massive air lock in cooling system

[red dave]

☹️ anyone please,

 

just fired up my new built and it sounds perfect. the manual says to run until 92' then fan should cut in.

 

it never

 

the book says air lock contact Caterham. unfortunately they had a power cut.

 

please can anyone advise?

[Tony C]

I was successful by exactly following the assembly guide instructions with the added point of removing the bleed screw completely and topping-up the radiator - with the engine running, after having filled it as per the book. As soon as the radiator is completely full, reinstal the bleed screw and the fan should cut-in soon after. This has worked for several people without needing to raise the front of the car.

 

Ensure you back-fill the heater hose as per the book.

 

Good luck 😬

 

BRG SV 😬 It is only with the heart that one can see rightly; what is essential is invisible to the eye. (Antoine de Saint-Exupery)

[Graham Perry]

There is quite a lot on this in the archive, various techniques have been used.

[red dave]

*confused*have taken the bleed screw out and filled the garage with fliud mount etna style, still no fan. the fliuds are gushing out and i am refilling the same amount as coming out. 2/3 litres so far.

 

any other ideas?

 

cannot find anything in the archives.

[jingars]

I believe that the problem is that the heater is the highest point in the system, not the radiator. You might want to see if you can fill at this point - I'm afraid I don't have the knowledge to help you on that point.

 

My friend had the same problem with his recent build. We were fortunate in still having an engine hoist, so we winched the front of the car as high as it would go - looked scary!

 

Big burp from radiator, more water, job sorted and fan running.

 

Good luck.

[Tony C]

Sorry you've had no luck so far Dave. I too had the Etna experience - messy stuff that Comma 🙆🏻

 

I'm assuming you did everything it said in the build manual, including back filling the heater hose - making sure that you put the cap back tightly on the overflow tank. I didn't and had a MAJOR overflow.

 

Apart from describing my successful experience, as above, I don't know what else to suggest. I also gave all the hoses a good squeezing and even tried applying my mouth to the expansion bottle filler neck to give it a good pressurisation - after giving it a good clean of course.

 

You could try letting it all cool down and start again - not much help I know, sorry. Again, good luck.

[Paul Richards.]

Raise front of car off ground - as high as possible and disconnect expansion tank and raise this up in the air as high as possible.

Ensure that system is full and run with top off expansion tank. As engine warms up, keep loosening radiator bleed valve to ensure no air lock in top of radiator. Air lock should find its way out and great bubbles come out of expansion tank. Be careful as there will be a lot of boiling hot water around.

Keep checking bottom hose for temperature. This should become hot when thermostat opens. Gentle squeezing of hoses should also help.

Good luck.

 

Paul R.

C7PPR

K series that starts when hot!!

[Mark Durrant]

Red Dave

 

I concur with Paul and just be patient...it took over 30 minutes to get all the air out of mine. Also for the first few trips keep an eye the temperature guage and regularly check the coolant level.

 

Good luck.

 

Mark D

Su77on Se7ens

Avoiding the Kerbs

[John Howe]

Dave, if it helps to talk to someone, rather than write - feel free to phone me - 01444 892127

 

JH

Deliveries by Saffron, the yellow 222bhp Sausage delivery machine

[Steve-B]

(roy booth wrote a very good article on this for the se7ens list that i'm copying here)

Here's just about chapter and verse.

 

1. remove the two spade connectors from the fan switch (big round brass thing with two wires on it) in the rad and short them together with the ignition turned on. If the fan runs then your fan switch is toast (common caterham problem). Get one from motor factors or caterham.

(823959481F 1 £9.00 Cooling Fan Switch)

 

2. remove top heater hose, and pour in coolant here too until it leaks out.

 

3. fill the header tank up to the line with coolant.

 

4. raise the front of the car as high as it will go on axle stands.

 

5. ensure the heater is turned on (knob pulled out) remove top heater hose and slowly fill with coolant, keeping the heater exit pipe (the metal bit) covered. Refit the top heater hose and tighten.

 

6. remove the bleed screw from the radiator and start engine, let any air come out of bleed screw then replace bleed screw when engine is up to temp. If using raditor fan switch then ensure fan comes on at about 10-85C and goes off aftrer a while. If using toggle switch turn fan on when guage gets to about 85. and ensure engine gets no hotter.

 

7. remove bleed screw, wipe off opening for coolant tank, affix mouth to coolant tank, and blow until only a steady stream of coolant comes out bleed hole. replace bleed screw

 

8. lower car off axle stands mop up spilt coolant and go for local blat.

 

9. ensure temperature doesn't get above about 80-85 under normal driving conditions with fan off.

 

 

Steve B

Faster than the Speed of Dark Join us on the USA 2005 tour......HERE

[red dave]

*smile* at last the fan works

 

there still seems to be some air in system but i think I'll need to go and buy a 25ltr drum of coolant.

 

the fan cuts in or seems to be more 100' than 92' but it brings the running temp down to 85' this seems ok. oil pressure has dropped slightly under 2 but there is plenty in the engine.

 

any ideas on drying out a fully carpeted garage

 

thanks for all the tips a combination of pretty much all of them has succeeded.