T25 With AAZ conversion running hot, normal?

[ChadMCN]

Sorry for my stupidity and ignorance, please forgive my lack of knowledge.
I have a recently purchased (few months ag0) T25 with a AAZ conversion, 1.9 Turbo. I have an aftermarket analogue temperature gauge fitted and it runs just over 90 degrees. In traffic it hovers around 92 goes up to nearly 100 when going uphill when revved, then back to 92ish.
The temperature sender is from a water pipe from the motor, not the radiator.
When the van is running around 92, the pipes around the motor are hot to touch, but the radiator isn’t, just warm. Yes I have bled the system, no air in the system.
When I rev the van slightly at tickover the temperature drops slightly from 92-93 to 90.
I’m guessing water isn’t flowing around the system, therefore it must be the thermostat or water pump?
I have a van fitted to the radiator which appears new, but does cool down the motor as the radiator isn’t hot.
Q1 Do the campers with AAZ conversion run hot? Is 90 normal?
Q2 Do you need to upgrade the water pump to get is flowing?
Again sorry for my stupidity and sorry if this question has been asked before. I know bikes, but campers very very little.
Chad

[davegsm82]

Best way to rule out the thermostat is to just take it out.

The water pumps on the AAZ/AFN/1Z series of engines have been known to fail, usually the impeller breaks or comes loose from the shaft so you get little or no pump action round the system.

Dave.

[ChadMCN]

Changing the thermostat today so fingers crossed.

[ChadMCN]

Went to change the thermostat and it doesn't have one!

Looks like i'll check the water pump next. Do you have to uprate the water pump?

[Oldiebut goodie]

The water will not circulate correctly without a thermostat in. The flow doesn't get directed around the system if the thermostat doesn't close off the cold engine position - in operation it closes the engine only circulation and opens the radiator side as it warms up.That's the reason for the disc at the 'bottom' end of the thermostat.

[ChadMCN]

I thought without a thermostat the water would be able to flow freely, therefore the engine would run cooler?

[Oldiebut goodie]

No!

[bmouthboyo]

Really? I too thought no thermostat allows the coolant to pass through radiator from cold. Not good for the engine as it is slow to warm up then, but in the case of a hit engine the thermostat would be wide open at 90 plus degrees anyway?

[Oldiebut goodie]

Take a look where the thermostat sits and you will see the orifice that the disc shuts/opens changing the flow route. There must be a diagram on t'internet detailing it - someone else can look! The thermostat doesn't just open the large end to allow flow to the radiator unlike a lot of thermostats that have just that one function.