BMW radiator leak free at last but not sure about the bottom hose.

[Vince70]

Yesterday I finally got around to getting some coolant for the car after changing the radiator and water pump and I ran it up to temp and tried to bleed the system but I seem to have an airlock as I can’t get the heater working.

 

Now and for some reason the bottom hose and bottom half of the rad are still cold plus I’m having trouble getting pressure on the hoses.

 

The needle though is staying nicely in the middle of the gauge.

 

I just wondered is it safe to run the car like this to see if I can get rid of the airlock.

 

Also I undid the bleed valve on the new pattern part rad and the thing just snapped off so I has to take the one out of the original unit which is now back in the new rad and I don’t really want to touch it as although it fits the thread is slightly different.

[dollywobbler]

Doesn't sound terribly safe. I'd try wedging a cut-down bottle into the rad cap or expansion tank to try and create a higher bleed point, or try parking the car on an angle so the cap is the highest point in the system.

[Shirley Knott]

Or pull another hose higher up in the system to create a bleed point and drain/refill again?

 

Or, if you have a Mityvac/Pela device you can adapt them to suck coolant right the way through the system getting rid of airlocks too....

 

Daft question: Did you have the heaters set of full when draining/refilling and warming up to ensure the matrix was drained and open to accept new coolant?

[Parky]

Pela is a good idea. There is an MG Rover forum post where a guy does this very thing:

 

http://forums.mg-rover.org/mg-zt-rover-75-sponsored-rimmer-bros-90/how-vacuum-refill-coolant-system-using-pela-6000-rubber-bung-315806/

 

A Renault mechanic I knew used to run a 16 and when changing coolant he would drive about with a bleed nipple slightly open to purge the air. Very high risk strategy but it used to work for him.

 

I would be careful though, I ran an old Renault 5 with an airlock and eventually steam pressure cracked the head - core plugs were fine, the head cracked instead. I thought I had done everything right (even removing the expansion bottle and tying it to the bonnet so it was well above the rest of the engine) but obviously had a bubble somewhere.

[dollywobbler]

You can usually get most of the air out by 'burping' the coolant hoses. If there's no water in them, it sounds like something amiss.

[Vince70]

I will pop my car over my parents house tonight as they have the steepest drive imaginable so hopefully it will save me putting it up in the air to get rid of the airlock.

 

What’s really worrying me now is the top bleeding screw as although I got the old one out alright after the top snapped off it the one off the original rad has a much thinner thread and I can’t get another as the new radiator is a horrible pattern part so no other Bmw bleed screw will fit anyway.

 

I asked the Ebay seller about it hoping that I could buy another but the seller isn’t replying.

[fordperv]

I have been known to drive around the block without the rad cap undone to shift stubborn airlocks ive not broken anything yet, I suggest jacking the front up and manually burp the hoses as its running as a start point though

[Vince70]

I’ve been in touch with the seller of the rad to ask if there’s anyway I could have a bleedscrew as it won’t take a bmw one and got a no as we don’t sell them so basically the new rad is scrap as it’s impossible to get a bleed screw for it and its a crap Chinese pattern part at the best and the plasticfeels like the stuff that airfix models are made of.

 

It cost me £54 so It’s a case of buy cheap buy twice I think.

[Tadhg Tiogar]

... The 635's brakes are shite too... and dead. ....

Have you experienced E24 brake fade yet?

[fordperv]

I’ve been in touch with the seller of the rad to ask if there’s anyway I could have a bleedscrew as it won’t take a bmw one and got a no as we don’t sell them so basically the new rad is scrap as it’s impossible to get a bleed screw for it and its a crap Chinese pattern part at the best and the plasticfeels like the stuff that airfix models are made of.

 

It cost me £54 so It’s a case of buy cheap buy twice I think.

Can you not take it to your local fixings place to see if they have anything suitable?

[DodgeRover]

I’ve been in touch with the seller of the rad to ask if there’s anyway I could have a bleedscrew as it won’t take a bmw one and got a no as we don’t sell them so basically the new rad is scrap as it’s impossible to get a bleed screw for it and its a crap Chinese pattern part at the best and the plasticfeels like the stuff that airfix models are made of.

 

It cost me £54 so It’s a case of buy cheap buy twice I think.

Is the bleed screw into metal or plastic, if it's metal you could always tap it to a sensible thread that you have a screw for?

[dome]

I've had results on both my S Type and something else I can't remember-when all else failed i took them out and kicked fuck out of them. It worked for me on both occasions-airlock gone, heater working and level down a bit.

[Dave_Q]

These can be a bit of a shit to bleed, i think the approved method was:

 

 

Fill the engine with coolant through the top hose, point it up a bit so gravity helps

 

Reattach the top hose and fill the rad

 

Start it up, heaters on full

 

Crack open the bleed screw on the radiator a bit and hold it at about 1500rpm with your hand on the throttle body

 

You should get a small jet of water coming out with the odd burp/interruption, keep going for a couple of mins until you reckon there is no more air (may need to keep topping up rad)

 

Close the screw while still keeping the revs up

 

Check if the heaters are warm.

[Dave_Q]

Could also combine the above with wot dome sed, these things are from the days of sizing the radiator a bit big just to be safe, it will never get warm enough to open the thermostat just idling on your drive, unless its fucked.

[Vince70]

After the fiasco fitting the cheapo pattern part radiator the other day and the bleed screw breaking I’ve decided to bite the bullet and buy another and have found a Nissens rad which are supposedly top notch.

 

Now the problem is I don’t know which one I’m supposed to have as the part number comes up as 60623 or 60623A

The one I’ve found for my Z3 is 60623 and just wondered what the difference is as my car is quite Poverty spec manual in it has no aircon or an oil cooler.

Would either be ok.

[spike60]

I would reckon A has a built in oil cooler for an auto box and the other doesn't. Ask the seller.

[Shirley Knott]

Nissens are kind of mid range tbh...

 

I fitted a nissens rad to the Golf (£59 iirc) a year and a half back and no issues so far though.

[Vince70]

Cheers Joey

I’ve just ordered it as I emailed Nissens direct and got an answer instantly back that the A is an internal thing so isn’t anything to be concerned about.

The next job tonight will be to clean up my trusty pela pump as it’s covered in oil and drain the coolant.

[Guest Hooli]

According to the chart you put up the 'A' is part plastic & weighs less.

[Vince70]

The new radiator arrived today and the quality is far better than the other thing I bought so I got it fitted up and no airlocks this time which I’m glad about but I have a small leak now from one of the hoses but I guess that’s to be expected with 22 year old rubber.

 

So I bought some cheap silicone things in red as I thought at least it matches the seats lol.

 

I also bought some more blue premix antifreeze/coolant from ECP again so that’s now 15 litres lol

[The Moog]

Plus you will definitely be quicker with red hoses!

[Vince70]

So today I took the leaky bottom hose off as I really want to be driving the old girl so I also bought a NOS bottom hose from Ebay as it should arrive sooner rather than the silicone pipes.

Although the original bottom hose doesn’t look bad from what I can see so I guess I’ve got some stuff to throw in the spares pile now lol.

[Vince70]

Thanks for all the help and I now have a car that holds coolant and it also has snazzy red hoses so it makes it go twice as fast.

I had a bit of leak from the bottom hose but I found that losing my temper helped as I thought I might as well just tighten the jubilee clip to max tightness as a kill or cure and that did the trick so I now see why manufacturers use those horrid clips that are a pain to remove on moderns lol.

I have noticed though that the bottom hose isn't quite as hot as the top hose and just wondered if that's normal.

[Shirley Knott]

^That's normal.

 

As the coolant passes down through the radiator it gets cooled, that's the point

[DodgeRover]

Top tip tightening jubilee clips with a socket and never a screwdriver, you can get them tightened better and being stabbed in the hand with a socket is merely unpleasant, whereas stabbing your hand with an antifreeze coated screwdriver is frigin painful.

[The Moog]

Top tip tightening jubilee clips with a socket and never a screwdriver, you can get them tightened better and being stabbed in the hand with a socket is merely unpleasant, whereas stabbing your hand with an antifreeze coated screwdriver is frigin painful.

Man doth speaketh wisdom

[The Reverend Bluejeans]

Smear LM grease on inside of hose, do hose clip of moderately tight, job done.