I have a 102A3.
My coolant recovery pump has stopped working, and adding coolant to the surge tank is near impossible since the cap for it is not only up high, but higher than the access door.
Anyways, it's time to replace it.
The one in my bus is a ShurFlo 2088-574-534.
My bus seems to hate ShurFlo and FloJet pumps, I use to use them for water and they'd die every year.
Evidently it's a 3.6GPM pump with a 45psi demand switch (though I'm not sure why it'd need that since it is automatically operated by the bus).
Instead of buying a (not so) ShurFlo pump and spending hundreds of dollars, I'm noticing that there's plenty of solar water pumps that are 24V and can handle hot water for *much* cheaper on ebay.
Has anyone tried a different pump for the coolant recovery tank? And is a ShurFlo even what the bus started with? Any ideas on what stats I need to concern myself with?
There's a part of me that thinks that even a much slower pump would work because returning coolant from the recovery tank to the surge tank is uncommon and doesn't need to happen in a rush.
I just noticed in the parts manual that the pump listed there is 40 psi, but it doesn't give any other info on the pump.
Anyone know what the requirement are for this pump?
And also, what is the route for coolant going up to the surge tank, on my bus it doesn't seem to go up to the surge tank, is it just pumping coolant directly into the coolant lines down by the engine in order to fill up the top tank?
Someone elaborate on this? I've never heard of a coolant pump for the surge tank. I just thought heat and pressure expanded the coolant and pushed it into the surge tank thermally and when things cooled down it sucked it back into the cooling system??? Is this some sort of other coolant circulation system for something else?
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I thought all buses had the small coolant pump installed.
The purpose of the pump was to take the water from the back of the bus to the drivers heater at the front 35 to 40 ft away.
I have repurposed those pumps ie: to replace the Webasto circulator pump that is way over priced.
I currently have two original pumps installed and working fine for that purpose, it keeps the expansion take tank full.
My 102C3 has a recovery tank that is below the AC compressor. Coolant is pumped from there into the tank that is above the cooling system. I had to replace the pump and used a Sureflow.
Jack
On a related note, a friend's new to them 102C3 has the pump, it runs, but it won't move any coolant.
Lines maybe plugged?
MCI put this system in in order to add coolant. The surge tank is up behind the rear roof cap in the C and D, the "filler cap" is impractical without using a supply hose under pressure, and an awkward stance at the top of a ladder. The flat rectangular tank is mounted under the AC compressor, with the familiar "filler cap" on it, the electric pump is mounted just above, behind the tail lights, and is supposed to send the coolant you put in the lower tank, up to the surge tank. The toggle switch is mounted on the rear engine control box. There is a sight glass way up there on the surge tank to know you are done.
Nice system, (when it works) everything happens at ground level, much safer...
happy coaching!
buswarrior
Exactly as buswarrior describes, except I haven't seen a sight glass on my surge tank (nor do I know how I can view the top of the surge tank while down by the switches), the only way I know to fill it is to run the pump until it starts to leak.
Evidently the bus is also supposed to automatically run the pump when the surge tank gets low, don't know if that's happening on mine since so many of the indicator lights aren't working.
My 102a2 just has a sight glass. I found after I fixed all the small leaks and a new waterpump. I don't have to get my folding platform out to re fill it anymore. I would think that if it goes down so far but no further after filling that maybe your just overfilling the system thus it always overflowing. My sight glass is right in the center of my expansion tank. Usually my wife looks while I fill.
Interesting. Neither my 9 nor my 102C3 have this pump setup. Just a normal surge tank sitting above the squirrel cage radiator blowers.
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Perhaps you can make out the image below, I believe this will help. It is the water pump for the coolant recovery system. I too had issues with this but did not have the time to really check everything out... I had to get coolant in the system and get back on the road. I used a siphon hand pump to get the coolant in the surge tank. It was a PAIN and a messy job. The coolant recovery tank was definitely full, coolant would come out when I lifted the fill cap. I think the pump is likely not working on my bus as well and would like to get in there and fix it. You are supposed to fill the coolant through the recovery tank but it doesn't help if that is disconnected from your coolant system via faulty pump! Any insight on how to diagnose and specs to replace would be great. I will probably take a closer look at that this weekend and see if I can maybe pull the part. Anyhow, hope this helps someone.
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi277.photobucket.com%2Falbums%2Fkk53%2Fthebear_09%2FScreen%2520Shot%25202016-03-09%2520at%25208.59.22%2520PM.png&hash=b4b810e192518a8afcf2357c0c188e3ea64aa46f) (http://s277.photobucket.com/user/thebear_09/media/Screen%20Shot%202016-03-09%20at%208.59.22%20PM.png.html)
My operators manual says the fill tank is inside the right hand engine compartment door. Says turn the battery switch on and the light should come on. If not test light. Fill tank then hold pump switch on open vent on cross over tube. Refill tank when pump stops until system is full. Close vent when coolant pours out. Light Turns off when system is full. Light and switch are on the remote box. To test the pump. Use a test light and see if it gets power when you turn the switch on.
I'm so intrigued. Never knew some buses came with this. As I mentioned, I don't have this on either of my buses. I just have a fill door and cap up high on the curb side above engine. Goes to the surge tank and that's it.
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Scott -
I kind of wish all I had was a fill cap! Though the recovery tank is meant to be helpful it is one extra thing that can break... and when it does it is a mighty big hinderance!
This pump came out with the "flat back" C model, aprox '92. The early C models were set up like the 9's with the flap on the side, when they went to the flat back the upper tank was relocated. Interestingly most of the flat back buses that I have been around, including 30+ in our fleet just have a pump similar to a 12 volt "house" rv water pump, however my personal DL3 motorhome does have an "auto" refill. I don't like that at all and need to rewire it so that it only works with the switch. Any domestic rv water pump will work, if I remember correctly the originals were 24 volt, but we convert most of our fleet to 12 volt to buy cheaper pumps.
Why are you not a fan of the auto refill? Seems like a nice feature.
And did you rewire the entire system to 12V, or just the coolant pump? And if so, are you running 12V from the battery bank all the way to the back of the bus just for this pump?
Interesting Adam. Our 102C3 of course now has Renaissance caps so it's now a "flat back" with a normal radiator fill cap up top to the side. Cool. (https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fuploads.tapatalk-cdn.com%2F20160311%2Ff8c7b4325b0932c088839ae6547f1251.jpg&hash=3034f4becafdd375a30af4196985bfd7ad7601bf)
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Quote from: daveola on March 11, 2016, 12:29:44 AM
Why are you not a fan of the auto refill? Seems like a nice feature.
And did you rewire the entire system to 12V, or just the coolant pump? And if so, are you running 12V from the battery bank all the way to the back of the bus just for this pump?
It is one more thing that can break... and when it does there is not an easy way to refill the cooling system so you have to go through the timely and potentially costly repair procedure before using it again. I would rather just have a fill cap that is easily accessible and be done with it!
But here is an idea. How about splicing one of the lines that lead from the surge tank in order to install a fill cap should you be in a position that the recovery system does not work but you need to top off the system? The main issue is knowing when it is full and/or not putting air in the system. You can easily install a "sight" by having one small section with clear tubing towards the top but you open yourself to a location of potential leaks.
Just a thought, I will ponder some more.
These systems arrive failed because the coach has been in the hands of paid help who did not care, chose to not understand, thought it was funny to just switch it on and leave it run dry until it burned out, put some less skilled person to try to fix it, made it worse, gave up, sold coach....
Once it has been put right by the busnut, who has a vested interest in using it correctly, it will do the job as it was engineered to do, safely at ground level.
Every old guy I know who fell off a ladder, wishes he hadn't. Reduce your exposure!
The access door you would need to cut to do it manually will be right up at the clearance lights, centre back, get your taller ladder, your multiple pails of coolant, a funnel that will work horizontally while you try to pour... and cut it, brace the hole, install a hinge, a method of closure...
The stock system is simple. A lower tank, a common DC water pump, some coolant lines, a switch and some wire.
happy coaching!
buswarrior
That makes sense... I just need to locate and replace the pump now!
Some MC-9's, maybe most, have a 12v source on stud 41 in the rear junction box. The pump injects the coolant directly into the coolant return plumbing from the radiators to the water pump through a remote check valve. Since it is supplied from the reservoir which is completely separated from the working cooling system with check valves, the pump will normally not see engine-temperature coolant at any time, just ambient temperature (unless it gets some coolant pushed down to it past the 7psi check valve on the line to the header tank). The schrader valve that comes down from the middle of the header tank is the level check device, you could add a bit of clear tube and make a visual sight gauge there if you wanted to. Neat system, I wonder how they automated it.
Edit: this forum is a dangerous place! Now I am thinking "why not build a mount for a 5 gallon pail of oil where the ac compressor used to be with a little electric pump and tap into the oil pan so you can fill your engine with oil by flipping a switch instead of getting out a hand pump, a funnel, a little table to put the oil pail on, and cleaning up all the oil that spills when the funnel slips"
My Prevost has a remote oil tank just for that. Gravity fill from the resevoir to a ball valve at the block, easy top ups.
Ryan.
For something like that I would just make it work with a jump box. I have a 50 foot extention cord. I put alligator clamps on one end and a heavy duty power port on the other. Comes in handy.
The system of a lower tank and a pump to refill to the top is a good idea, and is much easier in commercial service then having a driver in a clean white shirt and tie standing on a ladder in the parking lot at 3 am trying to poor coolant above his head. However I don't like the "auto" refill system for 2 reasons: it always refills when the coolant starts to cool, which always happens about 4 am after running all day, and it wakes me up and every time I wonder what that noise is for about 10 seconds. The other reason is if the lower tanks is not full the pump could run until it damages something (the pump). I also want to know if the coolant level is going down, which I would not know if it pumps automatically. I'm happy getting 12 volt power in the rear J box, and installing a cheap water pump.