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Crashtd420

A 521 in Massachusetts

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I just got thru having to fix my 5spd transmission, this is what happened to 5th gear.

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I have no idea how this happened but 3 teeth got ate up.

I had another 5th gear so I replaced it and all is good now.

I had to remove the tail housing to get to this gear as everything up front was good so the issue had to be in the rear, to get the rear housing off I had to remove the pin in the photo below to be able to move the shift lever to the side far enough to get it out of the gear selector slot, I also removed the speedo drive and the 5th/rev lockout. 

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I guess I made a mistake though when I put it back together, even though I cleaned the mating surfaces up it is leaking/oozing out the bottom center between the center piece and the front housing, but the transmission is in the truck now so I am trying to stop it temporarily for right now without success so far, this has never happened to me before in all the years I have been dealing with these transmissions, now I wish I had sealed it as to fix it right it has to come back out but I am not ready to do that right now.

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Removal is always easy, just lift up and twist back and forth to detach from the shift rods. Assembly is not near as easy. Set to neutral. Hold the shifter hard toward the 5th/reverse gate while staying in the neutral gate and lower together aiming for about 10 or 11 o'clock and as it nears turn to 12 o'clock aligning the dowels. This should slide the striking lever into the neutral gate, it doesn't, or rarely, so make sure you have all the gears. Just because it went together doesn't mean it's not locked in 5th.  If the shifter goes in all gears and the input turns just pull the rear case apart 3/16" and work some sealer into the crack. Don't be a chev owner and over do it. Anything that squeezes out, an equal amount goes into the transmission. 1/8" is lots. 

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1 hour ago, Stoffregen Motorsports said:

Removing the tailhousing is not a big deal. You will have to wiggle it around a bit to get it loose, but once you do, you can now see how it goes back together. It's always easiest to assemble everything while the trans is not in a gear, then the shift rail fingers all line up, making it easy to install the tailhousing.

 

This is not a corner I would cut.

 

Stop making sense..... damn.... now I'm gonna be cursed if I dont do it.....

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Damn it Mike I am a Chevy owner.. I'm screwed...... 

Thanks for the extra info wayno and datzenmike.... 

 

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I'm a Chevy owner. Right now I've got at least three Chevy trucks. That doesn't make me a hack either.

 

Maybe it's because I was a Datsun owner first then ended up with domestic vehicles later...?

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Just trying to be funny...

 

I love my Chevy... I'm still driving a 99 Silverado with 275000+ miles on it.....  things gonna rot before that motor gives up..... Im trying not to put any more money into it but it just keeps going, plus its 4x4.... having the datsun running, and getting my wife a newer Subaru has allowed me to keep alot of mileage off the chevy this year..... 

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Maybe different on new engines that either haven't been apart yet or are closer tolerance? Old chevs around here in wrecking yards have 1/4" blobs of that red or blue RTV on intakes, oil pans (are the worst) and thermostats. See it on exhaust manifolds, carb bases, valve covers even on a rad hose!!! WTF GM owners? this is what gaskets are for.

 

I09FWrH.jpg

 

Pulled this out of a KA head water jacket. Chevy blue.

 

SX owner must have been a chev owner too.

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If you use Right Stuff gasket maker on the oil pan, lay a nice bead on the pan and let the bead skin over before putting it on. That’s how I use it on diff covers so that it doesn’t ooze into the cavity.

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3 hours ago, Crashtd420 said:

Just trying to be funny...

 

I love my Chevy... I'm still driving a 99 Silverado with 275000+ miles on it.....  things gonna rot before that motor gives up..... Im trying not to put any more money into it but it just keeps going, plus its 4x4.... having the datsun running, and getting my wife a newer Subaru has allowed me to keep alot of mileage off the chevy this year..... 

I too have a 99 Silverado with high miles. 410000km which is slightly lower than yours. Best truck i ever owned i think. Bought it as a farm beater, but it drives so nice its now my daily. Uses NO oil, and runs like a top. Body is failing, but I'll drive til its dead. Could be a long wait...

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13 minutes ago, mainer311 said:

If you use Right Stuff gasket maker on the oil pan, lay a nice bead on the pan and let the bead skin over before putting it on. That’s how I use it on diff covers so that it doesn’t ooze into the cavity.

 

2okevr.jpg

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Well I got the parts in that I need....

 

20181210-165341.jpg

 

I wish I could get more done but life is hindering that.... 

I have time tomorrow so I'm hoping to get the tail housing off ... and probably give both the cases a good cleaning to get ready to reassemble...... 

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So I've already removed the speedo drive..... and I believe this pin needs to be removed.....

20181210-171152.jpg

 

What's the bolt next to it?

 

Next I believe is the shifter assembly/rod....

 

20181210-171211.jpg

 

I'm assuming that slides out after removing the pin.....

 

Is there anything else that needs to be done to remove the tail housing?

 

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Also I'm curious about the reverse switch..... is this it on the short 71b?

20181210-171201.jpg

 

The L series case has a sensor too....

20181210-171226.jpg

The front case from the 5spd did not...

 

I noticed this notch on the reverse/5th rod .... which looking like it's for the reverse switch..... does that line up and work? 

 

20181210-171242.jpg

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20 hours ago, Crashtd420 said:

So I've already removed the speedo drive..... and I believe this pin needs to be removed.....

20181210-171152.jpg

 

What's the bolt next to it?

 

Next I believe is the shifter assembly/rod....

 

20181210-171211.jpg

 

I'm assuming that slides out after removing the pin.....

 

Is there anything else that needs to be done to remove the tail housing?

 

Yes, the pin gets removed, but the shifter assembly stays inside the tailhousing. Removing the pin makes it possible to rock it back and forth enough to get the fork lined up. Same goes for that "bolt". There's actually a detent spring and ball inside there so remove with caution, and maybe a small magnet to catch the ball.

 

That should be all that needs doing to get the tailhousing off.

 

Again, before you apply RTV for reassembly, try a couple of dry runs installing the tailhousing. This way you'll learn the tricks before you make a mess of the RTV. Obviously, you need to install both halves of the case upon final assembly.

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Thanks, Hopefully it's that simple for me... 

Sounds like a good idea to test fit the tail housing.... 

Of course I had the day to myself till my son decided he was gonna be sick and unable to go to school.....

Datsun will have to wait.....

 

When I do finally get to assemble the transmission does it matter which end i install first?

I was thinking about doing the front case first so I can stand it on the bellhousing and just drop things in....

 

Is there any reason that's a bad idea ?

 

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20181210-171152.jpg

 

This does not need removed as it's against the striker rod which stays inside the rear case. The speedometer pinion will likely engage the worm alright but why not have it out just to be safe.

 

20181210-171201.jpg

 

This is not the reverse switch but the top gear switch and it too engages the striking rod and stays with the tail case and does not need to be removed.

 

The only thing to be removed from the rear case is the speedometer pinion, and even that is not totally necessary but won't hurt.

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Thanks... the speedometer pinion has already been out for a little bit... I'm actually using it in my 4spd.... 

 

All sounds easy just need to get to it...

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All that's sliding back up into the rear case is the mainshaft. The only thing engaged with the mainshaft is the speedo pinion.

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For final assembly, I put two 2x4s on the ground (one to support the bellhousing on either side of the input shaft), then stand the bellhousing on end. Apply RTV and lower the trans into the bellhousing/front case. Tailshaft comes last.

 

You need the 2x4s or the input shaft will hit the floor.

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Sounds like a plan.....

Unfortunately I just got home from having the second of 2 hernia surgery's, 1st was 3 weeks ago.....

So it will be a couple weeks before I can even try to put it back together now...

I'm so bored,  I can wander around but really cant do any work for a couple weeks..... 

Maybe I can sucker someone to come over and help.... 

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Oh fuck I hear you. I hurt my back once and had to crawl around doing small things on my 620. Doing nothing was worse. Keep your mind off it. If it hurts stop doing what you're doing and try something else.

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36 minutes ago, Stoffregen Motorsports said:

Hang in there buddy. It only gets worse from here... Family life has a way of putting the brakes on fun projects.

I'm pretty lucky, they allow me to do what I need to do.... im glad I started the project when I did, it would be a little more difficult if I was starting it now... Having the datsun driveable definately gets me a little more credit, I believe my wife is still shocked it's on the road again.. it was the go to vehicle all summer any time we could

its winter now and I'm really not supposed to be doing things with my recent surgery so I dont mind being forced to relax ..... I never real get the chance..... 

I believe I can finish the transmission swap in an afternoon with my friends help, minus the fact I'll have to mod the bracket....

Most of the other things on my list of things to do would only take an hour or so to accomplish, other things will be real quick like a new fuel filter.....

I do miss driving it.... but I'm gonna luv it even more with that 5spd in there..... I do about 50% highway driving so its gonna help alot....

Just realized I'm rambling I think the meds are kicking in.....

 

 

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14 minutes ago, Stoffregen Motorsports said:

Meds kicking in...reminds me of that scene in Madagascar -

 

Not quite that good..... 

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