Cooling and Rad Caps
Posted: Thu Mar 13, 2014 12:11 pm
Hi all,
Carried out some major changes in the engine bay over the winter. They stemmed from my kids who are growing too fast. My dry sump tank used to run from the engine bay through horizontal bulkhead and into the front of the passenger footwell. The additional bulkhead I installed reduced the length of the footwell which was fine with smaller children but now they are growing up it became an issue so I relocated the the tank to the front.
This entailed all sorts of other changes including permanently fitting the kenlowe preheater. This is where the fun started. The outlet from the block has a blanking radiator cap on it because I am running an expansion tank. The pre heater pipework has a bleed on the top of it and this is the highest point of the whole system. It is just higher than the outlet from the block.
When I bled the system for the first time the expansion tank was lifted to a point above the engine and with the cap off it bled fine. Once bled, the 13lb cap was fitted and the tank was lowered to its permanent home which is below the height of the preheater bleed and outlet casting from the engine.
When I ran the car, the system was fine - if anything running a little cool (but it wasn't that hot on Sunday).I subsequently ran the car and found a little air in the system that I ended up bleedinhg out following the same ritual as before.
Now - it is possible that the blanking cap isn't sealing that well. There are no apparent leaks in the system so I will check this - but I am looking for a sense check on the logic of the installation (particularly the positioning of the expansion tank which I understood could be located at any height because the system is essentially pressurised).
It could be that the heater didn't bleed perfectly and I will check this too.
As usual, all thoughts gratefully received.
Many thanks
Gavin
Carried out some major changes in the engine bay over the winter. They stemmed from my kids who are growing too fast. My dry sump tank used to run from the engine bay through horizontal bulkhead and into the front of the passenger footwell. The additional bulkhead I installed reduced the length of the footwell which was fine with smaller children but now they are growing up it became an issue so I relocated the the tank to the front.
This entailed all sorts of other changes including permanently fitting the kenlowe preheater. This is where the fun started. The outlet from the block has a blanking radiator cap on it because I am running an expansion tank. The pre heater pipework has a bleed on the top of it and this is the highest point of the whole system. It is just higher than the outlet from the block.
When I bled the system for the first time the expansion tank was lifted to a point above the engine and with the cap off it bled fine. Once bled, the 13lb cap was fitted and the tank was lowered to its permanent home which is below the height of the preheater bleed and outlet casting from the engine.
When I ran the car, the system was fine - if anything running a little cool (but it wasn't that hot on Sunday).I subsequently ran the car and found a little air in the system that I ended up bleedinhg out following the same ritual as before.
Now - it is possible that the blanking cap isn't sealing that well. There are no apparent leaks in the system so I will check this - but I am looking for a sense check on the logic of the installation (particularly the positioning of the expansion tank which I understood could be located at any height because the system is essentially pressurised).
It could be that the heater didn't bleed perfectly and I will check this too.
As usual, all thoughts gratefully received.
Many thanks
Gavin