As some of you may know (from my earlier threads) I am currently trying to locate a leak in the cooling system of my 1.8 K series.
Obviously, the smart way to do this is by properly pressure testing the system. The only problem is that the cheapest pressure tester that I have so far located is about £70 + vat and delivery
Although (as a K series owner) I could probably justify the cost, in these austere times, I set about finding a cheaper solution.
The main criteria (as I see it) for a pressure tester are:
This provides me with the guage and a way of releasing pressure when required.
Now, I just needed a way to connect this to the bicycle pump at one end and the expansion tank at the other.
I dealt with the pump end first. Taking a short length of air hose, I slipped a long tyre valve into one end (with a lot of epoxy and a couple of Jubilee Clips). Into the other, I fitted a female PCL connector - to connect to the tyre inflator. The finished assembly looks like this....
A bicycle pump fits nicely on to the valve end and the PCL obviously makes a fine fit to the tyre inflator.
Next, I turned my attention to the cap. Uncharacteristically, after replacing the expansion tank cap last week, for some reason, I discared the old one...DOH!
After a trawl through my 'Lucky dip' box, I turned up an old cap, which is part of my Gunson Ezi-Bleed kit. As luck would have it, it fitted perfectly on to the expansion tank.
It struck me that what I needed was a valve to pass through the central hole in the cap (previously used to feed brake fluid).
Ideally, I needed a valve, which would connect to the tyre inflator and which had a large flange (ooer, sounds a bit rude!) to seal against the hole in the cap.
The answer came during our weekly pilgrimage to Tesco. At the princely sum of £2.20, their replacement bicycle inner tubes were cheap enough to butcher for the valve and not be concerned if it didn't work out. As it goes, work out, it did!
I cut the valve out of the inner tube, leaving am inch or so either side. The plan was that I would then trim this down to fit inside the cap. This ticks a couple of boxes at once; it provides a valve, which will retain air in the system and the extra rubber around the base provides a nice sealing flange.
The next step was to assemble the cap. In the picture below, you can see, in this order...The Gunson Ezi-Bleed cap, the modified bicycle valve and the original sealing washer from the Ezi-Bleed cap.
It's important, when putting it all together, that you fit the sealing washer below the valve flange.
With it all hooked up to the car, all looked good. A benefit of using the tyre inflator as part of the kit soon became obvious; it means that the pump isn't tight against the expansion tank (as it seems to be with some commercial kits). This makes working with it a lot more comfortable.
Here is the kit fitted.
A few strokes of the bicycle pump and the system was soon holding pressure.
Allowing me to check for leaks.
Currently, I think I have identified a number of leaks - the radiator seems to be seeping coolant from the bottom of the left hand tank. There also seem to be little 'fingers' of something green and slimey growing out of the front - so I wonder if some fool / car dealer has lobbed a bottle of Radweld in (although, I'm not sure if this is what it would look like - having never used any such product). There is also a leak from the bottom hose and the top hose is weeping where it joins the head.
All in all, this has justified my decision to shell out for a new rad and remote thermostat kit. I may also invest in an Electric Water Pump mod (cheers for the tip MHM).
Running the engine with the pressure tester attached showed no undue pressurisition of the system, which is good news.
This kit cost me personally less than a fiver to put together. For this cost, no K series owner should be without one. Even if you had to buy the tyre inflator, you'd probably still be in for less than £20. And if you don't have an old Ezi-Bleed knocking around then simply buy a new expansion tank cap and drill a hole in the centre - you can make sealing washers out of the remains of the bicycle inner tube.
Works for me and I can put the money I saved towards a new rad.
Happy days!
Obviously, the smart way to do this is by properly pressure testing the system. The only problem is that the cheapest pressure tester that I have so far located is about £70 + vat and delivery
Although (as a K series owner) I could probably justify the cost, in these austere times, I set about finding a cheaper solution.
The main criteria (as I see it) for a pressure tester are:
- It should provide a way to pressurise the expansion tank through the cap
- It should use a hand pump (not compressed air) to provide greater control over the pressure applied
- There must be a guage to read the pressure and establish if it is leaking away
- Once pressurised, pressure should be retained within the expansion tank / cooling system until you want to release it
- There should be a way to release the pressure when disconnecting the tool
- It should cost less than a tenner .
This provides me with the guage and a way of releasing pressure when required.
Now, I just needed a way to connect this to the bicycle pump at one end and the expansion tank at the other.
I dealt with the pump end first. Taking a short length of air hose, I slipped a long tyre valve into one end (with a lot of epoxy and a couple of Jubilee Clips). Into the other, I fitted a female PCL connector - to connect to the tyre inflator. The finished assembly looks like this....
A bicycle pump fits nicely on to the valve end and the PCL obviously makes a fine fit to the tyre inflator.
Next, I turned my attention to the cap. Uncharacteristically, after replacing the expansion tank cap last week, for some reason, I discared the old one...DOH!
After a trawl through my 'Lucky dip' box, I turned up an old cap, which is part of my Gunson Ezi-Bleed kit. As luck would have it, it fitted perfectly on to the expansion tank.
It struck me that what I needed was a valve to pass through the central hole in the cap (previously used to feed brake fluid).
Ideally, I needed a valve, which would connect to the tyre inflator and which had a large flange (ooer, sounds a bit rude!) to seal against the hole in the cap.
The answer came during our weekly pilgrimage to Tesco. At the princely sum of £2.20, their replacement bicycle inner tubes were cheap enough to butcher for the valve and not be concerned if it didn't work out. As it goes, work out, it did!
I cut the valve out of the inner tube, leaving am inch or so either side. The plan was that I would then trim this down to fit inside the cap. This ticks a couple of boxes at once; it provides a valve, which will retain air in the system and the extra rubber around the base provides a nice sealing flange.
The next step was to assemble the cap. In the picture below, you can see, in this order...The Gunson Ezi-Bleed cap, the modified bicycle valve and the original sealing washer from the Ezi-Bleed cap.
It's important, when putting it all together, that you fit the sealing washer below the valve flange.
With it all hooked up to the car, all looked good. A benefit of using the tyre inflator as part of the kit soon became obvious; it means that the pump isn't tight against the expansion tank (as it seems to be with some commercial kits). This makes working with it a lot more comfortable.
Here is the kit fitted.
A few strokes of the bicycle pump and the system was soon holding pressure.
Allowing me to check for leaks.
Currently, I think I have identified a number of leaks - the radiator seems to be seeping coolant from the bottom of the left hand tank. There also seem to be little 'fingers' of something green and slimey growing out of the front - so I wonder if some fool / car dealer has lobbed a bottle of Radweld in (although, I'm not sure if this is what it would look like - having never used any such product). There is also a leak from the bottom hose and the top hose is weeping where it joins the head.
All in all, this has justified my decision to shell out for a new rad and remote thermostat kit. I may also invest in an Electric Water Pump mod (cheers for the tip MHM).
Running the engine with the pressure tester attached showed no undue pressurisition of the system, which is good news.
This kit cost me personally less than a fiver to put together. For this cost, no K series owner should be without one. Even if you had to buy the tyre inflator, you'd probably still be in for less than £20. And if you don't have an old Ezi-Bleed knocking around then simply buy a new expansion tank cap and drill a hole in the centre - you can make sealing washers out of the remains of the bicycle inner tube.
Works for me and I can put the money I saved towards a new rad.
Happy days!
Last edited: