15 replies to this topic

[charliedurrant]

Hi,

I have recently fitted a metro 1275 (I'm very new to this so bare with me) to my mini. I recently posted about a lip around the output from the head to the heater valve.

http://www.theminifo...l=&fromsearch=1

Well after searching around I now realise that the hole has been drilled as the metro did not have a heater output at that point. The heater valve was clogged and thus no water was passing when open or closed. I have freed up the valve and cleaned it with citric acid.

I understand the metro did not have a bypass hose and the common thing to do is to

"Drill 1 or more holes in the thermostat"

I have a number of questions I hope there are answers to:

1) I have no idea what radiator I have, here is a picture of the inside - I assume it is 3 core as there are 3 rows or channels inside?

 what-core-radiator.jpg   79.19K   18 downloads



2) Is the radiator I have suitable for the 1275 with a piper fast road cam and a mildly ported head?



3) If I was to drill hole(s) in the themostat to allow the heater to be shut off in the absence of the bypass hose how many should I drill? There are opinions ranging from drilling many small to one large hole

Minispares

http://www.minispare...ty=pb&pid=35425

It is possible to run thermostats with the troublesome by pass hose blanked off by drilling 4-6 holes 1/8" in size around the priphery of the thermostat.

TheMiniForum

http://www.theminifo...showtopic=94584 A range of answers

Personally I think 'less' larger holes are better as there would be less issues with clogging?



4) If I were to drill the holes, where should I drill them?

Just checking really, they can really only go aound the ourside disc as you can't really drill anywhere else.



5) As an alternative to drilling holes or having to leave my heater valve open all the time what are people's thoughts on using the sandwich plate as used in the metro

http://www.minispare...ty=pb&pid=33405

 sandwich plate.jpg   7.37K   1 downloads

I have a minispares ally inlet which I could then run the water out of the sandwich plate though the inlet manifold and then T piece it to the outlet from the heater.

http://www.minispare...id=35083&title=

 minispares-inlet.jpg   5.88K   0 downloads

This would allow me to retain my heater on / off and the engine will heat us as usual. What are people's thoughts on this route?




Thanks in advance

Charlie

[charliedurrant]

sorry to bump....

Charlie

[charliedurrant]

This is a very popular forum so bumping again...

Charlie

[charliedurrant]

bumping the most exciting topic on theminiforum

[freshairmini]

I have the sandwich plate fitted on mine as standard and it's fine. Mine is a RSP cooper which uses the mg metro engine as standard.

I've always thought drilling the stat is a bit of a bodge. So my vote is for the sandwich plate always best to use the proper parts for the job. Then you know it will work best.

[charliedurrant]

So you have a pipe from the sandwich plate which then runs to...... I know it is a big ask but if you fancy popping the bonnet and taking a photo? I assume it runs back to the heater outlet?

[bmcecosse]

Forget the sandwich plate - just put 2 X 1/8" holes in the rim of the stat - and don't run hot water through the inlet manifold.......

[charliedurrant]

Bmc,

I was hoping for a reply from yourself as I know you have posted on this before. Minispares said not to bother with the sandwich plate and drill 8 holes hence my confusion. Like fresh air said I dont like to bodge things either but the holes are a very common fix.

The only other alternative I thought was to fit an inline heater valve and t off there back to the heater output....

I have heard that there is a possibility of hotspots without flow around cylinder 4 which the bypass hose allows - am I being a big girls blouse?

Charlie

[Sprocket]

don't run hot water through the inlet manifold.......

Why ever not?

[minimanclive]

The MG Metro, and the carb Cooper both used the water heated inlet manifold. I remember seeing the 1275 Maestro had the inlet manifold plumbed into the coolant circuit as well. I figure if it's good enough for the factory that's how i'd plumb it on mine.

I'm using the sandwich plate, and an inline heater valve to the heater, and the bottom radiator hose from an SPi Mini.

[charliedurrant]

Minimanclive,

You have exacly what I was thinking! Any photos would be amazing to see.

Charlie

[charliedurrant]

Okay, I have my choices with waht to do with my cooling without a bypass hose. The right thing to do and the tight thing to do (1, 2,3, or 8 holes in the thermostat I don't know)......

So the only rad question left....

How does one tell how many cores are in a rad? And is the rad suitable with my setup longterm?

Charlie

[stuwhitfield]

I've been running my metro lump with drilled stat for 2 years with no cooling issues to date (touch wood).

The extra plumbing for a sandwich plate costs a fortune compared to std parts (unless you bodge it with t pieces)

[charliedurrant]

bump

How does one tell how many cores are in a rad? Picture attached to first post....

Charlie

[charliedurrant]

p.s. link to photo of an inline heater valve

http://www.theminifo...ttach_id=118645