Rods 'n' Sods - UK Hot Rod & Street Rod Forums banner
1 - 10 of 10 Posts

·
Registered
Joined
·
247 Posts
Discussion Starter · #1 ·
got a 302 in a nice Pop but water level in rad keeps slowly going down.Had rad pressure tested,all ok no pressure drop.New thermostat working perfectly.No visible water leaks.Engine runs strong,idles perfectly.Plugs seem ok although visibly snootier on one side.Bit of water coming out of exhausts on fire up,no visible white "smoke".Friend suggested head gasket could have gone near water jacket allowing water into exhaust? any ideas? 302 is late 60s,running edelbrock performer 600 offenhauser manifold accel Malory etc"
 

·
Off the Xmas card list
Joined
·
24,347 Posts
If its a standard shape Pop rad then you shouldn't top it right up as it leaves no room for expansion as the water gets hotter. Fit an expansion bottle and see if it is simply expanding and contracting.
 

·
Registered
Joined
·
247 Posts
Discussion Starter · #4 ·
The water in the expansion tank works as it is supposed to and radiator water level leaves room for expansion,level is about 1" above fins.But the water in the expansion tank drops after each run and doesn't go back up to its original level? system was tested warm by the way
 

·
Registered
Joined
·
96 Posts
Just to clarify - does it keep continually reducing the expansion tank level ? or does it just stay low and thats that? I'm just thinking that maybe this is its happy level ??
Was it fine before and is this a recent issue?
Do you have an auto trans? Could be leaking into the box through the rad cooler pipes. Same thing trashed my Vette box. Pull the dipstick on both engine and trans and check for yogurt symtoms!
 

·
Registered
Joined
·
247 Posts
Discussion Starter · #6 ·
hi,no yoghurt except inside breathers and then only a bit.Expansion tank level just drops till it goes below return pipe,it's been an ongoing problem,which I left thinking it would sort itself out!
 

·
Registered
Joined
·
639 Posts
when they did the system pressure test did they try it with the engine running to see if there's any pumping going on or unusual increases in pressure
have you tried leaving the cap off while it ticks over to see whats afoot,
have you looked under the waterpump for signs of a trickle of water/stains- any undue wobble in the pulley /shaft if you push n pull it,or any roughness in the bearings or leak behind the pump
although this should've shown up when you pressurized it all in the test-but only if you were looking there....! lol
just a few random thoughts
neil
 

·
Registered
Joined
·
247 Posts
Discussion Starter · #10 ·
Interesting thoughts,it's not leaking near pump or anywhere external ,the expansion tank is only a small one probably a pint and a bit so I'll run it a few times and see what happens,thanks everyone
 
1 - 10 of 10 Posts
Top