Coolant level in the radiator - also throttle sticking

[jammy_basturd]

My 5 had a coolant leak a week or so ago, so last weekend I changed the water pump as the leak appeared to be coming from this area (also changed the oil seals and timing belt at the same time). Filled up with new coolant, hadn't cured the leak, it was coming from the pump inlet pipe. Used some Rad Seal to cure it for the time being and it seems to have stopped that leak.

I filled the coolant up to about 1cm below the filler neck on the rad, and midway between low and high marks on the reservoir. Brought it up to temp and topped up as necessary.

A few days later I checked the levels again and all the coolant in the reservoir has gone and the level in the rad was below the fins. I looked for another leak but couldn't find one, so I assumed it was down to an air lock and topped up again.

Checked it again today, and whilst their is the correct level in the expansion tank, the level in the radiator has dropped below the fins again. This isn't normal is it?!


The other thing I've noticed, is that the throttle seems to be sticking occasionally. Sometimes when I'm sat out of gear the car will idle at anything between 1k rpm and 2k rpm, and when I change gear the revs don't drop. Other days the car runs as sweet as it's ever done.

It's a 91 Mk1 Eunos by the way.

[MX-5 Lazza]

Well you should get rid of that Radweld asap - Mk1 rads get blocked easily enough as it is! Do a full coolant flush and replace with the correct coolant mix. As for the source of the leak, it might well still be the same spot or it could be a number of other places. A crack in the rad is fairly common as is a pin-hole in the pipes to the heater matrix.

And the idle - it's likely that the idle control valve is gummed up. Remove it, flush it out with petrol/white spirit/carb-cleaner etc. and replace. After that, set the base idle correctly.

HTH

[jammy_basturd]

Thanks for the advice.

However a slightly new development. Was on the way to work this morning, nearly there when I stopped at traffic lights. Had a bit of steam coming from around the headlights. Managed to get to work, popped the bonnet and there seems to be a lot of coolant on the drivers side of the engine. Mainly under the inlet manifold, over the alternator, a bit on one of the cooling fans. I can only assume there is a pin hole in the radiator. Think I may order a new rad and hoses today and just change the whole cooling system!

[Firefox1]

Just be aware that there is a coolant hose that runs from the thermostat housing to the oil cooler which has the oil filter mounted on it, another hose runs to the back of the block below the coil pack. If it's the oil filter hose that's gone it's an absolute B****rd to replace, it took my son and I around an hour just to remove the spring hose clip.

[towelie]

Firefox1 said:

Just be aware that there is a coolant hose that runs from the thermostat housing to the oil cooler which has the oil filter mounted on it, another hose runs to the back of the block below the coil pack. If it's the oil filter hose that's gone it's an absolute B****rd to replace, it took my son and I around an hour just to remove the spring hose clip.

i used a clamp type thingy, not sure what the name of it is, but its basically a small clamp on the end of a cable connected to a handle which you squeeze and it clamps.. took less than 5 mins too do.. i can see how it took you a while to do, as it is in a very awkward position! had to use a knife on most of the hoses as they weere welded on !

there you go, bit expensive, but had them lying around

http://www.machinemart.co.uk/shop/product/details/...

Edited by towelie on Friday 4th March 09:27

[Firefox1]

Looks to be an ideal piece of kit but I won't need one now as I used normal hose clips. Mine went first under the coil pack it's nearly as bad but the AA man did that one as I had no tools with me, we did a temporary repair by cutting off about 25mm and refitting it.