Big Blue's Transformation

[Gary Lewis]

BE is plenty granular enough for that. Below is the table for that, with my #'s on the left and Bill's on the right. And while it says it is an "air adder" I think it is actually RPM adder. So I need to make my 220F entry something like 150 to rev it up some, but not so much that it would be a huge surprise to the driver.

Also, there is the ability to raise the idle when the A/C comes on, or even kill the A/C when the ECT hits a certain temp - but in that case the ECU has to be controlling the A/C clutch, and in my case it is just monitoring it.

Actually, setting 220F to 150 won't work as then the adder would never reach 0 since the ECU interpolates between the values. So the desired RPM would never reach my target of 648.

As I think about it, my table was developed before I realized that the ECU wasn't controlling the idle RPM. And I was trying to add enough RPM to have it come down slowly. But now that the ECU is controlling the RPM that approach isn't needed.

I think I'll adopt Bill's #'s where it goes to 0 at 160F and starts back up at 214F.

[85lebaront2]

BE is plenty granular enough for that. Below is the table for that, with my #'s on the left and Bill's on the right. And while it says it is an "air adder" I think it is actually RPM adder. So I need to make my 220F entry something like 150 to rev it up some, but not so much that it would be a huge surprise to the driver.

Also, there is the ability to raise the idle when the A/C comes on, or even kill the A/C when the ECT hits a certain temp - but in that case the ECU has to be controlling the A/C clutch, and in my case it is just monitoring it.

Same on Darth, the ACCS (Air Conditioner Clutch Switch) has an input to the ECU to tell it to raise the rpm for the compressor load. It may do just that, add enough air to compensate.

GM and Chrysler actually have the ECU control the AC compressor relay. On both it keeps the compressor off on start until the idle settles a bit, just a few seconds. I know on the Chrysler systems it will kill the compressor at WOT, but all I have really delved into are the 4 cyl turbocharged engines.

[Gary Lewis]

Actually, setting 220F to 150 won't work as then the adder would never reach 0 since the ECU interpolates between the values. So the desired RPM would never reach my target of 648.

As I think about it, my table was developed before I realized that the ECU wasn't controlling the idle RPM. And I was trying to add enough RPM to have it come down slowly. But now that the ECU is controlling the RPM that approach isn't needed.

I think I'll adopt Bill's #'s where it goes to 0 at 160F and starts back up at 214F.

Ok, here's my next table and the rationale therefore. However, remember that these are adders to the base idle RPM of 648.

• Extremes: You have to have the two extremes of -256 and 254F. And since my stock tune had them both at 304 I left them there.

• 0F: I wanted the RPM with the ECT at zero to be around 800, and I found that making the adder at 86F to be 120 then at zero the adder would be 166 which makes the RPM @ 0 = 814. Close enough.

• 0 Adder: Both Bill's and my original tune took the adder to zero at 160F, but I wanted it to go a bit slower so set it to 17F0F.

• Ramp Up: I don't want the additional RPM at high temps to come in suddenly, so started at 210 instead of 220 and ramped in pretty much a straight line. But this may not be enough?

Thoughts?

[Gary Lewis]

Ok, here's my next table and the rationale therefore. However, remember that these are adders to the base idle RPM of 648.

• Extremes: You have to have the two extremes of -256 and 254F. And since my stock tune had them both at 304 I left them there.

• 0F: I wanted the RPM with the ECT at zero to be around 800, and I found that making the adder at 86F to be 120 then at zero the adder would be 166 which makes the RPM @ 0 = 814. Close enough.

• 0 Adder: Both Bill's and my original tune took the adder to zero at 160F, but I wanted it to go a bit slower so set it to 17F0F.

• Ramp Up: I don't want the additional RPM at high temps to come in suddenly, so started at 210 instead of 220 and ramped in pretty much a straight line. But this may not be enough?

Thoughts?

Apparently y'all fully agreed with my rationale, which is good because it appears to work.

Today I wrote that tune into the ECU and, sure enough, had to pull Fuse 10 to make the ECU forget something. (I made the keep-alive fuse #10 instead of #9, Bill.) But after doing that it started up nicely, although it was again quite lean since the computer had forgotten what it had learned.

To test that tune I warmed the engine up and then started data logging. The graph below starts with the ECT @ 196F, the A/C on Max, and the ambient temp at 94F. The vertical white line is at the point where the ECT was 209.488 and the desired RPM was 640. But at the very next data point the desired RPM had gone to 656 and the ECT started climbing, as did the desired RPM.

Ultimately the ECT stopped climbing at 225F and the desired RPM was wavering from 784 to 816. At that point I moved the truck to cool the engine down, which you can see in the RPM trace.

So I think my settings, above, work well. It looks like ~800 RPM runs the fan fast enough to keep things cool at 94F, but still lets me have a low RPM idle to make coming out on the clutch at a stop easier. And, the desired RPM increases aren't significant enough to cause problems when putt-putting around on a trail.

[Gary Lewis]

Apparently y'all fully agreed with my rationale, which is good because it appears to work.

Today I wrote that tune into the ECU and, sure enough, had to pull Fuse 10 to make the ECU forget something. (I made the keep-alive fuse #10 instead of #9, Bill.) But after doing that it started up nicely, although it was again quite lean since the computer had forgotten what it had learned.

To test that tune I warmed the engine up and then started data logging. The graph below starts with the ECT @ 196F, the A/C on Max, and the ambient temp at 94F. The vertical white line is at the point where the ECT was 209.488 and the desired RPM was 640. But at the very next data point the desired RPM had gone to 656 and the ECT started climbing, as did the desired RPM.

Ultimately the ECT stopped climbing at 225F and the desired RPM was wavering from 784 to 816. At that point I moved the truck to cool the engine down, which you can see in the RPM trace.

So I think my settings, above, work well. It looks like ~800 RPM runs the fan fast enough to keep things cool at 94F, but still lets me have a low RPM idle to make coming out on the clutch at a stop easier. And, the desired RPM increases aren't significant enough to cause problems when putt-putting around on a trail.

Also, I should have mentioned the battery voltage. It was at 13.5V at the start of that test and down to 13.2V at the end - even with the rising RPM. So it doesn't look to me like electric fans are a good idea for Big Blue.

Having said that, BB's battery voltage isn't held very high. At startup it'll go to 14.2V, but after everything warms up it drops to 13.7V. I'm running a soft-start regulator to prevent belt squeal, so I'm wondering if the another regulator would drive the alternator harder at idle.

EDIT: Here's a shot showing VBAT, and where the white vertical line is we are at the 8 minute point in the log, with the voltage down to 13.9V. But RPM is at 1800+, so it isn't low revs causing it.

[ArdWrknTrk]

Also, I should have mentioned the battery voltage. It was at 13.5V at the start of that test and down to 13.2V at the end - even with the rising RPM. So it doesn't look to me like electric fans are a good idea for Big Blue.

Having said that, BB's battery voltage isn't held very high. At startup it'll go to 14.2V, but after everything warms up it drops to 13.7V. I'm running a soft-start regulator to prevent belt squeal, so I'm wondering if the another regulator would drive the alternator harder at idle.

EDIT: Here's a shot showing VBAT, and where the white vertical line is we are at the 8 minute point in the log, with the voltage down to 13.9V. But RPM is at 1800+, so it isn't low revs causing it.

It is good to see that running the water pump a little faster helps keep the coolant temperature down without compromising driveability. Progress!....

I'm not sure what to say about LRC. 🤔

AFAIK its is only there to taper the regulators response to sudden changes, and even then just for a few seconds.

What happens if you cycle the climate control blower off and back on?

Does the voltage come back up with the blower off? Does it ramp to 14.2 over six seconds when the blower is re-engaged?

Is there something between the alternator and truck that is causing alternator output to sink over time?

i.e. can you test actual output at the stud.... or can you try switching the yellow white trigger to the battery for testing to see if the alternator will try to keep the system voltage closer to the set point?

At least this would tell you where to start looking.

Maybe the alternator is just sagging in the heat of the engine bay?

I don't know its history.

[Gary Lewis]

It is good to see that running the water pump a little faster helps keep the coolant temperature down without compromising driveability. Progress!....

I'm not sure what to say about LRC. 🤔

AFAIK its is only there to taper the regulators response to sudden changes, and even then just for a few seconds.

What happens if you cycle the climate control blower off and back on?

Does the voltage come back up with the blower off? Does it ramp to 14.2 over six seconds when the blower is re-engaged?

Is there something between the alternator and truck that is causing alternator output to sink over time?

i.e. can you test actual output at the stud.... or can you try switching the yellow white trigger to the battery for testing to see if the alternator will try to keep the system voltage closer to the set point?

At least this would tell you where to start looking.

Maybe the alternator is just sagging in the heat of the engine bay?

I don't know its history.

Yes, it is good that a little more speed for both the water pump and fan help with the cooling. I really like that.

On the alternator, I can test connecting the yellow/white wire directly to the battery, but I'm pretty sure it already is. So I may just put a volt meter on the Y/W wire and see if it is seeing what the ECU is seeing.

But I know that the voltage is coming down as I can see it on both the voltmeter from Rocketman and the aftermarket voltmeter that watches the aux battery. Rocketman set the ammeter-converted-to-voltmeter to 14.4v at the top mark and 12.8v on the middle mark, and when I start up it goes almost to the top mark. Plus, the aftermarket meter says we are right on 14v. But after several minutes of running it comes down, just as in that chart. Oh yes, remember that the Sony radio has a voltage readout, and it shows roughly what the ECU is seeing. So the voltage is coming down.

And I think it is the set point that is changing. I did some searching about that and found these posts by a couple of guys I think I recognize. One says he's a "Pedant" and the other appears to have something to say about any and every thing. But I still don't know the answer to the question.

As for the history of the alternator, if you don't know who does? I got it from you.

[ArdWrknTrk]

Yes, it is good that a little more speed for both the water pump and fan help with the cooling. I really like that.

On the alternator, I can test connecting the yellow/white wire directly to the battery, but I'm pretty sure it already is. So I may just put a volt meter on the Y/W wire and see if it is seeing what the ECU is seeing.

But I know that the voltage is coming down as I can see it on both the voltmeter from Rocketman and the aftermarket voltmeter that watches the aux battery. Rocketman set the ammeter-converted-to-voltmeter to 14.4v at the top mark and 12.8v on the middle mark, and when I start up it goes almost to the top mark. Plus, the aftermarket meter says we are right on 14v. But after several minutes of running it comes down, just as in that chart. Oh yes, remember that the Sony radio has a voltage readout, and it shows roughly what the ECU is seeing. So the voltage is coming down.

And I think it is the set point that is changing. I did some searching about that and found these posts by a couple of guys I think I recognize. One says he's a "Pedant" and the other appears to have something to say about any and every thing. But I still don't know the answer to the question.

As for the history of the alternator, if you don't know who does? I got it from you.

I'm not doubting that the voltage is dropping to 13.2 while running.

I was asking if the regulator knows that, or if the yellow wire is seeing 14+ volts at the output stud.

You say that the sense wire in Big Blue is connected to the battery in your setup. So I guess that answers the question.

So is the set point changing, or is the alternator heating up and unable to meet demand? 🤔

Is the regulator just happy to see a fully charged condition and knows it doesn't need to work the alternator any harder unless added draw starts to pull the voltage down? (13.2 V is fully charged for a 12V lead acid battery after all)

If Ford implemented the LRC regulator to keep alternators from drastically affecting smooth engine operation why would they program them to apply additional load when it's actually detrimental?

That alternator was pulled from a wreck when I noticed it looked "new".

Then it sat on a shelf waiting for a purpose in life.

I don't know how long it had been in service or anything else about it.

 

[Gary Lewis]

I'm not doubting that the voltage is dropping to 13.2 while running.

I was asking if the regulator knows that, or if the yellow wire is seeing 14+ volts at the output stud.

You say that the sense wire in Big Blue is connected to the battery in your setup. So I guess that answers the question.

So is the set point changing, or is the alternator heating up and unable to meet demand? 🤔

Is the regulator just happy to see a fully charged condition and knows it doesn't need to work the alternator any harder unless added draw starts to pull the voltage down? (13.2 V is fully charged for a 12V lead acid battery after all)

If Ford implemented the LRC regulator to keep alternators from drastically affecting smooth engine operation why would they program them to apply additional load when it's actually detrimental?

That alternator was pulled from a wreck when I noticed it looked "new".

Then it sat on a shelf waiting for a purpose in life.

I don't know how long it had been in service or anything else about it.

I will check today, but I'm sure that the Y/W wire is seeing battery voltage. And I'll also check to see that the alternator isn't getting hot. Plus I'll turn things on and off and see what the voltage does.

But I'm pretty sure it is working as designed. The regulator takes the voltage up to 14.2 to ensure the batteries are fully charged, but then drops the voltage to 13.7 after a few minutes to keep from boiling them dry.

However, one concern I have is that the reduced voltage also reduces the light from the headlights. Lamptech says "Within the normal range of supply voltage variations the light output will change by about 3.5% for a 1% change of voltage." But a bit of research seems to say that most automotive bulbs are rated at 12.8V, so while 14+ volts would give more light, 13.7v is already 7% high. And the Lamptech site says "The effect of voltage on life is much more pronounced; 5% over-voltage will roughly halve the lamp life, whereas 5% under-voltage will approximately double it."

So, maybe what I have is exactly what I need?

[ArdWrknTrk]

I will check today, but I'm sure that the Y/W wire is seeing battery voltage. And I'll also check to see that the alternator isn't getting hot. Plus I'll turn things on and off and see what the voltage does.

But I'm pretty sure it is working as designed. The regulator takes the voltage up to 14.2 to ensure the batteries are fully charged, but then drops the voltage to 13.7 after a few minutes to keep from boiling them dry.

However, one concern I have is that the reduced voltage also reduces the light from the headlights. Lamptech says "Within the normal range of supply voltage variations the light output will change by about 3.5% for a 1% change of voltage." But a bit of research seems to say that most automotive bulbs are rated at 12.8V, so while 14+ volts would give more light, 13.7v is already 7% high. And the Lamptech site says "The effect of voltage on life is much more pronounced; 5% over-voltage will roughly halve the lamp life, whereas 5% under-voltage will approximately double it."

So, maybe what I have is exactly what I need?

I understand that your coolant temps were getting high when your grandson was putting around the Church with the AC on. Is that not expected?

Did kicking the idle speed up not resolve that? Did it adversely effect driveability?

I guess I'm just confused as to why you felt that electric cooling fans were not an option because of this alternator's output.

Ford implemented the higher output 3G design because of the demands of electric cooling fans.

I would expect the alternator to be getting hot. That's why it has a big heat sink and two internal fans.

Then you point out the voltage returning to what is normal for a fully charged lead acid system after ten minutes.

Is it better to burn out than to fade away??? (Neil Young is still kicking)

Did Lamptech include any documentation as to their lamps design values?