Switching from Kenlowe to traditional fan

[DickBrowne]

It’s not been a great week in the garage, a host of new parts has resulted in more leaks than I started with…

One of the more annoying of these is a constant drip from the top radiator hose, which I suspect is down to the temperature probe connector not allowing a perfect seal - I’ve swapped the hose for a nice new one, added a second clip, and still the drip is there.

It may seem a bit overly dramatic, but I don’t really need the kenlowe fan, and I think an original will suffice, so in order to preserve what little of my sanity is left, and to actually move a step forwards, I am thinking of swapping back to a trad fan and remove the electric one entirely. I’ve replaced the radiator, the thermostat and all of the hoses so the cooling system is in good condition, plus the wiring and everything for the Kenlowe is contributing to a generally busy and untidy under bonnet area, so a swap could be a good thing…

I think the drip was a historic thing, as there was a small piece of silicone rubber in the old top hose when I removed it, which I’m now guessing was to help effect a seal around the sensor, but can I find it? What do you think!

Downsides? A new fan is around £30, which I don’t want to pay, so a good secondhand one would be good enough.

Am I being daft? Will I regret it? Do you have an old fan suitable for a 1967 car which you’d be willing to sell for a reasonable price?

All thoughts, recommendations, remedies and folk-lore gratefully received. Please convince me that I’m wrong and I just need to do ‘X’ to remedy my drip, or give me then confidence that I’m doing the right thing.

[Ian F]

Dick, the belt driven fan on my 72 has always been perfectly adequate. This is especially true if you have an oil cooler fitted (I do). The only potential downside as far as I'm concerned is that the belt driven fan takes a small amount of BHP to drive it.
Given the number of folk who have fitted thermostatic electric fans, it should be easy to source a traditional one from one of the s/h dealers.

Ian F

[Tom Ward]

The small piece of silicone rubber is a standard Kenlowe part which would have come with the kit. You can buy a replacement from Holden Classic. It is designed to act as a seal for the thermostat bulb to enter the top hose. It appears in your case it’s not doing the intended job.

https://www.holden.co.uk/p/kenlowe_seal

I’m in the process of doing the opposite to you and have sourced a second hand kenlowe. I’d have suggested a swap with you but I’ve already bought all I need and mine is the later plastic fan.

In the main, the standard cooling system on the mgb is perfectly good enough for day to day use. Unless you find yourself regularly sitting in traffic on a daily commute or you plan to do something more dynamic like auto testing or rally tests then, with a well setup, clean system which it sounds like you have, then you are likely to be fine.

[Bumpa]

The extra bit of rubber around the Kenlowe sensor was supplied with the kit to effect a good seal - it's not a bodge. You could fit a Revotec thermostat where you cut the top hose and install it there - like this https://www.burtonpower.com/revotec-ele ... gcEALw_wcB They do them in lots of sizes. I have one on my V8 - the only criticism I have is that the on and off points are too wide apart. It is adjustable with a small screwdriver under the cap.

If you are buying a used metal blade fan be aware that they can suffer stress fractures, and if a blade breaks free it will likely slice the radiator or top hose as it departs. Look very carefully for cracks.

[Peter Cresswell]

The MGB only needs a fan when it is running in slow traffic and idling for long periods. On the open road it is fine and so long as the radiator is in good condition this also applies to very hot sunny weather. I would consider doing away with the sensor and and wiring the fan via a switch on the dashboard. I suspect you keep an eye on the temperature gauge anyway, so it is simple to just switch it on when the temp starts to get to 90 deg or so. The pressurised system prevents the coolant from boiling until about 110deg.
If you do go over to a metal fan, I would suggest the fitting of Fan Shroud, These considerably improve the air flow through the radiator and will just about contain the temperature to below 100 deg when in heavy traffic or stationary. I fitted one for a trip to France and after many miles on the Autoroute running at 75/80mph, we hit a 'French' traffic jam and the temperature didn't go above 90 deg with an ambient temperature of 35 deg. Very impressive. As far as I know these are only available from Moss.

[DickBrowne]

Thank you for the replies everyone.

The cooling system is mostly new, so I’ve decided that the standard fan is the way to go - I have one in the post and on it’s way. It’s in primer so I need to spray it, and that’s another question - colour! I also restore vintage mowers and stationary engines, and the rule there is anything which could hurt you is painted red to denote ranger, but the block on my MG is also painted red and, at the risk of being branded “a bit of a tart”, I’d like to avoid clashing colours under the bonnet.

So what was the standard colour? Does anybody know? I don’t want to paint it black, as that’ll be all but invisible which could be dangerous. I’m thinking yellow could be a good choice

[Ian F]

Bright yellow as far as I know! Moss sell a bright yellow engine paint which I think is correct (available from others no doubt......).
Ian F

[Bumpa]

I agree - bright yellow.

[Geoff Norcliffe]

Hello Dick,
About 3 -4 years ago I renewed the whole cooling system on my 67 BGT and decided to smarten up the fan with new yellow paint. I used Hammerite smooth. Surprisingly after leaving the fan to dry for 48 hours before re assembly I found after the first use that tiny flecks of yellow paint had sprayed over the area around the fan. Clearly it had not dried enough to cope with spinning around at normal engine speeds. Could be a good idea to dry off the fan somewhere warm before use.

Geoff

[DickBrowne]

Hi Geoff

I do find that Hammerite takes an absolute age to dry, but you’d have thought that 48 hours would have done it?

Anyway, the new fan arrived today, it’s a three blade one and looks really solid. Once it’s sprayed it’ll look nicely original I think.

I managed to, finally, sort the steering today - it was a combination of alignment, lubrication (although I did overfill the rack and had to cut the ties on the gaiters to drain some out) and, ironically, the grease nipple on the U/J catching on its opposite part.

Once the fan arrived, I thought I’d test-fit it, which finally involved stripping the alternator out, the radiator and hoses off and, oh joy, giving really good access to the bolts on the steering rack, which would have been handy when that needed adjusting!

Job for tomorrow, after I get back from Bicester Heritage (it’s a Scramblers Sunday) is to buy some yellow paint, get the fan sorted and start rebuilding the cooling system. Again.

Still, it was a lovely day today, I had the garage doors open and everything. Hopefully tomorrow will be similarly gentle and enjoyable.