cooling fan

[rt green]

have to put a radiator in my 77 b200 custom van. i just got the radiator, and tommorow i have to pick up hoses and such. this thing is a 318, and no air. it came with this tiny 4 blade fan, which i suppose it worked, but i have a 7 blade fan off a 440 laying around. it will fit. will i loose horsepower at  rpm on the freeway from this fan? they are direct drive fans{both, no clutch}. i htought that it would draw more air through, but then thought the engine would be fighting the incoming air at speed. it's a bitch to install, well, not really that bad,but i don't want to do this twice, as i work on cars all day at my job, and i really dont feel like continuing it at home.  except for the charger.      thoughts?         bruce

[dodge freak]

Where do you live or drive the van ? If its down south or out in AZ I would switch fans. Up in Ohio or farer north maybe not, but this summer it was over a 100 degrees a few days even in ND.

The rad. was old and clog, the new one should work fine with either fan. Those fans do take alot of power to turn at high rpm's which it most likely does not see.

If you do swap fans do it with the rad. out but you know that right.

[rt green]

live in south dakota. its been hotter than hell this year. have to pull a small trailer to minnesota, back home for a vintage motocross race. caring 2 old dirt bikes and some gear.  probably be about 300 miles one way.  gas, i know, but got to try and have some this year.  the race is in sept. hope it'll be cooler this year. do you recomend i try the bid fan, or stay whith the small one?

[dodge freak]

Well summer is over for SD I would think so the small one should be fine. As for next summer who knows, what you hit 115 i think not so long ago. You know what you could do , is just keep the small fan on and if it starts running hot next summer get a electric fan up in front of the rad. to pull some fresh air in to the rad. Thats what I would do. With 115 I am not sure even the big fan alone would be enough. Electric fans are under $100 and work great.

[rt green]

food for thought. i soppose the thing got by for almost 30 years or so on the small one.what state are you from? hotter than here i bet.   bruce

[dodge freak]

Heck no I am by Detroit MI , Yes it was fine for 30 years that why I said keep the small one, no point in spinning a bigger fan and burning more gas than you have too. It is still warm but I think the 100's are over with for you, we be Lucky to hit 90 again, the hottest we got was 98 this year.

Don't get rid of that fan and go all electric you need at least two nice ones, just get a ok electric up in front if needed later on. The new rad. is going to make a big difference.

[firefighter3931]

Bruce, try using the original fan and swap it out if there are any issues. The new rad should do wonders for the operating temps. Generally speaking, fans are only needed when the vehicle is stationary (idleing in traffic) and once the truck is out on the open road the air hitting the rad at cruise speed is more than sufficient. The factory clutch fans were designed around this premise....engaged at low engine speeds then released at higher engine speeds.

Basicly, if it doesn't overheat at idle (small fan) it won't overheat out on the open road.  


Ron

[rt green]

thanks dodge freak and firefighter. maybe i'll get some sleep tonight not haveing to roll the question over and over in my head.  oh, i'll still have the rt to worry about.

[dodge freak]

WTF - just check out the temps. everywhere-SD is 98 degrees, wow I had no idea how hot it still is there. It hit 82 degrees here by Detroit. Hope everything is working ok for you.