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Coolant hose routing question

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Old Sep 25, 2013 | 01:59 PM
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Default Coolant hose routing question

I have been searching the WSM and have tried searching here and google but I cannot find a diagram of the coolant hoses.

I am trying to find out the routing of the hose from the top of the radiator to the coolant expansion tank. There is a metal T fitting and a line that comes off this line but where does it go to? I found a picture in the WSM that showed them testing the pressure of the coolant system and I saw the T there but I cannot upload a picture from work it appears.

When I took everything apart I'm pretty sure this hose was plugged with a spark plug....
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Old Sep 25, 2013 | 04:45 PM
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Follow the upper radiator hose to the motor. On the backside of where it is clamped you will see a nipple. This is where the 'T' hose connect. At least that is where it goew on my '81.
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Old Sep 25, 2013 | 05:39 PM
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Thank you. I just pulled up a picture of my motor before I did anything to it and you can clearly see a spark plug plugging that hole on the water bridge... *sigh*

emMTI.jpg
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Old Sep 25, 2013 | 10:06 PM
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That's part of the fuel air supply system - no coolant should be in those hoses.

Picture shows the hose (top of photo) where your spark plug appears to be and the white plastic manifold the hose attaches to that I don't see in your photo.

Hose is the one above clamp #25a and plastic manifold is #32.
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Old Sep 26, 2013 | 10:23 AM
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I will have to check again but where my spark plug goes I'm pretty sure there was water when I took it out. Not sure but I will double check. I just know there is a T that comes off the coolant hose from the expansion tank to the radiator and I need to know where that hose goes. I have yet to hook up that part of my vacuum system.
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Old Sep 28, 2013 | 10:28 PM
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Ok I found this diagram that someone posted in my restoration thread. On my water bridge the port it shows this line being connected to is much larger than the hose that is going to it. Something isn't adding up. The line is number 45 in this diagram. Any suggestions?

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Old Sep 28, 2013 | 11:42 PM
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And I just found this picture that shows where it connects and on mine I don't have the part the hose is attached to. It only has the large part just after the hose on the water bridge. Is this something that can be replaced or does it require a new water bridge? Really worried about this part now that I know part of it is missing.

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Old Sep 29, 2013 | 12:21 AM
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Ond of those vent hoses originally had a smaller coolant line passing through the middle IIRC. I don't have an early car so can't give specifics. Just something someone mentioned here.

Anybody?
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Old Sep 29, 2013 | 12:24 AM
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[QUOTE=whatudrivin;10792767]And I just found this picture that shows where it connects and on mine I don't have the part the hose is attached to. It only has the large part just after the hose on the water bridge. Is this something that can be replaced or does it require a new water bridge? Really worried about this part now that I know part of it is missing.

# 45 is correct for 16 valve engine. 32 valve engine that hose comes out the front of the water bridge. This line is the air bleed line to get any air out of the engine side cooling system, it connects to the bleed line from the radiator.
Yours would have had a steel pipe pressed into the rear of the water bridge that the hose connected to. These steel pipes are known to corrode away and it looks like someone has drilled and tapped yours, hence the spark plug for a cork. Simply get a brass nipple [spark plug thread one end and hose barb the other end] screw it in with sealant, push and clamp hose # 45 to it and to the 'T' piece.
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Old Sep 29, 2013 | 09:49 AM
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Based on your first photo above you appear to be missing two components that mount to the water bridge.

The warm up valve (#1) and the Aux air valve (#5).

The two items circled in red in my photo.
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Old Sep 29, 2013 | 10:42 AM
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It does appear that those are missing. Strange. How will the car perform w/o these items installed?

Also the spark plug was not screwed into the hole. There was a piece of tubing clamped to the larger part and then the spark plug inserted into the tube to block it off. I have talked with a local guy that may have a spare water bridge but if he does not I may consider taping it and inserting a brass fitting. Seems much cheaper than getting a new water bridge atm. I assume this line isn't under much pressure and this could be a good fix?
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Old Sep 29, 2013 | 06:27 PM
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Don't think you need a new water bridge. The missing items attach to the water bridge. Car will run without them but you may have issues with cold starts later.
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Old Sep 30, 2013 | 12:00 AM
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Originally Posted by jwillman
Based on your first photo above you appear to be missing two components that mount to the water bridge.

The warm up valve (#1) and the Aux air valve (#5).

The two items circled in red in my photo.
I don't think the L-Jetronic has a warm up regulator of the K-Jet type?
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Old Sep 30, 2013 | 01:58 AM
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Originally Posted by jwillman
Don't think you need a new water bridge. The missing items attach to the water bridge. Car will run without them but you may have issues with cold starts later.
The new watch bridge would be to solve the issue of my missing hose connection point. I have a few possibilities if this guy doesnt pan out with getting another one.
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Old Sep 30, 2013 | 06:53 PM
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Iam not seeing missing fitting on the bridge. There appears to be a hose connected to a fitting on the bridge that now has the spark plug in it.

If I am seeing the right fitting it should connect by a hose to a T fitting (item 47 in the diagram you posted) over by the fender between the reservoir bottle and the jump post for the hose that runs from the top of the coolant bottle along passenger side of the engine copartment to the front of the radiator and over to a nipple on the top of the drivers side of the radiator.

The hose I am talking about is installed inthe firt pisture you posted. Perhaps the T fittig is missing?
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