and...

Last post by raueda1 - 26 June 2022, 12:54 PM

Uh oh, I spoke too soon.  Pressures seem to be OK, car starts, but after about 30 seconds she starts stumbling and eventually stalls.  So, some improvement, but problems remain.  Back to the drawing board....

#20

Mechanicals / Re: Abrupt K-jet wierdness and...

Last post by raueda1 - 26 June 2022, 12:27 PM

Progress??  A couple years ago I rebuilt the fuel distributor.  Reassembly had catastrophic results as many here will recall.  Apparently I made another mistake as well by swapping the FD fuel line and return line fittings.  Unknown to me, and not referenced anywhere I can recall, there's a tiny screen filter inside the fuel supply line fitting. The return is clear.  Mine were reversed so fuel return flow had to push past the filter on its way to the tank.  I'm sure somebody will point out that this is well documented, so this is just my most recent stupid mistake from not digging deep enough. 

Anyway, I compared flow with another fitting from a clean FD.  The blow-through-the-filter test showed that the spare fitting filter had much, much freer flow than the original, which was substantially occluded.  But this doesn't entirely explain why the pressures would suddenly go crazy after running great for 2 years.  My theory is that  the return filter collapsed slowly at first and then suddenly.  I had noticed a gradual performance decline over the last few weeks, but car still ran.  Then, abruptly, it scarcely ran at all.  I think all this isn't totally crazy, cause the filter element is sock-shaped.  When installed in the fuel return circuit the fuel flow would be reversed, compressing the filter sock against itself.  Close examination of the respective filters supports this idea.  The filter sock in the bad one was indeed collapsed on itself.  So, now to install the fittings correctly and retest.......  >>drum roll<<

That was it!  Pressures back to normal!  Impeded return fuel flow was indeed the culprit.  So we now know for sure that filtering the fuel return is a bad idea.  I'll never do that again.   And neither should you.  Case closed.  Thanks as always and cheers,