100 series / lx470 alternator replacement quick tips no pictures (1 Viewer)

[SlowBuild]

Thanks for the advice.

I just attempted this replacement but the 12mm mounting nut is seized on the alternator. It’s starting to round over even with lots of PB blaster and lots of waiting. So I buttoned it all back up and I’ll order new hardware before I reattempt. I’m paranoid about shearing off that stud.

@Miljack ’s saga is in my mind and I want to take it as slow as can be. Also, putting it all back I turned the nuts tight then got out my torque wrench and looked up values. Only 29 ft lbf on the 14mm alt bolts and 13ft lbf on the 14mm vane pump bolts. Pretty light! I’m sure I’m over so I when I redo this maybe next week I’ll keep that in mind and also maybe apply some anti seize so I don’t end up with them bonding in place.

 

[hickuptruck]

Yeah when I did mine, previous owner had a TB job at Toyota dealership. The bolts were all so tight I had to take an impact to them. The alternator bolt I for sure thought was going to snap because I could see from the alternator case, that it was so tight it cracked

 

[smug01]

Thanks for the advice.

I just attempted this replacement but the 12mm mounting nut is seized on the alternator. It’s starting to round over even with lots of PB blaster and lots of waiting. So I buttoned it all back up and I’ll order new hardware before I reattempt. I’m paranoid about shearing off that stud.

@Miljack ’s saga is in my mind and I want to take it as slow as can be. Also, putting it all back I turned the nuts tight then got out my torque wrench and looked up values. Only 29 ft lbf on the 14mm alt bolts and 13ft lbf on the 14mm vane pump bolts. Pretty light! I’m sure I’m over so I when I redo this maybe next week I’ll keep that in mind and also maybe apply some anti seize so I don’t end up with them bonding in place.

I have a 2006 as well and seem to have a stuck 12mm nut on the alternator as well. Seems the later alternators have the extra 12mm nut to a stud above the 14mm bolt and nut from the earlier models. Did you ever figure out the 12mm seized nut? I am stuck with the same issue. Mine seems to spin the stud with a lot of friction but the nut itself is seized to the stud.

 

[Niko1]

Removing the alternator is pretty easy on 1998 land cruiser. Attack from the bottom and you will not have to take anything off. I would recommend pulling the power wires off and out of the grommets up near the upper radiator hose so the alternator will hang down further thus gaining access to the wire connectors on the alternator once free. Of course, put them back in when alternator is installed.
This was very easy....15 min removal. Removing wires from connectors was the most tedious part.
I'm having Ace Alternators (Yucca Valley, CA.) rebuild mine. They sell a killer portable welder and remanufacture the best alternators, custom, etc..

 

[tmoore41]

Same as above. Thank you for the awesome information. Probably saved $1000 even with purchasing the reman from Toyota. I wish I would have followed the OP's steps regarding the radiator hose and power steering when I started. These are really easy to do and made it MUCH easier to work with. I did take it off and put it back on from the bottom (still had to work from top some...) and did not have to completely remove the air intake or the coolant reservoir.

FYI - Toyota dealer would not accept the rebuilt Denso that I removed as a core because it was not an original Toyota part (even though it was Denso). Everything seems to be working fine on mine now. I did have the VSC lights come on and off a couple of times in the first few miles of driving. I am wondering if this is due to some sort of re-calibration? Also, I still have obtained an FSM yet. Any chance of adding the torque specs for the alternator and power steering pump?

 

[cmw]

Just did this on my '99 LC

Took a couple of days to find a rebuilt alternator in-stock at a decent price. Will spare you all the details of handling three 100amp "direct fit" alternators over three days and summarize.

Ultima from O'Reilly's: Boss for attaching the wiring bracket was tapped for the original size bolt. More crude looking case - mating surfaces of the mounting flanges not machined. Cheesy looking connector socket. Chunky rough lacquer on stator and it looked like the entire rotor (including the fan) had been dipped in lacquer after assembly. Smaller than stock pulley.

Duralast from Autozone: Boss for wire bracket was drilled and tapped smaller than original (M5 .80 fit). Proper looking case with machined mating surfaces, good looking connectors and apparently selective use of lacquer on internals. Proper size pulley.

Neither unit had the supplemental "Rear end cover" #27039 and I didn't move the one from the dead alternator ~ hope I don't regret that later.

Important details for next time:

• Absolutely immediately obvious that the power steering pump pulley had to come off.
• Could not get the alternator out without removing the radiator hose. Not from the top or the bottom. NFW - No Way. Honestly may have spent hours proving this to myself. Took out the radiator hose and squeaked it out from below.
• Disconnected the cable straps from the inner fender to provide slack in the wires while positioning the alternator to carefully work on removing the plug - very gingerly pried out with the back of the alternator facing down.
• Disconnected the output wire from above, rear connector from below.
• Will cut the cable strap away from the alternator next time and replace it rather than trying to worry it out - same with those on the inner fender.
• Had a replacement plug in case the one on the wiring harness broke (virtually guaranteeing that it would not).

No fun the first time through but could probably do the next one comfortably inside of two hours.

Planning to rebuild my Denso core.

 

[vizslagold]

quick tip- i find it helpful to use a heat gun to warm up the plugs before attempting to disconnect them. i haven't replaced the alternator on my lx yet, so i can't speak to the available access and getting a heat gun in there. i've used a heat gun to ease disconnecting the electrical connections when replacing o2 sensors and spark plugs on my 04 lx, with low ambient temps. it saved me a lot of time with the plug wires. it's also helpful when dealing with brittle plastics on german autos...i.e. changing a camshaft sensor when it's 12 degrees outside without breaking the clip. dielectric grease, silicone grease the new connections.

regarding a broken bolt, abscent a welder or space for jam nuts, has anyone tried hammering a triple square impact socket onto the broken bolt? then heating the aluminum, not the bolt.

i've dealt with a lot of frozen bolts on my lx now. sometimes it's helpful, after applying a ton of heat, to just come back the next day after everything has cooled down. i had a hell of a time dealing with a front diff fill bolt. i applied a ton of heat, and used a hammer and chisel to remove the rounded off hex fill plug. no joy when it was hot. i came back the next day with the hammer and chisel, with it cold, and it broke free straight away. fyi, welding a hex socket to the plug is the best way to deal with the plug- but i didn't have a welder.

dont use the reverse spiral tap things. if they snap off, you need to grind them out with carbide...cobalt hss bits won't touch them. just drill the broken bolts out.

if the bolt doesn't turn right out, turn it back down, then loosen, tighten, loosen, as many times as necessary to walk the bolt out. it's easier than drilling the bolt out.

 

[JohnGKTR03V]

I have a 1999 lx470 (usa). It looks like I might need a new alternator. My shop manual shows diagrams of both an 80amp and 100amp alternator. Does anyone know which one they used on the 1999 lx? John

 

[flintknapper]

I have a 1999 lx470 (usa). It looks like I might need a new alternator. My shop manual shows diagrams of both an 80amp and 100amp alternator. Does anyone know which one they used on the 1999 lx? John

100 amp (US market)

 

[JohnGKTR03V]

Thank You

 

[boma23]

Great write up by everyone. Am now more prepared but also terrified of seized bolts... I'm on a tiny island with no good mechanics and no welder. Those sort of situations can ground me for weeks.

I just bought 2 new alts at home in UK, one for the 100 and one for my old diesel Hilux Surf, but Airport security decided to take the 100 alt off me as 'dangerous goods'. (The surf alt went through in the hold no problem ). So now I just bought a brush kit from Amazon for $30 with decent reviews, as my symptoms seem like replacement might fix the alt issue and keep the original. Does anyone have any experience with them? Am worried that even after getting the alt off replacing brushes O might have some surprises in store.

I'll be doing the Surf first and getting that running, as that's by far an easier alt to do, before tackling the hundy... Wish me luck!

 

[boma23]

In fact, the bigger question is for those that know this alternator:

Is it possible to change the brushes in-situ?

Attached is picture of the brush assembly ordered.

 

[cmw]

If you mean replace the brushes without pulling the alternator - no way.

Can't imagine even getting the rear cover off without removing the alternator.

Soak every connecting part with ATF/and or your favorite quality penetrating oil several times in the days leading up to the job ~ heat-cycling helps too. If things are really rusty I like to give them a few raps with a hammer along the way as well.

Clean everything well and use dielectric grease and anti-seize liberally during reassembly.

 

[boma23]

So getting the Alt out wasn't an awful job - 3" lift on mine just meant I needed a stool for working from the top, despite being 6'1", although the trade off was that I didn't need ramps when attacking from the bottom.

Personally, I removed the airbox and associated chambers. I didn't bother removing the rad hose, as once the PS pump was off and moved out of the way, the alt easily came off and could be pulled up and passed the hose with just a small amount of squeezing past. Unclipping plastic loom and hose holders from underneath the wheel well was much easier once I realized they were actually there and accessible underneath the thick layer of underseal! The alt bolts were all easy with a long socket or breaker bear. The clip on the rear was brittle enough it snapped the clip on one side straight away though.

Anyhow.... I was convinced mine was going to be brushes due to the intermittent charge /voltage light over the last few weeks so was expecting crumbling stumps of carbon. However, once off from the Alt, they looked only halfway worn down their entire length, still with a decent contact patch - no visible arcing etc. So for that reason, despite cleaning and fitting the new bushes, I have not so far put the alt back on until I can bench test it (nearest place that can is on the next island along).

Would that be normal, for the bushes to need replacing way before the end of their physical length? I was thinking that maybe weak spring pressure as they wear might be the cause of charge of failure before they actually wear out?

Or do I just order the voltage regulator now ASAP and get that fitted as well before reinstalling...?

Vehicle is 2000, and in otherwise great shape being a low mileage JDM with only 130k kms on the clock, and no corrosion.


This is what the old ones looked like:

 

[cmw]

Those look awfully good for bad brushes.

 

[hoser]

Minimum exposed length for the brushes is 1.5mm. Problem is not the brushes themselves. I would look very closely at all the wiring from alternator to the fuse holder at the positive terminal.

 

[boma23]

Those look awfully good for bad brushes.

That's what I thought!

 

[boma23]

Minimum exposed length for the brushes is 1.5mm. Problem is not the brushes themselves. I would look very closely at all the wiring from alternator to the fuse holder at the positive terminal.

That's a great call.

 

[ibrahim83]

Great write up by everyone. Am now more prepared but also terrified of seized bolts... I'm on a tiny island with no good mechanics and no welder. Those sort of situations can ground me for weeks.

I just bought 2 new alts at home in UK, one for the 100 and one for my old diesel Hilux Surf, but Airport security decided to take the 100 alt off me as 'dangerous goods'. (The surf alt went through in the hold no problem ). So now I just bought a brush kit from Amazon for $30 with decent reviews, as my symptoms seem like replacement might fix the alt issue and keep the original. Does anyone have any experience with them? Am worried that even after getting the alt off replacing brushes O might have some surprises in store.

I'll be doing the Surf first and getting that running, as that's by far an easier alt to do, before tackling the hundy... Wish me luck!

In your case I’d make sure you have a spare alternator connector handy as the old ones like to explode when unplugged into a million little pieces.

Otherwise the job is VERY straight forward. Don’t forget to disconnect your battery and clip in the transmission hoses running under the radiator fan when you’re done. I’ve had one cut into the line leaving the car stranded.

 

[Marshmallow]

In your case I’d make sure you have a spare alternator connector handy as the old ones like to explode when unplugged into a million little pieces.

Otherwise the job is VERY straight forward. Don’t forget to disconnect your battery and clip in the transmission hoses running under the radiator fan when you’re done. I’ve had one cut into the line leaving the car stranded.

Just finished this job myself on our 2001 and would like to thank everyone for the write-up. My notes:

- just pull the rad hose already, I did it at the end when I couldn't tetris the old alternator out and should have started with pulling the hose.
- have a spare connector on hand, mine would not come out without the assistance of a pair of pliers, which shattered various parts of the plastic connector everywhere. I found a wiring pigtail at my local parts store (they did have to get it shipped across town from the warehouse)
- you can depin the existing plug and just use the plug from the replacement pigtail (no cutting/crimping/soldering wires). Use a pick to slide out the white locking clip next to the pins, then grab it gently with a pair of needle nose pliers and pull it completely out. Set it aside. Then use the pick to release each wire (I found an internet video to help me figure that part out). Push each wire into the new plug housing until it clicks, when all three have been transferred over reinsert the white locking clip. I mangled the last pin trying to get it out so had to play around with rebending the locking tabs to get it and the white locking clip back in.
- I didn't bother with undoing the plug, B wire or the bracket on the alternator until I had the alternator unbolted. I unbolted the bracket instead of unclipping the wiring clip but man it was tight (finally got a 12mm socket, long extension and used my cordless impact to bust it loose). When I reinstalled, I didn't install the bracket until the alternator was back in place - there is tons of room to do it once you can see what you are doing with the rad hose out of the way.