xjallseasons

Driving home today I blew the upper hose on the radiator off as I overheated. Good thing I was near a convenience mart to fill with water and let it cool down.
Around 2 years ago I replaced the radiator, water pump, hoses, thermostat and coolant. What came out of the overheating was brown mucky coolant. I imagine that water was put into the coolant system and caused the head to rust inside causing the brown water. When I flushed the system last, I ran water thru the system before I completely installed everything back in and noticed nothing dirty. Now its almost like I am back to square one.

djb383

What did u replace the coolant with?.......straight water. The head and block both r cast iron and MUST have adequate corrosion protection at all times.

RTorrez1

When the water is rusty that is called owners neglect. You need to open up the cap once and awhile to make sure everything is right. Don't wait until you have a problem.

xjallseasons

I replaced the old coolant with regular anti-freeze. When I took the older coolant out I saw brown coolant, so I flushed it with the hose and replaced it all with new equipment and "new" anti-freeze. I bought this XJ with 136000 miles 5 years ago and have only put 9000 miles on it since... Its not a daily driver.

xjallseasons

Its really not neglect when I never drive it. I replaced everything with "new" equipment and "new" anti-freeze. Its not that I waited too long to see how my new cooling system was working and its not that I replaced the coolant with water. I have had this xj as not a daily driver and only put 9000 miles on it in 5 years.
So since there was neglect prior to me owning it, how can I fix the problem so this doesnt happen again? I am also considering a 2 or 3 pass radiator when I re-do this again.

md21722

What kind of coolant are you using? Dexcool mixed with conventional green is a recipe for disaster. Distiller water should be mixed 50/50 with pure antifreeze.

Repeated flushing should fix the problem. Look at the overflow container once and a while. It tells more than pulling the rad cap in my experience. Light sediment and rust will show up better by looking in the overflow tank.

You may even need to change the overflow hose. I've seen them filled with rust to the point they can't be cleaned.

bigwheel15

Definitely plan to do multiple flushes. Sometimes a single run just wont get it all clean.

Pelican

What is a 2or 3 pass radiator?

djb383

Don't even think about installing a double/triple pass rad in the XJ......here's why.

http://stewartcomponents.com/index.p...ormation_id=13

djb383

This is a double pass rad. A triple pass makes one additional turn. Inlet/outlet r on the same side/tank of a double pass and on oppisite sides/tanks on a triple pass rad.

https://images.search.yahoo.com/imag...25&fr2=piv-web

djb383

U don't say what kind of coolant u put in. Standard coolant is only good for a year or two and if it's not properly mixed, it won't last that long. As stated, unless u frequently check the coolant by removing the rad cap, the system is neglected. Even standard coolant doesn't turn brown overnight.

xjallseasons

I replaced the coolant with 50/50 Peak. It wasnt full concentrate or long life. I guess I neglected to think that I had a quality or long lasting anti-freeze.

xjallseasons

Thats good info, thanks for the help! Should I have my current radiator flushed professionally or could I save some bucks by doing it myself?

djb383

A good radiator shop will not "flush" a radiator. They remove the 2 rad tanks from the rad core and run a rod thru each tube in the core, thus knocking out/removing any solid scale build-up inside the tubes. Flushing a rad, even with chemicals, will NOT remove any solid scale build-up plugging the tubes. Call a rad shop and get a quote on having the rad "rodded out".

A new OE style single pass rad will run +/-$110 at most local auto parts stores.