All - I just need a sanity check here for my 2004 Disco 4.6 w/ SAI, 146K miles.

For about the last year or so I've been loosing coolant very, very slowly no huge deal. I did have a small bout with the motor getting up to 215 degrees at a stoplight then cooling back down to around 200 under speed (I have a ScanGauge plugged in) - but I replaced the thermostat and fan (viscous clutch) and everything seemed fine - it would stay around 200-211 range .

Then all of a sudden, about 3 months ago when the weather started getting cooler, I started loosing coolant more rapidly. My truck stood still for a week while I was gone on Christmas vacation, and arriving home there was no coolant in the tank and everything seemed "misty" under the hood.

Just for the hell of it, I replaced the water pump (heard some chirping earlier) and also noticed a leak in the hose going from the throttle body heater to the intake - it was leaking where it goes into the intake. I replaced that hose, but put the old clamp back on (no idea what you call this - not the screw-type). After putting all back together and letting sit overnight, I filled with Amsoil coolant using the methods presented here (https://landroverforums.com/forum/di...tem-dii-23072/) however during the process the tank started to overflow. I capped the tank and let cool down, filling again and bleeding through the hose as the manual suggests this time.

So, the Rover was still running a little warmer than I'm comfortable with - reaching 215-220 at stop lights but getting down to 194 when I'm going 70mph in the cool GA morning hours. Looking at the engine this weekend, I notice that I still have a leak at the hose on top of the IM (should have put the screw-type clamp on), that I had a small leak in the hose hooked on the water pump, and there was water stain (not really much - yellow from yellow coolant) running down the rear passenger side of the motor - like down the bell housing. Also, I didn't get all of the Dexron coolant out, as my Amsoil yellow coolant is now yellow-orange.

So now I fixed the water pump hose, sort of (clamp was positioned wrong, positioned it right and it leaked more, put a screw-clamp on it stopped leaking but the other end of hose started leaking slowly). Now even in the morning I'm hitting 220 easy at stop lights but it cools back down under movement. The only coolant leak making it to the pavement is from the one side of the hose. Still not sure if the stain running down the back is coming from the leak in the hose on the IM.

Now the questions ... given the small leaks, is this leading to the higher temps? I'm wondering if I also have a small external head gasket leak, or a valley pan gasket leak that I can't see that's contributing to this and the higher heat. Absolutely no signs of internal head gasket leaks (oil is normal, no sweet smell in exhaust, no lack of power, no dash lights, etc.)

I realize I probably need to get this to the shop to figure this out, but was wondering if you all had any suggestions. (as always, trying to be cheap)

 

Always worry that chirp is from the front propshaft that needs grease fittings...

You can figure this out at home, just borrow coolant pressure tester from parts store and pump up to 18 PSI or so. The cap vents at 20 PSI. You'll find the leaks within 30 minutes or so. Attached is a flow chart of coolant paths from the RAVE. Lots of places to check.

The loss of coolant would be contributing to the increased heat, no matter the source of the leak. If you used an after market thermostat that could be an issue. There are also small metering holes in the top leg of the stat, if clogged they change the temperature it operates at. All the flushing may have clogged those holes.

Pix of dexcool sludge, which reduces cooling of radiator; thermostat metering holes (no place for sludge); flow drawing attached.

 

Broke, PM me your number and I'll walk you thru what to do and check.

 

Coolant out = air in... air pockets might be causing the sudden increase in temps, or perhaps you have a clog somewhere thats puting more pressure in the system causing the hose leaks? new waterpump would probably be putting out more pressure then the one you replaced especially if it were particularly worn

 

Thanks all - and thanks for the call, Mike. I'll get a pressure tester this weekend to see where the leaks are ... I'm thinking I have one hidden in my valley pan or external head ... if I can't see it I'm taking her to the experts!

 

I had leaks several times as well. The part your are referring to that the hoses connect which in turn feeds into the throttle body, is the throttle body defrost kit. Two little prongs with lines running from your coolant jug i believe. I let mine run and saw it sporadically mist coolant out the gasket. Replaced and havent had problem there since. Knock on wood!

 

Pix of the under $25 throttle body heater kit

 

you could bypass it with some hose for awhile and see, but the parts pretty cheap and rather easy to install.

 

Just remember the real purpose of that is to keep the throttle butterfly valve from icing up and sticking wide open, which might be quite a thrill at I-285 east to I-85 north bound. Icing can happen even at temps just above freezing. Be prepared to shove tranny to N and turn off engine and coast to the side with no power steering and reduced braking.

 

As an up date, that thread on bleeding the system has been corrected to show bleeding the engine cold and while not running, this will help some do a better bleed and less over-heating.