P500 Rectifier getting extremely hot

[oakescharles]

Took my p500 out for a Cruze down the street and noticed a burning plastic smell. Upon arriving back at the house, smoke was coming out of the back of the engine. Notified the rectifier was melting the battery box. (See picture) I unplugged the battery and let it cool. Unplugged both plugs on the regulator and reconnected the battery. Then I connected the hot/ground wire. The regulator started getting hot again. I did a quick check of grounds, didn’t see anything obvious. Any thoughts? Bad rectifier? Bad ground somewhere? Short?

 

[Glock21user]

Change the rectifier.

 

[HondaTech]

Usually the rectifier is a fault if it's getting that hot. It's probably trying to overcharge the battery and building up too much heat.

Thats not a typical issue I've come across, I'd probably check the stator output as well. Just to make one of the stator legs isn't doing something crazy.

 

[oakescharles]

More info: it gets hot even when not running

 

[HondaTech]

More info: it gets hot even when not running

Possibly a battery issue then.

 

[oakescharles]

Possibly a battery issue then.

Battery reads 12.1v not running. What can I look for besides voltage when checking the battery.

 

[Remington]

Battery reads 12.1v not running. What can I look for besides voltage when checking the battery.

Im thinking the rectifier is just bad But a loose or corroded ground at the frame can also cause the issue so check those really well. What year P5 and how many miles? Im assuming u being a very early member since Christ was a foot soldier, she has some miles on it?
also, where bouts your located? Your Avitar is quite naked if you will.

 

[pappyo]

One Senior Member to another. <> With SAME DAY Membership Join

I'd be looking for a short ( Grounded somewhere it should't be ) with a ohm meter. ( continuity test )
Pinched - Worn - Over Heated- Burned - Critter chewed <> "Wire"

Charge / Check Battery
Replace Rectifier

Foot soldier?
NEED to be a Experienced Hunter for this one.
Avatar & Location Doesn't enter into the equasion.

Dec.13 2013 - ( 2014 RED P700-4 ) with low serial## - hard to find compare to the P520 "LAST YEAR" - Traded for Red 2018/P500
Honda's SXS Division was in its Infancy ( Even today take away the Electronics & Fuel Injection ) whats left 1960's engineering fairly easy to work on.
Jets & Space Travel had already Evolved

Remington :: you forgot to ask" Her Name "

Took my p500 out for a Cruze down the street and noticed a burning plastic smell. Upon arriving back at the house, smoke was coming? Bad rectifier? Bad ground somewhere? Short?

View attachment 352373

 

[oakescharles]

Im thinking the rectifier is just bad But a loose or corroded ground at the frame can also cause the issue so check those really well. What year P5 and how many miles? Im assuming u being a very early member since Christ was a foot soldier, she has some miles on it?
also, where bouts your located? Your Avitar is quite naked if you will.

Kinda what I was thinking, however I don’t like throwing parts at a problem unless I have no other choice.
15 1600 miles or so. I live in south Mississippi.

 

[oakescharles]

One Senior Member to another. <> With SAME DAY Membership Join

I'd be looking for a short ( Grounded somewhere it should't be ) with a ohm meter. ( continuity test )
Pinched - Worn - Over Heated- Burned - Critter chewed <> "Wire"

Charge / Check Battery
Replace Rectifier

Foot soldier?
NEED to be a Experienced Hunter for this one.
Avatar & Location Doesn't enter into the equasion.

Dec.13 2013 - ( 2014 RED P700-4 ) with low serial## - hard to find compare to the P520 "LAST YEAR" - Traded for Red 2018/P500
Honda's SXS Division was in its Infancy ( Even today take away the Electronics & Fuel Injection ) whats left 1960's engineering fairly easy to work on.
Jets & Space Travel had already Evolved

Remington :: you forgot to ask" Her Name "

Thanks for your insight, I didn’t check ground continuity, however it will be interesting to see the outcome.

what’s weird, it cranks just fine. There is no spark when connecting the negative battery cable back. The hot and ground wires going into the rectifier are cool to the touch.🤷🏻‍♂️

 

[Scoop]

Rectifier getting extremely hot

 

[Brmcg324]

Check the battery voltage with the engine running. If it is near 14 Vdc, most likely not a pinched or shorted wire overloading the electrical system. If the battery voltage is pulling Dow to below 12 Vdc, that may be a sign of a shorted wire. Need to check with key on and motor running to get all circuits turned on. My guess is bad rectifier, if you were able to start the engine and drive around for a while before it got screaming hot.

 

[Scoop]

Use to ride Gen 4 and Gen 5 Honda VFRs. I would regularly ride several thousand miles in the span of less than a week (sometimes 3-4 days), and all you had to worry about was oil, gas and tires.

The *only* weak point of the bulletproof VFR was the regulator/rectifier. It was so common for these to go, it was one of the few spare parts we carried with us on our trips. Damn near everybody had a spare one on hand. Best to rule that out (or replace it) before it cooks the battery. I lost count of the number of times I replaced the R/R and a battery in the parking lot of a Walmart in the middle of nowhere.

 

[pappyo]

More info: it gets hot even when not running

Key off or Key on?
To generate Heat has to be a draw. Need to track that down.
What is voltage reading when not rinning & getting hot.
So far everything points to Rectifier being Fried.

 

[oakescharles]

Key off or Key on?
To generate Heat has to be a draw. Need to track that down.
What is voltage reading when not rinning & getting hot.
So far everything points to Rectifier being Fried.

Key off 12.1, key on 12.0

 

[oakescharles]

Interesting experiment..took the rectifier to my bench. Hooked a battery to the correct polarity of the plugs on the rectifier. The battery levels dropped .7 volts and temp of the unit rose from 91 degrees to 104. Has a be a bad rectifier?

 

[Glock21user]

I have had 3 over the years on various Hondas doing the very same thing.
Hot as all get out and gets hot when not running and the key off all turned out to be rectifiers that shorted internally.
That's why I said right off to replace it, I probably could have added my reasoning but being at work doesn't always work with forum needs.

 

[Remington]

Foot soldier?
NEED to be a Experienced Hunter for this one.
Avatar & Location Doesn't enter into the equasion.

Dec.13 2013 - ( 2014 RED P700-4 ) with low serial## - hard to find compare to the P520 "LAST YEAR" - Traded for Red 2018/P500
Honda's SXS Division was in its Infancy ( Even today take away the Electronics & Fuel Injection ) whats left 1960's engineering fairly easy to work on.
Jets & Space Travel had already Evolved

Remington :: you forgot to ask" Her Name "

The question wasn't for you, it was for the OP who took no offense to it. But yes…yes location enters into the equation. Do u know what the Foot soldier phrase means?

@pappyo as your suppose to tag someone here, a senior member should know this…C’mon man! 🤣
So why would I ask her name? I need to see what she looks like first

Looks like the OP have found the rout squared to his problem now👍

 

[Remington]

Kinda what I was thinking, however I don’t like throwing parts at a problem unless I have no other choice.

Yes I feel the same and take that very approach in my trade as well. Process of elimination. as I tell the Apprentices I get….
Work Smarter Not Harder.

 

[pappyo]

OH my ! Just added to the Hunor you already started. Sorry if you took offence