OEM radiator?

[Helirich]

I've read that the OEM radiators are not good quality. The problem is the plastic end caps. I've had no problems with my cooling system, but it sounds like a problem I don't want. I just went down to measure the fans and noticed the ends on my radiator are made of metal. (Not plastic) Does that mean the PO allready changed it out? (I hope) Were any stock radiators all metal? If some stock radiators were metal, are they still bad for some reason?

That would be great news, but the fan motors definitely look to be old. They are very long. The shroud looks to be in good condition. I was going to replace the whole works, but if you guys confirm I have a good rad, all the better.

As best as I could measure, the fans were 10" across. Can someone confirm this? (It's kind of hard to measure) I really want to go to brushless fans.

[Helirich]

I thought I would copy and paste this from another site. I know the guy that wrote this and he knows his stuff. It's a long read, but worth it.

Compiling all the cooling tech into one thread. Not limited to just fans.

Brushless:
Brushless fans are taking over the OEM and aftermarket and they are starting to show up on the newer ULTRA4 builds. The most common right now is the brushless Spal fans and they are easy to tell from the motor design. The ones shown below are the GEN 2 motors. The older Gen 1 motors and controllers are discontinued as they have a different electrical signal system and do not interchange with GEN 2. The motors also look different.
The brushless fans also have all the new tech in the shroud and blade design compared to the older brushed versions. Some of them might look backwards as they are going towards a recessed/flush drop in shroud/fan style versus the traditional surface mount that sits up high. The deeper shroud design allows better air flow through the core. The deeper blade designs are also because they are more powerful and pull more pressure and it also makes them a quieter as the rpms are lower so the frequency is lower and less annoying.
The brushless fans are always connected to power and a third and fourth signal wire is used to turn the fans on. No external relays or controllers, everything is inside the motor. The signal can can be a constant on full rpm or a PWM signal to variable the rpm. The Spal temp sensor is a smart sensor that outputs a PWM signal with a percentage based on the predetermined temp range by the part number. If you dont use a sensor, one signal wire is grounded (-) and one is powered (+) and it doesn't need anything else to run.
When the fans start up they wiggle to find home and then slowly ramp up to the signaled speed. If you physically block the fan blade the controller will fault out and reset and try to power up again until the obstruction is removed. The fan also has overload protection and overheat protection. For instance mud or water, stick, or a bent shroud dragging on the blade. It can derate its power output to stay cool if things get too hot but at those temps your engine should be on fire. The sensor has a ramp so it starts out low say 25% and ramps up if the sensor temps are not dropping, so it only uses what power it needs to cool. One sensor can power multiple fans so they can all power up together and not have to stagger start them or have one pull air through the shroud if the other one is off.
Lastly is the run life of 30,000 hours at which 95% will keep going and 5% might fail. The brushless motors dont have brushes to wear out and are more efficient so they will outlast most any other moving part on a buggy. The other big part to life is that they are IP68 and IP6K9K so they keep water and dust out of the motor and controller.

Noise:
Noise pertains to both brushed and brushless. The small diameter thin blade designs are the worse for noise as they need to turn faster to make the same airflow as the deep curve blades, so their frequency goes up.

Blade and Guard Design:
This pertains to both brushed and brushless. Thin blades can not pull the same CFM with high restriction radiator cores. Free air yes, but load them up and they can not move the air like a thick blade. The thin blade guard designs don't handle the bottoming out and G force as well as the heavier built thick blade shrouds which have more support. That is why you will see CBR and others build metal support straps for the thin fans. The new brushless housings are taking the share of the R&D so the strength and blade design are on a whole nother level.
One of Spals first brushless fans was based off of a brushed housing and blade design that had a brushless motor droped in. The setup as good as it was was not optimized and ranged between 24-33 % efficiency. When the same 300W brushless motor is dropped into an optimized blade and housing the efficiency raises to 32-40%. The performance under higher pressures also jumped. At 180Pa the old fan put out 1000CFM while the optimized blade put out 1357CFM.

Temp Sensor Location:
My understanding from talking with Spal is to put the sensor on the hot side loop which includes the driver front of head or passenger rear of head or water pump outlet or on the radiator before it does any cooling so you have a faster reacting system and so the reading temps are in a closer range. The factory ECM triggers the fans based off of what the heads read. I have the factory ECM sensor in the front driver head, Autometer sensor in the passenger rear head, and thinking of putting the Spal sensor in the hot 5/8 outlet heater port that is currently blocked. FYI, the 3/4" heater port is the low pressure side return which is connected to the surge tank.

[Bitsyncmaster]

This all may be good for a race car but with AC the fans need to be moving as much air as possible. I do like the idea of ramped up start current but that is only nice if your fans are switching on and off a lot.

An OEM fan blade is 10.7935" in diameter.

[steve]

This all may be good for a race car but with AC the fans need to be moving as much air as possible. I do like the idea of ramped up start current but that is only nice if your fans are switching on and off a lot.

Absolute Radiator Store may have what you want.

[David T]

All Deloreans came with plastic tanks, no exceptions unless you are talking about prototypes. Nothing wrong with the plastic tanks except they got old. If you already have a tank with metal tanks, the radiator was replaced at some point in the past. That said, you might want to replace the fans. Depending on where you get the fans, you might have to remove or modify the shroud. The other common failure point is the header tank. The OE plastic one bursts. Replace with a metal tank unless it has also already been replaced. Next is the hoses. If they are old or hard they should ALL be replaced. That includes the ones under the intake manifold.

[Ron]

An OEM fan blade is 10.7935" in diameter.:)

[Helirich]

This all may be good for a race car but with AC the fans need to be moving as much air as possible. I do like the idea of ramped up start current but that is only nice if your fans are switching on and off a lot.

An OEM fan blade is 10.7935" in diameter.

I guess I'll be making my own shroud.

On the brushless motors, why the reference to a race car? These are on stock cars. (Will be on all cars eventually) The brushless move more air than the older fans for the same or less power. What is it that you don't like?

[Bitsyncmaster]

I guess I'll be making my own shroud.

On the brushless motors, why the reference to a race car? These are on stock cars. (Will be on all cars eventually) The brushless move more air than the older fans for the same or less power. What is it that you don't like?

I like the idea of less power but have not seen any data to prove that. Race cars don't use AC, or do they?

[Helirich]

I like the idea of less power but have not seen any data to prove that. Race cars don't use AC, or do they?

I would suppose that depends on the kind of racing and seriousness of the driver. Lol. But a race car would definitely want the most proformance for the weight and amp draw.

So I just goggled it and I could only find references to cordless drills. They claim 25% increase in power and the life is only limited to bearing life. They also claim no sparks to ignite anything. This site was not selling anything.

[Bitsyncmaster]

I would suppose that depends on the kind of racing and seriousness of the driver. Lol. But a race car would definitely want the most proformance for the weight and amp draw.

So I just goggled it and I could only find references to cordless drills. They claim 25% increase in power and the life is only limited to bearing life. They also claim no sparks to ignite anything. This site was not selling anything.

Find a spec sheet showing less power for equal air flow and I will order one just to test it. You know I love to reduce current consumption and I have a hot wire anemometer.
.

[Helirich]

Find a spec sheet showing less power for equal air flow and I will order one just to test it. You know I love to reduce current consumption and I have a hot wire anemometer.
.

I'm leaving for Delaware tomorrow. I'll be gone at least a week. If I order one and have it sent to you, you could do all the testing you want and send it on to me. Is that a fair deal?

[Bitsyncmaster]

I'm leaving for Delaware tomorrow. I'll be gone at least a week. If I order one and have it sent to you, you could do all the testing you want and send it on to me. Is that a fair deal?

That would be great. By the way, I had a customer insist on keeping OEM fans which were drawing 15 amps each when he was at my house. But that would trigger my overheat warning on my fan fail. He finally swapped to a vendors lower power fans and said his engine temps still stay in the green. He lives in Florida now also. So I don't think you need higher volume flow fans for the DeLorean.

[Helirich]

That would be great. By the way, I had a customer insist on keeping OEM fans which were drawing 15 amps each when he was at my house. But that would trigger my overheat warning on my fan fail. He finally swapped to a vendors lower power fans and said his engine temps still stay in the green. He lives in Florida now also. So I don't think you need higher volume flow fans for the DeLorean.

I agree mine are working. I just drove today in very hot conditions and it stayed at the 160 line.

I will send you a PM about the fan.

[MrChocky]

That would be great. By the way, I had a customer insist on keeping OEM fans which were drawing 15 amps each when he was at my house. But that would trigger my overheat warning on my fan fail. He finally swapped to a vendors lower power fans and said his engine temps still stay in the green. He lives in Florida now also. So I don't think you need higher volume flow fans for the DeLorean.

There are people who swear up and down that the OEM fans have better airflow. That seems dubious to me, but so be it.

[FABombjoy]

There are people who swear up and down that the OEM fans have better airflow. That seems dubious to me, but so be it.
Direct comparisons seem to be confounded by a combo of "lack of original part numbers", reliance on manufacturers specs, and anecdote.

For example: OEM -vs- Supplier1 -vs- Supplier2
Rather than: OEM -vs- Spal 30100364 -vs- Derale 16920

Then you add in owner's anecdotal tests w/out any standardization - OEM shroud / metal shroud / no shroud, aluminum or brass radiators, etc - and it's impossible to draw conclusions without a lot of anecdote.

Dave did some great genuine research & measurements here:
http://dmctalk.org/showthread.php?4932-Radiator-Fan-Test-Data
The data suggests OEM fans flow more but at quite a current cost

[Bitsyncmaster]

Direct comparisons seem to be confounded by a combo of "lack of original part numbers", reliance on manufacturers specs, and anecdote.

For example: OEM -vs- Supplier1 -vs- Supplier2
Rather than: OEM -vs- Spal 30100364 -vs- Derale 16920

Then you add in owner's anecdotal tests w/out any standardization - OEM shroud / metal shroud / no shroud, aluminum or brass radiators, etc - and it's impossible to draw conclusions without a lot of anecdote.

Dave did some great genuine research & measurements here:
http://dmctalk.org/showthread.php?4932-Radiator-Fan-Test-Data
The data suggests OEM fans flow more but at quite a current cost

I still have a set of OEM fans mounted on an OEM radiator and OEM fan shroud. I will use those to compare when I start testing that new brushless fan. I wish I had a junked AC condenser on my test set up.

[Helirich]

Direct comparisons seem to be confounded by a combo of "lack of original part numbers", reliance on manufacturers specs, and anecdote.

For example: OEM -vs- Supplier1 -vs- Supplier2
Rather than: OEM -vs- Spal 30100364 -vs- Derale 16920

Then you add in owner's anecdotal tests w/out any standardization - OEM shroud / metal shroud / no shroud, aluminum or brass radiators, etc - and it's impossible to draw conclusions without a lot of anecdote.

Dave did some great genuine research & measurements here:
http://dmctalk.org/showthread.php?4932-Radiator-Fan-Test-Data
The data suggests OEM fans flow more but at quite a current cost

On a helicopter cooling fan my company was working on many years ago, it had a stainless fan that was just cut out with a waterjet and twisted blades. We hired a fan expert and he made two suggestions. The first was to add a curve to the lip of the shroud. That didn't seem to make much differnce and it wasn't worth the production costs. But he also recommended the fan blades be "cupped". That made a world of differnce. That was on a pusher configuration. He told us that a fan like ours is good for velocity, but no good for pressure. (We needed pressure) The cupped blades helped a lot, but were not ideal. Robinson helicopters use a squirrel cage fan which he said was much better for the application. (To hard to design into our aircraft)

While our fan is not good for pressure, it should be fine in a puller configuration. The OEM fan shroud looks good to me. It would be nice if I could incorporate the brushless fan into it, but I doubt I can. I am pretty good with sheet metal, so I think I can come up with something.

[MrChocky]

Direct comparisons seem to be confounded by a combo of "lack of original part numbers", reliance on manufacturers specs, and anecdote.

For example: OEM -vs- Supplier1 -vs- Supplier2
Rather than: OEM -vs- Spal 30100364 -vs- Derale 16920

Then you add in owner's anecdotal tests w/out any standardization - OEM shroud / metal shroud / no shroud, aluminum or brass radiators, etc - and it's impossible to draw conclusions without a lot of anecdote.

Dave did some great genuine research & measurements here:
http://dmctalk.org/showthread.php?4932-Radiator-Fan-Test-Data
The data suggests OEM fans flow more but at quite a current cost

Well, yes, Exactly. For now, both my cars have original (or apparently so) fans, and until there's a compelling reason otherwise, or I somehow run out of
other things to fix, they'll stay like that. Certainly the cooling in my driver seems to work extremely well; only twice has the needle threatened the first
mark on the gauge. I'm less convinced that things are OK in the project, but won't know for a while.

[Timeless]

That would be great. By the way, I had a customer insist on keeping OEM fans which were drawing 15 amps each when he was at my house. But that would trigger my overheat warning on my fan fail. He finally swapped to a vendors lower power fans and said his engine temps still stay in the green. He lives in Florida now also. So I don't think you need higher volume flow fans for the DeLorean.
I'm in South Florida and recently installed a new DMCH radiator and DPI fans. Engine temps stay cool so far and I'm sure it will do well even during our hot/humid summers.

[David T]

If you are moving over around 30 MPH you don't even need the fans to provide enough cooling if the cooing system is in "good knick".

[Helirich]

I'm in South Florida and recently installed a new DMCH radiator and DPI fans. Engine temps stay cool so far and I'm sure it will do well even during our hot/humid summers.

Bitsyncmaster finished all his testing for me in another thread, but the results were the DPI fans were the best. I installed them on my stock radiator long ago. They have allready been through last summer. You won?t have a problem.

[Timeless]

Bitsyncmaster finished all his testing for me in another thread, but the results were the DPI fans were the best. I installed them on my stock radiator long ago. They have allready been through last summer. You won?t have a problem.
This is good news - thanks.

[82DMC12]

Bitsyncmaster finished all his testing for me in another thread, but the results were the DPI fans were the best. I installed them on my stock radiator long ago. They have allready been through last summer. You won?t have a problem.


Which thread is that? I haven't seen it. Thanks

[Bitsyncmaster]

Which thread is that? I haven't seen it. Thanks

I think this is the one. But I've done lots of other fan test threads.

https://dmctalk.org/showthread.php?18989-SPAL-brushless-fan