I’ll leave aside the pros and cons of auxiliary fans. I got mine because I wanted the peace of mind of knowing that I could sit in the queue for the Goodwood Revival, and wouldn’t have to watch the temperature gauge climbing to max, and wonder what revs at idle achieved the best trade-off between airflow and heat generation. Fitting the 13” Kenlowe in pusher configuration certainly seemed to help with that.
The problem with this fan (and with others) is that they come with plastic ties to fix them through the vanes of the radiator. This is a horrible idea, running the risk of rubbing a hole in the radiator pipework over time and, more significantly for me, meaning a very difficult job to cut the ties when wanting to remove the radiator. There is no room to get the rad out with the aux fan still attached, especially if you want to keep the original fan impeller and shroud in place. The radiator place I used recently confirmed that they had come across many occasions when the plastic ties had caused leaks.
You need a bracket, but which one will fit, and how do you attach it to the car? I’ve had success with the fan brackets and straps designed for SPAL fans, available from T7 Design for £10 each (https://www.t7design.co.uk/products/rad ... p-kit.html). You have to get 4 brackets and straps. They have to be cut and bent to shape. The brackets are a good fit into the T-shaped slots on the Kenlowe, and can be secured by drilling through the bracket and its slot and inserting a screw or split pin. For the attachment to the car I used stainless steel rivet nuts. These inserts create a threaded insert in the bodywork. Drill a hole of the right size, and then use a tool to mount the rivnut and fix it in place – same principle as a pop rivet, but unfortunately you have to use a special rivet nut tool. I’ve found the Tacklife tool excellent, very solidly made and much more useful for various car restoration tasks than I expected. £50-ish. Imagine for example not having to hold a nut steady inside the wheel arch while fastening a bolt from inside the engine bay! https://www.amazon.co.uk/dp/B073WXFP34? ... E_DDE_dt_1.
The only other thing to think about is the seal between the fan and the radiator. Pusher fans are apparently less efficient than pullers, so getting them close the rad is important. You can bend the SPAL straps to bring the fan close to rad, but it is also helpful to fit a closed cell adhesive backed strip around the edge of the fan (6mm thick neoprene sponge/foam). This improves the seal but also prevents any danger of the fan vibrating against the rad. Here’s a link to a suitable strip https://www.ebay.co.uk/itm/121388027214.
The result is a super-solid fan installation, independent of the rad. Took a little while to fit (2 or 3 hours), but cost less than a rad rebuild. See photos below.
Ps. This whole job started when I decided to replace the Kenlowe variable temperature fan controller with a unit from Revotec. The Kenlowe version has a capillary pipe going into the top hose – another terrible idea, causing endless leaks. The Revotec controller requires you to cut the top hose and insert the temperature switch unit into it – a bit clunky but effective. A word of warning – the wires from the Revotec unit are a bit short, only just reaching the inner wing on the other side of the engine bay. Don’t be tempted to rewire it – very easy terminally to blow up the unit, as I found to my cost.
