L322 overheating - Need to bleed every 3 days

My engine (L322 V8 Petrol 4.4) was running perfectly, zero issues and it would get really quiet on idle. One day I noticed a leak on the driveway. Minor thing but being a perfectionist I decided to get the seal and went all out by buying a full gasket kit. My mechanic figured it was a good idea to just do a full gasket overhaul "WORST IDEA EVER" and when he put things back, the timing wasn't done properly.

This led to a lot of issues which have since been 'resolved' somehow by changing most of the stuff (Valves needed replacing, vanos, tensioners were slacking and a host of other stuff. Forgive my vague insight, not that technical on such matters.

So now my main issue is this, the car can be perfect for 2 days max. On the 3rd day if I don't bleed the cooling system, the temperature gauge starts to move. Sometimes it goes to 3/4 then back in the middle and never moves again. The water level never changes. What I realised is that I can pull out the pipe coming from the radiator to the coolant reservoir and no spillage, it takes about a litre of coolant for it to start coming out after some bubbles showing that somehow I am getting air into the system even with zero leaks (pressure test).

I have replaced the sensor, water pump and even the fan. Same issue.

I have a feeling this is related to my engine being opened and somehow on high revs on when it's given a strain air somehow gets into the system and once that is significant I get air expanding in my cooling system causing the temperature fluctuations.

We've done pressure test and even changed the 'master pipe' and nothing seems to work.
Anyone experienced this before?

Do a gas test on the coolant, could be HGF.

churcho said:

My engine (L322 V8 Petrol 4.4) was running perfectly, zero issues and it would get really quiet on idle. One day I noticed a leak on the driveway. Minor thing but being a perfectionist I decided to get the seal and went all out by buying a full gasket kit. My mechanic figured it was a good idea to just do a full gasket overhaul "WORST IDEA EVER" and when he put things back, the timing wasn't done properly.

This led to a lot of issues which have since been 'resolved' somehow by changing most of the stuff (Valves needed replacing, vanos, tensioners were slacking and a host of other stuff. Forgive my vague insight, not that technical on such matters.

So now my main issue is this, the car can be perfect for 2 days max. On the 3rd day if I don't bleed the cooling system, the temperature gauge starts to move. Sometimes it goes to 3/4 then back in the middle and never moves again. The water level never changes. What I realised is that I can pull out the pipe coming from the radiator to the coolant reservoir and no spillage, it takes about a litre of coolant for it to start coming out after some bubbles showing that somehow I am getting air into the system even with zero leaks (pressure test).

I have replaced the sensor, water pump and even the fan. Same issue.

I have a feeling this is related to my engine being opened and somehow on high revs on when it's given a strain air somehow gets into the system and once that is significant I get air expanding in my cooling system causing the temperature fluctuations.

We've done pressure test and even changed the 'master pipe' and nothing seems to work.
Anyone experienced this before?

Click to expand...

Just a thought, do the heads need re torquing after running for a while?

Sounds like a crack in one of the heads will hold pressure when cold ,but opens up when it gets hot ,,,,,,or a head gasket..check the oil for water ,filler cap as a litre every three days is going somewhere...