D.I.Y. Cooling Improvements

[wixer]

Uprated the fans on my 500 a couple of weeks ago, only problem was, they kept blowing the 40amp fuse. So, being lucky enough to work in the car industry, I have a wealth of people and knowledge on hand to question, to resolve my problem. Within two minutes of talking to an electrical engineer, he came up with a very simple additional circuit design, that basically just plugs into the cars existing wiring and allows the use of two 30amp fuses, one per fan. The existing 40amp fuse in the fusebox being replaced by a 3amp. The entire additional wiring loom, consisted of two inline blade type fuse holders, one 70amp relay, connectors to mate upto the existing cars fan connectors and obviously some wire. I was luck enough to get some samples but all the components required could quite easily be bought from any motor factors for less than a tenner. The only additional connections that needed to be made, were a direct power feed through the relay, to the fans and an earth. On the back of my fusebox are two unused main power feeds, so one of them was used and I earthed the main power supply to the redundant fixing hole on the intake manifold. It has the same size fixing as one of the fuel rail bolts. Once the source for the power was found, this installation was a piece of p**s. Am thinking of going directly to the battery positive terminal, to try and reduce the voltage drop and subsequent drop in revs when the fans first kick in. The system has been on trial in my car now for over two weeks with no problems. It worked a treat at Mania the other week and we know how hot it was then. And as an additional tip, the new Jag XJ uses 40amp blade fuses, so, anyone finding it a little tricky to find any, pay a visit to your local Jag dealer.

[big col]

Cheers Phil
Am going to try it at the weekend

g

[andy43]

Sounds like the 'sample' bearings that I happened to 'acquire' at work a couple of months ago. Theres a lot of these 'samples' about...

[schimg]

Phil

Thanks for the providing an informative thread!

Did it to the Chim yesterday, stuck in loads of traffic today ...no problems.

It's nice to know that there are people out there that are willing to solve problems and then once established, pass these workable solutions on to the rest of us.

Once again cheers.

Steve.

[shpub]

TVR did something similar when the 40 AMP fuse problem occurred and the later cars have a seperate relay and supply for each fan. It also sounds very much like the Mod-Wise mod kit for the 40 AMP fuses.

Steve

[wixer]

Probably is similar to the Mod Wise kit but I find it far more satisfying when you've solved the problem yourself and it's obviously cheaper aswell.