Vacuum tube 1988 230 GES
Looking at the engine from the front at the top just behind the thermostat housing and below the plug leads are two vacuum tubes.
One goes to the exhaust manifold where does the other one go and what does it do??
Thanks in anticipation
If it is what I am thinking of, it is a thermo valve opening at 50 degrees and allows to operate the EGR (Exhaust Gas Recirculating) valve which helps recirculate a small sample of exhaust gases back into the inlet manifold. This helps reduce emission levels.
One end attaches to the EGR valve mounted on the exhaust manifold and the other attaches to the throttle body.
Hi John
Item 26 in the picture, the big man is correct as per usual
Gav
Rakesh and Gav many thanks.
Exhaust manifold vacuum pipe is long gone and manifold end blanked off .
Is there any need to replace parts 32 to 26 on the diagram ? If not should I block off both ends to stop any vacuum leaks to the inlet manifold? Tickover seems just a shade high (900 rpm compared with 750 rpm) since the pipe was lost.
John
If the German Austrian Dude put it there, it does something!!!! Better with it on than off!!!
PM me your home address and i will post you some, i have metre's of the damn pipe in my garage!!
26 - 460mm of A000 158 88 35 Pipe
29 - 40mm of A117 997 09 82 Hose
32 - 1 of A117 078 05 81 Elbow (or another 40mm of above)
Can send you the Pipe and Hose, might even find you an Elbow if your lucky
Let me know
Gav
No harm in them being disconnected, just plug up the throttle body side - a screw in hose 29. This will stop your false air leak into the inlet manifold and may reduce your idle speed. Your emission may need to be checked and accordingly readjusted.
If the idle needs resetting; I think, there is an idle adjuster screw. I'll check and come back on that.
What is your engine M115 or M102?
No harm in them being disconnected, just plug up the throttle body side - a screw in hose 29. This will stop your false air leak into the inlet manifold and may reduce your idle speed. Your emission may need to be checked and accordingly readjusted.
If the idle needs resetting; I think, there is an idle adjuster screw. I'll check and come back on that.
What is your engine M115 or M102?
M102...
If the idle needs resetting; I think, there is an idle adjuster screw. I'll check and come back on that.
Idle speed screw:
Photo shows how to find it on the cars - will be same place on the G, but obviously without the air cleaner being there.
Idle mixture is the usual allen key on the fuel distributor. But you need to know what you're doing with that. If not, get someone who knows and understands the system to do that part. Takes all of 5 minutes to tune the mixture by ear.
.......................................... Takes all of 5 minutes to tune the mixture by ear.
Beg to differ mercfan, perhaps my hearing is poor; I have tried setting mixture by ear on fuel injected engines and in my opinion it is not even close and would comment it is not possible. Carburetted engines' however, is possible to set by ear.
Reiterating on mercfan's picture showing the idle adjusting screw; the screw is correct but this picture is off a saloon whereby the air filter housing is different. That being the case, the idle adjuster is located as shown.
Below is another illustration showing the same - refer to screw itemised number 14.
No harm in them being disconnected, just plug up the throttle body side - a screw in hose 29. This will stop your false air leak into the inlet manifold and may reduce your idle speed. Your emission may need to be checked and accordingly readjusted.
If the idle needs resetting; I think, there is an idle adjuster screw. I'll check and come back on that.
What is your engine M115 or M102?
M102...
I thought of sharing something recently learned. I had known that, the 230 G-Wagens' had two engines. M115 and M102 but only recently discovered that it is the 230G which is with M115 engine and 230GE which is with the M102 engine. To those in the know, the 'E' insignia indicates Fuel Injected engines; from that it is logical to see that the M115 engine is carburetted only and not fuel injected. It is that element I had not known.
To those clever dicks who come and claim "I knew that...." Yeah, sure.you did - Book worms'.
No harm in them being disconnected, just plug up the throttle body side - a screw in hose 29. This will stop your false air leak into the inlet manifold and may reduce your idle speed. Your emission may need to be checked and accordingly readjusted.
If the idle needs resetting; I think, there is an idle adjuster screw. I'll check and come back on that.
What is your engine M115 or M102?
M102...
I thought of sharing something recently learned. I had known that, the 230 G-Wagens' had two engines. M115 and M102 but only recently discovered that it is the 230G which is with M115 engine and 230GE which is with the M102 engine. To those in the know, the 'E' insignia indicates Fuel Injected engines; from that it is logical to see that the M115 engine is carburetted only and not fuel injected. It is that element I had not known.
To those clever dicks who come and claim "I knew that...." Yeah, sure.you did - Book worms'.
The two engines also look very different. The M115 has a fairly narrow and high cam cover unpainted in plain alloy. Looks much like the 616/617 series cam cover. Basic, clean simple old skool engine with carb, distributor, points and condenser, which is much easier to work on than the later ones. Very sought after nowadays as period correct replacement in for example W115 cars. Notice the number correspondence? Always wondered if that was intentional back then?
I have tried setting mixture by ear on fuel injected engines and in my opinion it is not even close and would comment it is not possible.
Idle speed to around 700, then mixture until you get highest revs (very lean, some surging), then a tad back until engine sounds sweet. Go slightly on the lean side if you're doing it with the air cleaner off. Give engine a few revs after every adjustment to clear any residual previous mixture. Remember small adjustments make a big difference. Re-adjust idle speed screw to correct idle speed if required. Will be spot on correct. You get the hang of it after you've done it so many times. Same for all M102/103/116/117 with K jetronic.
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Rakesh and Gav many thanks.
Exhaust manifold vacuum pipe is long gone and manifold end blanked off .
Is there any need to replace parts 32 to 26 on the diagram ? If not should I block off both ends to stop any vacuum leaks to the inlet manifold? Tickover seems just a shade high (900 rpm compared with 750 rpm) since the pipe was lost.