Having a problem with cooling if anyone has any suggestions....Fan kicks in and out when standing and driven at normal speed, but when driven hard or at a constent high speed it stays on continuosly and the fan struggles to keep the temperature under control so i have to stop! I was thinking about putting louvers and holes in the top of the bonnet but i have noticed not everybody does this and i don't really want to hack my bonnet if this isn't the problem! i'm running a triumph spitfire 1500 with a cortina radiator and 15" fan with an adjustable fan switch and no heater , any ideas would be great
Cant say I can help with your prob.
But you defo dont need to cut holes
I run a 2.0 Pinto with a Polo rad.
I did a run dayb4 yesterday 22deg all day.
Round trip 200 miles, only time the fan came on was when i got home an was putting the car away.
Fan switches in at about 105deg.
Is your fan a sucker or blower.
Sometimes having the fan infront of the rad blocks the natural coolmng.
I have a 2.0 pinto on a micra rad, so your cortina rad should keep the spit unit rrreally coool.
Have you checked for obstructions, airlocks etc, have the vanes on your water pump corroded away?
I cut vents in my bonnet to keep it cool when stuck in traffic, but made no difference at all so don't bother.
One thing which can make a truly massive difference, particularly when on the move is if you have the air ducted to the rad so it can' t escape or "leak" round the rad sides - same goes for the fan on the other side, if it can draw air other than thro' the rad you'll waste tons of cooling effect. One further thin is that the hot air needs to be able to escape somewhere & it will want to rise rather than go down beneath the car, so you may need some louvres, but would defo try the ducting/sealing solution first.
Fan is a sucker type and i've just fitted a new water pump. I was going to up grade to a polo rad and exspansion tank but not sure if this would make much difference!
Russbost, i have about 25mm gap around my radiator would this make a massive difference?
Simples problem is down to ignition timing being way to retarded - Check the centrifugal advance is working (also very sparingly lubricated the
mechanism and twist the shaft clockwise and counter clockwise a few times) ) , gap the points to 0.015" and set the ignition timing
properly.
With things like this you have learn to see the wood from the trees, and not jump to the conclusion it is a radiator or air flow or water flow issue.
If the ignition is too retarded you get a massive increase in the heat energy rejected to the cooling system and exhaust system especially as the
crankshaft speed increases.
[Edited on 23/4/10 by britishtrident]
quote:
Originally posted by russbost
One thing which can make a truly massive difference, particularly when on the move is if you have the air ducted to the rad so it can' t escape or "leak" round the rad sides - same goes for the fan on the other side, if it can draw air other than thro' the rad you'll waste tons of cooling effect. One further thin is that the hot air needs to be able to escape somewhere & it will want to rise rather than go down beneath the car, so you may need some louvres, but would defo try the ducting/sealing solution first.
Batho, I would say a 25mm gap is certainly enough to make a significant difference, particularly at higher speeds - whether it's enough to cure your prob ...............????
Bit late in but......
unless the rad is badly blocked (possible?) or severe airlocks, then it should easily cool a spitfire. In fact the fan shouldn't be needed at all
when moving.......
As above the problem is bound to be with the engine tuning, so check that first.