Mysterious oil usage...

Hi, on my Hijet, I have a problem with it using oil quite badly. Every 2 or 300 miles the level drops below the low mark and I have to fill her up again. On its MOT certificate (Done before I bought the vehicle) There is an advisory saying that the exhaust emits blue smoke when accelerating, but after having taken it to several mechanic friends and a garage with experience of Hijets, they saw no blue smoke when tested. There isn't any obvious leak either, there is a wet patch on the engine mount below the filler cap which I am planning to clean up and keep an eye on. But no patches of oil under where I've parked at all. It only appears to use it when running. Any ideas on what the problem could be?

Also, while I'm here, my van has a fully functioning foglight switch, which only lights up when the tail lights are on, but there is no foglight at the other end. Is it supposed to be a separate light at the opposite end of the bumper to the reverse light? And is it a legal requirement to have one? This was an MOT fail, but presumably passed when the tester found that there wasn't a foglight in the first place. I also have an occasional problem where the engine fuse will blow for no apparent reason, and I replace the fuse and it will run quite happily for weeks on end without a hitch.

Specs if it helps:

1996 Hijet, CB-42 engine, Petrol, Van.

Any answers would be greatly appreciated, thanks.

Most likely burning oil, get someone to follow you, nail it hard in 3rd, let the throttle off, id bet they see smoke?
Foglight is seperate below bumper on o/s, its a legal requirement on your van, cant see how it passed without it? Maybe worth getting the van checked over as. if its an oil burner the emissions will be higher. Basically, how trustworthy is an MOT that passed an obvious fault?

If it is burning the oil, is it likely to be via the piston rings? I checked it with the garage and after checking the engine over while running, he reckoned it wasn't the piston rings, due to no pressure in the oil bay when he put his hand over the filler hole. If it is something else, then what is it likely to be, and how much is it likely to cost to get it fixed?

Having had a thorough look at the back of my van, there are the light clusters, the number plate light, and the reversing light, but no foglight whatsoever. Looks like I'll have to fit one. So it's supposed to be under the bumper on the same side as the reversing light?

Edit: Ah, I see from Logi's pics where the foglight is meant to be. Definitely isn't there, not even sure the bracket is. There's one on Ebay for £8 right now though, so I should try and snatch it up, although it looks a bit worn out to me. Is it worth going for? Look up Daihatsu Hijet rear foglight on Ebay, I can't post the link.

You should get a bolt on rear fog light from Halfords around £6. I had to get one for my LHD van for MOT.

Waz

£10.99 on their website atm. At the moment I've taken one off an old Land Rover 110 (No longer used on the road) we have here and I'm fashioning a bracket to mount it onto my van.

gon up a bit since I bought mine 24 year ago

Waz

I would check the exhaust manifold when cold to see if it is oily as ours leaks from the dizzy mount and drips onto the exhaust no oil patch but does loose oil and only smells from time to time.

No patch on the exhaust, but there is a wet patch on the engine mount beneath the spark plugs which I previously attributed to being a bit clumsy with the oil can, but now I'm thinking otherwise. I've wiped the area down, and will drive around a bit to see if it reappears. The garage did say it could be coming from the rocker cover. If this is the case, how much is a gasket likely to be?

Not a lot I would think or get a tube of blue hermatite then you have loads for anyother repairs.

No obvious leaking around either of the gaskets, a bit of staining but nothing to justify the amount of oil I'm losing. Could it be the valve seats? If not piston rings or a leak, what else could it be?

valve seats is a no but the valve stem seals would show as smoky when cold or if really bad the really smokey all the time similar with piston rings.

Well, it puts out a fair bit of white smoke under load when cold, but that clears fairly quickly and seems to mostly be condensation from inside the exhaust. A recent thing has also occurred when I fire it up, the fumes smell very rich, could this be a symptom of the oil usage, and if so, does it point to any particular cause?