Alternator relocation?

[Apollo77]

77 620 pick up. I put a slightly larger alt in to accoutrements for the fact I'm nor in the 70s anymore, however it is more of a chore to get the damn thing in because of the lower coolant hose. And I max out a brand new and larger belt soon as it's in. Can I move it to the other side where the emissions pump is easily?

[kelowg]

Exactly which alt u using? I have a 60amp z alt and fits find. Just a matter of finding right belt. Mine uses 36 in belt,but they make belts in half sizes.

[datzenmike]

Yes the other side. In the mid '70 I had a 521 and the alternator mount sheared off the bolts in the block. A friend made something and welded it to where the air pump was. Worked perfectly.

[Apollo77]

Thanks mike, I knew it could be done I just didn't know if there were reasons not to. I'll look at what I have and need to move it.

Kelowg, I am using the one that was recommended for me just with 2x the output.

[datzenmike]

Exactly which alt u using? I have a 60amp z alt and fits find. Just a matter of finding right belt. Mine uses 36 in belt,but they make belts in half sizes.

 

It's not an easy fit, the idler arm is in the way underneath, and the rad hose, and the lower rad inlet casting on the timing cover. I fit a 60 amp car alternator to my 620 but used a 280z water inlet (it's bent more to the rear than the 4 cylinder ones) a 720  alt. block mount (it sits higher) and a shorter belt. This lifts the alternator up and away from the idler arm and moves the rad hose more out of the way. It still required that you put the belt on the pulley before bolting the alternator to the block mount. Eventually I had a 90 amp alt from a K car. All are a tight fit.

[datzenmike]

I have a welder now but when I did this 15 years ago I didn't. This would be the way to go and with some thinking would give you lots of room. Uhhhh watch out for the steering box.

[wayno]

Try using an 85/86 Nissan 720 alt. mount, it is a lower mount position so the alt. clears the upper radiator hose.

The way your doing it you have to tilt the alt. way to the side, when the engine shifts from torque, the alt. can hit the top of the idler arm and bust alt. mount bolts.

[datzenmike]

Maybe lower, I thought it was slightly higher than the 620 and this lifted the alternator away from the idler. But it was a long time ago.  Higher gave more room but now the lower rad hose where it enters the timing cover was closer and tighter. The Z car inlet is swept more to the rear and solved this.

[wayno]

As far as I know the top mount is an 85/86 alt. mount, see how the front alt. mount is lower than the top two mount holes.

The middle mount has the alt. mount above the two top mount holes, this one is early 720.

The bottom mount is from a 280Z car, it mounts the alt. lower also, but it also mounts the alt farther back, and the mount holes don't match the Z/L block mount holes.

 

When the alt. is mounted lower, it can be tilted more towards the engine, this allows one to use a shorter belt which moves it away from the idler arm.

It's all about that radiator hose clearance.

The big issue is the lower you mount the alt; the farther away from the block the lower alt. mount has to be, as the oil pump is in the way.

[Apollo77]

So would I be better off using a different mount or moving it? Right now I can't get a good alt to charge so I can't drive that much

[wayno]

So would I be better off using a different mount or moving it? Right now I can't get a good alt to charge so I can't drive that much

Sounds like your wiring is messed up.

Is the 1977 alt. internally or externally regulated?

[datzenmike]

'78 and up are internal but easy to swap the wrong one to an earlier truck. I believe if this is the case the truck won't shut off with the key.

[scooter]

I have a chevy alternator mounted on the other side of the block. Works good! Gets it away from the steering and the rad hoses.

[Apollo77]

Scooter do you have oics?

[scooter]

I got off my ass and went outside.

Its a bit longer than a stock mount cause all my pulleys are moved forward due to big ass ati super damper.

 

 

 

 

[Apollo77]

Doyou use one long bolt to get both lower mounting points?

[Apollo77]

Also is there anyone that can help me with wiring? I just don't want to keep messing with this and if it's user error they will catch on. 4 wires going to the alt, two should be in a plug but are not, one is a ground as far as I can tell, and one is to battery. I just want to make sure they are in the right spots. I can send pix via phone if needed

[scooter]

Yes i use one long bolt on the bottom too, and theres a plate on both ends. Before i trimmed the chevy alternator long bolt hole into a tab and ran a short bolt, sometimes it would break the bolt, last time it broke the alternator casting so this setup was devised.

 

That is an l16 water pump with an inch spacer in between the water pump and the pulley. To make this work on a stock motor youd have to build that bracket an inch shorter, and have to get creative with the tensioner.

 

For your alternator you should have a big battery wire, ground, one will be switched power from your ignition for the alternator fields and the last one is for the idiot light. If you have a voltmeter or a light probe you should be able to figure it out