Which cooling system?
Turbo Mini Forums

I'm looking at how to plumb everything up at the moment and am looking for your thoughts.

I'm using a 2 core side mount rad and late model 2 speed heater. I've not really studied these heaters in the MPI cars to know how they are plumbed in but it looks like both hoses pass through the bulkhead on the passenger side with an internal mounted heater control valve.

I was going to to use an early lower rad hose with the single heater return, however while digging through my stuff, i found a 92 cooper rad and bottom hose which has the take off to run to a sandwich plate (which I also still have from the head from the same car). My thoughts are now turning to using of this set up (lower hose) as opposed to the earlier style.

I suppose it comes down to what benefit there would be in running a system with a takeoff in the sandwich plate

your thoughts?

If you use the sandwich take off to supply the heater rather than the port above number 4, the coolant is forced to flow across the block and then all the way back across the head. rather than going through the block and then a fair amount of coolant going up into the heater take off.

if the engine has had the dry deck mod then this would be best, but if its the standard configuration wouldnt the heater take off in the normal position above number 4 cylinder help encourage flow around the hotter end of the block?
obviously this is just my theory from lots of reading,

one day boost will be mine!

the set up still has the take off (heater feed at no4. the bottom rad hose has the return but it has a second connection which feeds from the sandwich plate aswell

the second connection on the bottom hose is for the expansion tank.

On the mutro and later minis the heater is fed by the sandwich plate and returned into the bottom hose.

hmmmm,

this could be why my heaters shit!

Andy, I'm not so sure; the hose is pretty much as it came off the car; one hose clearly goes to the sandwich plate and the other still has the heater valve attached to it

Yes i moved to the darkside

Instagram @jdm_brett

Been messing with Spi engines at work lately, heater takeoff comes from the sandwich plate, via a heater valve, through the heater and then back into the bottom hose. Personally I'm sticking with the heater takeoff on the cylinder head as it promotes better coolant flow around cylinder 4 from what I have read.

i'm completely confused now; the car this all came out of was a 92 carb model cooper. The bottom hose I have is marked 29 on this somerford catalogue
http://www.somerfordmini.co.uk/pdfs/Catalo...20Radiators.pdf

I'll take some photos when i can but i'm now a bit lost as to what i've got

the other takeoff is for the manifold on that bottom hose

doesnt matter

Edited by Carlzilla on 11th Feb, 2012.

In my opinion, the plumbing will depend on whether you use the original head to pump bypass or not.

So, I'm guessing you'll be running a carb, Are you running a bypass hose as Colin mentioned?
I've drawn up what I personally think is the setup best to use, welcome to opinions on this.
If you dont have a bypass hose, I'd drill a few small holes around the outer ring of the thermostat to allow at least some coolant flow until the stat opens.
Very quick crap drawing, but hopefully this makes sense:

Edited by Carlzilla on 11th Feb, 2012.

joe - i wast starting to think about that,

colin, i'm not intending to run a bypass hose

carl, yes carbed turbo is the intention

I wish i could remember how it all looked before i ripped it out the donor car! All I can go on is shapes and positions of hoses

Edited by Rob Gavin on 11th Feb, 2012.

I'm wondering where the otherside of the manifold connection goes!

http://www.somerfordmini.co.uk/pdfs/Catalo...20Radiators.pdf
in this link hose 28 is for the carb model. which only has the usual 1 connection for the return from the heater

in this link http://www.somerfordmini.co.uk/pdfs/Catalo...20Cables%20.pdf it shows the other end of the manifold connection on the injection set up, going into the heater hose inlet after the valve.

one day boost will be mine!

I think the simplest way of heating the inlet manifold, using my diagram is simply take the heater outlet off the head straight to the inlet, then back out of the inlet to the hose going to the heater valve.
I have no idea why Rover didn't do that in the first place rather than piss about doing what they did with the sandwich plate :S

My old engine, the heater takeoff on the left of the head, across the front of the rocker cover, back towards the heater valve sat behind the right hand side of the rocker cover, through bulkhead to heater, back from heater through bulkhead to bottom hose. And you'd simply place the inlet in the middle of the section running in front of the rocker cover. Although i never bothered and i couldnt get mine up to temperature using an 88 deg stat, a standard new rad, and that system. I could be caining it up the motorway, screaming the nuts off the engine, then pull off at a junction and stop, and only then would it briefly get up to 90 degrees, then quickly cool down after the junction.

Edited by Carlzilla on 11th Feb, 2012.

without the bypass, your best bet is to use the sandwich plate to feed hot water to the heater AND the bottom hose VIA the inlet manifold. There is the Cooper RSP bottom hose that has two connections on it, similar to the SPi bottom hose.

If you use the bypass hose or at the very least drill a few holes in the thermostat plate, there is a hose specifically for taking hot water from the old heater take off at No4 cylinder end, throught the manifold, and back into the bottom hose mentioned above, with the heater feed from the sandwich plate.

Either way you do it you need some flow over the thermostat for it to operate efficiently, with holes in the thermostat the least desireable

Forgot to mention my setup used a bypass hose above.

ok, I've been back up to the workshop and had another look at what i have - not quite how I originally saw it.

The bottom hose has the twin pipes but the one i thought went to the sandwich plate looks like it actually goes to the heated manifold.

so as i see it, if i adopt this set up, one of he hoses (the one with the heatervalve) will go through the bulkhead and connect to the heater; the second hose, which used to connect to the no4 outlet via the heated manifold will now connect direct to the no4 takeoff (i'm not using the heated manifold); the connection from the bypass hose will go directly to the heater.

cheers for all your help

rob

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Are you feeding the heater from the sandwich plate and returning into the bottom hose?

thats my understanding from this set-up i've got. The takeoff from no4 will feed back into the bottom hose as well

Looking at the picture above, that is a Cooper RSP or Mainstream hose set and configuration.

Why not heating the inlet manifold?