Fan Help

[sirstude]

I now have the radiator in the Olds, and looks like I got things too close sometime during the changes.  Anyway, I have 15" diagonal from the left top corner to the top of the compressor pulley.  That pulley is 1 inch out from the radiator.  The alternator and the water pump pulleys have 2 inches from the radiator.  I can fit a 14" fan in the top left corner.  A 16" would be under the compressor pulley by about an inch, but I cannot find one thin enough on the end to fit.  The radiator core is 22" tall by 21" wide.

The radiator is one of US Radiator's super cooler with triple flow, and the say it will cool 800 hp, of which, I MIGHT be close to half of.  8.2 compression, mild cam 454, so should not build too much heat.  I am only worried about slow cruising.

Anyway, I am think about adding a pusher in the lower passenger side of the radiator, probably a 14" also, so that the entire front of the radiator is not blocked off with the fan.  I have had issues with pusher fans blocking enough air flow that the car overheats going down the freeway.  My Studebaker used to run 160 down the road, but hot in parades, and after I installed a big pusher, overheated on the highway, but was fine in town.  I finally built a shroud for it, and that cured the issue.  No room for a shoud on the olds.

Questions:

1. Do you think I need a pusher in addition to a 14" puller
2. Anyone know of a 16" high flow fan with the outside edge less than 1"
3. If I use a pusher, should I sandwitch it between the radiator and the condensor, or should I set the condensor 1/2" out from the radiator and then put the fan outside of that


Turbo 400 switch pitch trans, so I have a B&M super cooler trans cooler, that I plan to mount horizontally under the outside of the body.  Anyone see any issues with that, since turbo 400 don't build much heat.

The last picture is from Sunday, I got the compressors mounted under the rear of the fenders and then got the fenders mounted.

Thanks
Doug

[Crosley.In.AZ]

typically a puller fan is better from what I read,  as the only fan used.  

A pusher fan should be an auxillary  to a mechanical fan.

[WZ JUNK]

I would only use a puller as I have not had much luck with pushers.

The picture may be misleading but it looks like you might have room for a smaller diameter but high cfm fan near the top.  I do not recommend mounting a fan to the radiator.  I only use a fan in a shroud. These shrouds can be only a inch or so deep.  The shroud forces the fan to drawn air through the whole core of the radiator rather than just the area where the fan is located.  It is important to seal the shroud to the radiator core around the edges.  Air flow is like water and it will seek its easiest path.  You will loose a lot of cooling ability if the fan is sucking in and recirculating hot air from the engine compartment rather than through the core.  It is also important to seal the top of the core support to the hood to prevent hot air from being recirulating back in front of the radiator.    I make my own shrouds out of fiberglass to fit the radiator.  The process is usually pretty simple.  I use a wood or foam blank the size of the radiator core and lay up a glass shroud.  That last statement is somewhat a simplified version of the process but it is the general idea.

I should have pictures of shop made shrouds.  

John

[kb426]

I will ad my 2 cents worth: I was told a pusher isn't an effective as a puller. An electric fan that can be manually turned on before the temp rises is a good thing. I used a Centec electric controller that has an override switch. Anytime I'm in "parade mode' I turn the fan on before the regular temp controlled start begins. This has worked for me. I had to remove the mech. fan for reasons similar to what you describe. I bought a Cooling Components fan and shroud. I have no problems yet. This is after 14,000 miles. My thought about this is that if you can control the heat buildup before it's a problem, that can be an asset. This is my humble opinion, not to be confused with anything good.  

[kb426]

Holy cow! 3 of us agree on something!

[enjenjo]

I had one a while back that was a similar situation. I ended up installing two smaller puller fans, I believe they were 11", and OE Ford parts, down low near the crank, and a 15" pusher high on the front outside the AC condensor. That one was a Spal. Two fan circuits, one for the pullers controlled by a temp switch, and the 15"pusher was on another circuit, also on a temp switch, but set higher, with an over ride to run it whenever the AC was on.

[sirstude]

Thanks guys, I know a pusher is not a good deal, but the top left corner is all I have, and at that, the outside 4 inches or so of the fan have to be less than 2" thick to clear the pulleys.  Not like me to mess up so bad on the clearance.  The pictures are deceiving in that it looks like more room than there is.  From the top of the core to the top of the alternator pulley is 10", to the top of the water pump pully 12" and to the top of the air conditioning pulley is 8.5".  If I measure diagonally from the top left to the edge of the compressor pulley, I have almost 15", so that is where the 14" fan comes from.  I might have to try making a buck and see what it looks like.

I did figure on the pusher as an additional fan, not the primary.  

John, Do you cut holes in the back of the shroud and then cover them with a rubber flap on the engine side so the extra air can go through when running down the road.  I also did figure on sealing the radiator opening at the top so all air runs though the radiator.  Big openings at the back of the engine compartment from the factory, and I am not messing with them.

I am looking for a high flow low edge height (remember the 2" clearance to the pulleys) 14" fan if anyone has any specific experience on one.  No one within 300 miles of me stocks any electric fans, other that some factory replacement ones.  Jegs has a Proform that says it has 1650 cfm.  I can't translate the Spal 14" VA08-AP70/LL-23MA , but it looks like it would fit physically.

Thanks
Doug

[wayne petty]

443 options to examine..

http://www.summitracing.com/search/Department/Cooling-Heating/Section/Fans/Part-Type/Fans-Electric/?Ns=Rank%7cAsc&RC=100

you will want to run at minimum an 8 gauge power wire to the dual relays..  if one burns out the other still works..

most of the dual fans take around 25 amps of power in pairs.

i know that you have probably calculated a 120 to 140 amp alternator.. with a 6 gauge wire to the battery.. so the alternator can keep up with the electric fans.. fuel pumps, ignition. wipers, AC and blower motor???

[sirstude]

John,

What kind of foam are you using for a form.  I haven't played with fiberglass since I was a kid, but I know it used to dissolve foam when the resin hit it.

I think I found a fan that will work, and figure there is just enough room for the shroud.

Doug

[wayne petty]

working in fiberglass..  hmm.. the big boat... 108 foot at the deck and 21 foot beam.. all covered in fiberglass..

but what you are looking for.. is something to protect the cheep sheet foam you are going to use as a plug..

can you find some   PVA exterior paint..   not PVC..  or a combo of the two..   that is what a local entertainer used to coat the styrofoam he uses before he sprays krylon spray paint on it..

same sort of effect you are going to need to stop the epoxy or which ever resin you are going to use..

so.. the foam..  PVA paint..  

there was another post offsite about using conventional wall plaster to fill gouges and mistakes..   you could actually use that to build up your foam and smooth it out..

....................

if you cut it in wood.. or some other slightly tougher material...  you also have the ability to send your pattern off to a Vacuum forming shop...   have them vacuum thermal form several for you.. so you can work one..   and if you make a slight mistake..  you can use the second to carefully create a perfect one..

i would imagine that several layers of PVA over a finished foam plug might work with the thermal vacuum forming..

these are just ideas.. as its been a LONG long time since i worked with fiberglass..    and that boat took at least a pair of 55 gallon drums of resin..  worst part.. all the workers loaded the bronze rope guides  in their stuff and carried them off for scrap..  they got most of the power tools also.

[34ford]

polyurethane foam to use for a buck (resin melts polystyrene)


this site gives some insite into glassing over foam. click at the bottom of the page to go to the next page


http://project33.com/Categoryarticle.cfm?ID=578&Category=Interior


bob

[sirstude]

Thanks for the polyurethane foam tip.  I remember reading that a long time ago.  The chances of finding any here in Helena, are pretty small, but I will look next week.  

Another posibility, does anyone know if Saran Wrap is fiberglass resistant.  I could carve a plug out of high density insulating foam board (the blue or pink stuff) and then wrap it with Saran Wrap and coat that with mold release.  Lay the fiberglass up on top and then rip the foam out of it after it cures.  I am only looking for a one use mold.

Thanks
Doug

[kb426]

One of my friends used to use wax paper all the time. I personally haven't used it but he did alot of glass work. There are several builds on Dotheton.com that have detailed instructions. It might be worth your time to check some out.

[34ford]

Thanks for the polyurethane foam tip.  I remember reading that a long time ago.  The chances of finding any here in Helena, are pretty small, but I will look next week.  

Another posibility, does anyone know if Saran Wrap is fiberglass resistant.  I could carve a plug out of high density insulating foam board (the blue or pink stuff) and then wrap it with Saran Wrap and coat that with mold release.  Lay the fiberglass up on top and then rip the foam out of it after it cures.  I am only looking for a one use mold.

Thanks
Doug

I built some molds for my armrest and covered them with masking tape and that works ok. So will duct tape.  Here's a pretty detailed article of building a one.

http://www.crankshaftcoalition.com/wiki/Make_a_fiberglass_fan_shroud

[sirstude]

Thanks for the help. I did more research on the RC boards and they use a process they call "lost foam".  What they do is build the form out of insulating foam and then cover it in packing tape.  Wax the tape and then lay up the fiberglass over the top.  Then then cover the fiberglass with 100% dacron that they call Peel Ply (This is the "poor mans gel coat").  Take a piece of the dacron cloth and lay it over the last ply. Work the resin/epoxy up through the dacron cloth exactly like working the resin/epoxy through the fiberglass cloth. Don't add any extra resin/epoxy. Smooth the dacron cloth with a squeegee working the excess resin/epoxy out to the edges and off the work piece. Note how smooth the surface is, this is good. Look for any imperfections, bubbles, areas that are not wet out completely, they will be very visible.  AFter everything has cured, they pour acetone into the foam which dissolves it.  Then they remove the packing tape from the fiberglass and there you are.  

I will be giving this a try in the next couple of weeks.

Doug