KA StreetKA - Ford KA overheating

Honest John Back Room » Technical matters
What is life like with your car? Let us know and win £500 in John Lewis vouchers | No thanks
View Threaded
Tue 30 Oct 2018 09:35
KA StreetKA - Ford KA overheating - OGW1

Help!! Daughter in law's KA StreetKA has been overheating /boiling. Fan was not working so we did the following:

Checked state of oil for head gasket leak and as there is no water loss as such are reasonably sure H/gasket is fine, so we:

Renewed Fan temp sensor result.. Fan now operating correctly - still overheating

Renewed thermostat - still overheating (old one was ok)

Replaced Heater control valve - still overheating

Had no water pressure (no water coming out of heater hose when removed for test) so had water pump replaced. worked briefly and heater came on but then...... STILL OVERHEATING!!

Tried to eliminate possibility of airlocks by all suggested means..STILL OVERHEATING, and still no heat at heater in car. Totally demoralised now, can somebody please help as the garage is stumped.

Reply | Report as offensive | Link
Tue 30 Oct 2018 10:09
KA StreetKA - Ford KA overheating - elekie&a/c doctor
Did you fit a genuine Ford part heater valve or a generic part?
Reply | Report as offensive | Link
Tue 30 Oct 2018 10:13
KA StreetKA - Ford KA overheating - skidpan

Simple check, is the radiator bottom hose getting warm/hot when it overheats. If its not the radiator is blocked. Either clean out or replace.

Reply | Report as offensive | Link
Tue 30 Oct 2018 10:31
KA StreetKA - Ford KA overheating - OGW1

Cheers will test that as soon as garage gives it back.

Any idea how to get to the top and bottom hose clips to release the pipes for flushing. I have tried every way I can but it seems you need 12 inch long fingers and some weird type of pliers.

Reply | Report as offensive | Link
Tue 30 Oct 2018 10:28
KA StreetKA - Ford KA overheating - OGW1

Generic from euro car parts. Tested it as per Haynes by checking its 'pulse'. Seems fine. Only changed it originally because the inlet pipe section disintegrated as soon as touched

Reply | Report as offensive | Link
Tue 30 Oct 2018 11:00
KA StreetKA - Ford KA overheating - elekie&a/c doctor
Ford had numerous issues with this heater valve, one being a design fault causing an engine overheat problem. I would fit a genuine part.
Reply | Report as offensive | Link
Tue 30 Oct 2018 11:07
KA StreetKA - Ford KA overheating - skidpan

With regards to the heater valve I had issues with 2 on my Puma, presume its a similar part.

First one stuck closed (no heating to the car) and the 2nd stuck open (only heating).

Neither caused a overheating issue.

In the case of the 2nd failure to stop the car getting too hot inside I simply clamped the water pipe, still no overheating.

Based on that I cannot see how its a valve issue.

Reply | Report as offensive | Link
Tue 30 Oct 2018 12:25
KA StreetKA - Ford KA overheating - OGW1

Thanks for taking the trouble to post. I tend to agree with you. The valve was happily pulsing when the heat on the heater unit is set to middle position so according to Haynes that should be ok.

Reply | Report as offensive | Link
Tue 30 Oct 2018 12:29
KA StreetKA - Ford KA overheating - jc2

There are firms that do exchange rads.

Reply | Report as offensive | Link
Tue 30 Oct 2018 13:49
KA StreetKA - Ford KA overheating - Railroad.

I can't believe that the obvious question has been overlooked, or at least been failed to mention, which is. Is the radiator hot when the engine is hot? If it isn't then it's not dissipating engine heat, which means the engine will overheat. The cooling fan, working or not will have no effect if the radiator is cold, but then common sense should tell you that. Once you know whether or not the radiator is hot come back and we'll go from there.

Reply | Report as offensive | Link
Tue 30 Oct 2018 15:54
KA StreetKA - Ford KA overheating - elekie&a/c doctor

"Only changed it originally because the inlet pipe section disintegrated as soon as touched " .So presumably it was ok before the valve change. Bit of a clue there.

Reply | Report as offensive | Link
Tue 30 Oct 2018 16:43
KA StreetKA - Ford KA overheating - KJP 123

You can buy infrared thermometers quire cheaply to check if rad has cold spots.

Reply | Report as offensive | Link
Tue 30 Oct 2018 19:12
KA StreetKA - Ford KA overheating - OGW1

The car is with a garage at the moment and hopefully they will check the performance of the rad.

My problem is that I get sidetracked by the fact I have had serious air locks on at least two different cars which took quite a bit of clearing. The usual tricks to clear didn't work and I had to get creative. So, I still have a sneaky suspicion that air may be the bad guy in this case, but until I can figure out how to access the top and bottom hose clips I can go no further and I am stuffed so to speak!

Any ideas gratefully received.

Reply | Report as offensive | Link
Tue 30 Oct 2018 20:28
KA StreetKA - Ford KA overheating - Railroad.

The car is with a garage at the moment and hopefully they will check the performance of the rad.

My problem is that I get sidetracked by the fact I have had serious air locks on at least two different cars which took quite a bit of clearing. The usual tricks to clear didn't work and I had to get creative. So, I still have a sneaky suspicion that air may be the bad guy in this case, but until I can figure out how to access the top and bottom hose clips I can go no further and I am stuffed so to speak!

Any ideas gratefully received.

You're making the cooling system sound far more complicated than it really is. They're actually very simple. You also have to understand that if the engine has been running too hot for too long then head gasket failure may have occurred. There is nothing complicated or difficult about bleeding any engine cooling system, and it's impossible for air to get into the system unless it's been disturbed and not refilled properly, or compressed air in a cylinder which has breached the head gasket. Air cannot get in unless coolant gets out, and certainly cannot get to the bottom of the full system and get trapped there. That is impossible. To bleed the system shut the engine off and remove the coolant temperature sensor. Fill at the highest point until coolant comes out of the sensor hole. Refit the sensor and top up the system. Refit the pressure cap and run the engine until the radiator is hot. The cooling system prsssure should increase with temperature. When the thermostat opens the pressure should fall slightly as the temperature drops slightly. If the radiator doesn't get hot but the engine is then you have a problem. The thermostat could be stuck closed or the head gasket could be gone.

Reply | Report as offensive | Link
Tue 30 Oct 2018 21:53
KA StreetKA - Ford KA overheating - OGW1

Thanks for your detailed post. Obviously system has been disturbed when the new components were fitted so ingress of air is very possible. If it comes back from the garage and still has problems I will try the removal of fan sensor and re-fill as suggested. I will also re-check the radiator. If none of that works I suppose it leads to the head gasket AAARRRGH! Watch this space.

Reply | Report as offensive | Link
Wed 31 Oct 2018 10:21
KA StreetKA - Ford KA overheating - Railroad.

Some cooling systems bleed easily without the need to remove anything, and others may need to have the highest component in the system which is on the engine side of the thermostat removed to allow air to escape. The coolant being heavier than air will force it out through the open point. Running the engine whilst filling does nothing to aid bleeding, and so fill the system completely before starting.

Edited by Railroad. on 31/10/2018 at 10:23

Reply | Report as offensive | Link