Suzuki Club UK

You want it to pull the air in, otherwise it's not keeping the air flowing over the engine!

camelbend123 wrote:I put the fan onto push as I figured it would dispell the hot air out rather than trying to cool through puling through, is this a flawed assumption?!

The mesh is actually pretty wide if you look at it and needs to be there for protection really. I only do low speed trialling so flow of air in the front isn't something to worry about to be honest.

Did you put the fan on the opposite side of the radiator or reverse it electrically. It would need to be on the outside as fans are the only efficient in one direction.

I still think you would be surprised how much airflow that mesh would stop. I've got a Samurai grille with big open slots and the bottom ⅓ of my radiator on show beneath the grille and never picked up any damage so I think a wider mesh would still provide adequate protection.

I guess with it drawing air out even at slow speed the combination of the mesh restriction and the air pushing onto it from forward motion will neutralise the airflow over the rad. Add to that the fact the restricted amount of air you are putting over it has already been heated in the engine bay and it sounds like a recipie for overheating.

If you only drive at low speed and presumably higher than average RPM its even more reason to have lots of airflow.

For the sake of trying it I would remove the mesh and fit the fan to suck coldoutside air over the radiator just to see.

I always run fans the way zook123 suggests, suck the cold air in through the rad. That way there is nothing to block the front if the fan isn't on

I'm with Dan. I think your problem is stagnant air in the engine bay is being recirculated around and around and around. Bear in mind that hot air rises - which is why SJ's have vents in the bonnet at the back. Your vehicle then sucks in this hot air as you don't seem to have a snorkel, and raises the internal temp of the engine even more.
I can't see your bonnet in any of your pics, so perhaps I'm talking out of my arse, but I get the feeling that you've created a nice little hotbox for your engine, with nowhere for the hot air to go. It doesn't want to go down and out below your vehicle until the vehicle speeds get higher and air pressures get higher, but even then some of it will create a pocket of hot air without vents at the top at the back (hence SJ vents being top/back...)

Try running a backwards bonnet scoop with the fan pulling air in, over the engine, back towards the scoop. That'll keep mud out but allow the air to flow in a natural path out of the engine bay. Running your fan backwards is going to be a bad idea since the airflow when moving forwards will make a cushion ahead of your vehicle, like a hovercraft - keeping the air in the bay nice and hot as it recirculates. Maybe add a cold air intake/snorkel too, so that your engine is burning with nice cold air - but make sure your placement of the cold air intake makes sense, a lot of them are placed next to the exhaust manifold, and then people wonder why their car gets worse temps and worse performance.

Running a rad in the back can work, but often has the same problem with recirculating hot air because the back of a vehicle is an air "dead zone". Usually that only happens at 15mph plus though.

Have a watch of this video for a "ghetto" mod for rear radiators to get rid of that problem:


Click Here for Youtube Video

I had problems with the M13A in my Jimny last week, I topped up the coolant in the rad and ran it until the thermostat opened and burped some air out. I haven't had a problem since and have done 500 miles.

All good suggestions, I see your point on the fan now so I'll reverse that the way it was supposed to go.

I do agree with your point about the hot engine bay, I was thinking of a scoop myself, however when I ran it up last week I left the bonnet open and it still got hot....!

It did seem to be running with relatively high revs, there's no counter but I would suggest c1300rpm, even though the throttle screw was wound right back, is this a symptom at all?

Thanks for all your help, much appreciated!

Have you considered some louvres in the bonnet? while a scoop will force outside air in when you are moving, mostly off roading isnt a quick sport! just some plain vents might allow the air to escape more easily

If you run it from cold, does it get up to temperature quickly, I only ask as my Jimny gets up to temp after 20mins of running on the driveway, the gauge sits around 90degrees.

What AntiFreeze are you running, as my old Corsa used to get hot rather quickly when only using water?

Update on the post....

Figured head gasket had to be the problem apart from the fan the wrong way!.. so put in steel seal, and crossed fingers...

Sadly started her up today and the temp just kept climbing as before. It takes about 20 minutes on tickover to get to 110 with the bonnet open.

Thinking of getting a donor engine and swap them out, annoying I can't figure it out though!

Any other ideas? I don't particularly want the hassle of an engine transplant especially as I don't have a garage yet!