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85 300cd, 2000 ford excursion diesel, 1999 528 itwagon 95 roadking
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371 Posts
Discussion Starter #1
hi everyone been a while since ive had time to log on, here is a problem i am having with my 300, it starts flawlessly, doesn't want to shut off, seems simple but if I apply vacuum to the hose at the injector pump it will shut down,the brakes seem to have boost also I cannot get my climate control to switch , I have fan speed and heat, are these on the same switchover valve?where is this little bugger located this is on a 85cdt California emissions.the killer is this all worked when I did the head and gasket,I cannot seem to find the correct vacuum diagram for the car. any suggestions?thanks in advance,regards, Rousch PS if i am in the wrong area could some one redirect me and the topic to its correct area?
 

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Administratoris Emeritus
2021 SL770
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46,428 Posts
Unless you have a vacuum leak, the issue may be a bad shut-off valve, which attaches to the injection pump. It's a common enough failure.
 

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E320/E250 Bluetec Ford F350 6.7l
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36,729 Posts
Very likely you have the problem all owners of aging cars do. The vacuum tubings deteriorate, loose connections and break apart. Most common on your car is multiple connection in the oil filter area.
The brake seems to be unaffected because it has big hose supply, while rest of the system is goes via 1/8" tubing. Meaning even if you have the 1/8 tubing leaking, the leak will not kill the brake booster. Check the connections manually, than get a vacuum gauge with new couplings and tees. Your car section should already have some DIY tips.
 

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85 300cd, 2000 ford excursion diesel, 1999 528 itwagon 95 roadking
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371 Posts
Discussion Starter #4
thanks for your replies,if I apply vacuum to the vac line it will shut down the engine that's why I was thinking what is between the switch and the shutoff valve, isn't there a switchover valve?is there anywhere on line that has the vacuum diagram for this car all I find is federal,also I have problems with the climate control switching between floor and defrost like no vacuum.where is the switchover valve responsible to transfer vacuum to the shutoff valve? I have the factory cd but doesnt want to work on my laptop running xp. is skinnerbox steaky still active?
 

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E320/E250 Bluetec Ford F350 6.7l
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36,729 Posts
I did restore vacuum system on 87 diesel this summer and had help in the W124 section with diagrams.
What I did was install tee with a gauge close to the pump, than I going "down the Christmas tree" of the tubings -plugging the ends and observing when the vacuum gauge will go up i was finding the branch with the leak. In my case it turned that the transmission tubing had bad coupling plus clima control elements had leaks. The clima elements are controlled by a valve in central console. I think W123 has one in the same location.
From what I remember the switchover valve you are asking about is at the ignition tumbler.
 

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Administratoris Emeritus
2021 SL770
Joined
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46,428 Posts
thanks for your replies,if I apply vacuum to the vac line it will shut down the engine that's why I was thinking what is between the switch and the shutoff valve, isn't there a switchover valve?is there anywhere on line that has the vacuum diagram for this car all I find is federal,also I have problems with the climate control switching between floor and defrost like no vacuum.where is the switchover valve responsible to transfer vacuum to the shutoff valve? I have the factory cd but doesnt want to work on my laptop running xp. is skinnerbox steaky still active?
CD definitely works on Win XP, you may need to uninstall Adobe Acrobat before installing/running, since the manual won't operate with newer versions of Acrobat. AFAIK, skinnerbox is long gone.
 

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85 300cd, 2000 ford excursion diesel, 1999 528 itwagon 95 roadking
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371 Posts
Discussion Starter #7
off the ign switch, there is a metal vaccum tree, is this the shutoff ?does it go from the vac pump to 1 side of the vaccum fitting then when the ign switch is turned off the vaccum dumps to the injector pump?does the metal fitting have a check valve or is there a switch over valve that does this,im confused. thanks for the help,
 

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Administratoris Emeritus
2021 SL770
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46,428 Posts
Yes, that is the shutoff. The line runs to the shutoff valve on the injection pump.
 
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