O.k. Just when I thought things were fine, now I have a coolant leak. I've attempted to trace the leak and thought it was the Upper Radiator hose. So, I ordered both an Upper and a Lower. May as well replace them both, right? Well, after ordering the hoses I come to find out that it's not the hose at all, but the radiator! There's a crack in the seam. I wondered why my temp reading was rather low, but there was no indication otherwise that there was a problem, other than the physical symptoms of course...the green stuff!

So, my question is, "Is there a connection between a Water Pump/Thermostat malfunction and the Radiator cracking at the seam?" I've gone ahead and ordered a new Radiator too, but need I be concerned about replacing the Thermostat and/or the Water Pump too?

I will attempt making these repairs myself, being as they don't seem too difficult. But if it's the Water Pump/Thermostat; I don't think I will take on that challenge.

Thanks in advance for your assistance.

 

if the thermostat is faulty, there will be no circulation and most likely the radiator have cold spot and less load.
i rule out the thermostat.

it's the same thing if the water pump is faulty.

if thermostat or water pump fails, the temperature would be very high.

if the engine have overheated (lack of coolant) and you immediately refill it while the radiator temp is very high... you will hear a popping sound and it will crack the radiator. sudden change of temp.

anyway, the radiator on your model always got problem (clogging). if you will warm up the engine to operating temp and feel different areas on the radiator... you may feel some "cold spots". it means no circulation on that area.

just replace the radiator first if no overheating was experienced.

 

My 87 300E had the T stat stick open and it ran much cooler which alerted me there was a problem.

The WP is a big job which may require air wrenches to break the bolts loose (happened on my 87 XR4TI, I could not hold the pulley and break the bolts without the force of an air wrench)

Any coolant replacement must be done with the pre mixed (or if you mix, NEVER NEVER use tap water, only demineralized/distilled water. Otherwise all the minerals, flouride, chlorine will ruin your new radiator over time).

 

The purpose of the T-stat is to hasten engine warm up. The symptom of a T-stat stuck open is a longer engine warm up time. Once warmed up the engine won't run any cooler since a good T-stat stays open as well.

 

Curious lug, what you say is correct but the proof is in the pudding not in the recipe, my temp guage easily was 1/3 lower on the mark than usual. Given the fact I drive 3.5 miles to work it had no time to get to it's usual spot. It will indeed take longer to reach temp as you state but if driven long enough will reach normal temps and not run cooler, good point to bring up.

 

Yeah, 3.5 miles isn't enough for a good warm up, especially without a working T-stat.

 

Thanks Sleepwalker for your response.

Now, here's the straight-skinny. The vehicle temperature has never run high. I have had issues with it not rising above 50 or so, at times. When I'm running the compressor, the temp would rise to between 80 to 90. When I'm not, it's below 80. Now, I perceive that there may have been non-dramatic leakage all along. But here's the good part.

I've removed the radiator, today. Unfortunately, the daylight had gone by the time FED-EX showed-up with the new radiator (it's a Nissens), and then UPS showed-up with the new Upper and Lower hoses. But, upon opening the drain-****, the coolant was brown and smelled like burnt transmission fluid. What's up with that?

When I removed the radiator from the car and look inside of the radiator, what I saw at the neck was bizarre! There was nothing but a pile of rust, or scale, or something awful. So, I'm wondering, what next? Do I go ahead and install the new radiator, fill it, and then take it to get some sort of pressurized flush or what?

I would hate to take the chance of the new radiator becoming instantly clogged. What should I do?

 

Well, Lugnut:

If this brown stuff is in fact rust and it's been flowing through the cooling system for as long as it has, what effect would it have on the operation of the Thermostat and/or Water Pump?

 

Thanks, IIKings for the tip on the demineralized/distilled water. I would have certainly applied the water hose to it![]

 

was the water inside the radiator got traces of oil or just rusty?

since the radiator is leaking, you need to replace it anyway.

if the temp isn't going up to more than 50 after long driving time, you better check if the thermostat is still present.

some workshops simply remove or keep it open when constant high temperature happens... especially when you got clogged radiator.

test the thermostat by submerging it to a scalding water and see if it opens.