Flushing the Hijet

The vacuum holds the water Inside if you dont release the cap. But when the system heats up there is pressure and it will also leak and maybe suck in some air on cool down. Inspection cover is behind the seats with a lot of 10mm and 12mm bolts.

Oooh okay thanks, I'm on it...

I can't really get a better visual with the inspection cover off.the leak coming from just above the circular inset bit.

Well that green thing is the water temp sensor so is it coming from there? Mine had a small leak at one time from there. Without looking myself can't say what's above it, maybe Woody when he sees this thread may be able to shed some light on it.

seems to be coming from behind those two bolts slightly to the left above the circle.

You have a rusty leaking core plug that needs replacing and a Cylinder block that needs to be pressure hose flushed out.

Rust from the cast iron block builds up at the bottom of the water jackets and rusts out the core plugs.
You need to make sure after flushing and fitting new core plugs that you run the engine 365 days of the year with Antifreeze mixture as it has a rust inhibitor in it.

Thanks for the diagnosis Woody, what im imagining is a couple of pairs of pliers and maybe a flat head screw driver will get the rusty plug out but just incase im wrong Is there any special procedure i should follow to get them out on the hijet?

Can i pressure hose flush the cylinder block whilst its all still in situ or (and im really hoping not) do i have to take the thing apart to do this...?

Does any one know the best place to get the best core plugs from?

a quick ebay search came up with these

http://www.ebay.co.uk/itm/SWAG-Frost-Core-Plug-Fits-CHEVROLET-MERCEDES-Ng-OPEL-Insignia-Mokka-5073860AA-/142462807295?fits=Model%3AHijet&hash=item212b71ecff:g:vEEAAOSwKJRZgG-x

Thanks again.

I find that the easiest way is to bang a screwdriver through the rusted part and gently lever it out. I can't quite picture in my mind how easy it is to get at the core plug in question. I would advise that you get a complete set and do them all. Also makes it easier to flush all the crud out of the block so long as you can get near to an outside tap or that you have a long hosepipe.
I am in the middle of a job fitting reversing sensors to a newish car at the moment so I must press on with that very carefully.

If you need some more information later on then Email me at : thehijetmaniow@gmail.com

While the plugs are on order with a while yet to wait for delivery, I sealed the leaking plug as a temp fix. Out driving she overheated quite badly. After then the matrix bleed was tougher - the coolant was coming out the heaters bleed nipple with much less of a gush than before. After short drives with no over heating you could still hear lots of air moving through the system. Then I woke up to a leaking radiator. Can this be fixed or do I need a new one??

Hmm don't like it he look of that fluid. What antifreeze is in there? Should be a pinkish colour. Are you sure it's leaking and it's not just water collected at the bottom from when you have bled/filled it? Had a similar scare and turned out it had just dripped there from a slip after topping up. Worthwhile drying off completely (I have a electric blower to clear it away) and checking again.

Yeah you were right actually just coolant drippings from the bleeds!

I've been driving her all over the place and she's doing great. It's almost like she needed a couple day break to get over her wind problem. Looking forward to opening these core plugs and purging the hell out of all I can.

With regards to the fan. It does have another wire spliced off the main connecting wires going off upward. I pulled my mystery switch on dash and I'm not sure if it looks right. Wire missing? Here's a pic of the switch and I took one of the fan wires. What do you guys think? Have I already got an over ride switch set up ?

Also ive read on another post about thermostats that have a lower threshold so the cooling down begins earlier. Wanting to do all I possibly can for her (and for me - being the lucky boy who has to drive her of course) do you guys think it's worth doing?

Not with one wire you haven't. You can see clearly on the two wires on the connector block on the temperature sensor that they have had a blue Scotchlock connected to two wires that would have gone to a switch on the dashboard to give you the overide of the sensor.
You are going to have to do the same. Trace where the white wire goes and if you can find a white wire in the vicinity of the Sensor then that is what a previous owner must have done. Hopefully you can locate the other wire too. If not start afresh.

You haven't got the 3 prong connection sensor and plug to be able to do that on yours.

Hmm interesting.. I wonder why it would have been removed... I have found another disconnected wire that would have gone to the mystery switch on the dash.


The 2 black and white wires are taped to wires that connect to the rear demister switch and then from that little taped together bundle just three wires go off with all the other wires...

I've removed the pvc tape bundling all the wires together below the front of the van but there does not appear to be any disconnected wires down there...