9 replies to this topic

[minitaz80]

Hi there, I'm new to the mini forum but not to Mini's. I've hit a bit of a confused state with the installation of a metro front rad in the mini and could do with some help.

 

The pic of the installation is here:

 

https://www.facebook...36&l=8a6378a103 (also attached in case you can't see it)

 

If you can see the comments on the photo on Facebook, it is suggesting I connect the expansion tank lower pipe to the bottom hose, could someone confirm this? If it is correct, I can do away with the sandwich plate, unless I'm mistaken?

 

Many thanks in advance.

 

Dan

Attached Files

•  2014-09-04 22.11.42.jpg   86.7K   64 downloads

[ibrooks]

That's a true mongrel of a system. Did it actually keep it cool or has it not run in anger yet?

 

 

The Metro had the sandwich plate to feed the heater instead of the tap at the clutch end of the head - you've got both. Why?

 

The heater tap should provide coolant to the heater matrix and then return to the bottom pipe - you've just got it linked to the top pipe so it's not going to do anything useful. If anything it will reduce the flow of coolant through the head and may cause problems.

 

On the Metro the expansion tank did connect to the bottom hose with the bleed takeoff on the stat housing also connected to the expansion tank's neck (but still on the pressure side of the seal).

 

On the Metro the sandwich plate replaced the heater tap and also the bypass hose as it fed the radiator but it was also below the thermostat so it allowed a flow of coolant through the heater matrix before the stat opened (the Metro's matrix was in the engine bay so it didn't matter that it was always warm). That pre-flow is necessary so you need to make allowance for it if you are running a Metro head & pump with no bypass hose. You do have the stat between the sandwich plate and the stat housing and not between the head and the sandwich plate don't you?

 

It's difficult to tell from the angle of the photo but is the expansion tank actually higher than the stat housing?

 

Personally I'd suggest you go with either a Mini system with the expansion tank added to account for the loss of expansion space and filler cap in the radiator OR the Metro system. Not some mish-mash of the two.

 

Iain

[Vipernoir]

With the heater tap takeoff plumbed in like that, you are risking stalling the waterflow across the head.
Even if it doesn't, your cooling across the middle cylinders will be compromised.

 

The expansion tank is connected wrong.

[Guess-Works.com]

Yeah, the pipe from the heater take off to the top hose is going to cause all sorts of problems as you're bypassing the thermostat... I'd blank that off, or take it back round to the bottom hose, where the heater return would normally connect into.

I assume the radiator is off a K series metro rather an A series

 

The expansion tank needs to be plumbed into the bottom hose and not the heater take off, and if you've not got a heater, then blank that off

[Turbo Nick]

pipe from the heater take off goes back into the top hose if you're not running a heater, helps to keep cylinder 4 cool.

 

bottom of the header tank goes into the bottom hose.

 

Yup, ditch the sandwich plate.

 

That's how mines been run for years with a front radiator, no cooling issues at all.

Edited by Turbo Nick, 08 September 2014 - 05:35 PM.

[Vipernoir]

Taking hot water from the heater takeoff on the end of the head and dumping it straight back into the bottom hose without cooling it will make the engine run hotter.
If you do have to run a hose following the route of the original heater hoses, you need to plumb in an auxilliary rad (heater core) in the airflow to have any benefit at all.  Not doing so is actually detrimental.

[Turbo Nick]

No need for an extra core, just put the heater take off back into the top hose and let it go through the nice big front radiator. 

[Vipernoir]

No.

 

Hot goes to cold - plumb the heater takeoff into the top hose and you will be injecting hot water into the end of the head.

[Ethel]

I don't think you will, the water pump is the prime mover of coolant and it draws water into the impeller from the bottom hose. At worst one of your cylinder head outlets could stall if the other can handle the pump's flow demands all on it's own. The only issue I see with Nick's setup is long warm up times with so much radiator flow bypassing the thermostat.

 

The simplest way to sort that system would be to put a "T" in the sandwich plate to header tank hose and connect the new branch into the bottom hose.

 

You could muck around with some flow restrictions to fine tune the various flows to get the best balance of cooling and warm up times. all you need is a bit of copper pipe in the flow line to  crimp .

[skoughi]

I've plumbed in an mg metro rad into my clubman but I've still used the heater takeoff for the heater but fitted a t junction onto the pipe with a flow restriction leading through the alloy inlet manifold then out the other side and then into the bottom hose. The flow of water always will go to the heater first and if the heater flow is closed then it will overcome the restriction and flow through the alloy manifold thus hopefully providing a bypass going from no4 cylinder as my head im intending to use has no bypass. There is a bleed pipe coming off the pipe coming out of the manifold and another coming from the top side of the thermostat, both these go to the expansion tank which is plumbed into the bottom hose. I just hope it all works as I've tried to keep it as simple as I can!