Hi,
I have replaced the 3 plastic flanges, most of the coolant hoses and pinned the coolant lines. I have now blocked the engine coolant system and will pressure test the coolant system at 1 bar/15 psi before installing the motor in car. Better to discover leaks now while they are easily accessable...
Should I fill the engine with water before testing or can I just do it without? I was thinking air is very "thin" vs water and maybe it will show a "false" leak that would not have occured with "thick" water in it...?


How long should I pressure test it?


Thanks

 

i would use water since it will bubble with pressure and you might not see it with air. shouldnt take long to see if theres any leaks

 

Hi,
Yes you are correct. There was a tiny leak, but could not find it with only air. Filled with water and I could see some drops leaking from my blocking device...
Fixed now and pressurised to 1.0 bar. Have been holding pressure now for 2 hours. Will hold it pressurised over night and check in the morning.
Fingers crossed...
Thanks

 

It has been holding pressure for over 12 hours now, so I suppose it is ok.

 

Holding pressure that long is definitely good to go

 

Yes I just released pressure after about 22 hours and was still holding fine. Should be ok
Thanks