Hi

1st Problem - I was driving the ute yesterday and after 2mins of entering/driving on the highway 100kph the car spluttered and lost power, drove to the side and idles fine, drives fine but same issue as soon as I go over 80kph.

Struggled and took the 1st exit and drove fine on local roads.

2nd Problem - After 25mins of driving the car got hot and kept stalling. After cooling down a bit idles fine again.

I got it towed home as too worried that I blew the head gasket or might've.

no milky stuff on the rad/rad cap, dipstick and rocker cover cap.

Any ideas?

Can it be that the coil shut itself or the contact points?

i had that once with a fualty cdi

yip, can be the coil.

also check if your carb is not running out of fuel ( my datto deveoped this feature recently ) If so replace fuelfilter, check pump and fuel line.

take off the distributor cap and check the contacts. mine are ####house and always need a light sanding to get the corosion off. also try spraying the leads with crc to displace any moister.
just little things like that can get quite annoying.

I was told to check the oil in the dashpot of the twin SUs
just wondering how much oil or where is the oil level guide on these things?

some have a indicator on them. if not fill them about 3/4 the way up?

yeh could be leaning out and getting hot from lack of fuel.

so adjust the mixture a little tad richer

Sounds like fuel filter, bad fuelpump or ignition.