DJet Fuel Pump - PeachParts Mercedes-Benz Forum

meltedpanda · #1 10-11-2012, 03:59 PM

I feel led to get Pearl a new fuel pump. Have had some angst about some of the noise the old one is making. It is well, over 40 years old, I think it is getting tired. Like me

So where does one get a DJET fuel pump. I heard Bosch was putting one out but can't seem to find it listed

alabbasi · #2 10-11-2012, 05:33 PM

Ron

Those pumps can be overhauled. They come apart in three parts and you can clean them out. I think new ones are around $500, but you can buy airtex brand from advance auto for about $200. I'd leave well alone if it's working.

irshmerc · #3 10-11-2012, 05:38 PM

I think MBGraham mentioned Bosch doing a replacement pump somewhere, i'm scared to look on the Bosch site, they are bound to be up there with the price of a kidney or other vital organs.

Good luck

97 SL320 · #4 10-11-2012, 07:43 PM

If the fuel pump is original, it is getting very close to failure.

Given D jet is low pressure, I'd be tempted to use a commonly available FI pump. Also take a look at Porsche 914 , VW , Volvo , Jag offerings as they were D jet.

rowdie · #5 10-11-2012, 08:30 PM

Give Graham a shout out. There is also a '79? Nissan pump that has the correct specs and bolts up.
The problem with rebuilding is sourcing the 2 O-Rings in the right size and material. The airtex brand requires adapting.
It appears the Bosch replacement is 0580464999
ELECTRIC FUEL PUMP 0580464999 (1381733)

meltedpanda · #6 10-12-2012, 11:34 AM

thanks all , yes I remember now that Graham did have a replacement , non Bosch.
Was running the other day , after a cold start, running perfectly , then just stopped. waited a few seconds , restarted and then sputtered and then back to normal , no trouble since. Suspect fuel delivery , or at least it felt that way, but also am going to make sure AAV is working , could have been stucK??

I love the Djet lol

97 SL320 · #7 10-12-2012, 12:40 PM

Aux air valve is for cold idle speed control, once warm the valve is completely closed. ( At least the VW units did.)

Fuel pumps do not " Make " pressure, the restriction imposed by the regulator makes pressure. So, if you had a pump from a CIS car it would work just fine. There is one consideration however, most pumps have a pressure relief to prevent overpressure if the filter is clogged / line gets crimped and the CIS pump will have a higher pressure.

Some 80's Fords had a frame rail mounted pump ( in addition to the in tank transfer pump.) that would be a good candate.

rowdie · #8 10-12-2012, 03:26 PM

Pearl deserves better than a Mickey Mouse adaptation of the wrong pump.

The AAV would not cause it to suddenly die. It could be the FPR or even the pump as you said it is making noise. Those are the first things to check IMO.

Graham · #9 10-12-2012, 04:36 PM

Quote:

Originally Posted by rowdie

Pearl deserves better than a Mickey Mouse adaptation of the wrong pump.

The AAV would not cause it to suddenly die. It could be the FPR or even the pump as you said it is making noise. Those are the first things to check IMO.

Agree with Rowdie on the pump!

Those Airtex or other no-name pumps, and the pumps for the later model SLs do not have an integral relief valve. It is there for good reason. The Djets use hoses and clamps on the fuel system. Anyone know what pressure those would give way at? I don't know, but I suspect 50psig would be max. Therefore pump should relieve pressure below that. With a non-Djet pump, you could blow the hoses off and maybe collect insurance on the car when it catches fire

The new Bosch pump is 0580464999 as Rowdie posted. Whether you can find one here, I don't know. They do show up on eBay and elsewhere in Europe.

The other pump, is also a Bosch, but it is/was made in Japan. Apparently it is imported by Bosch USA - Bosch in Germany didn't even know about it, but later confirmed it was genuine.

Feeling Deja Vu

OK here:
Fuel pump alternative on a 72 450SL

I think the pump I have is Bosch 69612. A number of the parts places have it listed, but do they have them? I used Datsun 280z for search. Sometimes needs Nissan 280z.

NAPA AUTO PARTS

If you search for a 1972/3 Mercedes 450SL, the pump doesn't come up. I asked Bosch Canada and they said it was the wrong pump. But I don't think they are right. I have the new pump here in box and it is identical to the OE pump. It even has the proper MB Bosch number on the box.

I would say that first choice would be the new Bosch DJet pump (maybe ask Tom Hanson at Classic Center what they want for one) or buy the Datsun pump.

It would be possible to jury rig an external pressure relief, but probably not worth the effort. Just fork out the $500 or so and get a proper pump. I did some years back, but it is still in box.

My 40 yr old pump works fine. There is really nothing much that can go wrong with them. I did take mine apart and flushed it out, but it was clean. I re-used the o-rings. They were in good shape. I did a pump flow test and it came out close to specs. (Disconnect return line to tank from FPR/Damper, jumper relay or connect power directly to pump**) and see how much you collect in 30sec or how long it takes to collect 1L. Should be 1L in 30sec.
** Pump will likely pump at different rate using external power because pump speed/volume is proportional to voltage. Check that you are getting 11.5V or more at pump.

If car is stuttering intermittently, I would look for electrical problems first. Then filter and tank screen. Maybe swap a couple of relays (They are apparently all the same)

meltedpanda · #10 10-12-2012, 08:41 PM

thanks guys, correct Rowdie, no jury rig here, talking to a guy on ebay has a NOS pump , but has not tested. He is in process of checking to see if it spins. what do you all think about a NOS pump that has been on a shelf for 40 years, any internals that could dry rot?
As far as the stutter and die - really "felt like" fuel delivery so I am checking those possibilites. Rowdie was kind to send me a relay a while back, I'll swap that tomorrow, and fiddle with stuff...as I do

DieselPaul · #11 10-13-2012, 09:42 AM

The two trianglar o rings get rock hard. If he is taking it apart to see if it springs it'll probably start leaking.

Graham · #12 10-13-2012, 10:08 AM

Quote:

Originally Posted by meltedpanda

thanks guys, correct Rowdie, no jury rig here, talking to a guy on ebay has a NOS pump , but has not tested. He is in process of checking to see if it spins. what do you all think about a NOS pump that has been on a shelf for 40 years, any internals that could dry rot?
As far as the stutter and die - really "felt like" fuel delivery so I am checking those possibilites. Rowdie was kind to send me a relay a while back, I'll swap that tomorrow, and fiddle with stuff...as I do

I checked eBay and found a guy that had three and had a Buy-it-Now of over $500.

I imagine those pumps would still be OK - The o-rings are well sealed. Electrical lead insulation may have dried out.

Perhaps you can find a more recent pump for less if that is the one you are looking at? Mind you, I paid over $500 for the Bosch 69612 spare I have.

This looks like the same pump:

Motorsport! Electric Fuel Pump, 75-83 Z/ZX Non Turbo - The Z Store! Nissan-Datsun 240Z-260Z-280Z-280ZX-300ZX(Z31/Z32)-350Z-370Z Parts

or on eBay

http://www.ebay.com/itm/280Z-FUEL-PUMP-OEM-GENUINE-NISSAN-1975-1978-/230863721937?pt=Motors_Car_Truck_Parts_Accessories&hash=item35c08cd5d1&vxp=mtr

Looks like Nissan part number is 17011-P7211 - Lots of hits if you search for that.

meltedpanda · #13 10-13-2012, 10:34 AM

Quote:

Originally Posted by DieselPaul

The two trianglar o rings get rock hard. If he is taking it apart to see if it springs it'll probably start leaking.

no just 12V to see if she spins

and thanks Graham, I'll check it out

meltedpanda · #14 10-14-2012, 04:15 PM

Try as I might , could not reproduce the symptoms. Check function of AVV and its fine, no vacuum leaks,
guess I'll wait it out see if it happens again. Sure seemed like fuel delivery..
gotta love these ol gals

cushjbc · #15 10-15-2012, 02:28 PM

Melted,

I pulled one of those Japanese Bosch fuel pumps from a '74 W116 at U-Pull-&-Pay in ABQ last week. I have no idea how long it had been installed, but I salvaged it on its second day at UP&P. It had stale fuel in it when I pulled it. I put 12V through it last Thursday and it runs. I have not tested it with fuel.

I was going to use it to make a test rig for injectors but would rather see Pearl running smooth. Especially if that makes you keep her. PM me if you want to chat about it.