A 20A voltage regulator upgrade for a 16HP Briggs & Stratton engine

[Uncle Vin]

Here's the conservative maximum ampacity of different sizes of copper wire:

18ga: 10A
16ga: 13A
14ga: 17A
12ga: 23A
10ga: 33A

I don't know but I've been told that the 16HP B&S V-Twin in my Max II had a 16 amp regulator. This implies that the wiring is 14ga. If you install a 20 amp stator and regulator, and you plan to use all that current, then you should probably make sure the wiring is 12ga.

I was looking at the shop manual after I posted. It's not just as simple a changing the stator and regulator. In addition, the flywheel must be changed as well, because the generation of current is a function of the stator [I]and[I] the number of magnets on the flywheel. The manual specifically says this. To sum up, in order to upgrade to 20 amp, you must: a) change the stator; b) change the flywheel; c) change the regulator; and d) rewire the machine. Any other comments would be helpful. Uncle Vin

[6X6]

Hi:
Well, if I understand the initial post, the Idea is the 20A Regulator/Rectifier will not burn out under sustained load as easily as the original. Replacing the Stator coil to a heavier unit would also be more durable but the magnets are also needed to make the 20A available. Without it the other parts will not be able to put out a full 20A. Rewiring the machine is necessary only from the Regulator to hot (+), the ground will be plenty beefy enough because of the starter. Any other rewiring would only be if you are changing/adding something. (Higher power headlight, Beef up headlight wires (Including hot to switch and ground) etc... (This is ASSUMING the 20A Regulator is the same plug as the stock)

[Roger S]

Great research on the subject. I suspected the flywheel was different. For a 4 amp increase, it sounds like a waste of time and $. I wonder why the original poster had regulator problems in the first place.

Now, if you could adapt a 23hp 20-50 amp system to the earlier blocks, that might help justify the cost. I think the engine block is different where the stator bolts on. Well, just buy a bare block for a couple hundred and put all the 18 hp parts on it with a set of intek 44 pistons for flat tops. Oh the 16 hp? crank, it would need a long rod and I don't know what piston, it would be like a 16 with a huge overbore. Oh, just buy the bigger crank for $150

On a more serious note, maybe see if the stator could be adapted to the earlier blocks. I have a small alternantor from a '70's datsun I would hang on some where. Otherwise, I'd live with the 16 amp system that's worked fiine for a decade. I guess it helps to have somewhat of a real battery size in the argo instead of a lawn and garden battery.

About the magnets in the flywheel, reminds me of the old GM alternators. The only difference in them was the size of the rotor windings (magnet). The stator, diodes, and regulator were all the same.

[Uncle Vin]

Great research on the subject. I suspected the flywheel was different. For a 4 amp increase, it sounds like a waste of time and $. I wonder why the original poster had regulator problems in the first place.

Now, if you could adapt a 23hp 20-50 amp system to the earlier blocks, that might help justify the cost. I think the engine block is different where the stator bolts on. Well, just buy a bare block for a couple hundred and put all the 18 hp parts on it with a set of intek 44 pistons for flat tops. Oh the 16 hp? crank, it would need a long rod and I don't know what piston, it would be like a 16 with a huge overbore. Oh, just buy the bigger crank for $150

On a more serious note, maybe see if the staor could be adapted to the earlier blocks. I have a small alternantor from a '70's datsun I would hang on some where. Otherwise, I'd live with the 16 amp system that's worked fiine for a decade. I guess it helps to have somewhat of a real battery size in the argo instead of a lawn and garden battery.

I know that some members had installed an alternator onto their machines, but I have never seen one installed on a Max IV with a Vanguard. I would like to. Once an alternator is installed, heating the cab becomes easy, as well as running all sorts of power-draining accessories. I wish someone would post a how-to on this subject [hint]. Uncle Vin

[jerseybigfoot]

Here is a Max4 with a 18 opposed and alternator. You would need the flywheel PTO, pulley and belt for the Vanguard.

[Uncle Vin]

Here is a Max4 with a 18 opposed and alternator. You would need the flywheel PTO, pulley and belt for the Vanguard.

That's a slick set-up. But I have two questions: First, where could I get flywheel pully (PTO, etc) to affix to the engine? Second, do you find that the alternator places a substantial drag on the engine so as to significantly reduce engine power? Thanks Jersey. Uncle Vin

[jerseybigfoot]

I found a PTO kit on ebay for $10 two years ago for my Vanguard in my bigfoot. No problems handling the load.

[Uncle Vin]

I found a PTO kit on ebay for $10 two years ago for my Vanguard in my bigfoot. No problems handling the load.

I looked on ebay and googles it. No luck. I don't have a part numer.

[6X6]

I looked on ebay and googles it. No luck. I don't have a part numer.

Try a small engine/power equipment shop, one that deals with used stuff if possible, but at least has been around a while. You may be able to find a pulley that will work. Most likely you will have to drill mounting holes, but someone who's equipped to do precision work should be able to do it. If you're up my way Newburg Power has darn near EVERYTHING in used.

[Roger S]

Briggs makes a spacer and pully.. I guess you lose the pull start though. I've slept since I last saw the argo vanguard alternator kit, but that seems the way it was.