Cabrio V8 cooling

[slatept]

Hi My newly acquired Cabrio has a V8 engine fitted. Just sorting a few things out before I get it MOT'd. At the moment it has the Marlin supplied radiater, which seems a little small, although I am toying with the idea of getting a custom made aluminium radiator made up.
The car has an electric fan at the front of the rad and a cooling fan at the rear driven from the engine pulleys. Space is very tight between the engine fan and the radiator and the hoses etc in this area. I'm thinking as I have the electric fan do I really need the engine fan as well. I wondered what other Marlins with V8 engines have.

[listerjp2]

Re: Cabrio V8 cooling

Although I am a Roadster owner, my old school mechanic gave me some good advice some years ago.

I had removed my fan and just relied on the electric fan and had problems with overheating.

He suggested that, as the under bonnet room was at a premium, the original fan was helping to dissipate the heat.

I put the fan back on and have not had an overheating issue since.

The long and short of it, I would leave it on.

No doubt, others will have other ideas but this has worked for me on both my Toyota powered engine and my current Marina 1.3 based.

Regards

Adrian

[greyV8pete]

Re: Cabrio V8 cooling

Sounds about right. I read on a Landy off road forum that the mechanical fan contributed to engine cooling due to the constant flow of air over the alloy block and heads. Those guys tend to fit twin electric fans with a cut out switch for when they drive through 4ft deep puddles to save filling the engine compartment! So they loose the benefit of the mechanical fan.

[slatept]

Re: Cabrio V8 cooling

Sounds like I need to leave it on thanks all.

[dave_kitson]

Re: Cabrio V8 cooling

Hi - I am amazed that there is space for the fan behind the radiator. The build manual says to remove it, and cut off the nose of the shaft. There is then only a small gap to the radiator. Do you have a smaller radiator which is set further forward, I wonder? It is generally believed that a fan works better by sucking rather than blowing, ie better behind the radiator. With that in mind I looked at fitting electric fans behind my radiator, but it was impossible. So I remain with a front mounted fan and an assortment of other devices to keep the temperature down. The Rover V8 is well known for running rather warm, so if yours is behaving, LEAVE WELL ALONE!!! Enjoy your car! Dave.

[slatept]

Re: Cabrio V8 cooling

The radiator is squeezed between the nose cone and the up rights on the chassis with no spare room. It misses everything obviously but it looks like the mechanical fan has had problems in the past. Most of the radiator cooling elements have been flattened but luckily its still watertight. I'll see how it goes I may get a new aluminium radiator made up.

[lizbillings]

Re: Cabrio V8 cooling

Suggest you get it MOT'd and try it. Just the weather for runs out now.
Liz

[stewart 27]

Re: Cabrio V8 cooling

it coud be the size off the rad i have one that you can come and mesure

[droverpete]

Re: Cabrio V8 cooling

It misses everything obviously but it looks like the mechanical fan has had problems in the past. Most of the radiator cooling elements have been flattened but luckily its still watertight.

If the radiator is damaged can the air still get through it?
You may be surprised how far an engine can move forwards, distorting the mounts, under heavy braking.

[kahawi]

Re: Cabrio V8 cooling

If the fins have been flattened, it will limit the flow, for sure. One of the ‘tasks’ when servicing customers air-con was to ‘comb’ the fins to improve air-flow through.

[listerjp2]

Re: Cabrio V8 cooling

Sorry for my ignorance, but what is Combing?

If the fins have been flattened, it will limit the flow, for sure. One of the ‘tasks’ when servicing customers air-con was to ‘comb’ the fins to improve air-flow through.

[greyV8pete]

Re: Cabrio V8 cooling

Sorry for my ignorance, but what is Combing?

You use something like this to re-align the fins

https://www.toolstoday.co.uk/sealey-radiator-fin-straightener?gclid=EAIaIQobChMI5oKSoKSK8QIV04BQBh2lAQuuEAQYAyABEgKmzPD_BwE

However car radiators tend to use a pack core with wiggly W shaped fins so I don’t think this tool would be any use for that. I have always very carefully used a small thin blade screwdriver to tease the fins straight. I carefully use a vacuum cleaner crevice tool to remove dead flies and a hose to wash dirt out from back to front. High pressure to be avoided or you will damage the fins and have to return to go!

[listerjp2]

Re: Cabrio V8 cooling

Ahhh, light bulb moment.

Every day is a school day.

Thanks for this.

Adrian

[kahawi]

Re: Cabrio V8 cooling

Being a clever bugger, I borrowed my Brother-in-Laws pressure washer and blasted years of muck out of my Citroën ally radiator, it looked pristine and immediately leaked like a sieve, totally ruined it, where those 'years of muck' were hiding massive salt-induced corrosion!