how to repair you 620 window regulators the quick and easy way.

[91hrdbdy]

So I couldn’t find any 620s in the yards with good regulators and I was browsing ebay and saw that a 720 regulator was very similar so I took a gamble and spend the 50 bucks in hopes I would be able to make it work.. I did.. here is how

 

Items you will need

A small cut off wheel .

A small 110v welder.

2 datsun 720 regulators

About 1 hr per door.

 

First off a caution note the steel you will be working with is zinc plated ensure proper ventlation and wear a resperator when welding as galvinized steel is poisionious when it is welded!

 

Here is a shot of both regulators.  As you can see there similar but not close enough to bolt right in.

 

Step  1 

 

making the simple jig to hold it all in place.  All I did was screw down the 620 regulator to my wooden bench. And I then ran a small drill bit through the mounting hole in to the wood and left it in place at a locator

 

 

 

 

 

 

Step 2

 

was to measure 2.50” from the end of the 720 regulator and place a mark do the same thing but measure from the start of the riveted top piece and it should place a line at the bottom of the riveted top piece like so.

 

 

 

 

 

Step 3

 

Cut the 720 regulator on the outside of the line and do the same with the 620 regulator but cut both lines. You should have something like so. (Turn you regulator crank until the clears the gear before you cut)

 

 

 

 

 

Step 4

 

You want  to make sure it aligns back up. So you will need to place the sectioned crank assembly in the gear and  make sure it sits nicely in the gear mesh and you have a nice clean line to weld up. Do the necessary sanding to ensure a good fit.  A good indication of proper gear mesh is that the part will line back up with the old scrub marks from the previous regulator.  Like so

 

 

As you can see here I trimmed a little too much here but ill weld the gap using a copper plate to back it.

 

 

 A good indication of proper gear mesh is that the part will line back up with the old scrub marks from the previous regulator.  Like so

 

 

 

Step 5

 

No then time to place the tack weld.  I set my miller 140 on 16ga and I preferred to use a wire speed of about 50.  Place a tack weld at both ends while the sprocket is meshed up with the regulator crank assembly let it cool and cycle it through the entire track to make sure it is aligned properly.

 

 

 

 

Now turn the crank till the dismounts the sprocket and fully weld the parts together. Letting them cool between tack the goal here is to keep the temps down to prevent warping.  After its done re-cycle the regulator and make sure it works like it should if you got your metal too hot here you make have to tweak it to make is work smooth.

 

 

 

 

Now remount you regulator to the jig board with the screw and place the upper piece in the jig if you cut right it will line right up. Like so.

 

 

Weld it up just like you did in the previous step slowly letting it all cool between tack. 

 

And Finally re install the regulator in the door. No depending on how accurate your cuts were and how much the part move when you jigged it up you may have to oblong the front hole a little.

 

 

 

That’s it.  Hope this may help some of the 620 owners out there.

[]2eDeYe]

Great idea and write up. Nicely done! :thumbup:

[jastrunk97]

Shouldnt this be moved to How-to?

[Eagle_Adam]

ratsun engineering at its finest!

[GRpufnstuf]

Is this fixing the window flopping inside the door?

Or is there another different problem I should be watching out for?

[yenpit]

GR, buy the felt window "run channel" right from Nissan, in a roll, I think it's enough to do a pair of doors.  I did my 510 last year......it's alot of piece-by-piece work, cuz you have to at least take the door glass out of the vertical channels and move it out of the way, OR better yet just take it out, but it's straight forward work.  After installing, the car sounded like a Mercedes Benz when I slammed the doors!

[650savag]

You could probably just make one cut and one weld if you wanted to use the two  mounting holes in the 720 piece that you cut out.  You would just need to measure and drill 2 holes in the door panel for the 2 new mounting holes.  They will be covered up with the door panel.

[odmanjohnson]

Hmmm...

[91hrdbdy]

the 720 regulator is way different but maybe you can figure out a way to do it.