Ramsair

Recently been dealing with some electrical gremlins... have done all the reading I could find on here and other places on the net in regards to the most practical way to fix or replace my alternator on my 2012 ZR1. Have been driving it for the last year and noticed when I first bought it that the Battery Voltage on the display was showing 12.8 to 13.1 and at times dropping to 12.1 for no apparent reason. Recently it dipped into the 11.7 -9 range. Then the weird stuff starting happening... slow starts with the tick tick tick and then a few tries at the button to get it to turn over - switching from seating position 1 to 2 and changing mirrors and radio settings. And then today, after a short drive my intercooler pump would not shut off (undid the battery to get it to stop). Had the battery checked, and it showed low on charge, no surprise... but they said it was a good battery. However even after a quick hour charge it was struggling. It is was 2 years old and in this heat they just only last so long... so to eliminate it from the equation, I swapped it out for a new one ... ended up going with an EVERStart Maxx T5 - Johnson Controls. On the way back from installing it, I was 12.7 - 13.0. Thinking that is still too low, (especially after all my reading on the forum) so next will be an alternator replacement. After a lot of reading online and a few key strokes, it looks like the ZR1 alt is p/n 25888947 - going to avoid the websites that have the wrong picture of our 4 up bolt config - those websites are already losers in my mind! So - for all of you that have done this replacement ... is it worth going new or finding a local alt rebuilder to do a quality rebuild or just go with a new one? My best guess that the internal regulator is not working well and will ultimately fail on this unit. That said, looks very straight forward ... just have to release the belt tensioner, pop the belt off and then remove the 4 bolts? Very little out there from ZR1 owners on this process.

By the way, I do have the LF 710 package - was on the car when I bought it and some say that the pulley config makes alt spin slower, thus less output. Car only has 15.5k on the clock. Thoughts?

As always, thanks in advance ~

Chris

Patriot Six

I just replaced my stock alternator on my boosted Z06 due to installing dual fans and having an unsteady idle voltage of around 13 volts. I replaced it with a Mechman billet 170 amp alternator and it’s now a steady 14+ volts at idle with AC on blast. Contact Bret (blownbluez06@RKTPerformance) and he can get you hooked up with what you need, if they make one for a ZR1.

Patriot Six

DC Power Inc also makes one specifically for the ZR1.

trogdor

another vote for the mechman... comes power coated and polished and great output and its a smaller case so it fit with my custom valve covers

Ramsair

Doing some research and found this about the RVC ~

http://www.teamzr1.com/ubbthreads/ub...at&Number=1062

Ramsair

So --- new battery on Monday... so far starts strong and no issues. Drove it this morning and what was strange is that the battery voltage reading showed 10.9 to 11.3 for the first 3 miles. Was parked for 5 mins and then started strong, BV read 12.5 to 12.9 for another 4 miles. Parked for 10, same result - last stop was for gas, went to start and was initially slow turn over, but started... then read 12.6 to 12.9 ... mostly hanging at 12.8 all the way home. Turned it off, started it back up and it was a strong start.

So first question is: Is 12.8 enough to keep my battery charged? Second question is for those with a LF 710 installed: Are you seeing the same low bv numbers with a stock Alt?

Had A/C and radio on the whole time - 95 degrees out


Thanks

FNBADAZ06

You check that the battery is fully charged ? If not, it's possible that the voltage is lower because it's trying to charge a low battery along with running all of your accessories ?

Ramsair

Battery was fully charged before starting the car. Is it possible for just the act of starting it and running A/C for it to show 10.9 to 11.3 for 3 miles? It did not go up on the DIC until after the second start about 5 mins later.

Thanks for the reply

FNBADAZ06

I'm in Phoenix too, and just recently replaced an alternator at the end of summer last year. The electrical load on our cars is pretty heavy, especially as it begins to get hot and the cooling fans kick on to maximum speeds for extended periods of time.

I noted that my car did the same thing following an alternator replacement....unusually low voltage readings. I tested the output from the alternator ( a brand new unit, not remanufactured) using my voltmeter and also determined that my battery was weaker than I thought. I ended up putting in a new battery and viola....everything went back to normal.

Are you tuned at all, or are you stock ?

Ramsair

Tuned by NicD - last Sept for 91 octane... car came from TX and was tuned for 93. Had CPR reinforce the bricks at the same time - car had melted the cats so went with off road X pipe - So, I have the new battery, but the Alt is stock and original. Know the DIC BV reading is not what the Alt is putting out - regulator or RVC could be bad. Will get it in for some more indepth analysis ... not my expertise.

FNBADAZ06

I had poor luck with remanufactured alternators. Seems that the bearings that are used in them are not up to snuff with high RPM engine speeds. I lost my original at 90K miles at the dragstrip, then lost a re-manufactured Autozone gold and A/C Delco doing 1/2 mile runway events.

Switched to a brand new GM unit and it's been great ever since.

Ramsair

100% agree that OEM is the only way to go, unless it would be one of these other custom built units. These are not the cars to try to go "skinny" on quality!

Thanks again ~

SIK02SS

phils C5 vette

Im glad you have this tread. I meant to start one on "what's your driving voltage" I leave mine on a battery tender when not in use so I haven't had any issues, but driving I don't think Ive seen mine outside 13sV. My other cars hang in the mid 14s.

I was also wondering if that was enough to charge the system. I really don't listen to the radio much, but always have the AC on.

Ramsair

Exactly - My 06' Z06 was always in the high 13's, so I never thought about it. Always had a little heads up when a battery was going... with this it is simply unsettling. Sub 13's and it makes me wonder how deep of a charge the battery is getting. LF 710 changes the ratios further so then you really start to wonder if the Alt mod is mandatory.

Would like a few more ZR owners to chime in if possible - take a look at your BV readings and report back ~ thanks!

SweetZO6

silvrhand

I've had a ton of problems after I added an aftermarket radio and amp.

- the charging loop for the alternator runs through the solenoid, just bypass that over to the fuse box. Heat around the headers/under the car eventually will cook a start solenoid and you'll be left stranded.
- rerun the cable from the fuse box back down to the starter.
- upgrade to mechman alternator, most ac delco are reman, and they still cost $400, and they still suck.

Ramsair

That is really good information about the charging loop. I do have headers and it is hot in AZ ... so these are all great suggestions!

Thanks

Apocolipse

The electrical in our cars is sketchy to say the least. I dont know of many that show 11.5v on a fully charged battery during acc mode

Ramsair

Just spoke with Mechman - they don't have a unit for the ZR1 ~ they also don't build their units based on Valeo parts / tech (stock unit internals).