New Truck - '71 521

[andyZ00m]

Ah nice, I didnt think about searching for kits with the hardware. Thats great. Thanks!

[Slow Loris]

I did this recently with the kit from seatbelt planet and it worked great. You need their hardware kit and also the seat belt mounting bracket which is the threaded plate and then the matching shoulder loop bolt (sold separately of course) that matches those threads. 
 

I tied a piece of floss onto the bracket, shoved it through the gap between headliner and top of B pillar, and lowered it to the holes I drilled. Use a long piece of floss you don’t want to drop it all the way down there. Use a tiny screw driver or sheet metal screws to hold the plate still while you bolt up the shoulder mount and you’re good to go.

 

Very satisfied with it. 

[Slow Loris]

Seat belt mounting bracket from seat belt planet

[andyZ00m]

16 minutes ago, Slow Loris said:

I did this recently with the kit from seatbelt planet and it worked great. You need their hardware kit and also the seat belt mounting bracket which is the threaded plate and then the matching shoulder loop bolt (sold separately of course) that matches those threads. 
 

I tied a piece of floss onto the bracket, shoved it through the gap between headliner and top of B pillar, and lowered it to the holes I drilled. Use a long piece of floss you don’t want to drop it all the way down there. Use a tiny screw driver or sheet metal screws to hold the plate still while you bolt up the shoulder mount and you’re good to go.

 

Very satisfied with it. 

 

Nice! Yeah the whole process makes sense to me. Im going to order the belts and see what sort of brackets and hardware is needed. Seatbelt planet says it comes with "all the needed hardware" but they dont say what that actually means.

 

Do you have photos of how you mounted to belt return behind the seat? Looks like theres plenty of room down there to do it in multiple ways.

[Slow Loris]

Yes I think like you say multiple ways. It wasn’t obvious when I started but this works:

 

 

Reason I did that is the threaded hole in the base of the B pillar is in a recess that the retractor thingy won’t sit flush in. Possibly you could use some spacers to work it out. Anyway, so I used the cab to frame mounting bolt.

 

 

In terms of the hardware, the “hardware kit #1” has nice big washers and that L bracket and I didn’t need the rest of it, I bought new bolts that fit the threaded hole in the B pillar and reused the ones into the floor, so there were some leftover bolts and washers from the supplied kit I never needed. 

[andyZ00m]

Awesome! Thank you!  
 

This is super helpful. I found a different hardware kit but it’s basically the same thing as you used here. 
 

I’ll update once I get some parts and start drilling holes! Haha 

[Montzzz]

On 11/9/2023 at 6:26 AM, mainer311 said:

The stock 30A alternator is terrible. The lights will dim with the windshield wipers running. Get a 50A alternator from a 510 with A/C. I kept the external VR on mine, and it's been fine.  I even run a powered subwoofer and crap, and it's way better.

Hi I saw your post and I will like to upgrade mine. Will this work ?

https://www.ebay.com/itm/273846188420?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=gXpry34STPO&sssrc=4429486&ssuid=jvceIx0FRBq&var=&widget_ver=artemis&media=COPY

[mainer311]

22 minutes ago, Montzzz said:

Hi I saw your post and I will like to upgrade mine. Will this work ?

https://www.ebay.com/itm/273846188420?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=gXpry34STPO&sssrc=4429486&ssuid=jvceIx0FRBq&var=&widget_ver=artemis&media=COPY

 

$150? Just get one on Rock Auto for half the price.

[andyZ00m]

34 minutes ago, Montzzz said:

Hi I saw your post and I will like to upgrade mine. Will this work ?

https://www.ebay.com/itm/273846188420?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=gXpry34STPO&sssrc=4429486&ssuid=jvceIx0FRBq&var=&widget_ver=artemis&media=COPY

 

Yeah that one doesnt look right and is very expensive. I think I got this one for about 60$ from a local guy here.

 

Also that one doesnt look like a Hitachi to me. This is the one I found.

 

[datzenmike]

If going to the 50 amp alternator from a car beware of the clearance between it and the idler arm below it when tensioning the fan belt.  It's larger diameter and also hugs the lower radiator hose more closely.

 

You might want to get a '78 and up alternator that has the voltage regulator built in. There is a small simple mod to the old external regulator when you remove it.

[andyZ00m]

11 minutes ago, datzenmike said:

If going to the 50 amp alternator from a car beware of the clearance between it and the idler arm below it when tensioning the fan belt.  It's larger diameter and also hugs the lower radiator hose more closely.

 

You might want to get a '78 and up alternator that has the voltage regulator built in. There is a small simple mod to the old external regulator when you remove it.

 

Indeed. @Montzzz if you need help with this I just went through it recently. Highly suggest getting familiar with the wiring diagram too if you havent already.

[andyZ00m]

Anyone have a recommendation for mirrors that actually fit the 521? The ones on mine now cannot be configured to actually give me visibility. The drivers side mirror is close but I have to lean over. 
 

I don’t really want the big truck mirrors although those would probably work. 
 

A buddy had some “Nissan” mirrors and I think they are for a z but they are worse in terms of being able to bend enough to actually let me see 

Edited January 13 by andyZ00m

[andyZ00m]

SPEAKING OF ALTERNATORS. Jesus fuck I cant catch a break. With all this weather, Ive been lamenting the little 35A chinese reman Ive had in my truck so went to install the "new good" one. Third alternator, this reman Hitachi from a 1980 240z is not producing current, well, it is but like 2VDC at the battery terminal and maybe 1-2VDC at the T plug.

 

Can someone please recommend to me a top notch alternator? At this point I dont care what it costs, I just want a 50-60A alternator that doesnt suck. I have a good regulator and I have a jumper plug for internally regulated alternators. Just need something reliable!

[datzenmike]

Have it professionally re-built. There are shops that specialize in this. You might get them to upgrade the output

 

What year 240z? '70-'71 were only 40 amp.

510s were 30/33 and 35 till '72 then 50 amp

Datsuns cars after say '73 were all 50amp and tucks after '80

 

All alternators from '78 on were internally regulated.

[andyZ00m]

27 minutes ago, datzenmike said:

Have it professionally re-built. There are shops that specialize in this. You might get them to upgrade the output

 

What year 240z? '70-'71 were only 40 amp.

510s were 30/33 and 35 till '72 then 50 amp

Datsuns cars after say '73 were all 50amp and tucks after '80

 

All alternators from '78 on were internally regulated.

 

Now Im not sure, my buddy said this was from 70-74 but he also said it was 60amp. Maybe its not 1980? None of this makes sense. I guess its possible hes wrong about it being internally regulated... but if that were the case it would be producing too much voltage not too little right?

 

Mike mentioned a guy about 45 mins from me that has an alternator shop. Gunna go to him and see whats up.

 

Edited February 12 by andyZ00m

[datzenmike]

A '72-78 would be 50 amp. So maybe it's a '72 or '73

 

 If you had a 30 amp and at night in the rain you pull to a stop light, the wipers slow, the heater fan slows and the headlight flick brighter/dimmer with the turn signal. This is because the output at idle is very low and with all the draw the voltage will fluctuate. The voltage is nominally 12 but when charging it just above 14 or tries to be.

[banzai510(hainz)]

thats a ext reg type alternator

 

Is seen once a internal volt regon a external and it was bouncing around the guy ran both regs while driving caoulnt figure it out.

 

just buy the stock size alternator. they smaller but fit better

7345 to 7360 is the belt sizes if you go larger

[datzenmike]

620 is very similar to the 521 in the engine bay. I fit a larger diameter 50 amp alternator into my 620 and it was tight. when the belt was tensioned it would swing down and bump against the idler arm and once the fan on it chewed a hole in the radiator hose. I used a 280z lower hose inlet on the timing cover and that moved the hose away and a later 720? three bolt alternator mount to the block which moved it maybe 1/4" higher away from the idler arm. You had to put the belt on first before bolting the alternator to the mount because a longer belt would swing it down onto the idler arm, but I got it to work. If these fit a 620 why did they use smaller ones???

 

Perhaps spacers on the engine mounts would lift the engine enough to clear. Maybe the 521 is different enough it isn't a problem.

[andyZ00m]

2 hours ago, banzai510(hainz) said:

thats a ext reg type alternator

 

Is seen once a internal volt regon a external and it was bouncing around the guy ran both regs while driving caoulnt figure it out.

 

just buy the stock size alternator. they smaller but fit better

7345 to 7360 is the belt sizes if you go larger

 

Youre saying the one I posted the picture of is an external regulator type?

 

I havent had issues fitting the larger size in this truck. It slips around the lower radiator hose no problem and mounts fine on the stock alternator bracket. Doesnt rub or interfere with anything.

 

I can plug in the regulator with this one and see if that helps but I donit think it would since even with nothing plugged into this thing, its not outputting more than 2 VDC at 3k RPM. Seems broke.

Edited February 12 by andyZ00m

[Stoffregen Motorsports]

X2 on the rebuild. I use a shop in Auburn called Boyle Future Tech. They can rebuild for about $100 with quality components and their turnaround time is very quick. They can also upgrade just about any alternator with higher amp windings, better or bigger bearings, your choice of pulley(s) and fans, etc.

[banzai510(hainz)]

45 minutes ago, andyZ00m said:

Youre saying the one I posted the picture of is an external regulator type?

Yes thats usually the external type alternator

 

 

I ran the bigger 50ampers on 521 before also but went back to the smaller.The Later 710 50amper did not have the black cage but they were still external volt reg type

Edited February 12 by banzai510(hainz)

[andyZ00m]

15 minutes ago, banzai510(hainz) said:

Yes thats usually the external type alternator

 

 

I ran the bigger 50ampers on 521 before also but went back to the smaller.The Later 710 50amper did not have the black cage but they were still external volt reg type

 

Jeeeeeesus. I was told this was internally regulated so I didnt even think to try it with the external regulator.

 

Just swapped it in and shes charging at 14.6V looking pretty.

 

I feel like an idiot for not trying that! Man I need to stop trusting that my friends know what they are talking about haha.

 

Thanks for the advice!

[banzai510(hainz)]

Glad its working

these really are simple trucks/cars.

But I only know Datsuns L motors

 

but dont listen to your friends anymore.Thats why Ratsun is here

Edited February 12 by banzai510(hainz)