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I am replacing my alternator backing plate and I discovered my fan hole is rounded.

It seems like this would only happen if the nut is loose but I had to use an impact wrench to get the nut off.

Other than torquing the nut to the proper value, is there anything else I can do to prevent this?

My welded and balanced fan came from Berg.  Is that still the best source?

1957 CMC (Speedster) in Ann Arbor, MI

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@Gordon Nichols, unfortunately, this is the best I can do for a photo. I recently replaced the cracked glass back on my phone and I must have touched the camera lens on the inside.

20220807_184439

@edsnova, I have been curious about Andrigs Fan and if I am going to install it this would be a good time.  But, reactions to it on thesamba have been mixed.  I am not sure it would really be a good move.

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  • 20220807_184439

I was talking to a bunch of the VW guys at Cars and Coffee and they said a lot of them run Andrig's fan and like it. Just for context, this is on Maui where it rarely gets up to 90F in mid-summer, so maybe not as challenging for engine temps.

I'm running a Berg's welded fan since I exploded the original unwelded fan. I like the idea of faster revs, but I'm not racing anybody and don't feel like taking it apart again. So, Andrig's is probably not for me.

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So, from what I'm reading, this was developed mainly for racer boys who were worried about fans flying apart at high rpm's, and it has the added advantage (for racer boys) of being lower mass and thus spinning up faster and it also cools well at those high speeds.

But most of us have the opposite concern - good cooling at lower speeds, especially sitting in traffic at idle. Any reports on how this fan does there?

My car is most likely to run warm on a hot day after the engine has been run hard and we're now slogging through urban traffic on those last few miles towards home. Usually, the engine will actually drop in temperature climbing a long, steep hill if I downshift and get the revs up. My stock fan (with welded vanes) has run with no issues for about 40K miles.

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Last edited by Sacto Mitch

I installed Andrig's fan this last winter.  I had his first iteration and the fan housing cracked under pressure of the nut.  He sent his new design for free.  It seems to be working fine.   It is so much lighter than the stock and feels like nothing compared to a welded fan.  It provides cooling at least as good as the stock and maybe slightly better.  I think its a great product and pretty cheap.

@Stan Galat, I am close to convincing myself to do it.  There is another member of this group, who shall remain nameless, who I believe has already purchased one of these fans.  I sent him a PM yesterday but he hasn't responded.

I now think the fan hole became rounded when my engine was a 1776.  Then, after the engine became a 2110, the super tight nut kept the fan from rotating on the shaft.  I bought a nice electric impact wrench to get the nut off. It might be one of those nice but rarely used tools.

The first thing I plan to do is slot the holes in the alternator stand close to the shroud and replace the studs on the other side with bolts.  Then, if Andrig's fan doesn't work out I can swap it without pulling the engine and shroud.

@Sacto Mitch posted:

But most of us have the opposite concern - good cooling at lower speeds, especially sitting in traffic at idle. Any reports on how this fan does there?

My car is most likely to run warm on a hot day after the engine has been run hard and we're now slogging through urban traffic on those last few miles towards home.

This confuses me a bit, and I'm not being snarky or sarcastic - but do you not have a remote cooler with a fan? I don't think you've got a CHT gauge, so when you talk about "running warm", I think you mean oil, correct?

I understand the situation (brisk run, then sitting in hot traffic), but I don't think any crank-spun fan is going to cool anything that is already hot down just spinning at idle. I've got a T4 oil cooler on the stand, but I've always just thought of it as a supplement to the remote cooler, which was doing the heavy-lifting for bringing down the oil temperature. Everybody's got a different take on ACVW T1 cooling, but I'm in the camp that the Sainted German Engineers didn't ever anticipate a 150 hp T1.

I think of the shroud and fan as a head cooling setup with a cute little oil cooler as a secondary oil cooler. I think of the remote cooler as the primary oil cooler.

If you're oil is running hot sitting in stop-and-go traffic, that seems to me to indicate that the remote oil cooler setup is inadequate.

Thoughts?

The first thing I plan to do is slot the holes in the alternator stand close to the shroud and replace the studs on the other side with bolts.  Then, if Andrig's fan doesn't work out I can swap it without pulling the engine and shroud.

I always pull the studs and just put bolts in on all 4. If I'm having machine work done on the case, I have them put time-certs in, but for the rare times you're going to install and remove it - I think just threading into the magnesium or aluminum is fine.

Please report back to us your findings/thoughts. This is something I've been considering for a while.

Last edited by Stan Galat

Wolfgang........Years ago, before VW offered alternators,  I gutted a generator housing and stripped the armature down to just the center shaft,  welded mounting brackets to the generator housing to accept a small Motorola alternator. found a double sheve pulley to fit the generator shaft.  (two belts)  Voila !  I had a VW with an alternator !  It worked fine for about two years and then came apart.  On disassembly,  I found that the long 9/16" shaft inside the generator was destroyed due to radial flexing as it turned. It wasn't worth making a new/bigger shaft because VW had now came out with an alternator.

Bruce

VW made millions of engines with the squirrel gage fans, just replaced it with a stock new OEM German fan or a quality welded and balanced fan.

Maybe I'm just crusty this morning (and I really don't want to come across as such) but...

  1. The fact that VW made millions of something doesn't mean it's adequate for a high-performance application. The fan is spinning significantly faster than the crank (about 1.8: 1), and VW never anticipated their fans spinning over 10,000 RPM - but it will be if you rev to 5600 RPM or higher.
  2. I'm not trying to be pedantic, but as far as I know - there are no "new OEM German fans" left, and probably haven't been for 30 years. There are old OEM German fans, and new aftermarket Asian fans, and maybe even some NOS Brazilian or Mexican OEM fans, but no new German OEM fans, unless I'm badly mistaken. What's available is not likely to be as good as what VW used on their millions of (low-revving) T1 German engines.
  3. IMHO, a welded/balanced fan is the bare minimum if you plan to spin the motor past 5000 RPM, but I've seen quite a few EMPI "welded/balanced" fans with 1/4" of runout. All "welded/balanced" fans are not equal, they're not a commodity. I'd definitely get one from Pat if I were shopping.
  4. I've ripped the centers out of two different fans - the wheels are heavy, and act like a big-'ol flywheel, impeding acceleration. It's a thing.

I think Adrig's fan is really intriguing.

The idea that the German cooling system cannot be improved upon is deeply ingrained in the psyche (maybe even the DNA at this point) of the VW hi-po hobby, but I just don't get it. Everybody agrees that very nearly every other aspect of the engine can be improved upon - what makes the cooling system sacrosanct?

Last edited by Stan Galat

The first thing I plan to do is slot the holes in the alternator stand close to the shroud and replace the studs on the other side with bolts.  Then, if Andrig's fan doesn't work out I can swap it without pulling the engine and shroud.

I tried this a few years ago and it has been helpful when changing alternators. All bolts might be better since you're less likely to damage the gasket sliding the alternator stand around. I like @Stan Galat's point about adding time-certs if the opportunity presents itself.

On the topic of oil coolers, I don't see a good reason for keeping one inside the shroud. It just contributes to the heat load and temps inside the engine compartment. I got a 36hp shroud, blocked off the internal cooler and put in a thermostatically controled external cooler with a fan in the wheel well.

@Stan Galat posted:


The idea that the German cooling system cannot be improved upon is deeply ingrained in the psyche (maybe even the DNA at this point) of the VW hi-po hobby, but I just don't get it. Everybody agrees that very nearly every other aspect of the engine can be improved upon - what makes the cooling system sacrosanct?

This is so true with the VW crowd and even the modern day car crowd as well. I'm on at least one other forum related to Porsches, specifically my 718 that will arriving later this year. Every time someone mentions they've made some modification to the motor, exhaust, or suspension inevitably someone says, "The engineers that designed XXXXXXXX know far better about what they're doing than some other aftermarket company blah blah blah.

I simply can't agree with such a statement. Maybe if you're building a car that costs $2 million bucks and only making a very limited number of them like a Bugatti Chiron or something. But all mass producing car companies, hence all automotive engineers, make what is good for the masses and what will appeal to hundreds of thousands or maybe millions of people. The first consideration is usually based on cost first then performance. Not everyone wants their car to be lower than the stock ride height you see on whichever current car you're looking at. Not everyone wants the mundane boring exhaust system that comes standard. And it is those people who disagree and they lower the car using aftermarket parts designed with performance in mind then cost. They put in better performing exhaust systems and they put in higher performance engine bits. Because if you're replacing it you probably don't care what it costs but you do care about how it performs.

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@Stan Galat posted:
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...I think of the shroud and fan as a head cooling setup with a cute little oil cooler as a secondary oil cooler. I think of the remote cooler as the primary oil cooler.

If you're oil is running hot sitting in stop-and-go traffic, that seems to me to indicate that the remote oil cooler setup is inadequate.

Thoughts?



Stan, my cooling system is master of its domain. I don't have any overheating issues. When I say 'running warm', I mean a little towards the high side of its usual range (the oil temp needle drifts a little north of its usual, centered place on the gauge).

I've got a stock cooler in the doghouse besides a Setrab in the wheel well. I control the oil cooler fan manually. I did this initially just for simplicity (one less thing to fail), but I've found it gives me a little better info about what stresses the engine as I drive. I can also know for certain if the fan is working or not. With a thermostatic switch you never know for sure if the fan is coming on when it should, if the switch has failed, if the fan has failed, or if one of them is working intermittently. (I'm not overthinking this, am I?)

The normal drill is to drive until the needle approaches half and then I switch the fan on. Some days, I never need the fan. In warmer weather, I just leave the fan on once it's on. On some days, it's just cool enough that I'll have to switch the fan off after it's been on a while.

What I do notice, with the fan on or off, is that climbing a long hill in a lower gear, with the revs at, say, 4000, the oil temp does noticeably drop. So, the engine fan may be cooling mainly the heads, but that in turn is cooling the oil, too. Or, maybe the cute little cooler in the shroud is doing some real work as well. At any rate, with a thermostatically controlled fan, I would just assume that that had kicked on while climbing the hill. This is another small example of how watching the gauge and switching the fan manually gives you a little more info about what's going on.

And besides, I just like playing with toggle switches.

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Last edited by Sacto Mitch
@Gotno356 posted:

Mike,

did you see any difference in oil temp after that mod? Up or down?

Tom.

I ran with both an internal cooler and an external cooler/oil thermostat/thermostat controlled fan for a year before switching to using only the external cooling system. No oil temperature differences were detected.

The external oil thermostat recirculates the oil back to the engine if the oil temp is less than 180F. The fan is set to turn on when oil in the cooler is above 180F. This helps to bring the engine temp up to running temp when doing a cold start.

On the topic of oil coolers, I don't see a good reason for keeping one inside the shroud. It just contributes to the heat load and temps inside the engine compartment. I got a 36hp shroud, blocked off the internal cooler and put in a thermostatically controled external cooler with a fan in the wheel well.

I'm absolutely tracking with you on this.

Over on TheSamba, they have a bi-yearly love-in for the stock cooling apparatus, and there's always some highly respected guy from North Saskatoon or Outer Elbonia or North Pole, AK who pipes up with a "I've got a 2.7L 12:1 engine and I run a stock T1 shroud and doghouse cooler and never had any issues".

He doesn't drive further than to the DQ for a $56.98 Blizzard or at all "when it's really hot out", and he's got no oil temperature gauge - but he just knows that the Sainted German Engineers had it all figured out. Nobody dares cross him, because he knew enough to build his 2.7L 12:1 T1, and nobody else did, so it passes from the experience of one guy in a cold climate and into the cannon of VW folklore and common-knowledge gospel.

Also, Gene Berg loved them on his 7:1 compression specials. Full stop. That alone is enough to end any argument.

The stock cooling system cannot be improved upon, or so goes the story. The Sainted German Engineers toiled for decades on this before God Almighty opened the heavens and descended down to Wolfsburg to hand them the knowledge directly. It was written on a little scroll and they ate it - it tasted like honey in their mouths but was bitter in their throats.

It's therefore as good as any air-cooled setup has ever or will ever be, whether the engine in question is a 1200 cc Typ 122 or a Pauter 3L. Heaven protect you from the Keepers of the Flame if you have the audacity to run a 911-style setup: the tar-and-feather treatment is is too mild for such heresy - apostates and witches must be burned at the stake, their bones scattered in the dung-heap.

I've run DTMs for years on strokers. They're cheesy bits of fiberglass for sure, but they seem to work really well. I put T4 coolers in them because that's what they're set up for - but the stand cooler seems like a real nothingburger to me. It really makes me wonder what an aftermarket (Scat or EMPI, I don't think there's a bit of difference) wide-fan, 36 hp "doghouse" shroud without the doghouse or attendant cooler would do.

I always thought this would make a neat science project for somebody, and now Michael has done it.

To continue the riff:

I really like the T1, and by that I mean that I REALLY like it. But, I've been on record many times as saying that the oiling system seems as if it was designed on a fine Friday afternoon in October, somewhere around 4:45, with the windows open in the office. The bier tent was already set up, the tubas were tuning up down in the square, and Oktoberfest was about to fire up. They could hear the giggles of the frauleins who were already tapping the kegs. The boss had told the team they needed to be done by 5:00. They finished by 5:00.

Either that, or they meant it as a joke, but either way - it seems less "ingenious" than "convoluted" to control temperature with viscosity among other things. Because one bypass spring was too bizarre for the ignoramuses who WEREN'T Sainted German Engineers to adequately appreciate, they added a second later on. Doubling down on bad decisions is what makes Germans German.

I'm just a high-school graduate from Nowhere, USA who always thought it seemed like it might be a better idea to cool the heads with air from the fan and the oil with (I don't know, and call me crazy) a dedicated OIL COOLER.

Jump back- an oil cooler just for oil? Separate from the head cooling? Why would anybody want that?

Those klever krauts couldn't do that though, it might have added $4 to the cost of the car, and Der Feurer might send them to the eastern front - so they piggybacked the cooling fan on the generator/alternator, and the oil cooling on the head cooling setup and saved the $4. For this they received the Iron Cross and all the cyanide they could eat down in the bunker with old AH.

I can almost hear them now, their voices echoing down through the decades. "Be glad we added an oil cooler at all! It was Friday in October. We blocked off the air to number 3, but whatcha-gonna-do?"

I'm sure it must have been just like that.

Last edited by Stan Galat

@Michael Pickett, I always want a bier.

When I was first specing out my Speedster I was completely ignorant about VW engine concerns, having cut my teeth on MGs.  One of the first tips was to spec an oil cooler, and I did so without question because I didn't realize that the Sainted German Engineers knew better.  Somehow it never caused me to run too cool.  Whew!  Dodged a bullet there I guess.

@barncobob posted:

16:1....thats is past diesel compressions which are high

Static compression means nothing. It's dynamic compression that matters.

16:1 static with huge ports, huge carbs and intake, huge cam, and huge exhaust will be much lower in dynamic compression. Pat is building a drag motor that probably doesn't have ANY cooling system at all.

I was told my 10.2:1 engine would melt on the street. It hasn't(dynamic compression is in the desired range of 8 to 8.5:1).

I am running a 911 shroud. I was told that doesn't work either.

I only have a thermostatically-controlled plate cooler, none in the shroud. They said that's the way to kill the engine too.

I was also told it would NEVER cool evenly. I added a slightly modified Porsche 911SC vane on the back of the alternator. I monitored all 4 cylinder head temps for a while. The cylinders stay within 20 degrees of each other. Good enough.

It used to overheat when idling or moving very slow in HOT weather. I added sled tins to keep the spent air from recirculating into the fan intake. It worked, and dropped head temps ten degrees across the entire temp range.

I have an Autocraft dry sump and a bit over 6-7 quarts in the system. Engine is full flowed, the bypass valve is on the oil filter flange(JayCee) and goes back to the oil tank. There is a custom-made(Autocraft) oil pickup that bolts to the VW sump with AN10 line directly to the oil pump scavenge stage(52mm gears). The pressure side is 26mm.

There isn't a single thing "stock" about my air or oil cooling system. Exactly zero engineers of any nationality were consulted.

When I remove the valve covers there is not a single drop of oil in there. The scavenge pump actually draws a vacuum on the case. This is good for ring sealing and minimizing blow-by.

None of this is "designed" but it works. And it works well indeed. It was not cheap, but it was less than a set of Nickies cylinders, that's for sure.

@Sacto Mitch posted:

.

So, from what I'm reading, this was developed mainly for racer boys who were worried about fans flying apart at high rpm's, and it has the added advantage (for racer boys) of being lower mass and thus spinning up faster and it also cools well at those high speeds.

But most of us have the opposite concern - good cooling at lower speeds, especially sitting in traffic at idle. Any reports on how this fan does there?

My car is most likely to run warm on a hot day after the engine has been run hard and we're now slogging through urban traffic on those last few miles towards home. Usually, the engine will actually drop in temperature climbing a long, steep hill if I downshift and get the revs up. My stock fan (with welded vanes) has run with no issues for about 40K miles.

.

I think that's most of the idea. And from the Samba thread (for what that's worth), it seems at least one Bus guy got worse results with the Andrig fan than with a stock setup.

Based on my scant experience, fortified with the engineering expertise imparted by a BA degree in journalism, I've developed a theory: I think the Andrig fan is probably very good or even excellent for applications in which the air pressure in the engine bay is generally positive, and is probably less good for situations of low or negative air pressure.

The stock hamster wheel fan seems really good at creating a vacuum into the fan shroud, even at idle. We all know this from experience with shop rags or cigarette packs or (as in my case) the loose spare tire hold down strap with its brass buckle. A stock VW fan will suck any and all of those things into its vortex on startup. Will an Andrig fan?

My guess is yes. But slightly less aggressively.

BUT!

At 4500 RPM or higher, in a situation wherein the vehicle is pumping air into the engine bay already, Andrig might work better than stock, which reportedly causes belt slippage and air stall at high RPM. That could explain why FJ Camper got good results on his racing Ghia.

All of which is fodder for someone—or several someones—with a good CHT setup.

Last edited by edsnova
@Stan Galat posted:


The stock cooling system cannot be improved upon, or so goes the story. The Sainted German Engineers toiled for decades on this before God Almighty opened the heavens and descended down to Wolfsburg to hand them the knowledge directly. It was written on a little scroll and they ate it - it tasted like honey in their mouths but was bitter in their throats.



What you've identified is our human love of nostalgia, our tendency for reverence of the old things, and our penchant for ascribing special skills to particular races. Nostalgia can be a lovely thing when applied to families and art and music, but it really has no place in engineering, and the rest of it is pure hokum.  These things applied to T 1 cooling systems is not only laughable but it ignores something that transcends all production engineering, German or otherwise. Production engineering is mainly a process of compromises. Nothing is optimized for function alone.

"Claus, we would really like to thread the generator stand and use bolts so we could service the fan without removing the engine!"

"Nein, Rudolph, that would add extra manufacturing steps and the bolts are more expensive than the studs.  We would never make our schedule or cost targets."

"Well, then can we at least weld the fan to reduce the potential need for service?"

"Ach, NEIN! Rudolph, stop thinking about getting it 100% right. 80% is good enough, people will accept it, and it's all we can afford!"

And there you have it. An aftermarket company can direct all of its resources at one thing because the deeply disturbed (that's us) will pay more to get that one thing right. They also have more advanced manufacturing processes and materials available to them than the sainted German engineers did.

I'm non-plussed at how a Samba poster can wax poetic about how much better the heads can be made to flow while insisting in the same breath that the cooling air and oil flow was maximized in the 1930's. That's why I avoid the Samba because those threads remind me of the Amish and the Mennonites and the Hassidim.  It is more about what one reveres and where one draws a line in the technological sand than it is about engineering. Religiously held views, coupled with revered inanimate objects, combined with anonymous commenting rarely goes anywhere good or useful.  The signal to noise ratio is more than I can tolerate and I no longer find it amusing. (And the Subaru sites are no better)

Last edited by JMM (Michael)

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