My 1977 Datsun 620!

[Longbeachjesse]

Hello everyone! I just picked up a 77 620 because I missed having an old car. I got it for $2500. I previously owned a 1973 BMW 2002. Today I will be swapping a 1985 Nissan pickup alternator into it. Im going to run the stock engine until it dies then do a engine swap just haven't decided which motor to go with. 

 

https://ibb.co/C8K95Gs

https://ibb.co/9b59m9F

[datzenmike]

 

Really nice truck

 

 

 

Before you do the alternator swap there are some things you need to know.

 

Your '77 uses an external voltage regulator, the '85 is an internally regulated alternator. There is more to this that disconnecting the regulator. There are a couple of wires to cut and join but more on that later...

 

The '85 is physically a larger diameter than the tiny 35amp unit in the 620 and will most likely hit the top of the 620 idler arm when the belt is tensioned. Shorter belt? Well then the lower rad hose return above the alternator is in the way. If you can get this alternator mounted and not chew a hole on the rad hose I'll show you how to convert/disconnect the external regulator and fix the automatic choke relay that would stay on with the key off.

 

I've done this swap with a 720 50 amp alternator and was NOT happy with it. I used a different alternator mount to the block and replaced the lower rad return casting with one from a 280z/zx that positions the rad hose more to the rear and out of the way. To get the shorter belt on, I had to put it on the pulley first then bolt the alternator to the engine mount. The  alternator is closer to the block so there is less belt in the pulley groove and it slips and there is less room for tensioning. 

 

 

[Longbeachjesse]

2 minutes ago, datzenmike said:

 

Really nice truck

 

 

 

Before you do the alternator swap there are some things you need to know.

 

Your '77 uses an external voltage regulator, the '85 is an internally regulated alternator. There is more to this that disconnecting the regulator. There are a couple of wires to cut and join but more on that later...

 

The '85 is physically a larger diameter than the tiny 35amp unit in the 620 and will most likely hit the top of the 620 idler arm when the belt is tensioned. Shorter belt? Well then the lower rad hose return above the alternator is in the way. If you can get this alternator mounted and not chew a hole on the rad hose I'll show you how to convert/disconnect the external regulator and fix the automatic choke relay that would stay on with the key off.

 

I've done this swap with a 720 50 amp alternator and was NOT happy with it. I used a different alternator mount to the block and replaced the lower rad return casting with one from a 280z/zx that positions the rad hose more to the rear and out of the way. To get the shorter belt on, I had to put it on the pulley first then bolt the alternator to the engine mount. The  alternator is closer to the block so there is less belt in the pulley groove and it slips and there is less room for tensioning. 

 

 

Thanks for your reply ! I live down the street from Left Coast Datsuns and picked this piece up from them for the wires. He also walked me thru what needs to be done to swap it and I took pics of it all. Hopefully its as easy as it says. Ill let you know how its goes !

 

https://ibb.co/cF6pRnY

 

sorry for the links btw I haven't figured out how to post the pics in the body of the post.

[banzai510(hainz)]

if you keep oil in it and keep it from overheating it wont die

 

since its a 77 learn how to adjust points and ck th distributor often for wear

that's where young novice Datsun owners kill their vehicles.  Get a electronic distributor  this will then be 50% more relaiable if you don't know points ignition

 

but you were driving a 73 2002 so maybe your a expert already

Edited April 27, 2020 by banzai510(hainz)

[FrankRizzo]

On 4/25/2020 at 12:46 PM, Longbeachjesse said:

Thanks for your reply ! I live down the street from Left Coast Datsuns and picked this piece up from them for the wires. He also walked me thru what needs to be done to swap it and I took pics of it all. Hopefully its as easy as it says. Ill let you know how its goes !

 

https://ibb.co/cF6pRnY

 

sorry for the links btw I haven't figured out how to post the pics in the body of the post.

 

That is my green 620 in Chucks shop...next time you go back ask him when it will be done...☺️

 

.

[Jersey]

12 hours ago, banzai510(hainz) said:

if you keep oil in it and keep it from overheating it wont die

 

since its a 77 learn how to adjust points and ck th distributor often for wear

that's where young novice Datsun owners kill their vehicles.  Get a electronic distributor  this will then be 50% more relaiable if you don't know points ignition

 

but you were driving a 73 2002 so maybe your a expert already

CA truck, it shouldn’t have points. It most likely all ready has factory electronic ignition.