Author Topic: 280SE djet ignition distributor shaft axial play  (Read 828 times)

s class

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280SE djet ignition distributor shaft axial play
« on: 25 October 2017, 01:32 AM »
Hi All,

Fighting with a very nice early Djet 280 at the moment.  The car is a factory 040, with only 70 000km on the odo. 

The ignition distributor has about 2.5mm axial play, spec is ~0.1mm. 

On stripping, it seems the fibre shim washers have disintegrated and disappeared. 

I've heard of the porsche/vw guys substituting delrin washers, but I'm not sure where exactly to shim.

between the drive gear and bottom of the casing?
between the top of the bushing in the casing and the underside of the d-jet trigger cam lobe?

Any help appreciated.  I've checked the manual and it doesn't go to this level of detail .

'76 6.9 Euro, '78 6.9 AMG, '80 280SE, '74 350SE, '82 500SEL euro full hydro, '83 500SEL euro full hydro , '81 500SL

TJ 450

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Re: 280SE djet ignition distributor shaft axial play
« Reply #1 on: 25 October 2017, 04:38 AM »
My blue 6.9's distributor has this issue, so I'd be keen on a resolution to this myself.

Maybe it's worthwhile consulting a Bosch agent too.

Tim
1976 450SEL 6.9 1432
1969 300SEL 6.3 1394
2003 ML500

rumb

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Re: 280SE djet ignition distributor shaft axial play
« Reply #2 on: 25 October 2017, 06:17 AM »
contact this guy - Jeff, he probably knows and may even have the washer

https://www.facebook.com/pg/AdvancedDistributors/about/
'68 250S, '77 6.9 euro, '91 300SE, '98 SL500 '14 CLS550

Guillaume C

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Re: 280SE djet ignition distributor shaft axial play
« Reply #3 on: 25 October 2017, 09:54 AM »
There is a small clip under the felt in distributor shaft. Upper shaft is attached to lower shaft by this clip.

If you had to pull strongly to remove the rotor, clip may have moved in the same time. In this case upper shaft could have an important axial play.

s class

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Re: 280SE djet ignition distributor shaft axial play
« Reply #4 on: 25 October 2017, 11:24 AM »
Thanks guys, I spotted that clip at the top, it's still in place, my upper and lower shafts are still firmly connected, it's the whole assembly that has end float.  I've ordered some delrin shims from t the local seals manufacturer.   I should. Get them tomorrow.  I've been reading and thinking, seems the swimming belongs between the top of the bushing in the casing and the underside of the trigger points cam

'76 6.9 Euro, '78 6.9 AMG, '80 280SE, '74 350SE, '82 500SEL euro full hydro, '83 500SEL euro full hydro , '81 500SL

s class

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Re: 280SE djet ignition distributor shaft axial play
« Reply #5 on: 27 October 2017, 02:16 AM »
OK, I shimmed between the top of the bushing in the casing and the underside of the trigger points cam.  My end float is now 0.1mm.  Seems all good, I will fit it to the car tomorrow.

'76 6.9 Euro, '78 6.9 AMG, '80 280SE, '74 350SE, '82 500SEL euro full hydro, '83 500SEL euro full hydro , '81 500SL

s class

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Re: 280SE djet ignition distributor shaft axial play
« Reply #6 on: 31 October 2017, 05:19 AM »
OK so I got the car sorted.  It was a bit of a challenge.  I eventually diagnosed and solved the following list of issues :

a) ignition distributor problems as above
b) ignition timing wrong
c) fuel rail pressure was set grossly low
d) ignition coil was dead
e) Djet ECU had a damaged/faulty injection drive circuit, so injectors #2, #4, #6 were continuously open giving maximum fuel
f) MPS end stops had been mucked with.

The combination of all these issues meant it took me nearly 5 hours to get the car running properly. 

'76 6.9 Euro, '78 6.9 AMG, '80 280SE, '74 350SE, '82 500SEL euro full hydro, '83 500SEL euro full hydro , '81 500SL

mrkozzy

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Re: 280SE djet ignition distributor shaft axial play
« Reply #7 on: 04 November 2017, 08:57 PM »
re:  Djet ECU had a damaged/faulty injection drive circuit, so injectors #2, #4, #6 were continuously open giving maximum fuel

I'm curious - How did you diagnose this and what did you do to fix it please?
MrKozzy

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Re: 280SE djet ignition distributor shaft axial play
« Reply #8 on: 06 November 2017, 02:24 AM »
The injectors are fired in two groups of three each.

So the fact that I had issues with three injectors led me to believe its either the ecu, or the trigger points in the distributor, or the wiring.  I first checked the trigger points for operation, since thats quick and easy to do, and they were OK, so then I tried plugging in another ecu, which solved the problem.

'76 6.9 Euro, '78 6.9 AMG, '80 280SE, '74 350SE, '82 500SEL euro full hydro, '83 500SEL euro full hydro , '81 500SL

kepa75

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Re: 280SE djet ignition distributor shaft axial play
« Reply #9 on: 25 June 2019, 07:11 AM »
Hello,

I'm new here and this is my first post. I'm from northern Italy and drive a 280 SE MY 74 since lately.
The car drives well, but stalls a little bit when cold, so now I want to check all regarding ignition.
I realized that my distributor has about 2 mm vertical play.
I don't find any Bosch or Mercedes documents stating that this is to much, but I read here "The ignition distributor has about 2.5mm axial play, spec is ~0.1mm.  "
So, do I really need to shim my distributor? Which shims to be used?
My Bosch shop here has no idea....

Thanks,

Peter