DC Power Engineering h.o. alternator issues

You're a good dude. I've felt your pain before. Get screwed and then want to resell something that just wasn't going to be decent for someone else. Couldn't bring myself to do it. Disclaimer isn't a bad idea and sell it locally on Craigslist or something? Either way, a clean conscience(selling with disclaimer still keeps it clean, lol) isn't that bad of a trade off for a couple hundred bucks. Still sucks though.

 

250 amp alt ordered! Thanks again @BamaToy1997
I look forward to purchasing your stage 4 kit too once I get around to tearing out my rats nest of wiring and redo it all, and get a second battery.

 

Glad to see you're getting this worked out. I really don't know why they put that massive spacer where the adjustment bracket is located. With some proper measuring against the OEM alternator, they could have provided a thinner spacer and the fitment would have been great- aside from the top bracket failing at the case. I am a little surprised that the adjustment bracket still managed to break in half- it's at least 3/16" thick and the one I picked up does not look like pot metal.

Now that your going with an even larger, 250A unit, what about the adjustment bracket? Do you plan to have a larger one fabricated with larger adjusting bolt and hardware, or run with the stock adjusting bracket setup? Rule of thumb is around 1HP per 25 amps, so you're looking at 10 horsepower applied to the unit mounting hardware at full load..... I ask because I'm debating which alt size to go with myself and still have it be reliable....

 

Its the small pivot point they use on the alternator that lets it vibrate. Stop the vibrations and the lower bracket will be fine.

 

Well it seems that all other h/o alts use similar cases to the oem densos. Bama toys alts are exactly like the oem case. So same beefier support up top. I think it's the same exact size too. They're just rewound. I just got the biggest(highest rated) one he offered. So I shouldn't have any more problems. And better to have more than enough than too little. And it's cheaper than the dc alt. Only advantage the dc alt has I think would be slightly better idle output. And even more though with their higher peak rated alts.

If you end up keeping your alt, or at least sending it in for a case replacement, you might think about removing that spacer and replacing with a few stacked washers. Probly won't help the situation tho. Maybe. I never did end up doing that. But like I said in my original posts, I did remove that spacer initially when I first got the alt because it didn't wanna go in, but without it there was too much gap so I put it back in and finally got it. But that spacer can be removed with some pliers and twisting it out...

Unfortunately I don't think there's a way around this. There's really zero options for supporting the back of the case. Unless you're a master fabricator. Ha. But yes. I do believe it's all due to the singular pivot point on top. The lower bracket should be used for nothing but adjustment. Its not load bearing. And yes, I think it does cause quite a bit of vibes. I can press down on the belt and can see the whole alt skew slightly. Then pressed on the belt repeatedly as fast as I could, and it didn't look pretty. Surprisingly it looks fine when in park and revving. But I'm sure there's other factors that come into play to cause it to vibe, like engine load and terrain.

 

That makes sense, however, that adjuster and associated hardware is preventing the alternator from rotating, while keeping the belt tight at the same time. I hope you're right because after thinking about the way it's put together, it definitely lends itself to some flex with that single support where it is mounted to the face. Seems like there would be some flex there.... It's really too bad, because it seems like such a great product and has performed pretty well. Not a ton of high output options out there. Years ago, I had a Ranger with the terrible 80A alt with plugin outputs that had a tendancy to melt. The upgrade to an Explorer 130A unit was as easy as a couple bolts and plug and play factory harness. Wish this mod had been so easy!

What range of outputs did Bama offer? Is it whatever you spec as far as amperage and regulator voltage? Looking forward to seeing how it works out for ya! I'm going to replace the DC unit with something else soon, just haven't decided what with....

 

https://www.tacomaworld.com/threads/1st-gen-electrical-system-upgrade.311091/

 

Perfect, Thanks!

 

Just a little update for anyone still following...
Got Bills (legit) h.o. 250a denso replacement alternator in. Not quite as affective as the D.C. alt, as I'm still experiencing some flickering and dimming at idle (and with rpm changes) with my led bars whilst my subwoofer's going. But I'll certainly live with it no problem as I'm more concerned with reliability at this point. Not to say the 250a isn't great, but I will say the D.C. was top notch regarding performance, and hard to beat.. But their mounting system is, no bueno..

Nothing's really gonna fix the performance needs I'm looking for anyways until I get my dual battery setup installed I think. Pretty sure that'll fix all my issues once that second battery is in and isolated, which will in turn isolate all my lights and misc accessories from the main where my stereo will be hooked up to.. At least I won't have to worry about my shit breaking anymore tho!!

I did however have a hard time installing the denso alt as well. Which the D.C. alt was also a pita to fit in that top cradle as well. But this was due to the small spacer in the engine bracket/cradle(on top) appeared to have been pushed in a tad. Probably from me over tightening it in the past. So after struggling and cussing and scratching my head, I decided to file the inside of that spacer a hair, and she finally slid right in. Probably filed a lil too much off. Doesn't take much, fyi, if anyone ends up doing this(if you'd got an overly tight fit like mine was). But after I buttoned down the top bolt, she snugged up nice and tight.

Another bonus with the denso replacement, is that the lower mount on the alts case, where the tensioning bolt goes through, the hole was threaded. Whereas my oem denso was not. Which kinda always had me worried that the tensioning bolt would fall out over time(and in fact did once, when I first bought the truck). Now there's no chance of that.

 

Are you running ant caps on your amps?

 

Still following!

Trying to visualize how you threaded the tensioning assembly into the hole? It seems like there would be no way of tightening that stud down without not being able to align its hole with the adjustment bolt. Maybe I'm missing something here, but the Mean Green alternators are the same way unless you drill out those threads.

Thanks for the updates. Sounds like you're most of the way there but I'm surprised the lights still flicker. I believe you upsized the charge and ground cables accordingly?

 

Yeah a cheap $30 one iirc. Previously didn't. But it was on sale when I purchased a better amp. No idea if it's helping but doesn't seem to be. It is rated properly for the amp tho. But I've read mixed reviews about them not doing squat and I'm leaning towards those opinions. Was gonna remove it.

Yeah I had to think about that one too when I discovered the hole was threaded. I just removed the long adjustment bolt, then threaded in the stud through the tensioning bracket and case mount till it was tight, then backed it off one turn to align the threads on that stud for the adjustement bolt, then threaded in the adjustment bolt from the side. Then put the nut on the stud as well after belt tension was set for extra precaution, even though it doesn't help tighten down the case mount to the bracket. Which I'm not really sure if it matters. Because I'd like to think that the lower case mount shouldn't be tightened down to the bracket via a blank hole which would allow that to work. That way if/when it loosens up, it can slide on the bracket and only affect belt slippage rather than putting force on the lower bracket and breaking it. Because like I said before, I believe it's sole purpose should only be for adjusting the tension. Which is probly why I had issues with it breaking.. But my oem alt also had a blank hole just like the D.C. did... So I'm not sure which is supposed to be the "proper" method. But seems to me this may work out better.

If anything, I'll have to adjust the belt tension more often maybe. We'll see.. But I'm fine with that as long as it doesn't break anything. But doesn't make sense to me why the adjustment bolt wouldn't be enough to hold it.

 

Does anyone know if that hole is supposed to be threaded? Or if it varies via changing years? Curious now. Wondering if someone drilled the hole in my oem alt.

Missed this. But yes. Big 3.

 

I have seen some threaded and some not. I honestly do not know the rule/option on that.
I am surprised as well to see that you have flickering still remaining. Can you fill in some questions?
1. What is the engine idle with no load?
2. What is the engine idle under load?
3. What is the voltage with no load (measured at the battery posts)
4. What is the voltage under load (again, measured at posts)
5. Can you list the details on the different loads that you have? (Item name, estimated amperage draw)


You mentioned that you do have a capacitor? With a cap I REALLY find it odd that you have a flicker because the cap should easily be capable of covering your amp load. What is the brand/size of the cap? I can't remember the brand name of mine, but it is a 2 farad.

 

Yeah it's kinda minimal dimming and only with the subwoofer going iirc. Which is kinda expected with everything on one battery. I didn't mean to sound like I was throwing this alt under the bus or anything. Because it certainly puts out. Driving at speed it performs great with the stereo(very very slight dimming, hardly noticeable). And at idle it works great until i crank the stereo up. Capacitor is a Belva BB1D 1.0 farad. My amp is 1200w. So a little under powered. But I didn't even notice any change with it installed.

Flickering only occurs with rpm changes at low idle. From a stop or creeping and giving it gas, with no stereo.. So that's the one thing that caught me off guard. The way I have my light bars wired up probly isn't the best as they are grounded through the headlight wiring (as they are wired in series to high beams, via relays for power but activated and grounded via the negative switched system, iirc). As that was the only way to do it easily. I plan to redo all that wiring once I get into a dual battery setup and find a better activation source via the high beams. But again, I didn't have any flickering with the DC alt, so I had assumed my wiring was not a factor. So I am curious if there is in fact a chance it's something else on my end playing a part, or if it's simply the need to run an isolated dual battery setup.. Which is what I'm leaning towards believing so I'm not really worried about it atm.

But I have done a few voltage tests for ya anyways and was as I expected, which shows it's performing like it should as far as voltage output goes.. Still kinda new to testing electrical systems, as far as the more advanced testing stuff goes. But gonna purchase a clamp meter for testing amperage on the alt as well as the light bars.

idle/voltage tests:
1. What is the engine idle with no load?
700 park. 590 in drive.
2. What is the engine idle under load?
same. Slightly lowers, then compensates. But the load change is audible.
3. What is the voltage with no load (measured at the battery posts)
14v
4. What is the voltage under load (again, measured at posts)
13.95
5. Can you list the details on the different loads that you have? (Item name, estimated amperage draw)

accessories of note:
42" light bar- 21.6 amps
20" light bar- 20 amps
dual electric fans for condenser when ac is on- 5.6 amps
1200w amplifier
aftermarket head unit
tpms
dash cam
All I can think of as far as constant accessories go. So yeah, not much.

I previously had more off road lights installed. But my current draw of 500w just from the two is pretty similar to my previous setup. These lights seem to put quite the load on the system though just by themselves and an audible change in the load can be heard for sure. And as previously stated, I will have lots more to come. As well as more subs and larger amp, eventually.

So my question for you, is should I be concerned about anything since you're asking? Or should I not bother delving deeper into diagnostics, and focus on that dual battery setup and isolating those accessories?

 

I guess that threaded hole is not unusual. When I spoke with the folks at Mean Green, they said that their unit comes threaded, and drilling out the threads is perfectly acceptable. Seems like an odd design when the OEM unit is not threaded. After thinking about it a little, I will say that threading in that stud for the adjuster assembly would defeat the purpose of the nut which serves to tighten that stud enough to lock the adjusting bolt into place. With the stud threaded into the alternator, there is no way the nut can tighten the assembly effectively. That stud needs to sit freely through that hole until the nut is tightened thus tightening the entire assembly- in my opinion...

Unless Toyota revised that adjusting bolt/locknut assembly, that threaded hole may have something to do with the manufacturing/machining process of the case. From experience with aftermarket parts, I've learned to expect the unexpected.......

 

Yeah you're right, but the question is, is that assembly heavily reliant on that lower tensioning stud to be tightened to the bracket? Or is the adjustment bolt (as well as the top bolt) sufficient to hold it in place. I guess time will tell. Now that I think about it more too, I am kinda concerned and will for sure keep an eye on it. If anything I'll just drill the hole out. Easy fix.

 

Oops. Quoted without a reply....
How did the unit fit up to the adjusting bracket? Better than the DC Power Alt?

 

Yep. No issues there. I think that spacer that dc used was just too thick. And I think I stated before, if you're gonna keep the dc, you might consider taking that spacer out and using a different universal spacer from a hardware store, or stacked washers.
Or, have you tried slightly loosening the bolt on the block, then tightening it back fully afterwards?

 

I'm sitting on my hands trying to decide which alternator to get, and leaving the small crack in the adjuster bar as-is lol. I think it's been that way for some time.... At this point, I have a replacement adjuster bar from Toyota sitting on the work bench. This isn't my daily driver, so been taking my time deciding what to do. Curious to see how your new alternator works out. You're setup will put it through its paces!