53 Plate 1.3 Petrol/LPG overheating and radiator emptying after 60miles or more when going uphill after being stationary

Hey,

So i have a 2003 (53 plate) Daihatsu Hijet 16V EFI LPG/petrol.

It tends to overheat after a longish journey about 60 miles or more and it has always happened after being stationary at the bottom of a hill then it overheats while going up the hill.

It doesn't seem to be the fan as that turns on, and there is no leaks in the radiator and there is enough oil.

The radiator empties, not sure if fully but takes about 1ltr or more to fill it back up again with and once this has been done it will run again for 60+ miles all fine with the temp gage below half way.

It has had a rad flush in the garage and hasn't seemed to do anything,

When it does overheat it does so very quickly and i have to stop very quickly, the heating goes cold as i turn this on to try help with the overheating but it strangely goes cold.

Can anyone help me, im pretty new to working on cars as im 22 but willing to give it a go or atleast tell a mechanic what is wrong if its out of my depth.

Thanks guys, any help would be amazing.

Lloyd

Heating goes cold because its lost water so it now has air instead of water in the system. If its not showing up as water dripping from anywhere air has got to be getting into the system.
When you say it looses water, where from, the front rad or into the expansion bottle under the seat?
Firstly check all hoses are tight etc, no rusting clips that may let air in, check or change rad caps, check (even if it has a thermostat) or change it, check fan operation. Bleed it correctly then take stock of whats happening before jumping to any major conclusions about else could/may be wrong.
Probably overheats after a stop as before the air is being pushed through the radiator, therefore keeping it cooler, when stopped the heat builds up as no air flow (especially if fan isnt comming on) and then you put it under load up a hill, slower speed and higher load takes it over the edge temperature wise as you will be adding temp to a base level thats already risen high.
Sounds like mine when I got it, ran with low temp guage, only heated up when on drive stood idleing after a while....no thermostat, removed as previous owner had overheating issues!
Start with the basics first.
Is this van new to you?

and arent the front side vents always cold...
i think they run on a different system..the front ones facing the frontwindow should be hot.
the side ones never get hot if i remember correctly.

just take raggys advice and go step by step crossing things off.
there is loads of info on here regarding overheating... read it

Correct, the front facing vents are always cold. They aren't connected to the heater. (at least this is how it is on a 1.3)

Hey guys,

first of all thanks for your replys!
i have has the van 1.5 years with very few problems.
It loses water from the expansion tank under the passenger seat.

I will try your advise, thanks!

Lloyd

Hey guys,

Update: rad cap under passenger seat was broken, replaced it and fixed most of the problem.
Fan doesn't work now though, think it may have burnt out from being on a lot!
First of all im trying to bleed the system to make sure its not just an air lock stopping it from coming on.
Something weird i noticed while bleeding it, i left the radiator cap off while running the engine after filling and it spewed out a fair bit of water (at first) every 5-10 on a regular pattern, slowly getting less as it spewed out more as youd expect.

Method i used (can skip):
Filled up with coolant from radiator cap with both caps off.
filled untill passenger cap oerflowed, put passenger cap on.
continued to fill from radiator cap till full.
Due to not having a bleed valve (lpg conversion, british imported took them off for some reason) i left the radiator cap off and ran the engine hoping to lose any air out of the radiator cap.
then the weird potential problem occured.
no more coolant could fit after i turned the engine off which i thought was weird seen as it had spewed out about 200ml atleast.

In the hope this is normal and the system is bled i put the cap back on and ran the engine till hot, no action from the fan.
currently waiting for it all to cool off to see if i can fit more coolant in the radiator cap.

Thanks guys!

Lloyd

Your method up to the radiator overflowing is ok. All you need is a bit of water pressure to push the water up into the heater matrix.
Look up above the radiator and you will see a small pipe with a rubber cap on it with a small clip.

Remove the cap as this is where the air is expelled from. If you have easy access to a hose pipe then you can pressurise the system to push the water up into the matrix and expel the air that causes your heater to blow cold.

You could also use a watering can with hosepipe attached with electrical tape.

Either way, the end of the hose that will be going into the radiator neck needs a collar of electrical tape wrapped around the hose 1" from the end of the hose. The collar of tape needs to be a snug fit in the seating of the neck. I use a hose to fill the radiator up. Once it is full up then push the hose into the seating so that the tape collar is making a seal. Assuming that you have already removed the bleeding pipe cap, the air will be pushed out. Push the cap back on at the same time removing the hose and replacing the cap swiftly. Job done. I am going to see if I can find a couple of pictures, hopefully on this tablet. Nope, no joy.

Thanks woodie! amazing instructions but i think my radiator is different, apparently the LPG conversions were altered by the birtish importer and dont have a bleed valve.
I will take a picture of mine to show you, i may be wrong though.
Since this post i have retried the bleed using a slightly different method, mainly caps on while running it, this has seemed to of worked and the fan now kicks in a little below two thirds of the way up the water temp dial and the dial shoots down to mid way. I am hoping this is the problem fixed!
regards the air blowing out only cold, i may have explained this poorly, my writing is pretty bad, never been my strong point but it only did this once throwing all the coolant which i now know is obviously because there is no coolant to get the heat from and no coolant in the heat matrix.
I shall post a picture of my radiator below asap.

This i think is the highest part of the cooling system in the van so i don't think there is a bleed valve anywhere else although i have looked.

Sorry I originally took the pictures for Raggy and Skylark a 993cc which has the cap on the bleeding tube.

Several of my Hi-Jets are LPG and I still bleed them the same way.
Under the driver's seat is a plastic T piece of which one of pipes comes from the Vapourisor Unit.

If you want to be sure then disconect the pipe from that and fill the radiator up and once water is coming out of the T piece replace the pipe. I have NEVER bothered to do that and have never had a problem with it. Some of the T pieces I have seen have a bleed screw which makes it easier to bleed.

Right back to the radiator. When you have the Hosepipe pushed into the seating and the tap on, all you have to do is wait for the water to squirt back into the filler neck from the rubber hose on the side of the filler neck.

Make sure that all of the bubbles are out and it is just water/antifreeze mix coming out, remove the hose and swiftly put the cap back on. That is job done.

Just looked at your last post. The radiator cooling system is no different on the LPG. Prins made a very neat job of converting the 1300's cutting hoses where necessary adding the Vapourisor unit and all the electronic gadgets and ECU.