What have you done to your Land Cruiser this week? (28 Viewers)

[1911]

Yes, but you can definitely smoke your system with too many amps as well.

The great thing about an alternator (as opposed to a generator) is that it will only put out the actual amps needed or drawn by the stuff in the system, up to the rated amperage. The one thing that would be smoked in a 40 is the ammeter, assuming that any secondary wiring you added for a winch and etc. is up to the task. I have been running a 200-amp alternator for 11 years now, and it is great for my purposes. I did replace the ammeter in my instrument cluster with a voltmeter, and upgraded my battery, starter, alternator, and ground cables to much heavier gauge than stock.

 

[fj40fillet]

Yes the voltage regulator limits the voltage. But if the alternator is not producing to keep up with the demand of everything drawing in the vehicle the regulator can't regulate what's not being produced. The alternator works off engine RPM. This why my 68 the headlights dim and heater blower slows down at idle.

Thx...

 

[secretsquirrel]

borrowed a part measured it. made a die. MADE IT BEEEEEP!

 

[h82crash]

Yes the voltage regulator limits the voltage. But if the alternator is not producing to keep up with the demand of everything drawing in the vehicle the regulator can't regulate what's not being produced. The alternator works off engine RPM. This why my 68 the headlights dim and heater blower slows down at idle.

Yes, you got it. For others to better understand, the lights dim because at idle, a particular alternator produces less than battery voltage, so your lights at idle are running on ~12.6v. Once the rpm increases, the voltage goes up and is regulated between 13.9v to 14.5v and lights go brighter.

The great thing about an alternator (as opposed to a generator) is that it will only put out the actual amps needed or drawn by the stuff in the system, up to the rated amperage. The one thing that would be smoked in a 40 is the ammeter, assuming that any secondary wiring you added for a winch and etc. is up to the task. I have been running a 200-amp alternator for 11 years now, and it is great for my purposes. I did replace the ammeter in my instrument cluster with a voltmeter, and upgraded my battery, starter, alternator, and ground cables to much heavier gauge than stock.

All very good upgrade measures. I will note, however, current is dependent on the load and not what the source can supply. So, your first sentence is true of all electrical sources.

 

[d6crawler]

Yes, you got it. For others to better understand, the lights dim because at idle, a particular alternator produces less than battery voltage, so your lights at idle are running on ~12.6v. Once the rpm increases, the voltage goes up and is regulated between 13.9v to 14.5v and lights go brighter.



All very good upgrade measures. I will note, however, current is dependent on the load and not what the source can supply. So, your first sentence is true of all electrical sources.

Exactly that. You can draw too many amps right out of the battery with no alternator present and smoke the system. Now if you have a bunch of demand and the wire from the alternator to the battery (and anything in the path e.g. the ammeter) are not up to the task then you can smoke all of that too. This is also why modern cars have some kind of fusible link in that mix to keep your vehicle from catching on fire. There was one of these fires featuring a modified jeep down the road from me. Burned the house down.

 

[1911]

I will note, however, current is dependent on the load and not what the source can supply. So, your first sentence is true of all electrical sources.

True.

When I began driving, my cars and bikes all had generators, not alternators. When I did a lot of highway miles, the battery would boil off the water in the cells over time from too much voltage; it was hard (especially on motorcycles, where the rpm varied a lot) to adjust the voltage regulator to a range where it would charge the battery around town but not boil it off on the highway. When alternators became more prevalent, they were a godsend.

 

[Engineer8000]

A generator can be regulated in the same way an alternator can, by controlling the field voltage. The chief advantage of an alternator is that the output is generated in the stator not the rotor.

 

[John in Utah]

Noticed a read stain on the back of the block ... coolant seeping out the back of the head . Pulled everything apart today and the old fiber head gasket is torn at the back. Of course the precups are all cracked and the head has classic 3B cracks between the valves at every cylinder too

Funny thing is I just got back from 500+ miles of driving to Colorado and back and the truck did great up the mountain passes, and never even tried to get hot. The 3B is tough.

Thinking I will just throw new precups in it and an MLS gasket and see how it does

 

[steveola]

Noticed a read stain on the back of the block ... coolant seeping out the back of the head . Pulled everything apart today and the old fiber head gasket is torn at the back. Of course the precups are all cracked and the head has classic 3B cracks between the valves at every cylinder too
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Funny thing is I just got back from 500+ miles of driving to Colorado and back and the truck did great up the mountain passes, and never even tried to get hot. The 3B is tough.

Thinking I will just throw new precups in it and an MLS gasket and see how it does

Is that a crack between the intake and exhaust valve or just the casting?

 

[John in Utah]

Is that a crack between the intake and exhaust valve or just the casting?

Definitely cracked. Pretty common with these

 

[rkymtnflyfisher]

Stuff.

 

[-MaTTi-]

Definitely cracked. Pretty common with these

And harmless.

 

[steveola]

Polished a manifold then ate some Polish sausage.
Cheers
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Where did you find that glass? Very nice.

Definitely cracked. Pretty common with these

Man, these are really tough for sure.

 

[1911]

A generator can be regulated in the same way an alternator can, by controlling the field voltage. The chief advantage of an alternator is that the output is generated in the stator not the rotor.

Possibly the technology for controlling the field voltage was primitive in the 1940's - 1950's? All I'm saying (from personal experience) is that generators from that vintage were a PITA in everyday real-world use.

 

[swelltimes]

Closing in on the replacement of rear sill and rear quarters. It feels like we're making pretty steady progress, with 1 - 2 sessions in the shop a week. Getting fired up to drive the truck again soon, and will never get tired of seeing my dad smiling and getting fired up about the project.

 

[graham5david]

It's the little things. New gauge cluster screws. Added a cup holder. Washed it. Pretty productive day.

 

[d6crawler]

Possibly the technology for controlling the field voltage was primitive in the 1940's - 1950's? All I'm saying (from personal experience) is that generators from that vintage were a PITA in everyday real-world use.

The amperage is the issue combined to some extent with RPMs. Then add in modern expectations and accessories. I have a m37 generator that puts out plenty of juice so you can run the truck and a military radio. I also have an old Austin Healey and you don't want to run the wipers, lights, and heater at the same time. You will run the battery down and be stuck on the side of the road. The only other thing you *could* turn on assuming you have one is the optional radio. Note the Healey also came equipped with 2 fuses worth of protection for the circuits. Alternators put out plenty of amps at low rpms unless you have a high rpm motor and then you need to step down the pulley to keep from over-revving the alternator with the result of less amps at idle.

 

[FJBen]

Stuff.
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I really wish your pictures weren’t so bad and blurry. Looks like beautiful scenery up there.

 

[Chungas Revenge]

Added a sliding alternator tension kit from Vintage TEQ.

 

[1911]

I also have an old Austin Healey and you don't want to run the wipers, lights, and heater at the same time. You will run the battery down and be stuck on the side of the road. The only other thing you *could* turn on assuming you have one is the optional radio. Note the Healey also came equipped with 2 fuses worth of protection for the circuits.

I feel your pain with British cars; when I was younger I had a Sunbeam Alpine and a BSA motorcycle.