Homemade Fan Shroud (2 Viewers)

[guzzla]

I haven't run a fan shroud for a number of years and never noticed any real difference in operating temps - even comparing temps to my mates 80s that has a shroud fitted and we both run the same temp gauges fitted in the same place. At worst, mine has been 2-3deg more on rare occasions, mainly driving up hill, but this is more due to my turbo charger

But I digress... with the addition of the auto trans and having just replaced the viscous fan clutch having found it to be well past it's use by date, I figured I should pull my finger out and fit a shroud so, if there really is any benefit of extra cooling with a shroud fitted, my engine, AC and gearbox wont be disadvantaged. The genuine fan shroud I purchased didn't fit and, after cutting pieces out of it to make it fit around other stuff before realising it didn't fit, it was too late to return it

After a quick look, I decided I'd make one out of fiberglass. Now, my experience with fiberglass is amateurish at best, but of the things I have made, they have been more than adequate for their application and the finished product didn't look to shabby. While this was by far my biggest mission working with fiberglass, I was confident I'd get a good result - With a bit of forward planning and lateral thinking. Let the fun begin...

Something that I've been meaning to do for a long time is drop the rad down 25mm after the body lift that went in several years ago. I did this by drilling 2 new holes in each lower mounting bracket. For the upper mounts, I cut them out oversize and welded in a new section of 2mm plate. I then marked the new holes and drilled them out with a hole saw. All up, it took about 2hrs. This was followed by a trip to the radiator repair shop to have it inspected and cleaned. I really didn't think it needed cleaning and, when I went to pick it up, the repair guy echoed my thoughts. Anyway, for $150, it was cheap peace of mind knowing 100% it was good as new. He also suggested I keep using the Toyota red coolant and he said it's the best coolant for that engine.


With the rad in position, I taped up an area where the fan spins. Using a square, I marked in several locations where the fan blade edges projected forward.


The fan measures 470mm across and the OEM fan shroud opening measures 500mm... that give 15mm clearance. Using some 12mm ply, I cut out a 500mm diameter circle. The OEM fan also sits 100mm off the face of the rad core so, I cut 4 blocks out of 90x45 pine and screwed them to the underside of the ply circle. Then, using the marks on the masking tape, I placed additional marks 15mm further (to give me 500mm over all) Once I'd positioned the plywood into place, I held in in place with a hot glue gun.


Sitting the radiator on a sheet of ply, and using some speaker cloth (purchased from JayCar Electronics) I stretched the material over the rad to give me a nice, tight fit. I held each side down with a timber batten screwed to the ply. I've used this speaker cloth before with fiberglass projects and it can be made to fit virtually any shape or profile, and it can be stretched super tight without fear of tearing.


Next, I needed to make up profiles and clamps to further control the profile I needed the shroud to take. I did this using a series of timber battens, Alloy angle, steel plate and even bricks to keep it in position.


Once I knew everything fitted, I removed it all and set it aside. I then mixed up some fiberglass resin and painted it onto the speaker cloth. Once it was soaking in resin, I then reinstalled all my battens, clamps and supports.


Left to dry overnight, I then removed all the bracing to leave me with a nicely formed fan shroud template.

 

[guzzla]

Next it was time to start fiber-glassing. I wanted to get a couple of layer on before fully removing the shroud from the radiator to minimise any distortion or damage. This also meant that it would fit neatly back into position. On tip with fiber-glassing is to make sure you have everything ready before you start mixing the resin. While you can vary the gelling time, you still only have 20-30min before it's useless - and that time can go very quickly with fiddly jobs like this.

For this project I used 225gsm glass strand mat. It works well on these projects as the resin soaks into the mat and the Mat can be formed around almost any shape. Just paint the frame with a generous coat of resin, sit the mat on top and paint more resin over making sure to work it in. Ensure each piece of mat overlaps the other. Once the required amount of matting is installed, I roll the whole job with a steel roller. I'll post a pic later, but it's basically a 3in long threaded rod secured on the ends by a formed wire handle. Using this tool helps to remove any air bubbles, gives a more even coverage of the resin and flattens out any irregularities you might have.


Once dry, I was able to remove the shroud from the radiator. You need to take your time here to prevent distortion or damage. I used a steel rule to help separate the mold. A good trick, and one I forgot to do in my haste to get the project underway, is to apply a couple of coats of wax to the areas you don't want the resin to bond to. Cooking spray also works but leaves a sticky residue finish. You can see I've begun marking where I can trim it back and also the mounting points. For the areas I need to reinforce or make bigger, I've stuck more tape on the back to support the next few layers of fiberglass.


After applying 2 more layers of mat and a few extra bits in places I wanted to reinforce, I then made a lower section to fill in the bottom of the shroud. Again, using a few pieces of timber and some tape, I had a template ready to glass up. Note I didn't forget the wax this time.


After 4 layers of glass, this is it ready for removal and trimming. Don't be afraid to make things a little bigger than needed - it's much easier to trim it back than extend it.


After applying a few more layers of fiberglass to the shroud and a bit more trimming, I sat the shroud into position, placed the lower infill section in place, taped up the outside edge to keep the resin in place, and then glassed up the inside to bond it all together.


With a bit more trimming done, it was time for a test fit. Trying to get it all in reminded me why I might have not bothered fitting the last one. Never the less, it fits first go and I'm pretty happy with the way it's tuned out - even if it isn't finished yet


Next, I'll remove it all to give it the finishing touches and a coat of color. Stay tuned

 

[kdxman]

Very cool I did not even know that could be done.

 

[jamisobe]

That is very cool and well done.

Why did you make one rather than buy one from a bone yard? Fiberglass is a PITA to work with. The OEM shroud should be better than adequate and shouldn't cost much more than the materials to make one?

 

[timer00]

I just took my 80 up to VT/NH for 1400 or so miles with no fan shroud since it broke trying to get it out for the crank/oil pump cover seal job.

It was in the 80's the whole time during the day up there and took long day drips up and down mountains/hills.

I got 190 at the highest normally and 200 was my highest on sustained steep hills with the revs up there (this happened only twice the whole trip on the same long mountainous hill) So yes the fan shroud probably doesn't matter too much though I will still get my replacement soon.

o yea I use green antifreeze

 

[inkpot]

That is very cool and well done.

Why did you make one rather than buy one from a bone yard? Fiberglass is a PITA to work with. The OEM shroud should be better than adequate and shouldn't cost much more than the materials to make one?

Quite the project. I read the first post as "installed genuine fan shroud" as meaning an OEM. I am sure curious why it did not fit up right. Maybe due to his turbocharger? I have done several radiator jobs on 80's recently, and the shroud was a good fit on all of them. John

 

[doc W]

Very nice piece of work. Hope the effort pays off in cool running this summer.

 

[badmuthatrucka]

Man, that is a pretty sweet shroud! Now I need to start playing with fiberglass...

 

[diego355]

Nice job, I need one

 

[guzzla]

Sorry guys, totally forgot to update this and finish it off.

To answer earlier Q's, I made this after trying to fit a genuine fan shroud that didn't fit as it should. Since I'd already cut it in places here and there to fit around a few other bits, thinking it was going to fit at the time, I couldn't take it back. So that was $200 down the drain. While I have an aftermarket radiator with shroud mounting points is slightly different locations, Whith the fan in the correct location, it sat way off centre to the fan blades. Checking on Toyodiy confirmed I had the right shroud, so I'm stuffed if I know what the issue was. Anyway, this turned out to be a lot of fun.

Once I confirmed it fitted just right and drilled all the mounting holes, I put some thick foam around the radiator so the shroud could form a nice seal around the edges. It was sourced from the local hardware store and only cost a few dollars.


Here it is sitting in position to confirm everything fits perfectly. I wanted a durable, hard wearing finish. To achieve this, I added some black tint to a batch of fibreglass resin and painted on one thick coat. Once dry, I was left with a rock hard, gloss black finish.


And, finally, here it is in all it's crappy picture quality glory. Fits like a glove.


After a recent 10,000km Outback Australia trip, taking in some very hot climates, I can report that it performed flautlessly. Infact, in the really hot weather, my engine temp sat, on average, 8degC cooler than the 2 other cruisers I was travelling with. To say I'm wrapped with the result is an understatement. When people see it in person, they can't believe how good it looks - almost factory.

 

[wrongway around]

really nice work i love the speaker mesh form. many years ago i bought a airstream bus that i converted to a handicap hillbilly rv. i wanted to remove the boxy front roof section to original slooped tapered shape. i tried the alluminium angles with bad results .then my dad said why not make it out of fiberglass . hmmm. but how do you form it ? well being a boat builder he had a couple tricks up his sleeve ,and said easy just use cardboard .so i rivited the cardboard to the perimiter then wet the cardboard with a water spray bottle molded it to shape ,then let it dry .then simply soaked the cardboard with fiberglass resin and taperred the edges with glass . the area was 5 feet by 3 feet .worked out perfect strong as crap .had that rig leak free for better than 10 years of rough camping service. point being that anything that has some type of mesh patern that will obsorb resin will work with great results .

 

[Elbert]

nice job.... looks like it came from the factory that way.

Do the fan blades site entirely inside the shroud? Or is a portion of the fan blade exposed...at the rear of the shroud...

 

[guzzla]

nice job.... looks like it came from the factory that way.

Do the fan blades site entirely inside the shroud? Or is a portion of the fan blade exposed...at the rear of the shroud...

The back of the fan blades are basically flush with the outer edge of the shroud. I made it a fraction deeper than the OEM Toyota shroud that didn't fit properly for some unknown reason. But I do need to cut the shroud back a little so it's easier to get out - 10mm should do it.

 

[Rockets2000]

After weeks of debating how I was going to fab up a fan shroud, I finally found something that will give me the results I want. Well done and thanks for posting this!!!!

 

[MoeGasim]

great idea....having issues here with the amount of heat in summer...and shrouds are very rarely available in the local market

 

[math]

great idea....having issues here with the amount of heat in summer...and shrouds are very rarely available in the local market

Let's just be real here - I've read your entire thread, and not one post has ever said something like "I needed this part, so I went out and bought it". I don't think ANYTHING is available in your local market Seriously, I think you've made every single part of that truck by hand. Definitely one of the coolest projects on this board.

 

[Dave 2000]

Not taking anything away from the job as IMO it looks great, I hate fibreglass and cannot recall anything I have made from it looked that good but, I ran most of a year including summer here in Spain without a shroud and my temps did not hardly alter at all. I do have the temp gauge mod which makes the gauge more sensitive so I was not being fooled by the dumbed down gauge, this added more impetus to my electric fan mod.

I honestly feel the 80 cooling system in stock form is way over specced, apart from the engine dragging around the weight of the car in all sorts of temps and conditions and not having (in most countries) an electric 'booster' for the A/C condenser, add to this it also has a very good towing limit to cope with, I think no shroud is needed and just takes up space under the bonnet.

Still, I think it must have been a very satisfy project.

regards

Dave

 

[MoeGasim]

Let's just be real here - I've read your entire thread, and not one post has ever said something like "I needed this part, so I went out and bought it". I don't think ANYTHING is available in your local market Seriously, I think you've made every single part of that truck by hand. Definitely one of the coolest projects on this board.

thank you .... but...i did buy the diesel....couldnt have made that myself...

 

[NCFJ]

WOW killer job!!!! I make my own shrouds for the Vortec swaps I do but I am a Tin Man. I have done my share of glass work on bpoats in the past but have no where near the skills you do.

Here is the latest tin shroud

 

[Dave 2000]

I had a great welder once, shame I was sodding crap at using it! some great fabrication there.

regards

Dave