I work at an engineering workshop these last 6-months - & take calls with these symptoms daily, & get lots of cyl heads in for work (@sako243 had his V8 heads in with work not long back).
I'd think for sure get the oil/water cooler tested if it has one (I know of a few of these fail on industrial engines in the past which give symptoms of HG failure.
The cyl head. Most garages that send stuff in have the head pressure tested for cracks, the valves vacuum-tested (cheap quick way to see if the valves are sealing), then checked for a flat gasket face and refaced.
Ideally you'd get all the valves out anyway, get all the carbon off them & check guides for wear, & seats, valve faces for pitting etc (carbon can help valves seal & hide that the valve/seat is worn). It keeps costs down if you DIY the valve removal, & with luck you'll get away with just lapping-in the valves (though if a head has been well cooked, the warp can distort the centre cyls valve seats enough so they need new seats cutting).
Those pistons with bowl-type combustion Chambers are common on diesels btw.
In the UK as a Vauxhall, that van would be a Combo.
I'd think for sure get the oil/water cooler tested if it has one (I know of a few of these fail on industrial engines in the past which give symptoms of HG failure.
The cyl head. Most garages that send stuff in have the head pressure tested for cracks, the valves vacuum-tested (cheap quick way to see if the valves are sealing), then checked for a flat gasket face and refaced.
Ideally you'd get all the valves out anyway, get all the carbon off them & check guides for wear, & seats, valve faces for pitting etc (carbon can help valves seal & hide that the valve/seat is worn). It keeps costs down if you DIY the valve removal, & with luck you'll get away with just lapping-in the valves (though if a head has been well cooked, the warp can distort the centre cyls valve seats enough so they need new seats cutting).
Those pistons with bowl-type combustion Chambers are common on diesels btw.
In the UK as a Vauxhall, that van would be a Combo.
