Club 80-90 Forums

pfield69 wrote: Wish me luck

Good luck

It is often suggested that the crud is a result of using some sort of "Radweld" type product (which blocks thin pipes).
I hope your rad does not start leaking after all this flushing and re introducing anti freeze (which often seems to trigger leaks in weak spots ) Mine did when I had the same issues (a good few years ago now)

As I say "Good luck"

Well today didn't go well. Pressure tester not available for loan and spent all day changing a mini's brakes!! They may be made by BMW but I think they researched them too much and made the like the old one - "pooh"!. 5 year old car with calipers and discs so corroded it was unbelievable.

pfield69 wrote:I noticed that he said temp gauge should sit in the middle. Mine sits on or just below the line which is about 1/4 of scale. As there are only 3 marks, cold, mark, hot I thought this is where it is suppossed to be?

Sounds like thermostat stuck open.
But before jumping to this conclusion, if you leave it ticking over for a long time, does the needle slowly rise to middle (normal running temp), then just past warning light does the rad fan kick in? If this all happens then good, all else is well and it's an open (or missing!) thermostat. If anything else happens you have another problem.
eg if fan cuts in but gauge still low then it's probably temp sender or high resistance somewhere in circuit to it. Test by shorting sender wire to earth - gauge shoud go straight to full deflection right (off the scale!) and red light should flash. Could also be faulty gauge, or voltage stabiliser on back of dash (Does fuel gauge also read low?).

NB You can't test any of this until you have sorted pipework and have bled it fully. As Ghost says, one thing at a time. We can come back to this and help you sort it later

After a long delay due to unneccessary exicetment in my life I believe system is flushed filled and bleed.

I used the quide found here http://www.brick-yard.co.uk/forum/bleed ... 29710.html to do the bleeding process. It didn't quite go as planned but I think we got there in the end although the fuel pumb failing mid bleed (bloody vans) didn't help.

I used rad flush and deionised water to flush, clean and fill. Its also jam packed with anti freeze (pink, mixed 50:50).

I need to check a couple of things with you guys.
1. when bleeding, the water never came out the bleed screw unless the engine was running at ver high revs. Is this as would be expected?
2. The bleed screw on the thermostat houseing should be fully screw down? I ask this as you can unscrew it unitl it 'locks'. Then you can unscrew it some more to remove it.
3. Undoing the rad bleed screw with the engine lets air innot out. Is this right?
4. The engine bay warmer pipe now gets hot. This suggests I've got a better flow through it and to all the pipes coming off it EXCEPT the very last pipe that goes through the bulk head. This is considerably cooler then the rest of the system. What is this pipe for and would it be expected to be cool?

Finger crossed and see if it works

pfield69 wrote:After a long delay due to unneccessary exicetment in my life I believe system is flushed filled and bleed.

I used the quide found here http://www.brick-yard.co.uk/forum/bleed ... 29710.html to do the bleeding process. It didn't quite go as planned but I think we got there in the end although the fuel pumb failing mid bleed (bloody vans) didn't help.

I used rad flush and deionised water to flush, clean and fill. Its also jam packed with anti freeze (pink, mixed 50:50).

I need to check a couple of things with you guys.
1. when bleeding, the water never came out the bleed screw unless the engine was running at ver high revs. Is this as would be expected?
2. The bleed screw on the thermostat houseing should be fully screw down? I ask this as you can unscrew it unitl it 'locks'. Then you can unscrew it some more to remove it.
3. Undoing the rad bleed screw with the engine lets air innot out. Is this right?
4. The engine bay warmer pipe now gets hot. This suggests I've got a better flow through it and to all the pipes coming off it EXCEPT the very last pipe that goes through the bulk head. This is considerably cooler then the rest of the system. What is this pipe for and would it be expected to be cool?

Finger crossed and see if it works

Engine bay warmer pipe... that's a mystery to me
pipe that goes through the bulkhead... again we need an explanation or a picture

engine bay warmer pipe is what I've been calling the radial metal pipe that circles the engine bay. The other pipe attaches to the end of this and disappears through the bulk head. Sorry no pic

Ah.. the bleed ring.. It's the highest point in the cooling system, so air can be bled away into the header tank.

pfield69 wrote: 1. when bleeding, the water never came out the bleed screw unless the engine was running at ver high revs. Is this as would be expected?

Yes, well not "very high revs" but perhaps 2,000 rpm, ie about 1/2 full revs.

pfield69 wrote:2. The bleed screw on the thermostat houseing should be fully screw down? I ask this as you can unscrew it unitl it 'locks'. Then you can unscrew it some more to remove it.

All correct, for normal running it should be fully down. Don't over tighten it, it's only plastic !

pfield69 wrote:3. Undoing the rad bleed screw with the engine lets air innot out. Is this right?

You will have to re-write that as it doesn't make sense. E D I T = Ah, "in not out" which of course is wrong Air should of course come OUT of the bleed screw on the rad. Again you need some revs to get the air out. You can let it get up some pressure, with everything closed, then just crack that nut a turn or 2 to let the pressure in the cooling system blow any air out. DON'T undo it too far when pressure is present !! (= Dangerous to you !!) Tighten it up as soon as water starts to come out (of course )

pfield69 wrote:4. The engine bay warmer pipe now gets hot. This suggests I've got a better flow through it and to all the pipes coming off it

Perhaps you mean the bleed ring pipe that runs around the top of the engine bay ?, in Which case = good

pfield69 wrote:EXCEPT the very last pipe that goes through the bulk head. This is considerably cooler then the rest of the system. What is this pipe for and would it be expected to be cool?

As Ian says, we need a better description or pics of which pipe you are referring to really.

If it is the thick one going to the rad, it won't get hot for quite a long time in this cold weather.
If it is the pipe coming back from the rad, it will take for ever to get hot in this cold weather.
If it is either of the thinner pipes going to the heater, then they will only get hot if the heater is ON

p.s. = if the pipe you are concerned about is a thin one coming off the bleed ring, check (by blowing down it) that it hasn't got any blockages. Blockages in thin pipes are not uncommon on these engines and are bad news. Have we discussed blockages and have I shown "that pic" of a blockage, further up this thread, iirc we have If you do take it off to blow down it, you will have to bleed again. Will be easy now you have done it once. Mind you, if we have discussed blockages, I guess you will have already checked it all before putting the anti freeze in ?

Of course all your checks n stuff need to be done when the stat has had time to warm up enough to open and that can take a while in cold weather.

Radiator bleed screw allows trapped air out. T'stat housing bleed screw allows air trapped in the system to circulate round the bleed ring and into the header tank. As the system builds up pressure that air will be pushed into the top up tank. On a clear (yeah right) plastic bleed ring you can see bubbles going round it, when they stop close the bleed screw down (not too tight or it'll snap off.)

Thanks for all the feed back.

I have cleaned the bleed ring out so I know its clear.

I have attached a pic of the cool pipe section. It is coldest near the bulk head and warms up to quite hot by the thermostat housing.

Another thing I noticed is, that once its nice and hot the filler tank is just over full. That is, If I undid the cap I would lose a small amount of coolant (not the header tank).

Heater are nice and hot. Water is still slightly brown but I don't expect too much else.

The tiny hole in the t/stat housing bleed spigot is clear isn't it ?

Ian

yes. Under high revs i unscrewed it completly as part of the flushing process. Also now the pipe from t.stat housing to bleed ring is hot

pfield69 wrote:yes. Under high revs i unscrewed it completly as part of the flushing process. Also now the pipe from t.stat housing to bleed ring is hot

That's good then.

pfield69 wrote: Another thing I noticed is, that once its nice and hot the filler tank is just over full. That is, If I undid the cap I would lose a small amount of coolant (not the header tank).

This sounds like you are referring to the top up tank behind the number plate ?

If so, this should be 1/2 full to start with, when the engine is good and hot it should be a little over half full, then when the engine is cool again it should go back to being half full.

I hope you do not mean it is filling up to the brim (from 1/2 full) as the engine is run. That would either be because the coolant system is not bled properly, or summat worse

See p.s. below