Aftermarket Aluminium Radiator Core/Shroud/Fan

[Banjo]

Some time back, in the following thread  https://www.rollaclub.com/board/topic/73676-oil-pump-failure/page/9/#comment-714036  I described how I fitted a Toyota Echo radiator core/shroud/fan to my KE30.  It has been very very successful, & with the removal  altogether of the fan belt driven fan; certainly released energy to the wheels, rather than to be constantly turning the fan blades; whether it was needed or not. It indeed confirmed that; on an indicator I placed on the dash, which illuminated, when the electric fan was operating; that the "ram effect", of air through the radiator, was enough to adequately cool the engine, except, when you pulled up in traffic, at lights, on a hot day.   In fact there have been days, when I've been out on the road, & the electric fan has never activated, until a few minutes after I arrive home, & the "heat soak" out of the engine, pushes up the coolant temp.  The electric fan will typically run on for 2-3 minutes, & then turn off.  (typical of what you hear walking around shopping center car parks)  By the way, I live in Qld. not Tassie !

There was however, one draw back, using the Toyota Echo radiator/shroud/electric fan setup, I fitted.  The outlet on the bottom of the Echo radiator, was on the wrong side, & the S.S. tube pipe I fitted, runs across the face of the crankshaft pulley, where I need to fit my new aluminium trigger wheel, to test my new Speeduino ignition system, on the road.

On ebay, I recently came across KE30 Aluminium core/shroud & fan assemblies, c/w relay & thermostat switch, for around $ 240-$260 ea., which seemed a bit cheap to me.

     

Has anyone purchased & used one these radiator core/shroud/fan setups; & were they any good ?  Previously, You would barely be able to purchase an "aluminium core only", for that sort of money.  I am just concerned about the quality of the product.

If anyone gives them the "thumbs up", it will be a simple fix, to allow me to fit the Speeduino finally to the car, & do some road testing, rather than the test bed engine stand, without a dummy load device, which Altezzaclub & I have as yet; not been able to come up with a cheap water pump engine load etc idea !

Cheers Banjo

 

 

Edited March 3 by Banjo

[Banjo]

I have just realised I have another small issue, with fitting the EFI trigger wheel & Hall sensor/s, to my K series engine, as well as the return pipe from the bottom of the Echo radiator, passing in front of the crankshaft pulley.

At present, the Hall Effect dual sensor, is mounted on a metal bracket I fabricated, which mounts on the LHS of the engine block, where the Rollas with A.C. mounted the compressor. 

As I intend to fit a compressor & AC system, eventually, then I will need these mounting points.

Quite by accident, I came across this photo, of a beautifully prepared K Series Toyota engine.

My eye caught sight of a very neat bracket attached to the camshaft sprocket casing.  How Neat !  Would certainly overcome my problem.

It looks so well made, that maybe someone, somewhere, in the world produced one on these at some time. I looks like it is maybe just an aluminium disk screwed to the front of the existing case.  I might just have to investigate that a bit . . . . .

Has anyone ever come across one of these specials before ?

P.S.  I note the beautiful engine above, has an A.C. fitted; although it might actually be an external oil pump, tooth belt driven ?

Anyway, I found a 5K Camshaft sprocket cover in my shed;  cleaned it up & measured it up, this afternoon.  I know the casing, is not dead flat across the front. About 2-3mm proud in the centre.  I found a stock aluminium disk 120mm in diameter, & 4mm thick on ebay, in NSW, so will be here in a couple of days.

It shouldn't be too hard, to grind the curve off the front of the casing, & attach the disk, to give it lots of meat, & strength, as I need a very stable & rigid platform, to attach the Hall Effect sensor to.

Cheers Banjo

Edited March 4 by Banjo

[coln72]

am I missing something or is that a pump for the dry sump set up.0

[Banjo]

Looks very much like it to me, Col.  Unfortunately, it was the only photo I could find on the net of that particular engine.  Some photos of the six sides of the engine, would provide all the answers.

I do have a 5K engine I bought a few years ago, for $ 100. It apparently, had been used in a speedway midget, & would rev to almost 11K.   Was really worked over, & one day, I'll put it all together.

It does have a couple of odd outlets on the sump, which indicates, it might have been used in a dry sump application, as no matter, how many baffles you place in the sump; in a speedway application, the oil is constantly thrown to the side of the sump.

However, I did find a photo on Rollaclub, in a post dating back to 2008, which depicts a TRD alloy dry sump, for a K Series engine.

Cheers Banjo

 

 

Edited March 4 by Banjo

[coln72]

I know all about oil getting flung to one side of the motor..... 

 

[Banjo]

That photo I came across; of a beautiful K Series motor preparation, (see earlier post in this thread) has had my mind racing this week.

Although the "specialised camshaft sprocket aluminium cover", looks like it is professionally made; I couldn't help but think, that I want one !  So if you can't buy one; could I just make one. I really need all the space in front of the engine, so a bracket that holds the Hall Effect sensor; vertically facing down to the edge of the trigger wheel; would provide the best solution. 

My "lash up", to prove my concept of a "no missing teeth trigger wheel", using rare earth magnets, with a separate single inboard magnet to create the crankshaft positional signal. 

  

However, since then, I've purchased a Haltech double Hall Effect sensor, where the sensor barrel, contains two Hall Effect devices. One detects North pole magnets, & the other detects South pole magnets.  Being the same housing means there only needs to be one row of magnets around the aluminium disk edge.

I have 35 magnets around the edge, with south pole facing the sensor, & one magnet, with the north pole facing out.  This then produces the same result as a 36:1 toothed wheel, from the "South Pole" Hall Effect device.  However, the single pulse per revolution, positional sensor signal, can be "OR'd" with the 35 pulses, to produce a very accurate signal, with no missing tooth gaps, for determining high accuracy & resolution, for extremely accurate RPM measurement.  Accurate RPM info is most important, as it determines where on the MAP, the ECU takes its preset response curve.  The picture directly above, shows two Hall Effect devices, & the single positional indicator magnet is located inboard, in line where the missing tooth is located.  The single Hall Effect sensor I'm now using simplifies this above depicted arrangement. I now have a single Hall Effect sensor with two Hall effect sensors therein.  This allows a single row of sensors around the outside of the aluminium trigger disk. 35 off magnets, with "south"  pole facing out, & one off magnet with it's north pole facing out. It all works, & I have had the engine actually running like this, in full sequential firing, via the Toyota Echo COPs, I've mounted on the engine; albeit, with only fixed advance of 10-12 degrees.

However, the Haltech Dual Hall effect sensor, is longer than the two (2) off single output Hall effect devices depicted above.  It looks like this . . . . . 

 

That means, the Haltech sensor sticks out horizontally, even further.  So my intent is to mount it vertically, off the camshaft sprocket aluminium cover.

I've dug out an olde 5K cover, & ground the slight dome off the front of it's external face, so I can mount the 6mm x 120mm thick aluminium disk, which should arrive in a couple of days.

It won't look as good as that professional one, depicted on the web photo, earlier in this thread; but it will provide me with a solid & firm base to mount the sensor, as vibration from brackets sticking out in open air, provide a source, to create missed sensor signals, where air gaps are small, & missing positional signals, are not welcome.

However, solving one problem, introduces another consideration !  The mounting of the sensor vertically, requires that the rare earth magnet end faces, also meet the Hall Effect sensor face vertically.  This is because the magnetic field is stronger; close to the "poles", where it is concentrated.

This will require embedding the magnets in "the edge" of the aluminium disk.  The face of the Hall Effect sensor is 10mm in diameter.  Obviously, that would require a very thick aluminium disk.  I've settled for some 4mm rare earth magnets, I have here, & have ordered a 200mm dia. x 8mm thick aluminium disk, to embed them in.  The magnets will be 20mm long.  The problem is that mounting the magnets in that fashion, exposes them to the centrifugal force of the spinning disk, trying to "shed them" .  This does not happen presently, as the magnets are contained securely from centrifugal forces, as they are pressed in from the side of the disk. My technique previously, was to drill the holes in the disk, slightly undersize; & press the magnets in, using a vice. I'll use that technique again, & fill the hole with Araldite, before fitting them. Then laying the disk on it's side, on a hard flat surface, A simple centre punch to the side of the disk, in the middle of where each magnet is embedded; should result in no movement in magnets at all.

However, I have seen pictures of professional Aluminium trigger wheels with magnets, so went looking at what others have done.

Holley / MSD produce something like this . . . 

In this case, the magnet face is pointing to the side of the disk, rather than facing the sensor. The answer to this query, is actually in the photo.  The sensor only has two (2) wires coming out of it.  It is in fact; not a Hall Effect sensor, but a common VR, or variable Reluctance sensor, which requires no power.  It is interesting, because the picture of the K Series engine above is also using a single VR sensor, & a ferrous "missing tooth" trigger wheel.

I do not favour the VR sensors; although I know manufacturers in the USA & elsewhere, have used them for decades. My objections are two fold. 

One, the waveform from the VR sensor is a badly formed sinusoidal waveform, & requires extra electronics to "square" it up, so the time information is accurate.

Two, "the amplitude" of the waveform, is quite low, at low revolutions; (whilst cranking), & therefore, the very time at which you are trying to start the engine, on a cold Winters morning; the sensor is providing it's lowest amplitude.

So when I receive a 200mm dia. x 8mm thick aluminium disc, this coming week, I can then work out, how I'm going to set it up, to drill 36 off 4mm holes, 20mm deep, around the narrow, (8mm) wide edge.

P.S.  One of the nice & convenient things about my little project; is that I can pop the original dissy in; remove the COPs, & run the engine, whilst lining everything up on the trigger wheel, & checking the Hall Effect sensor outputs on the CRO.

Cheers Banjo

 

 

Edited March 11 by Banjo

[altezzaclub]

That shroud covers a lot of the radiator area, I wonder how it affects air flow itself.  Great for sitting at the lights with the fan running, not so good for passive airflow hauling up hills.  I suppose robotic welding is now cheaper than some Chinese girl welding it by hand, so the price stays down.  Maybe you don't need the shroud at all.

We've just fitted a double pass crossflow radiator and fan to the Evo5 tarmac car, no shroud, and to my horror, no way to mount the fan except with 4 zipties through the core. Seems that's acceptable these days, and with the tanks vertical at the sides there was the flimsiest bit of alloy channel top and bottom. Josh welded pins on so it drops into the Evo rubber mounts at the bottom and is clamped down at the top. That system is a vast improvement over bolting rads to the front wall.

What size & shape are the magnets? Drill them into the circumference from the side and tack a ring of aluminium over them to hold them in? 200mm diam, say a metre of 0.5mm thick by 8mm wide alloy strap.  Even a ring of alloy wire.

 

[Banjo]

My KE30 already has a Toyota Echo radiator in it, with electric fan, which I fitted several years ago.  Here's a a comparison photo I took, comparing original & donor Echo radiator, at the time.

The Echo radiator, total area is similar, but it's aluminium; & more efficient. The Echo radiator fan covers a much greater area, of the honeycomb, than the aftermarket Chinese one. It also has insulated mounts top & bottom, so I don't use, at all;  the original body mounting points on the side of the original KE30 radiator mounts.

It works really well.  The only reason, I want to replace it, is that the bottom outlet, is on the  wrong side, for the K Series engine, & will foul my trigger wheel, attached to the crankshaft pulley. I might just take the Echo radiator to my radiator repair guy; & get him to move the outlet to the other side, & blank off the original outlet.  I'll follow that idea up, next week. 

The rare earth magnets are cylindrical in shape; 4mm dia x 20mm long.  The end must to face the Hall Effect device. The interference fit into the hole, plus some Araldite, plus a centre punch dimple on the side of the disk, should make them very secure.

P.S.  I agree with you about the common use of regular zip-ties, to connect the aftermarket fan assemblies to the core. Both my engine test beds have aftermarket electric fans, mounted that way, with zip ties. However, they are "stationary motors"; not bumping along roads, creating vibrations.

Cheers Banjo

 

 

 

Edited March 9 by Banjo

[Banjo]

Pressing the rare earth magnets in through holes on the side of the aluminium disk, prevents the possibility of the magnet being "shed from the disk"; by the centifrugal action of the disk spinning at several thousand RPM.  However, that requires the Hall Effect sensor to be pointing to the side of the trigger disk; rather than the outer edge, of the disc; where it it should ideally be, for my application.

Well, I might have just found the answer.  A bit of research, unearthed a rare earth magnet, in a "diameterical" configuration, where the magnetic fields ( N & S) are concentrated on the "cylindrical sides", rather than at the ends. 

 

 

 

 

 

 

 

 

 

This would allow the rare earth magnet, to be pressed into the side of the disk, around the periferal, & close to the edge, with either the N or S pole facing the outwards. It may be, that they don't need to be pressed into the disc, if I can source them, with a countersunk hole in the centre.  They could then be simply bolted to the aluminium disk, with a brass countersunk screw & nut.

Better still, these rare earth magnets, are available, here in Australia, & come in an N42 strength format, which provides a much greater magnetic field strength, than the N35 ones, that are more commonly available; & which I am currently using.  More strength, allows greater air gap, can be placed between Hall Sensor face & magnet.  They are a bit more expensive, but they may well be the solution, I need.  I'll order a few, & try it out.

Cheers Banjo

  

 

Edited March 11 by Banjo

[altezzaclub]

Sounds good!  They don't have to be 'in' the disc at all, but it would take a mill to make a hole so that they stuck out proud of the edge a mm or so.

[Banjo]

Once I get the magnets in the next few days, I can "statically" test them with the dual Haltech Hall Effect device; & find the largest air gap, that they will still trigger the Hall effect sensor at; reliably.

Then halve the gap, & I should have a very reliable system.  it took but about 10 minutes tonight, to put the dissy back on the 5K, & remove the COPs, & get the engine running; so I can dynamically test the trigger disk, & magnets, in isolation from them doing any controlling, or running the engine.

Cheers Banjo

 

[Banjo]

I haven't completed the mods to the camshaft sprocket cover as yet, but I have sited the aluminium disk, I purchased (6mm x 120mm), where it will be located; & it looks almost, as if it was designed for this application.

However, that's a few more precious hours, to finish that off, & then remove, the radiator, to get at the front of the "test engine", to remove & replace the camshaft sprocket cover, without removing the sump.  What I really need to do now, is test the concept, of a 200mm aluminium disk, with magnets facing out along the edge, rather than out the side.

So back to the A/C compressor bracket mounting points on the block, & a piece of bar, & it lines up  perfectly; as the centre of the crankshaft, is in line with the bottom edge of the block, which is approximately where the compressor bracket mounting holes are.  Ultimately, that Hall effect sensor, will be mounted on the cover pointing down to the edge of the disk, approximately 90 deg. from where it is in the picture below.

So before I fitted any magnets, to the "rim", of the aluminium disk; I want to ensure the disk was perfectly centred, & there was no run out.  The blank disks come as just that; cut with a laser, & with no centre hole.  No real issue finding the centre of the blank disc. Just 2 or 3 lines across the disk, towards the edge.  Measure the length of each, & find the mid point of each line. With a right angle set-square, draw a line at right angles , at the   mid-point.  These 2 or 3 lines should intersect at the centre point, of the circular disk. Then carefully drill at hole at the midpoint, & carefully enlarge, until you can get a reamer in there & gently remove only enough metal, until the crankshaft centre bolt, is a nice tightish fit, so there is no lateral movement in the plate, due to the hole being bigger, than the unthreaded section of the crankshaft pulley, retaining bolt.

I went through this exercise, & finished up, with a run-out of the edge of the aluminium disk, of less than 0.5mm.

I measured this run out, with a little metal "L" bracket, clamped so that you could turn the crankshaft, & measure the gap.

Normally, you would true the disk up in a lathe. However, I don't have a lathe, but the engine to which the disk is fitted, runs.  At idle; just hold a very fine file on the little shown silver bracket depicted; & because the aluminium is soft, & easy to work with; in just a few minutes, you have a perfectly concentric outer edge on the disk. 

It turns out the "diametric" round rare earth magnets, are made in limited sizes, & are very expensive; & I can't find the exact size I need, available in Australia.

So initially, I'm going to press small "rod" magnets into 36 holes drilled evenly around the edge of the disk.  The 200mm blank aluminium disk I purchased was not available in 10mm thickness; so I had to settle for an 6mm thick one. that should allow me, to drill & press in a 4mm dia. rare earth magnet.  I'll practice, of a piece of scrap 6mm thick aluminium, before I go drilling the disk, around the periferal edge.

Here is a pic, taken of the 200mm aluminium trigger disc, from the opposite side of the engine.  Now there is no water pump, & no water pump pulley, or fan blades, it certainly will "unclutter the front of the engine, directly behind the radiator. I've since found an a 200mm blank aluminium disc on Amazon, that is 8mm thick, so have ordered one; but it's coming from overseas, so will probably take a couple of weeks. 

So next post, I'll either be elated, that it is working, as intended; or back to the drawing board.  If it works, then the next job, will be building a Hall Sensor mount on the 120mm flat disk, on the camshaft sprocket cover, depicted in the first pic, in this post.

Cheers Banjo

 

 

Edited March 19 by Banjo

[Banjo]

Whilst I wait for my high strength rare earth magnets to arrive, in the next few days, & I now have a nice clean 200mm dia. aluminium disk, with a very true edge, where the magnets, will be inserted; so it's time to mark & drill the disk out, around the edge, to insert the magnets.

Now I could sit down with a protractor & fine black felt pen, & finish up with an accumulative error, as I worked around the 360 degree disk.

However, after searching the web, I found a site where you can draw a 360 degree disc, with markings; & then print out. It allows you to stipulate the diameter of the disc, & the size of the centre hole.

Quote

https://www.blocklayer.com/protractor-print

You can produce all sorts of customised things, from their base templates.

 

You can then save it as a pdf, & print it out, 1:1.  I then cut it out, & it fitted perfectly to the disc, & was easily centred, as the centre hole lined up perfectly. I then stuck it to the aluminium disk, with some thin double sided tape, & here is the result.

It is then a simple matter of working around the edge of the disk, & marking the edge with a fine black felt pen, so I can centre pop each point, so that accurate drilling can be carried out.

As my magnet trigger wheel, will have 36 magnets, it was really easy, as 360 degrees, is obviously equally divisible, by 36.

Next step will be to stand the disk up vertically, in the drill stand, so that the holes are at right angles, to the outside edge, & that the holes length heads towards the centre point of the disk.  That will result in the end of the magnet, being perfectly in parallel, with the face of the Hall Effect device.  I will start it off with a small "starter" hole, & then increase the holes' diameters, until there is an interference fit, so the magnets can be pressed into the disk.  I'll wait until the little N45 "rod" rare earth magnets arrive, so I can measure their diameter accurately, with my micrometer, to choose the final drill hole size, before insertion.

So far, so good !

Cheers Banjo

 

 

 

 

Edited March 19 by Banjo

[Banjo]

My special rare earth magnets should arrive today.  In the meantime, I've finished grinding down the outer face of the camshaft sprocket cover, & fitted the 120mm dia. aluminium disk, to provide a nice flat, firm, surface; to mount the Hall Effect sensor mounting bracket.

It worked out well.  Next process, will be to mount it to the front of the engine, then fit crankshaft pulley & trigger wheel, & design & build a little mount for the Hall Effect sensor.  

I've purchased a new crankshaft oil seal for the cover, & was pleased to find, they are still readily available.  It turns out, the front crankshaft oil seal, on the 5K engine, was used on a variety of Toyota smaller engines; hence they are still in good supply.  3K, 4K, 5K, 7K, 2R, 3R, 5R, 2T, 3T, 4TG & 12R  Toyota engines, all use this same seal.

I'll, not fit the seal, until the Hall Effect sensor bracket is designed, built, & fitted, as I'm sure the cover will be on & off numerous times, during that process.  I've permanently removed the four (4) sump connecting threaded studs at bottom of this cover, & replaced them with bolts; so that the aluminium cover can be removed & replaced without having to lower the sump each time.  It's a mod I've done to any K Series engine, I've worked on.

When finished, a few coats of a nice gloss enamel, will have it looking like the picture I discovered on the web, that started this little side project; & which I "coverted" so much  (greatly desired or envied); I simply built my own.  

Cheers Banjo

 

 

Edited March 21 by Banjo

[Banjo]

As well as bolting the aluminium disk to the "ground flat" front of the cover, I also glued it with Araldite, so there was no possiblity of any oil leaks.  This is how it turned out.

Next step, was to fit it all to an olde K series block, on an engine stand, in my garage; & see how the trigger wheel looked & physically sat.

Here is a closer view of the disk & Haltech Hall Effect sensor, mounted to a temporary bracket I made, to ensure the Hall Effect sensor face, lines up perfectly with the  centre of the outer edge of the 200mm aluminium disk.

It is also important, that the extended line of the Hall Effect sensor body length, passes through the center point of the disk, which it clearly does, in this case.

 

My previous experiments, were carried out with a 150mm dia. aluminium disk, but I chose a 200mm dia. disk this time; so that there is room to double the number of magnets to 72 off, (currently 36), so that greater resolution of engine RPM, & timing can be achieved, if required. The other consideration, is that depending on the sensitivity of the Hall Effect sensor, & the strength of the magnets, it may not be able to achieve a nice clearly defined "off" period, or gap, between pulses. Ideally, the mark/space, or on/off ratio of the on & off periods of time, should be about 50:50.  Only, whilst running it, & looking at the CRO (Cathode Ray Oscilloscope) waveform, will determine that. 

Ultimately, I will make the bracket, supporting the Hall Effect sensor, out of a block of aluminium, with a big hole through it for the sensor.  The least amount of steel close to the sensing face of the Hall Effect sensor, will reduce the possibility of magnetic field lines from the magnets, being deflected or attracted elsewhere.

So next step, is to fit it to the 5K engine, & do some serious testing.

Cheers Banjo

Edited March 25 by Banjo