My 1971 521

[datzenmike]

 

'85 and up had the larger 62mm counter bearing. This one's looks like an early 56mm

[Crashtd420]

After reading all that, I would say wait for an L series 5 spd that will correctly bolt up..... 

Sorry Dp but all your questions makes things confusing.... 

It's not hard to swap the bellhousing housing but it's not the easiest thing either... 

 

If you buy a bellhousing make sure you get the front cover and shims that go with it.... then you know you have the right cover.... then you need the correct bearing... depending on what the transmission has....

Again all this isnt to hard but it's a little more than just slapping a different bellhousing on...

[d.p]

Agreed, will just wait for a complete 5 speed to show up.  

[d.p]

Found this one local to me which appears will work.  Per crash should be just what I need.  

 

https://washingtondc.craigslist.org/nva/pts/d/springfield-1979-datsun-280zx/7118783992.html

 

[datzenmike]

Those are good. Only made the one year for the first year 280-zx, '80 and on had the close ratio and too big 25% overdrive 5th.  This was a mid ratio and a 13% overdrive which is just right for 4 cylinder.

 

Found it in a stripped crushed car that sat for months till I noticed the valve cover and took a better look. (didn't even know it was a zx only that it was a six cylinder, later the steering wheel was what identified it. Still have the steering wheel now also in my 710)  Pulled it out and years later needed it for my 620. Had it in there for 10 years then sat for a couple and then went into my 710 for another 7 years. Lord knows how many miles were on it before I found it by accident.

[d.p]

7 minutes ago, datzenmike said:

Those are good. Only made the one year for the first year 280-zx, '80 and on had the close ratio and too big 25% overdrive 5th.  This was a mid ratio and a 13% overdrive which is just right for 4 cylinder.

 

I can get it for $200 bucks and its 30 minutes away from me.  

[datzenmike]

 

[d.p]

Ill take that as I should pick it up?  lol

[datzenmike]

[d.p]

lol this guy with the GIFs.    What should I check on this thing when I go look at it?  Can I shift into gears without a shifter?  

 

Edited May 6, 2020 by d.p

[datzenmike]

You could with a big screwdriver but keep in mind that the gears are upside down without the shifter.

 

 2...4...R

N--N--N

1...3...5

 

Put in first, mark the input and output splines, turn the input 20 times and if the output turns 6 times it's a mid ratio.

[wayno]

Personally I would go with cash and a big crescent wrench and half inch breaker bar, I would remove the filler plug first and stick my finger in and down into the fluid if it has any, if your finger comes out without metal color on it buy it(silver color is bad), black to golden/clear is fine.

If there is no fluid in it then I would take the drain plug out and stick my finger in and bend your finger and rub the inside of the case, anything but silver or metal chunks on the magnet.

I suppose you should shift it thru the gears also, keep in mind that if dry and having sat for years it may not shift into the gears with a light touch.

Edited May 6, 2020 by wayno

[d.p]

How big of a crescent wrench we talking? 

[DanielC]

This big?

[d.p]

Don’t got one that big. What’s that 12 or 14”?   I think have 10” Dewalt.   Ah Shit I see it now 18”.  Guess I’ll pick one up. 

Edited May 7, 2020 by d.p

[wayno]

You have a 521, what did you use to remove the plug in your 4 speed when you changed the transmission oil in it, you either need to remove the fill plug or drain plug to put your finger in it and see what the old oil looks like or if dry see what is left of the oil near the drain plug and see if there is any metal on the drain plug magnet.

I use a big crescent wrench, I suppose if you have a bunch of large wrenches you could take them and see which one fits, it's a very loose 11/16ths/17mm, but unless it is loose these fill plugs can be a bitch to get out, that is why I use a large crescent wrench, you will also need a 1/2" breaker bar for the drain plug. 

[d.p]

8 hours ago, wayno said:

You have a 521, what did you use to remove the plug in your 4 speed when you changed the transmission oil in it, you either need to remove the fill plug or drain plug to put your finger in it and see what the old oil looks like or if dry see what is left of the oil near the drain plug and see if there is any metal on the drain plug magnet.

I use a big crescent wrench, I suppose if you have a bunch of large wrenches you could take them and see which one fits, it's a very loose 11/16ths/17mm, but unless it is loose these fill plugs can be a bitch to get out, that is why I use a large crescent wrench, you will also need a 1/2" breaker bar for the drain plug. 

 

I never removed the plug because I have yet to change the trans fluid.  I did break loose the fill hole to check the fluid a couple years ago and it looked good.  I will just pick up a big crescent wrench on my way to look at it.  I got a 1/2" break bar already so I am good there.  

 

 

[d.p]

Got another question, it looks like the trans mounts for the 280ZX and my truck are completely different, does that matter? I had planned on using redeyes trans mount but want to make sure it will work.   

 

 

 

[d.p]

I picked up the trans.  What little liquid it had in it was black. No shavings or anything that I could see or feel. Both the fill and drain plugs were already loose so I’d do t have to break anything.   
 

Other than clean it up what should I do to it?  Figure out a way to shift gears? Replace some seals? 

[wayno]

You need to buy a shift lever for it, your 521 4spd shift lever is different and will not work on this transmission.

I know what I would do but I have had so many of these transmissions apart over the years that it's not a big deal, I would remove the cases and look everything over but the rear tail shaft case/housing is not one that newbies should be removing, it can be a pain to remove and a pain to put it back on, I expect if I had never had one apart I would fill it with gear oil, put it in every gear and spin the input shaft in every gear, if it felt smooth in every gear I would likely  call it good and install it, but that doesn't mean it would be good.

I had a transmission that had a leak after I put it in, it didn't seem like a bad leak, but I finally got around to pulling it out and opening it up to clean it and put it back together, well when I pulled it apart the center bearing cage had come apart, I have never had one that far apart before, so I installed another transmission instead and have been planning to rebuild that one, it has been setting a year now and I have not even ordered parts yet, so even though it may turn smoothly and make no noise it may still need rebuilt, if it has sat for years without gear oil in it there is always the chance it has some rust inside also, but if it has been inside all them years it likely is alright and has no rust, again turn the shaft in every gear, if it is hard to turn at all in any gear it should at least have the front case removed and figure out why it is hard to turn.

[datzenmike]

3 hours ago, d.p said:

I picked up the trans.  What little liquid it had in it was black. No shavings or anything that I could see or feel. Both the fill and drain plugs were already loose so I’d do t have to break anything.   
 

Other than clean it up what should I do to it?  Figure out a way to shift gears? Replace some seals? 

 

Pour a qt of ATF in it and roll it around on the lawn. Spin the input shaft in neutral. This will lube and rinse out anything loose. Dump it out and have a look at it.

[mainer311]

At a bare minimum, I would check it as best as possible, and replace the input and output shaft seals.

[d.p]

First thing I did was clean it.   Cleaned up pretty well and I considered taking the bell housing off and cleaning it that way but I never got around to it.  I am going to order front and rear seals, a gasket, shifter bushing kit, a reverse switch and will get some ATF.  For a shifter I would need a long one, but not sure what will work with this trans?  Will a 620 shifter work?  As far as putting it in neutral how do I do that without a shifter?  Oh and no rust that I could see inside, the metal inside the case still had fluid on it and looked OK from what I could tell.  Little rust on the input shaft but nothing crazy.  

 

 

 

 

Edited May 8, 2020 by d.p

[wayno]

Any 71B shifter will work, depends on what you want, there is this type.

 

With a long shaft the lever can get pretty close to the bench seat.

 

Here is the 1985/86 shift lever, it is different than the one above, I can't seem to find a photo of it not installed.

Edited May 8, 2020 by wayno

[d.p]

I guess I was just thinking of not wanting to have to reach down to shift.  Shifters seem fairly hard to come by.  Will ask Ted.