Author Topic: 230sl M127engine without idling  (Read 6357 times)

Benz Dr.

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Re: 230sl M127engine without idling
« Reply #25 on: December 18, 2018, 18:52:26 »
HI ja17. I have tried disconnecting the engine linkage at the intake butterfly as the engine warms. Within 3 minutes of warming-up, the CO from 7.5% drops to 1.9%, and when it begins to stall, and I open the intake venturi lever slightly, but it doesnt help, the engine died anyway.

What should we do next?

Thanks for your help.

Regards,
Danny
[/quote

Disconnect your linkage going down to the IP from the cross shaft so that the throttle valve will open when you move the linkage. Disconnecting at the venturi will give you nothing in terms of results.
1966 230SL 5 speed, LSD, header pipes, 300SE distributor, ported, polished and balanced, AKA  ''The Red Rocket ''
Dan Caron's SL Barn

1970  3.5 Coupe
1961  190SL
1985   300CD  Turbo Coupe
1981  300SD
2013  GMC  Sierra
1965  230SL
1967 250SL
1970 280SL
1988 560SEC

ja17

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Re: 230sl M127engine without idling
« Reply #26 on: December 19, 2018, 04:18:24 »
The oval shims come in many thicknesses. They are used to set the fuel mixture during warm-up period only. After warm-up the WRD has little or no effect on mixture. Less oval shim thickness, leans the fuel mixture during warm up. For cold starting problems, check your starting aids first.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

dnadanny1

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Re: 230sl M127engine without idling
« Reply #27 on: December 19, 2018, 07:28:16 »
Thanks for your sharing. the fuel filter is good and clean, and it is newly replaced a couple years ago.

dnadanny1

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Re: 230sl M127engine without idling
« Reply #28 on: December 19, 2018, 07:44:46 »
Have you verified your point gap and ignition timing are spot on?
Just saying.

I have changed to 123 electronic ignition, therefore there is no point gap.
For ignition timing, it is BTDC 4-6 @ idle.

Thanks a lot.

Regards,
Danny

dnadanny1

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Re: 230sl M127engine without idling
« Reply #29 on: December 19, 2018, 09:51:19 »
For the split linkage test, if I cant get my car to idle when it is warmed, how should I continue with the test?
However, when there is fast idle, I can keep it away from stalling by pushing down the linkage to the IP.

Thanks a lot.

Regards,
Danny

Tom in seattle

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Re: 230sl M127engine without idling
« Reply #30 on: December 20, 2018, 00:38:21 »
The Oval shims:  do you mean the the one with a large hole in the middle, large enough to accommodate the entire piston unit, and with two holes to accommodate the entire upper section being bolted to the lower part of the WR?.  Or am I looking for something down under the piston unit inside the body of the WRD.  I find nothing in there down low.  I thought the item describe above were  a gasket. Mine only had one.

Thanks for the input.
Tom Averill
1967 250 SL Auto Euro Spec

Tom in seattle

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Re: 230sl M127engine without idling
« Reply #31 on: January 07, 2019, 23:25:11 »
Its me again, thanks for your patience.  I have cut some shims out Of a plastic lid.  They are each about 2/1000 thick.  I started by placing 2 under the collar that sits above the FI body. This has the effect of raising the entire water chamber and pin system up about 4/1000 ".  With the engine cold (about 50' F) I attempted starting and after the 3rd try it fired and stumbled, running about 400 rpm then died. It did not go into a fast idle.  There have been no shims used prior.

So my question at this point is :  how much shim thickness should I be using or at least to begin to see a measurable difference?  I'm still not getting a measurable fuel enrichment.

I'm just trying to get the engine to start as designed to do so.  I have wired in a momentary switch under my dash which supersedes the ignition switch activation of the fuel valve attached to the intake plenum.  I can easily start the car by engaging the switch if the engine starts to stumble.  It takes a couple minutes of thus coaching and it then begins to idle properly and it runs great thereafter.
Tom Averill
1967 250 SL Auto Euro Spec

mrfatboy

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Re: 230sl M127engine without idling
« Reply #32 on: January 08, 2019, 00:20:32 »
Tom,

I think you are talking about adding oval shims under the WRD as you described in your earlier post. Adding shims will enrich your mixture during WARM UP only.

Usually there are 3 shims under the WRD of different sizes. Over the years I'm sure people have added or removed. Typical sizes of these shims are

.12mm
.63mm
.5mm
.2mm
.1mm

Different combinations of the shims are used to get your desired thickness.  I think my 3 shims add up to around 1.2mm (if I remember correctly :) ) so I would think somewhere between 0mm and 1.2mm to start.

I would also suggest using thin metal to make your shims and trace them from the WRD housing if you don't have an existing shim.  You can get the metal sheets from local hardware store.  For example, get a .2mm sheet of metal and make 6 x .2mm shims.  Maybe try 3 of them at .6mm total to start with and play with it from there.
1969 280sl (Aug 1968 build)
Signal Red
4 Speed

ja17

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Re: 230sl M127engine without idling
« Reply #33 on: January 08, 2019, 01:10:49 »
Seems like you may  be running lean? Make sure you have at least 12-16 psi of fuel pressure. Simulate more shim thickness by leaving the two screws holding the WRD to the IP loose and simulate shim thickness by turning the screws.  Make sure your ignition timing good.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback