Cooling system coolant usage

Lin · February 26, 2009, 03:02:32 PM

How much coolant is it reasonable for an 8v71 system to be using over a thousand miles? I think I have put in about 3-4 gallons in about 1500 miles, some of which was in desert summer heat. I have not seen any signs of leaks or water in other fluids.

luvrbus · February 26, 2009, 03:20:14 PM

Lin, I had the same problem with my 5 I put a stop to it by taking the filler cap off and going to a radiator shop and having a regular cap filler made with a 7 lb cap.I am going to do that to my Eagle too.OT here but I have some old Greyhound service records for the 5 I owned if you would like them to show how they were serviced also have 2 of the original sun visors if you like to have them and a power steering pump all for free. good luck

TomC · February 26, 2009, 03:22:41 PM

In a word-NONE! Unless you have a bad radiator cap or a leak in a hose, you should not be loosing any coolant. I would highly recommend you take a sample of your engine oil and have it tested to see if you have coolant in it. Radiator coolant will take out an engine if in the oil. Water in the oil isn't such a big deal since it will evaporate away-which coolant will not do. Good luck, TomC

bobofthenorth · February 26, 2009, 04:42:18 PM

Quote from: Lin on February 26, 2009, 03:02:32 PM
How much coolant is it reasonable for an 8v71 system to be using over a thousand miles? I think I have put in about 3-4 gallons in about 1500 miles, some of which was in desert summer heat. I have not seen any signs of leaks or water in other fluids.

In a word NONE.

http://www.busconversions.com/bbs/index.php?topic=10421.0

Read the whole sorry tale. As far as we can tell it was caused by:
1) operator stupidity
2) an engine that constantly consumed coolant

As Tom advised, get an oil sample done but don't think you are home free if you have clean oil. We had clean oil for 5 years and presumably a cracked head that was burning coolant for 5 years as well.

Lin · February 26, 2009, 05:22:31 PM

Thanks for the info. I have always treated any coolant usage in my cars as a sign something was wrong, but thought it might be different here. Anyway, getting the oil analyzed is not a bad idea. There is only about 1500 miles since the oil change, and I had thought to put more mileage on it first. The oil is a beautiful black, but I suppose small amounts of water would not foam. I still did not find any obvious leaks, and there is a possibility that a good portion of the lose came from not being properly topped off when I removed the OTR heat system. I'll watch things carefully for now.

Clifford,

I have a 4# radiator cap. Is a 7# better, particularly for the desert summer? I have sun visors, but do not know if they are the original type. Is the power steering pump for assist or integral? We are considering a trip to Four Corners for late April/early May and could stop by and see you in Needles then if you expect to be around.

NJT 5573 · February 26, 2009, 09:14:57 PM

Lin,

I can add coolant all the time if I keep it topped off. I have about 22 gallons and topped off cold will always push out up to a gallon from heat expansion. Will it continue to drop or will it find a level and stay there after its been hot?

Put some cardboard under it and let it run for 1/2 hour and look for a wet spot. Put some cardboard a couple feet behind the exhaust on high idle and see if any water is coming out the exhaust pipe.

Check all the hoses to the bus heat/drivers area and the heater/defrost core for a leak. Maybe you just need a tube of Barrs and to turn the water filter off for a while.

jjrbus · February 27, 2009, 02:37:04 AM

On my 5C I was always adding coolant, after a while it seemed like I was adding the same amount. My first attempt at fixing was replacing the rubber hose from the expansion tank to the pipe with a clear hose, to view level. This stopped me from adding coolant in bulk.
After some consulting with Gerald Jenkinson we decided that the gasket on the cooling fill was defective and the pressure relief valve was shot. I bought a radiator neck and modified the fill assembly and had the neck soldered. I removed the pressure valve and replaced it with a pipe plug.
The base of the fill was also slightly warped. This was an easy fix by rubbing the base over sandpaper on a flat hard surface.
No problem since!! hth Jim

luvrbus · February 27, 2009, 03:47:17 AM

Thanks for the photo JIm that is the way I repaired mine with a small reservoir to catch the overflow and return it into the system while it was cooling down Good luck

jjrbus · February 28, 2009, 04:21:50 AM

I did not add a reservoir, with the height the fill and an expansion tank it did not seem necessary, this is on a 5C. Doses your reservoir catch anything?? Jim