New radiator cap: blown hose.

[Skylarking]

I personally think thermostats get a lot of blame for nothing as they rarely actually fail but get replaced on suspicion quite often. But yeah, since you already had a couple of failures it's a good idea and easy job on the old motors. See how it goes after that and keep checking everything for leaks now you are running at full pressure!

Yep, poor old thermostats get a bad rap but are one of the simplest devices to test if they are working correctly...

One just need a pot, some water in the pot, a bit of wire to suspect the thermostat in the water in the pot, and a thermometer and possibly a veneer gauge to measure the opening.... Oh and an understanding word after you’ve left grease marking in her kitchen

 

[Lex]

Yep, poor old thermostats get a bad rap but are one of the simplest devices to test if they are working correctly...

One just need a pot, some water in the pot, a bit of wire to suspect the thermostat in the water in the pot, and a thermometer and possibly a veneer gauge to measure the opening.... Oh and an understanding word after you’ve left grease marking in her kitchen

You missed the first step. Which can be the hardest. You have to take the sucker out first. On some motors, not very easy at all. And then there is re-fitting it & bleeding the system, (oh what a bitch)

 

[wheb]

Yep, poor old thermostats get a bad rap but are one of the simplest devices to test if they are working correctly...

One just need a pot, some water in the pot, a bit of wire to suspect the thermostat in the water in the pot, and a thermometer and possibly a veneer gauge to measure the opening.... Oh and an understanding word after you’ve left grease marking in her kitchen

This brings back memories!

 

[wheb]

get radiator shop to run pressure test
check for possible head/lim gasket failure

If one of the new hoses go again I definitely will. I'm almost expecting an old heater hose or the rad itself to go shortly...

Blew a head gasket on my first ford. Not an ideal situation.

 

[greenacc]

If one of the new hoses go again I definitely will. I'm almost expecting an old heater hose or the rad itself to go shortly...

Blew a head gasket on my first ford. Not an ideal situation.

You can get a good feel for the pressure in the system just by squeezing the top hose after taking it for a drive. If it's firm and hot but still kinda squeezable like a new tennis ball it's good. If it's absolutely rock hard and red hot, bulging like it's going to blow up you better investigate further...
Holden plastic radiators do have a tendency to snap the top hose neck right off after about 200,000 ks which can be rather spectacular in a traffic jam... Don't ask me how I know but I'm having good success with my replacement radiator from Autobarn at the moment. It's been a few years now since I've seen my coolant disappear in a mushroom cloud on the motorway LoL LoL LoL. Ah good memories.

 

[BowTie]

I think i'm gonna fit a coolant pressure gauge.

And a button that shorts pins 5 & 6 for quick code checks.

 

[wheb]

You can get a good feel for the pressure in the system just by squeezing the top hose after taking it for a drive. If it's firm and hot but still kinda squeezable like a new tennis ball it's good. If it's absolutely rock hard and red hot, bulging like it's going to blow up you better investigate further...
Holden plastic radiators do have a tendency to snap the top hose neck right off after about 200,000 ks which can be rather spectacular in a traffic jam... Don't ask me how I know but I'm having good success with my replacement radiator from Autobarn at the moment. It's been a few years now since I've seen my coolant disappear in a mushroom cloud on the motorway LoL LoL LoL. Ah good memories.

Thanks for the giggle. Been ok so far although did start a bit sluggish this morning. More headaches incoming.