K-Series Coolant Eruption

[SM25T]

The fan switch will be marked with opening and closing temps

[nutty7]

 Is the car a 1997 Supersport R, look's very like the engine bay of my old car I sold in 2006. Red hoses and blue Magnecor leads.

[John Vine]

Re #19:

My, that would rival Mount Etna!  (I'd assumed initially you were describing a jet of coolant emerging from the small-bore hose into the expansion tank -- which is normal behaviour for a K fitted with rollerbarrels).   Was all that steam and coolant pouring out with the pressure cap still screwed tight?  If so, that's the likely cause of your problem, together with a (possibly) defunct fan switch.  I just hope there's no serious damage to the head or head gasket.

All good advice above.  If it were my car, I'd do the following:

1. Buy a bleed tee and fit it in the top heater hose as shown in the photo.
2. Replace the fan switch (Chris at Redline, CC, motor factors),
3. Drain the coolant (detach the bottom hose from the rad, and ensure the heater valve is open).
4. Refill with Comma Xstream G30 (just over 5 litres ready-mixed, IIRC), Add this via the bleed tee.  When coolant appears in the expansion tank, open the rad hex screw to remove any air trapped in the rad.
5. Fit a new pressure cap on the expansion tank.

JV

[Geoff Brown]

Don't forget to include the heater in the bleed process..............if there is one.

Two K Series & never had a problem - am I missing something?

[goodcoffeecode]

Thanks JV.

Bleed Tee ordered. Already ordered a new pressure cap and the G30 (both should be here by tomorrow).

Given that I could add more than a pint of water to the radiator, isn't it more likely that the fan switch works, but it just wasn't in the fluid? Or, are you suggesting changing it "just in case"?

How does one ensure the heater valve is open (and where is it!)? 

Thanks.

[goodcoffeecode]

nutty7 - I'll check the logs...

[John Vine]

Or, are you suggesting changing it "just in case"?

Well, you could leave the old one in for the time being and see whether the fan comes on under normal road conditions, and simply replace it if it doesn't.

Or, you could remove it and test it by dipping the brass bit in a pan of boiling water.  Of course, you'd need to connect it to a small circuit with battery and bulb.

By heater valve, I meant the heater control knob by your right knee.  Make sure it's pulled fully out.

JV

[rj]

Is it me or does it look like the sensor (No 5) has snapped from the water rail?

Depending on which ECU you're running, this could control the fan, and if the sensor is broken there's no fan!

 

I have had issues if I didn't cool down the engine properly following a track session. The water flow at idle is insufficient to handle the accumulated heat and the heat from the primaries. The water rail is very (too) close. In the end I added an electric booster pump that kicks in when the water temperature is above 85 degrees. This has cured the issue.

[nutty7]

nutty7 - I'll check the logs...

Is the number plate light covering the hole where the spare wheel carrier bolt is normally. The carrier was cut off.

[jackb_ms]

Hello All

Talking about air lock, I've added a bleed scree on my car and i'm never know 100% if the air is all gone.

I've made a little video https://www.dropbox.com/s/b1yuaqzvi2j0ny9/MOV_0869.mp4?dl=0 

Could some confirm if the little bubbles are normal or it means there is still some air wanting to get out.

Cheers

Jack

[cobaltcodd]

At the start you say this  "tiny bit of steam coming from somewhere in the radiator" - is that steam on the outside?  Is there a pin-hole leak in your rad causing you to lose coolant - so the system eventually boils through lack of coolant?  So changing the switches, caps, thermostat etc etc is not going to addres the root cause of the overheating

 

[ScottR400D]

Unless I misunderstood he poured cold water on the radiator to cool things down? 

If that’s right it would have got in the fins and could take a while to evaporate. 

[goodcoffeecode]

OK, so I now have all the parts I need (Expansion tank cap, Bleed Tee, hose clamps, coolant). My plan is to:

1. Fully open the heater lever near my right knee (by pulling it towards me).
2. Remove the lower hose from the radiator in order to drain all the coolant.
3. Randomly squeeze and massage the hoses in order to remove any stubborn fluid.
4. Cut the top heater hose with a box cutter, insert the Bleed Tee, and affix 2 hose clamps to secure it in place.
5. Replace the lower hose to the radiator!
6. Remove the expansion tank cap
7. Add coolant via the Bleed Tee until I see coolant appearing in the expansion tank
8. Unscrew the hex thingy at the top of the radiator in order to help get rid of any air
9. Continue adding coolant to the Bleed Tee until it comes out the hex thingy.
10. Tighten the hex thing
11. Screw the cap on the Bleed Tee
12. Screw on the new expansion tank cap

I'll then run the engine, let it get warm, check the levels in the expansion tank, and confirm that the fan comes on as expected. Once cool, I'll also take a look in the hex thingy to make sure there's no air.

Questions:

1. I'm guessing I'll dilute the coolant 50:50. Is that correct?
2. Have I identified the correct place to insert the Bleed Tee in the attached photo (white hatched rectangle)?
3. Should I first will with water and run the engine in order to "clean" the system?
4. Have I missed anything?

[John Vine]

A few comments...

I'd do #6 after #1

#9 won't be needed if coolant is already visible in the expansion tank as the hex screw is lower.

Re your Qs:

1 - yes, if you're using G30 concentrate. Dilute with distilled or de-ionized water.  If you happen to have a dehumidifier in the house, you can use the condensate from that (which is what I do).

2 - yes.

3 - not necessary.

4 - I don't think so!

Good luck!

JV

[goodcoffeecode]

Excellent, thanks John.

[SM25T]

Don't shorten hose as you fit bleed tee. Useful to be able to raise tee to be higher than anything.

[Wrightpayne]

I dont think its a bad idea to flush it. When you cut the heater hose, put the garden hose in each end in turn while blocking the other, letting water run out of the disconnected rad hose.

Ian

[goodcoffeecode]

UPDATE...

Firstly, I rolled the car down the slight slope from the garage to tip it forward. I then pulled the heater thing in the car to open that circuit. Removing both the top and bottom hex screws resulted in about 1 litre coming out. When I cut the top heater hose (to fit the bleed tee), about another litre came out. Once the bleed tee was fitted, blowing into it forced another volume of coolant out.

Once suitably drained, I screwed the bottom hex screw back in.

I poured 50:50 G40 into the bleed tee until I saw coolant coming from the top hex opening. I then screwed that back in. I continued until coolant was in the expansion tank. Squeezing the large hose connected to the top of the radiator allowed more coolant to go in the bleed tee. I think I should have put the expansion tank cap back on earlier. For a while, I could pour coolant into the bleed tee, which wasn't topped, and the expansion tank would further fill.

Once on level ground, I used a turkey baster to remove excess coolant from the expansion tank!

When I ran the engine, it took about 5-10 minutes to get up to just under 90c. The top fat hose was hot, as were the 2 smaller hoses going to the heater. When I opened the heater lever, the remainder of those small hoses also got hot. However, the lower fat hose connecting to the radiator remained cold.

The fan never switched on. I could have run it longer but, as you can see from the photos, the expansion tank was getting very full.

I'm going to wait until everything has cooled down and then open top hex screw to see if there's an airlock there.

It feels as though this isn't quite fixed, so interested in people's thoughts please. Thanks.

[SM25T]

The bottom hose won't get warm until the thermostat opens. The fan comes on after that when the water in the top of the rad gets to switch trigger point 92 ?

[SM25T]

Please tell us you didn't fill it nose downhill. When cool, remove expansion cap slowly and see if level drops as coolant settles down into circuit to replace air. Should have kept heater valve open the whole time to ensure it fills with coolant. Raising the bleed ter above greater level helps air escape, as the heater matrix is a common airlock point. You want to squeeze the fat bottom hose a lot too.

[Bricol]

Did you change or check the fan switch?  From your first problem, it sounds to me as though the switch has failed - it only overheats when stood, ie when the fan would kick in.   If you don't know the switch works, then the rest is pointless . . 

My technique:

Heater valve open.  

Bleed screw cap on.

Radiator bleed screw shut.

Fill expansion tank until it won't take any more.  

Loosen/remove radiator bleed screw - let air out until coolant runs out - watch expansion tank level - close screw and top up tank if necessary.

Lift bleed tee so air will rise to it - lower it and remove cap - coolant runs out - watch expansion tank level - top up if needed.

Close bleed tee. 

Start car - top up expansion tank to brim and go through radiator bleed and bleed tee again, carefully, as its getting hotter - watch tank level - top up - or even release bleed screw to drain it lower.

Put tank cap on and leave until rad fan kicks in - very carefully loosen bleeds to check for air - its now very hot and under pressure.

All done on the level, and has been each time I change coolant since 2001 . . .

[goodcoffeecode]

SECOND UPDATE:

Yes, I did fill it whilst it was slightly pointing downhill :(. Once cool (after the first startup) I topped up the radiator via the hex screw. I also removed some more coolant from the expansion tank with the turkey baster.

I then did a second start (both starts were done on the flat).

This time the temp stayed at around 80c for at least 10 minutes. Once again the expansion tank filled with coolant - still not sure if this is normal? Given its name, maybe?

Oddly, the temp then rose to 90/95, stayed there for a minute, then dropped back to 80. However, the fan never came on.

The temperature then crept up to nearly 100 - again no fan.

When I pulled out the heater lever and put the fan on, only cold air came out. I suspect there's an airlock at that end now, but I'll get rid with the bleed tee once cool.

So, I'm think the fan sensor thing has failed. The fan itself seems to be good as I can force it on by connecting the 2 wires.

[Orange]

This sounds very similar to the issue I had. I turned out to be a defective thermostat that did not open despite this being new a year earlier (replacing a thermostat with no centre) bought a new one and tested it before fitting and filled as per earlier advise.

I would take your thermostat out and check it opens in hot water as a next step.

[SM25T]

Do the fan switch first, cheap and easy to replace. Thermostat is a swine to get at.

[Geoff Brown]

When I had K series I always bled with the radiator top plug out & stood well back as there can be some belches. Then once satisfied screwed it in tight. OK you need asbestos fingers & be quick but it works.

Fan sensor & main T stat failure a common problem with K series.

Trouble is after 16 years of K series ownership never a problem! Luck of the draw?