Author Topic: Bad hot idle and starting .Fresh air filter  (Read 3213 times)

91lux

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Bad hot idle and starting .Fresh air filter
« on: August 26, 2006, 14:05:44 »
Hi
Just wanted to share what caused my engine to stall and had a bad idle when warm.
It started easly but could not run at idle when warm.
The fresh air filter and the airhose attached to the injection pump were interchanged.Previous owner or workshop had them put in the wrong place so they traded places. The filter was cut of when heated up and the air hose from intake would stay open.
This fault is easy overlooked even by a Bosch work shop i contacted to check out the bad idle .They gave up. Finaly I found out myself after a year of trying everything. Now everything is working perfect.

BR 91lux

Naj ✝︎

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Re: Bad hot idle and starting .Fresh air filter
« Reply #1 on: August 26, 2006, 14:42:16 »
Good result [:p]

naj

68 280SL
68 280SL

hands_aus

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Re: Bad hot idle and starting .Fresh air filter
« Reply #2 on: August 28, 2006, 13:22:50 »
The car should not have idled at all with the original configuration.

Have you tested the WRD to make sure it cuts off all air when at working temp?



Bob Smith (Brisbane,Australia)
RHD,1967 early 250 SL, auto
Bob Smith (Brisbane,Australia)
RHD,1967 early 250 SL #114, auto, ps , 717,717
best of the best

91lux

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Re: Bad hot idle and starting .Fresh air filter
« Reply #3 on: August 29, 2006, 00:07:33 »
Hi Bob,Brisbane (Australia is lovly as i visited in 2000).

You are probably right. It was differcult to make it idle when hot,so i had to adjust it with the flap.!! No good of course.

The WRD is working as intented,but with the setting were the fresh air filter and the air supply hose were interchanged i had to adjust the air intake flap to make it run at warm idle  .This is of course not recommended as the flap shall be totally closed when idle.

It also affected the oil level in the pump as i think (but can not be sure) that the misplaced extra air hose created underpressure in the pump as it is connected to the intake manifold, this because that the WRD shuts of the air hose connector but probably leaves the fresh air filter open.
The oil level was increasing at a quick rate i had to suck out  maybe a half a litre every 100 km. That concerned my so much if that  something was wrong with the inj. pump.I visited a Bosch dealer but they found nothing.

Anyhow this all sorted out when the hose and the filter was put back to the correct spot. Smooth and robust idle and no significant change in oil level at the inj. pump.

Regards 91lux

hands_aus

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Re: Bad hot idle and starting .Fresh air filter
« Reply #4 on: August 29, 2006, 05:58:33 »
91lux,

I am glad you sorted the problem.

Australia is a beautiful country of many different colours.


Bob Smith (Brisbane,Australia)
RHD,1967 early 250 SL, auto
Bob Smith (Brisbane,Australia)
RHD,1967 early 250 SL #114, auto, ps , 717,717
best of the best