Water Pump on 16/70

[keithjecks]

My '36 16/70 seems to over heat whenever it gets to a long hill. Normally it runs at about 80 deg, but on a long hill it goes to 100. Every time you park the car it dumps some coolant and if you don't top it up the over heating gets worse. All seems to be working (i.e. water circulates etc) and the fan belt is tensiones correctly.
   
   Two questions: First, there is a knurled wheel at the top of the water pump with what looks like 'increase' and a clockwise arrow marked on it. Does this increse the flow through the radiator? It looks like a bypass valve.
   
   Secondly, on the induction side of the pump is something that looks like an oversized metal tyre valve cap. What is that? If you remove it, it has a lot of gunge inside. Is this suppoesed to be full of grease? If so what type? Does it matter?

[1936ACE]

If it's anything like on my '36 Ace, the knurled knob is on the top of a brass thermostat housing.  Unlike modern thermostats this is a butterfly valve attached to a bimetallic spring, the idea being to restrict water supply to the radiator when the water is cool.  On mine the valve (which is simply a circular disc) had been removed many years ago - presumably because it didn't work properly.  Try removing the disc to see if this solves your problem.
   
   Until last year I was trying to persevere with the original water pump - mine was the version with a 3 blade cast aluminium fan which looked as if it came from one of the boatyards in Thames Ditton.  Biggest problem was keeping the grease separate from the water.  I gave up in the end and fitted a new one from Robin Woolmer.  That's fine, but now I'm having the radiator rebuilt as it is rather incontinent.  It's all good fun isn't it!

[keithjecks]

It actually is good fun I think (so long as I don't end up cooking the engine and needing to rebuild it!) It is so different to my othyer Ace, where any problems are fixed by plugiing in a laptop. It is so nice to have large bits you can get to and get a spanner to.
   
   If it is just the thermostat it probably won't help much, because the problems happen when the car is hot, of course. I will try removing it anyway to see if it is stuck.
   
   Mine also has the rather nautical cast fan. The water pump is now starting to make a groaning noise when cold so I suspect I am in for trouble there. Am I right in recalling that the pump bearings are prone to failure on these things? Maybe I should put a new pump from Robin on the jobs list for the Winter?

[administrator]

I have a RW pump on my 16/70.  The old one was so moth eaten it was not repairable.  It's early days yet (~600 miles) but Robin's pump seems to be very well designed and made - and doesn't leak at all!

[1936ACE]

If you get one of Robin's pumps you will also need to get/make a new fan because there won't be enough space to use the ship's propeller.  I also fitted a new slim-line electric fan for which there's just enough clearance between the front of the radiator core and the slats.  You can get one from s-v-c.co.uk.  Currently it's simply wired to a switch on the dash, but with the rebuilt rad I'll have a thermostatic switch as well.

[keithjecks]

Mike - I am now trying to get to grips with the cooling issue once and for all (see new topic on the subject). To save me the possibility of getting it wrong, what fan did you use, and how did you fit it? Also, someone mentioned to me (was it Robin) that they had fitted an electric water pump as well, with a timer. This enables you to keep the water circulating for a couple of minutes after the car is stopped so that the car doesn't then boil over. Does anyone have any idea how to fit this, and what pump to use?
   
   It seems from people's comments that cooling is always a bit marginal, but I would like to be able to use my car next year reliably in warm parts of France so would like to deal with this once and for all.

[Robin A Woolmer]

'www.thinkauto.com'sell two types of electric water pumps one for high flow requirements & a small one for auxillary flow which would probably do what you require. You would need to think about the pipework as i doubt if the small flow type could be fitted in series!
   I am sure Thinkautomotive can offer some tips on fitting.
   By the way have you power flushed the engine & Radiator?
   
   Regards
   
   Robin

[1936ACE]

Hi Keith, My car will be back on the road for the next Barley Mow meeting, but regretably we're run out of time for Goodwood.  I will be happy to meet up to show you what I've done.  If you're buying an electric fan make sure you buy a 'pusher'.  It comes with an assortment of fitting brackets and I was able to make up a 3 point fixing - two horizontal and one at the base where there's a flange that sticks out at a right angle over the starting handle assembly.  The kit included fixings that pass through the radiator core, but the man who built my new radiator warned me against using these.
   
   If you're intending to use the car in VSCC events, as I hope you will, they don't mind electric fans but take exception to electric water pumps (and alternators, but that's another story).