thermal vacuum switches
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I've found two in my 87 XJ-S 5.3L V12, one on the fuel rail, and another on the RH rear cooling manifold.
The one that came off the fuel rail (on the right side of the photo) is missing it's "cap", and thus its part number. Testing it, I find that it activates at 90 degrees C, 195 degrees F.
The other one that's off the cooling manifold, shows part number EAC4083. This gets somewhat confusing, since the reference I'm looking at says "from (V) 179737" (mine is 134879) but the intro page says the part #'s should be good for my VIN and engine number.
I suppose the above isn't as important as if the things are working right. I've not found documentation on what temperature each is supposed to activate at...are mine close?
Finally, what is the one on the coolant manifold supposed to do? I've seen a few pics of different cars with the switch there, but the vacuum lines no longer attached.
Thanks,
John
1987 XJ-S V12, 62,000 miles
The one that came off the fuel rail (on the right side of the photo) is missing it's "cap", and thus its part number. Testing it, I find that it activates at 90 degrees C, 195 degrees F.
The other one that's off the cooling manifold, shows part number EAC4083. This gets somewhat confusing, since the reference I'm looking at says "from (V) 179737" (mine is 134879) but the intro page says the part #'s should be good for my VIN and engine number.
I suppose the above isn't as important as if the things are working right. I've not found documentation on what temperature each is supposed to activate at...are mine close?
Finally, what is the one on the coolant manifold supposed to do? I've seen a few pics of different cars with the switch there, but the vacuum lines no longer attached.
Thanks,
John
1987 XJ-S V12, 62,000 miles
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I think it opens the air injection divertor valve. Can't quite remember.
Go to the "How To" thread at the top of this section and then to "Downloads". Look for the "S58" manual. The operation of the switch might be explained in that manual. (Good reading even if the operation of that switch isn't mentioned)
Cheers
DD
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Thanks for the replies.
I wish the fuel line switch didn't have the end broken off of it. I see that they are NOT cheap ($100 + or so), and I'm scratching my head trying to figure out how to fix it. My experience with JB Weld is that it doesn't seem to like (as in adhere to) plastic very much.
Thanks,
John
I wish the fuel line switch didn't have the end broken off of it. I see that they are NOT cheap ($100 + or so), and I'm scratching my head trying to figure out how to fix it. My experience with JB Weld is that it doesn't seem to like (as in adhere to) plastic very much.
Thanks,
John
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Well darn, she vapor-locked on me this evening.
No big deal. Ironically, I was at the auto parts store looking for another lug nut (which I didn't find), went out to go home and no-start. Popped the bonnet, waited 15 minutes, started just fine.
I still don't want to spend the $100 :-)...and I wouldn't have to if there was a glue/epoxy that would stick to hose material and whatever plastic the thermal valve is made of.
Just had a (brilliant) thought...what if I just switch the thermal valves? Since there is no air pump on mine, and thus the valve is serving only to plug the hole in the water manifold, any reason to expect bad things would happen if I use it on the fuel rail?
Thanks!
John
1987 XJ-S V12, 62,000 miles
No big deal. Ironically, I was at the auto parts store looking for another lug nut (which I didn't find), went out to go home and no-start. Popped the bonnet, waited 15 minutes, started just fine.
I still don't want to spend the $100 :-)...and I wouldn't have to if there was a glue/epoxy that would stick to hose material and whatever plastic the thermal valve is made of.
Just had a (brilliant) thought...what if I just switch the thermal valves? Since there is no air pump on mine, and thus the valve is serving only to plug the hole in the water manifold, any reason to expect bad things would happen if I use it on the fuel rail?
Thanks!
John
1987 XJ-S V12, 62,000 miles
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