New 7.3L Ford gasser

[DanStokes]

Thanks, man. I've been lurking for a while. I taught Automotive Technology for 24 years, so when I see a topic that could use some Instruction Dust I like to throw a sprinkle or two on top.

Just a friendly warning - you're likely to get hooked! But welcome for sure.

Dan

[Gateclyve Photographic]

Alternator drive couplers, as installed on the lower alternator, have been around for years. Gates video from the You Tube. Watch the motion of the drive belt on the solid drive pulley compared to the drive coupler installation.

Informed speculation on my part, part a. - the reason for two alternators could be that the engine would be expected to operate at low RPM for fuel economy and emissions reasons. A two-alternator installation would divide the work required to charge the battery, (batteries), at low RPM.
Informed speculation part 2 - This engine might find itself installed in front of a wide-ratio ten-speed auto. The trans could have a couple very deep ratios for heavy load/stop-and-go driving while still allowing a decent highway cruise RPM. The lower gear ratios could be ignored for low-load operation. Mercedes has done this for with many applications with their automatics.

I also seem to recall seeing somewhere some literature on a twin alternator application for ambulance conversions, which would have significant variance in electrical demand. Don't know why I didn't recall this when we started speculating on the second dynamo.


Anyone remember the hype about the two-speed accessory drive which Ford announced for the 5.0 Mustang back in the mid-1980s, but then cancelled for some reason. It was supposed to be both a fuel saver and a horsepower-loss reducer.

[RockJustRock]

Maybe it's a Car Audio thang.

[Guy From Iowa]

I also seem to recall seeing somewhere some literature on a twin alternator application for ambulance conversions, which would have significant variance in electrical demand. Don't know why I didn't recall this when we started speculating on the second dynamo.


Anyone remember the hype about the two-speed accessory drive which Ford announced for the 5.0 Mustang back in the mid-1980s, but then cancelled for some reason. It was supposed to be both a fuel saver and a horsepower-loss reducer.

The main reason for two alternators is heat. At low crankshaft speeds and high electrical demand an alternator runs at a high internal temperature because the cooling fan on the alternator is turning slowly. Two alternators running at half-load each do not generate as much internal temperature at the same speed and load. Technically, a manufacturer could take the rectifiers and regulator out of the alternator case and mount them in a remote location and/or give them their own cooling fan, but it's less expensive to divide the load between two units.

[Deaf Bob]

The main reason for two alternators is heat. At low crankshaft speeds and high electrical demand an alternator runs at a high internal temperature because the cooling fan on the alternator is turning slowly. Two alternators running at half-load each do not generate as much internal temperature at the same speed and load. Technically, a manufacturer could take the rectifiers and regulator out of the alternator case and mount them in a remote location and/or give them their own cooling fan, but it's less expensive to divide the load between two units.

Buddy put 2 alternators on a 455 Olds powered lifted Jeep.. One battery/alternator ran the Jeep, the other ran the lights and stereo
Talked him into one alternator and 2 batteries with an isolator. I ran the same set up for a bit on my flatbed to keep my winch and boom battery charged
Guess I'll try the 2 alternators next. I think isolators charge slowly.. Good for RV's deep cycle batteries

[Guy From Iowa]

Buddy put 2 alternators on a 455 Olds powered lifted Jeep.. One battery/alternator ran the Jeep, the other ran the lights and stereo
Talked him into one alternator and 2 batteries with an isolator. I ran the same set up for a bit on my flatbed to keep my winch and boom battery charged
Guess I'll try the 2 alternators next. I think isolators charge slowly.. Good for RV's deep cycle batteries

I own several 'multi-battery' vehicles. I use the Blue Sea Automatic Charge Relay. It charges the start battery first, then charges any others in the system. Keeps the start battery from discharging even if other batteries run down. Also has status LED's to watch how it works.

https://www.bluesea.com/support/articles/57/Automatic_Charging_Relay_-_An_Alternative_to_Multiple_Output_Charging_Systems

Somewhat different than the usual 'battery isolator' installation.

Our sailboat has an Optima Red Top for start battery and two Optima Blue Top batteries for the house bank. It also has a solar battery charging system as well, but that is another deal entirely.

[BBR]

You guys kill me.

The most exciting powerplant news to come out of Ford in years and you are hung up on it having 2 alternators.

I am DYING to see this thing swapped into basically ANYTHING other than a truck!!!

Carry on.

[chevybuytroy]

Those that work them daily. are not having such luck long term.
oiling issues. and sludge, and timing chain and phasers issue.
time is money. a business that has units in a shop is not making money.
a Keep It Simple Stupid large cid. pushrod engine. is stone simple.
The fact that you tow in the hills with no trailer brakes. is all I need to know.
Good day.

I’m a Chevy guy all day long but working at a ford dealership, the 3.5 eco boost is a great engine. Sure I’ve done timing chains but you see that on other engines also. If I ever had to buy a ford, it would be the eco boost. For the most part the only time I see these trucks are for recalls and just general maintenance. This engine is good for whatever you throw at it

[chevybuytroy]

You guys kill me.

The most exciting powerplant news to come out of Ford in years and you are hung up on it having 2 alternators.

I am DYING to see this thing swapped into basically ANYTHING other than a truck!!!

Carry on.

I assumed 2 alternators were on it cause the diesels were built the same way. I was off on that one. I like guy from Iowa’s response better. Because science...

[Tubbed Pacecar]

Well, howz about in an OLD truck that it was never available in??

You guys kill me.

The most exciting powerplant news to come out of Ford in years and you are hung up on it having 2 alternators.

I am DYING to see this thing swapped into basically ANYTHING other than a truck!!!

Carry on.

[BBR]

Works for me!!

[AndyB]

You guys kill me.

The most exciting powerplant news to come out of Ford in years and you are hung up on it having 2 alternators.

I am DYING to see this thing swapped into basically ANYTHING other than a truck!!!

Carry on.

Screw that. I'm waiting to find out if they overbuilt it to a reasonable degree so that you can slap a pair of turbos on it and start removing LS's from Fox bodies!

[Tubbed Pacecar]

**The fact that they intend to use it in trucks from 3/4T on up into the heavy truck line would be an indicator that it should be pretty stout......but remember, they don't rev big trucks to 7, 8, or 9K RPM......
But as a motor for a daily driver, or a truck you may want to use to drag a trailer, etc, I bet it will be fine.

[Guy From Iowa]

Interesting background on the new 7.3 -

https://finance.yahoo.com/news/why-ford-made-7-3-211700404.html?.tsrc=daily_mail&uh_test=1_02

Here's another consideration or two. A pushrod V8 is much easier to service and repair, making for faster and cheaper turnaround in the shop. That's a big consideration for working vehicles. Ford gave themselves a big black eye with poor serviceability in the recent past. Like - needing to remove the cab from the frame for top-end service of the OHC 4.6 and 5.4 V8's.
Also - the up-charge for diesel engines is a big deal nowadays. The DEF requirement is problematic for drivers in the northern half of North America. Avoid those with a big-displacement pushrod V8 for those applications.

[Russell]

Screw that. I'm waiting to find out if they overbuilt it to a reasonable degree so that you can slap a pair of turbos on it and start removing LS's from Fox bodies!

I hope there is some way to control this engine that doesn't require are $1500 control pack from Ford in swap car.