Coolant Flush?

eb99603 · October 11, 2016, 10:07:56 AM

I wish I had more time to share my bus adventures with you folks. But for now, you get the condensed version.

Between the end of May and the first part of June I made a round trip from Alaska to Minnesota in my Setra. It wasn't exactly the smoothest of road trips but the old coach made it down and back which is really all I could ask for at this point. On the way back we stayed at the Northern Rockies Lodge in Muncho Lake, BC. Pulled in late at night to a spot I had to back into. I used the neighbors' RVs as depth guides and foolishly didn't have my wife give me a set of eyes back there while I parked. The terrain at the back of the stall made a gradual ascent which was not visible from my seat behind the wheel. The drain valve on the bottom of the radiator scraped along the brush/dirt/rocks/whatever and by morning I'd lost nearly all my coolant.

Next morning, I fired up the coach and let it air up. Drove 20 feet and the stop engine light appeared and shut me down. After finding the open valve, and closing it, I dumped the two gallons of coolant I had with me into the reservoir to no avail. To get back on the road and not be stuck in the middle of nowhere, I opted to fill with water. Whatever water came out of the spigot at the RV park. I left with plenty of extra water knowing full well there were bound to be a good number of air bubbles in the system. Once I called for heat later in the day, air bubbles that were once sealed away were now opened and the reservoir dropped again. By the end of the day, I'd put in something like 17 gallons of water.

So now I'm back in AK and overnight temps are dropping. I don't have insurance right now because Progressive is the only company that insures bus conversions up here and they insist my Setra is either a school bus or a transit bus. Without insurance I can't drive it to a shop. I need to protect my engine over the winter and I can't afford to pay for heated shop space. No one will come out and do a coolant flush for me. So, here are my questions for you more experienced readers out there.

1) Can I just drain a few gallons of what's in there now and add a few gallons of concentrate? Then drain the mixture into a sample cup and throw it into my freezer to make sure I have enough protection?
2) Is that mystery water and it's unknown mineral content going to do harm to my engine? Should I do a wholesale flush?
3) Is this as simple as bleed out the bottom of the radiator and fill into the reservoir? How's one get all of the air bubbles out, or the coolant in the HVAC system purged too?

Thoughts? Thanks in advance.

(And for whatever it's worth, the coolant in there is red. No idea what brand/style.)

Iceni John · October 11, 2016, 10:30:25 AM

Quote from: eb99603 on October 11, 2016, 10:07:56 AM
1) Can I just drain a few gallons of what's in there now and add a few gallons of concentrate? Then drain the mixture into a sample cup and throw it into my freezer to make sure I have enough protection?
2) Is that mystery water and it's unknown mineral content going to do harm to my engine? Should I do a wholesale flush?

Coolant test strips will tell you if your glycol concentration is OK, and will also test nitrites and pH. Well worth it. I use NAPA strips, but there's plenty of others.

I suggest draining out the tap water and using either distilled water (even though it's slightly acidic) or RO water. The minerals in tap water are not good for cooling systems, but for a short while it should be OK until you can change it.

At least you now know your Low Coolant Level shutdown works! I made a coolant level gauge for my surge tank so I can easily check coolant level every time I start.

John

Iceni John · October 11, 2016, 10:45:43 AM

One more thing you may want to do when you have time. I recently changed my radiator's drain valve from the original teeny-tiny bleeder valve (it took half an hour to drain!) to a 1/2" brass faucet with a thread-on brass cap over its garden hose thread outlet, but I made sure it's not the lowest point under the radiator, and I ziptied my new valve's turn handle so it cannot inadvertently open or be easily opened by some prankster.

John

eagle19952 · October 11, 2016, 11:01:16 AM

you could use one of these

eb99603 · October 11, 2016, 11:10:15 AM

Never seen such a thing. Feel like a dolt for not looking for something like that first.

eagle19952 · October 11, 2016, 11:34:19 AM

Quote from: eb99603 on October 11, 2016, 11:10:15 AM
Never seen such a thing. Feel like a dolt for not looking for something like that first.

sorry, that was not my intent. just trying to help.

eb99603 · October 11, 2016, 11:53:05 AM

No offense taken! On the contrary; I appreciate the info!

luvrbus · October 11, 2016, 03:48:38 PM

Being red in color you probably had the Detroit Power Cool antifreeze,is your engine a 60 series ? if so the series 60 is not as forgiving as the old Detroit 2 stroke when it comes to water and antifreeze they need to be right or you pay a heavy toll

brmax · October 11, 2016, 04:47:49 PM

As the weather is still good, possibly best choice is just drive it to a truck service location, if your in a location that has a service center. I'm not familiar with any field/road service mechanics available up there, but someone here I'm sure does.
good day
Floyd

Scott & Heather · October 11, 2016, 05:43:17 PM

I am not one for risking my radiators, heater core, or engine with a coolant mix that isn't freezeproof especially when you're talking Alaskan winter temps. It cost me a pretty penny to have a split heater core tube repaired this summer. Drain and add straight concentrated coolant and run it in the coach so it mixes well and test it with test strips.

Sent from my iPhone using Tapatalk

eb99603 · October 11, 2016, 08:30:16 PM

Bought one of these: https://www.amazon.com/Prestone-AF-1420-Antifreeze-Coolant-Tester/dp/B000BOA9RY Told me I'm at +10 deg with the mix that's in there now. I'll grab 9-10 gallons of concentrate, and give the drain/fill strategy a whirl while running the coach heat on full bore.

Floyd - would love to, but I don't have insurance so I can't drive it.

Luvrbus - PowerCool or one of the complaint alternatives. I think Fleet Charge or Final Charge might have been the brand used last time. And how heavy of a toll are we talking? Are you saying I should flush everything that's in there now due to the (potable but not distilled) water that was put in?

Cheers.

luvrbus · October 11, 2016, 09:08:18 PM

I see now it is a 60 series

I would start over the pre charged antifreeze's don't do good with potable water,R/O water works for me. Could be since you are not driving it freeze protection should work. 5 more gals and you won't loose the 10 gals you plan on pouring in when driving time comes again

B_K · October 11, 2016, 09:19:50 PM

That model Setra holds 22 gallons when you drain the radiator and refill it!
I have owned 7 of them and have drained and refilled the radiators plenty of times.
(FWIW the S417's hold 55 gallons due to "chiller station for the A/C system!)

So if it were me I'd rain it and refill it using 11 gallons of straight anti-freeze and the rest RO water and also use the test strips to be sure it's good on the additives.
When was the coolant filter on the engine replaced last?

BK

daddysgirl · October 12, 2016, 09:12:45 AM

If it were I...in those temps especially, I would flush it, look for mineral deposits and refill it with the red stuff.
One of these days, I'm going to have a few system heaters for the engine bay

eb99603 · October 12, 2016, 01:55:59 PM

BK, are you saying the entire cooling system capacity is 22 gallons? Or that's what's in the radiator, reservoir, and engine compartment hoses? If I just drain the radiator and refill, won't I only be flushing a portion of the total coolant? How does one go about effectively flushing everything running up/down the length of the coach to the various heater cores?