June 24, 2018, 05:44:14 PM

Author Topic: Coolant System Level Valve  (Read 2566 times)

Offline Lin

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Coolant System Level Valve
« on: September 30, 2013, 10:04:47 AM »
Given my belief that the bus will demand a certain amount of attention over a period of time and it hasn't required any lately, I decided that I should find something to do on it so it would be less likely to breakdown on the road.  Does that make any sense?

 Well, one thing that hasn't worked since I got it was the valve for checking to see if the coolant level was up.  I'm not sure about whether other MCI's have this, but the 5a has a copper tube coming off the tank about 2/3rds up that goes to a valve with a rod attached to open/close it in the engine bay.  Another tube comes off the valve and also drops down into the engine bay.  Hence, if you open the valve, you can tell it the coolant level is high enough by seeing if any overflows out of the tube. 

My method up until now for checking coolant level was to simply push a 1/4 inch plastic tube down the filler pipe and blow into it.  If I heard bubbles, all was good with the world.  While working on this valve replacement, there was a voice that kept saying, "Now why are you doing this, again?"  But I was able to ignore it and finish the job.
You don't have to believe everything you think.

Offline Ed Hackenbruch

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Re: Coolant System Level Valve
« Reply #1 on: September 30, 2013, 02:08:53 PM »
Mine has never worked either, if feels like it is frozen up. Afraid that if i try to force it it will break.   :(   I have seen that some 5's have a sight glass on the tank, thought about putting one in but haven't gotten around to it. Will be getting a "new" tank in a couple of weeks as soon as we get back to Yuma, from Sam Caylor. Maybe it has the sight glass.   ;D
1968 MCI 5A with 8V71 and Allison MT644 transmission.  Western USA

Offline Red Rider

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Re: Coolant System Level Valve
« Reply #2 on: September 30, 2013, 02:53:03 PM »
ED;

Are you and Stevie going to be at Quartzsite this year? I remember something about being in FL this winter
Mike AKA; Red Rider 4106-1885

Offline Dave5Cs

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Re: Re: Coolant System Level Valve
« Reply #3 on: September 30, 2013, 07:24:59 PM »
Our 5 has the site glass. Makes it real easy to check it.

Dave5Cs from Galaxy S III
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Toed 1998 Jeep TJ

Offline Lin

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Re: Coolant System Level Valve
« Reply #4 on: September 30, 2013, 07:35:32 PM »
This setup is a bit Rube Goldberg, but it does work.  The one advantage it has over the site glass is that you do not need to open the radiator compartment to check the level.  You can check it from the engine bay.  For others, this may not make any difference but as lazy as I can be, it may help.
You don't have to believe everything you think.

Offline Ed Hackenbruch

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Re: Coolant System Level Valve
« Reply #5 on: September 30, 2013, 07:57:58 PM »
Mike, if all goes as planned we will be in Florida from sometime in Nov. to sometime in April. If that doesn't work out then you will probably see us in Quartzsite!
1968 MCI 5A with 8V71 and Allison MT644 transmission.  Western USA

Offline Red Rider

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Re: Coolant System Level Valve
« Reply #6 on: October 01, 2013, 02:45:05 PM »
Thanks Ed,

Safe travels
Mike AKA; Red Rider 4106-1885

Offline Gordie Allen

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Re: Coolant System Level Valve
« Reply #7 on: October 01, 2013, 07:57:10 PM »
On my 4104 I use the finger in the overflow tank filler pipe method.  Insert finger and bend to 90 degree angle.  Finger is wet, coolant is OK.  Finger is dry, coolant needs topping off.  Finger is scalded, coolant is hot.  Best to check before running engine.
Augusta, MI
1956 4104
DD 671