largecar379

more CIS info:

after doing some more research on injectors, I have found that Witchhunter in WA does offer injector cleaning (not rebuilding) for about $17 per unit. HOWEVER, their website says they do not service CIS injectors.

Lowest price I've found on the 0437 502 012 units is about $44 each, new.

I did find a similar Mercedes Benz injector, 0437 502 047 (they are brass units), that a place in AZ sells for $27.90 each, new.

These injectors are supposed to be upgrades from the steel units (lower numbered--ex: 09, 012 , etc) used in other MB's of that vintage.

One caution note from Bosch on using other than an 057 on turbo'ed models--don't use anything other than recommended OEM units for turbo'ed models due to the threading/holder being different to keep the injector from blowing out of its holder under pressure.

Questions:

Has anyone out there used the 047 injectors in a 928? Are there any drawbacks to using these? do they flow the same or better than the 012's?



thanks for the help-----Russ

largecar379

my quest for injectors has led me to purchase a set of 047 MB injectors (off of eBay, no less) that have been cleaned.

the set went for less than $60 for eight, so even if they aren't perfect it beats the heck out of $220 plus shipping for a new set.

they'll be here next week----

---Russ

largecar379

update:

researched many sites for injectors.

found MB injector 047 at a parts house in AZ for $27 new.

found same 047 in a set (cleaned) on eBay for less than $60.

the 047 injector is shorter than the 928 OEM, but does the same job.

shipped on Friday, here today.

installed this afternoon and what do you know?

runs like new----smooth idle, crisp throttle response----holy cow!!!

thanks for the help---the fix was in the injectors.....reworking the injector lines had to have helped as well.....

---Russ

jpitman2

care to advise on length difference?

jp 83 Euro S AT 51k

SMTCapeCod

Huh, great improvisation.

Photo= a lot of words regarding fitment.

Someone posted a telephone number for Bosch Technical assistance-- might be a good time to give 'em a shout for specifics on spring seat pressure and flow capacity of the two injectors?

largecar379

the length difference between the Porsche OEM injectors and the MB 047 is approximately 1/2 inch.

I have no clue as to flow rate differences, but the car runs great now.

considering the (used, but recently cleaned) MB injectors were $58 delivered to my front door, it was a good buy.

might give Bosch a ring and see what they have to say about it just for kicks-----


--Russ

largecar379

photos would be good, but every time I try to upload one, it tells me the pics are too big. (and I'm not literate enough to try to work around that...)

At any rate, the MB injectors look the same as the Porsche injectors, except the MB injectors are brass and 1/2 inch shorter than the Porsche injectors.

The MB units fit the same as the Porsche units. Seals are the same, seal location is the same, external fuel lines hook up the same......

have I left anything out?

it runs great!

thanks---Russ

jpitman2

I was pretty sure I had read opening pressure was ~50psi....
jp 83 Euro S at 51k

largecar379

on which injectors? the Porsche units or the MB 047 ?

---Russ

SMTCapeCod

Wonder if there will be any issues from differential metals causing electrolytic corrosion (brass and the magnesium alloy intake bits...if the injector cuffs are that).

Dennis Wilson

SMT

The type metal should not have a long term effect since the seals are rubber. If they physically fit and have equal or larger flow rates they should be good since the actual flow is controlled by the distributor.

The opening pressure on most if not all CIS injectors is about 3 bar (45-50 psi). EFI injectors may be 15 psi.

Dennis

largecar379

thanks for the info on pressures, as I was not sure.

the MB engine that these come from uses and aluminum intake as well, so I don't foresee that the metals would be a problem.

---Russ

jpitman2

IIRC the only metal contact between injector and cap is the hex part, and its not tight enough to corrode, and shouldnt be getting much water on it in normal operation, so I think thats a non issue. Worth knowing they are around, and if they perform ok, a good backup source. Next time I am at my Wrench's place I will see if he has any old 911 injectors and check their length against 057.
jp 83 Euro S AT 51k

918-S

interesting topic.. I love work a rounds.

Rebuilt injectors 29.99 listed here. Same part # 0437 502 012 listed for the Saab 1989 900.
928 also listed for 29.99

http://www.fuelinjector.citymaker.co...ge/5133241.htm

Mrmerlin

did you change out the fuel filter before installing the new injectors?? If not you should