Won't suck the water from overflow

interested! · 05-13-2011, 12:09 PM

Hi!
My MA70 was having overheating problems , then I received an idea from another MA 70 owner friend .
The set-up : Fabricate a tee-piece to fit into the heater pipe on the inlet manifold side of the engine (-this allows for a free running water flow and allows you to bleed the heater ).-- into the tee-piece fit a 3-WAY ADAPTER for: a metal shrader valve (as used to pump up the tyres ) a pressure relief tap ( radiator drain ) and a 0-30 psi pressure gauge , now put the overflow pipe from the OVERFLOW BOTTLE into a clear container of water.
Using COLD water, pump up the system with a foot pump and watch the gauge rise until the water in the container starts to show bubbles- stop pressurising at this point-this is the blow point, next -( this is important!) -allow the cap to continue to release and note the stop point , if it continues to zero then the cap is not sealing OR there is a leak somewhere -external or BHG? this is for investigation !-release the pressure through the drain valve into the overflow tank -ideal for a hot engine, saves waiting for the system to cool before removing the cap!!!!!!
The cap SHOULD release around 13 psi (0.9 BAR )(taking several minutes to reach this point from cold on a running engine) . , STOP around 6 psi and remain so for a minimum of two minutes, no drop = NO LEAKS!! , run HOT at around 10 psi -- mine does and I am not losing any water now.a real morale booster.
With this in place as a permanant fixture you can get REAL-TIME pressure readout and watch your radiator cap performance.
I took the cap apart and added a 2 thou.stainless steel shim to slightly increase the cap pressure to reach these figures.

05-13-2011, 12:09 PM	#4
interested! 3" Exhaust Join Date: Apr 2011 Location: redhill surrey uk Posts: 142	no vacuum? Hi! My MA70 was having overheating problems , then I received an idea from another MA 70 owner friend . The set-up : Fabricate a tee-piece to fit into the heater pipe on the inlet manifold side of the engine (-this allows for a free running water flow and allows you to bleed the heater ).-- into the tee-piece fit a 3-WAY ADAPTER for: a metal shrader valve (as used to pump up the tyres ) a pressure relief tap ( radiator drain ) and a 0-30 psi pressure gauge , now put the overflow pipe from the OVERFLOW BOTTLE into a clear container of water. Using COLD water, pump up the system with a foot pump and watch the gauge rise until the water in the container starts to show bubbles- stop pressurising at this point-this is the blow point, next -( this is important!) -allow the cap to continue to release and note the stop point , if it continues to zero then the cap is not sealing OR there is a leak somewhere -external or BHG? this is for investigation !-release the pressure through the drain valve into the overflow tank -ideal for a hot engine, saves waiting for the system to cool before removing the cap!!!!!! The cap SHOULD release around 13 psi (0.9 BAR )(taking several minutes to reach this point from cold on a running engine) . , STOP around 6 psi and remain so for a minimum of two minutes, no drop = NO LEAKS!! , run HOT at around 10 psi -- mine does and I am not losing any water now.a real morale booster. With this in place as a permanant fixture you can get REAL-TIME pressure readout and watch your radiator cap performance. I took the cap apart and added a 2 thou.stainless steel shim to slightly increase the cap pressure to reach these figures. Last edited by interested!; 05-13-2011 at 12:19 PM.