cooling on kseries 1.4

[stuart147]

Since owning my 1.4 k series Classic ,I have always been concerned about the cooling system on it. No matter how far I go or how hard I drive the car, the bottom hose barely gets warm, never mind hot. "Experts" have had a look at the car and have given it the all clear. I still have this nagging doubt about it. How hot should the bottom hose get when driving normally?.

[rj]

Not hot as you've got air passing the rad when you drive.

 

The thermostat adjusts the flow to keep the temperature right.

 

What happens if the car is steady? I'd imagine it would get warmer.

[rj]

Not hot as you've got air passing the rad when you drive.

 

The thermostat adjusts the flow to keep the temperature right.

 

What happens if the car is steady? I'd imagine it would get warmer.

[rj]

Not hot as you've got air passing the rad when you drive.

 

The thermostat adjusts the flow to keep the temperature right.

 

What happens if the car is steady? I'd imagine it would get warmer.

[Stationary M25 Traveller]

Shaky server ..... now BC postings are multiplying !! ooh-err missus !

 

 

[rj]

Got a server error and gave up 😔

 

First double post ever, and then it was even triple!!!

[stuart147]

I have never felt the hose when the car is left running stationary.I know that if in traffic, the fan comes on as normal and the temp guage never reads above normal 80ish deg's

[rj]

Got it again

 

 

This time I knew better

[Mick Day]

If the bottom hose isn't getting hot it means that either your rad is super efficient or water is not flowing adequately through the rad. The rad may have an internal blockage or the thermostat may not be opening properly or you may have an air pocket near the thermostat housing. Here's what I do when I fill the cooling system:

1.Make sure the drain plug is in place (been there splashed my feet! ) & remove the bleed screw in the rad.

2. Jack up the front of the car, open the heater valve (no heater makes bleeding easier) & poor coolant in gently until it starts to flow out the bleeder. Put the plug in the bleeder. For a fresh install it's about 4.5 litres coolant, less if the water in the block hasn't been drained.

3. With the cap off the expansion bottle grasp the bottom hose & squeeze until your fingers get tired. You will hear the occasional gurgle of air & the contents of the expansion tank will drop. Pour a little coolant in to bring the level up. Now do the squeezing trick with the big "J" hose that enters the thermostat housing.

4. With the cap off start the car & bring temperature up to about 40 deg C. Keep squeezing the bottom hoses with the engine running but (H & S noddy notice coming) don't burn yourself or get your hands tangled in the alternator belt.

5. Take the temperature up to about 60degC & put the cap on the expansion bottle.

6. Now take the temperature up until the fan kicks in. At this point the top & bottom of the rad should be hot & the bottom hose & metal joining tube should be too hot to keep your hand on for any time. Carefully crack the rad bleed screw to let out any air.

7. The temperature should rise, the fan kicks in & the temperature should fall back again quite quickly.

8. Once you've done all this & if the bottom hose is still cool you need to investigate further.

9. Try draining all the coolant out, removing top & bottom hoses & forcing water through the rad with a hose. Do it from both bottom & top ends. It should flow fairly freely. At this stage flush out the rest of the system with the hose poked in the top hose. You then have an opportunity to refill with fresh coolant.

10. Change the thermostat as it may have failed partially closed & if so will only partially open. This usually results in overheating. It could also have failed fully open resulting in the system taking an age to come up to temperature.

11. You may have an exceptionally efficient rad that rapidly knocks the temperature back. It could be that a previous owner fitted a race rad?

12. If after doing all this & the bottom hose is still coolish but the engine temperature remains stable at your indicated 80degC then you could just live with it.

 

[stuart147]

Thanks for that detailed answer Mick. The experts have bled the system and given it the all clear. I think that I will just have to live with it. I will certainly keep your reply in case I ever need to drain and refill the system.

[Richard Price]

stuart147

Did you get my blat mail 🤔

[stuart147]

Only just. At work at the mo, so will e-mail you this evening.

[Richard Price]