Mystery part.

I expect this may be the first of a few ‘mystery’ (to me) bits & pieces on our ‘new’ OKA.

This is underneath, looking upwards- a complete guess - but is it some sort of adjustable brake bias set up??

Maybe it is a front to rear brake proportioning valve?
It is vital to avoid rear brake lock up on gravel. They tend to "swap ends" and then fall over if that happens.
Cheers,
Peter

To me it looks like a standard high pressure hydraulic valve which I've installed on machinery. So I take it, it is fitted as a line lock on the brake system. Someone stands on the brake pedal and someone else turns the valve shut. Therefore the brakes are now locked on, so making it hard to move/stolen.

Dan.

I suspect Peter is correct and that someone fitted it as a replacement for the rear brake proportioning valve; which is generally seized up on every Oka. It appears to be in the same position as where this was.

more details in this thread www.oka4wd.com/forum/oka-maintenance/1553-load-sensing-valve

Another ‘mystery part' underneath the OKA. Can anyone identify it for me please?

Fuel tank selector.
Selects the source of fuel and directs the return fuel to the tank in use.
www.pollakaftermarket.com/en/products/fu...d-6-port-fuel-valves
Cheers,
Peter

Thank you Peter, that is a very useful piece of info in trying to work out how to get our passenger side fuel guage to work. I discovered that the fuel sender unit has been disconnected, but cannot find any unused wires which could be the ones required. Some (earth?) have been inexplicably cut off.



Do you (or any one) have a basic wiring diagram (or link to one) showing how fuel level sensor, changeover valve & changeover switch on dash connect to each other. I think I may have to re-wire the tank . Single gauge in cab reads driver side one ok, but obviously not the passenger side one. The changeover valve works as we can run off either tank.

I have a replacement tank sensor, but now uncertain if it is needed.

Cuppa, the Pollak style valve also switches the fuel gauge to the selected tank.
This might help?
cdn.shopify.com/s/files/1/0612/8493/file...tructions_2.pdf?1231
Your valve may not be a Pollak, of course. Pollak is ex USA.
Cheers,
Peter

Thanks Peter, very helpful. I haven’t got to the bottom of it yet, but I am now thinking that the solution is likely to be an easier one than I had previously thought. Have traced the ’signal wire’ from the Driver side tank to the changeover valve (which if not a Pollack appears to be an identical copy).. None from the Passenger side tank of course, but as yet I am not certain that the connector plug on the Pollack is wired exactly the same as that in the diagram. Still need to get the fuel tank out too. It seems the only way to do this is to lift the whole motorhome body & subframe up off the chassis by a couple of inches to gain sufficient clearance. Should be able to lift one side only with 2 high lift jacks set up on timber blocks. Have ordered a second HL Jack for the job. A bit drastic but that's how it is.

Pollok valves......
I fitted one to #196 in 2004.
My friend Julian fitted one to his Canter in 2010.
When we were coming back from the Coburg Peninsula in 2021, his failed. It is a serious pain when that happens.
He bought a Chinese copy in Katherine for about the price of a genuine one. It failed a couple of months later. Then mine failed. I already had a spare that I had bought for #077 and I found a new one on Ebay that some guy in Canada bought and did not want.
Now we carry a couple of these for emergencies. One for the feed fuel and one for the return lines.

Just be careful getting the 5/16" (8mm) one. 3 times I ordered from China, 3 times I got the 3/8" (10mm) one, 3 times I got my money back, so if you need one, let me know.
Cheers,
Peter

Next time you need a new one look for a toyota one as they rarely fail.
374 only ever had one tank so when I made and fitted the auxilary tank I just fitted a gauge to it and an electric solid state pump which pumps the fuel into the main tank which avoids a lot of problems with pollack valves.