280zx 5 Speed Won't Reverse

[Dave WM]

heat. I have an induction heater just for this kind of thing.

[SteveJ]

To loosen the fill plug, I suggest heat with a 3/4 drive to 1/2 reducer (https://www.amazon.com/TEKTON-47823-4-Inch-2-Inch-Reducer/dp/B000NQ4R4G) and 1/2 drive 1/2 pipe plug socket (https://www.amazon.com/gp/product/B006L23ILO). That way you can use an impact gun or breaker bar safely on the fill plug. By the way, using the socket and reducer combo only works if the transmission is out of the car. There isn't enough clearance in the tunnel to do this with the transmission in the car.

[Muzez]

On 11/29/2020 at 5:12 PM, SteveJ said:

To loosen the fill plug, I suggest heat with a 3/4 drive to 1/2 reducer (https://www.amazon.com/TEKTON-47823-4-Inch-2-Inch-Reducer/dp/B000NQ4R4G) and 1/2 drive 1/2 pipe plug socket (https://www.amazon.com/gp/product/B006L23ILO). That way you can use an impact gun or breaker bar safely on the fill plug. By the way, using the socket and reducer combo only works if the transmission is out of the car. There isn't enough clearance in the tunnel to do this with the transmission in the car.

@SteveJ I cleaned up the plugs today and am letting the penetrant do its magic. The tooling is on order, but I was measuring the plug today. For the 3/4 drive to 1/2 reducer, it feels like there will be a little air gap between the plug and the socket. Is the goal to heat the plug itself? Or the fitting that the plug sits in? 

[SteveJ]

I'm not sure what you mean by air gap. After the penetrant has had time to work (and I hope you are using something strong like Kroil), apply heat on the fill plug. The 3/4 to 1/2 adapter should fit on the plug. Then you can use the 1/2 pipe plug to fit a 1/2 drive breaker bar or impact. 

When I tried it before, the 3/4 adapter seemed to fit the fill plug well. If yours was abused, your mileage may vary. 

[Muzez]

Quick Update: Still working to get the fill and drain plugs unstuck. Been dosing them with PB Blaster and heat for about a week, but no luck yet. Was thinking of maybe backfilling the warped parts of the drain plug with JB cold weld to form it back into more/less a square. Will keep you posted. 

In the meantime, I have been stripping away some of the red paint from the trans. Luckily, they didn’t do a great job of degreasing before they applied the paint, so it’s coming off pretty easily. Should have that gone today or tomorrow. 

One question for you guys: Some parts of the Trans case are smooth, but some areas have a texture to them that resembles slightly wrinkly produce. I am assuming the texture is part of the casting and is just more apparent from due to the dirt. Is this something you guys have seen before? And anything to worry about?

Most of the areas that have it look like this:

This was probably the worst of the sections

[SteveJ]

Try Kroil instead of PB Blaster.

[grannyknot]

15 minutes ago, Muzez said:

One question for you guys: Some parts of the Trans case are smooth, but some areas have a texture to them that resembles slightly wrinkly produce. I am assuming the texture is part of the casting and is just more apparent from due to the dirt. Is this something you guys have seen before? And anything to worry about?

Nothing to worry about, they all look like that.  If the trans is separated from the engine the best way is to haul it outside on a warm day and scrub down multiple times with a strong degreaser and a garden hose. I'm not sure JB Weld will stand up to that kind of pressure without cracking.  On sloppy fitting drain and fill plugs you can use pop can aluminum as shim stock,  cut 1/2" strips off of a pop or beer can and wrap it around square end of your breaker bar, 2-3 winds should do it then tap the 1/2" drive into the drain plug.

MAP gas in the yellow bottle burns hotter than Propane (blue bottle).

[Muzez]

1 hour ago, SteveJ said:

Try Kroil instead of PB Blaster.

Just ordered. Will be here in 2 days! What is so different about this stuff?

1 hour ago, grannyknot said:

Nothing to worry about, they all look like that.  If the trans is separated from the engine the best way is to haul it outside on a warm day and scrub down multiple times with a strong degreaser and a garden hose. I'm not sure JB Weld will stand up to that kind of pressure without cracking.  On sloppy fitting drain and fill plugs you can use pop can aluminum as shim stock,  cut 1/2" strips off of a pop or beer can and wrap it around square end of your breaker bar, 2-3 winds should do it then tap the 1/2" drive into the drain plug.

MAP gas in the yellow bottle burns hotter than Propane (blue bottle).

Good deal re: exterior texture. Unfortunately, it is officially winter here in Chicago and there won’t be a warm day for 3-4 months haha. I tried washing my weathertech liners after I brought the trans back and my pant leg froze.

Re Aluminum: I like this idea way better. Will give it a try! If all of this doesn’t work, it might be time to get professional help haha.

I have a can of MAP, but have been holding off on using it on the fill plug thus far because there is a sensor 2” away and was nervous about the extra heat melting it. 

[crayZlair]

24 minutes ago, Muzez said:

Just ordered. Will be here in 2 days! What is so different about this stuff?

I have a can of MAP, but have been holding off on using it on the fill plug thus far because there is a sensor 2” away and was nervous about the extra heat melting it. 
 

Kroil really works well !

As for the sensor, it is threaded in just like the plugs you can't get out. Catch 22 😀

Really, the sensor will come out, just apply the Kroil on the threads of it also.

[SteveJ]

I used PB Blaster on a plug for an O2 sensor bung. The plug wouldn't budge. I tried the Kroil, and I got the plug loose and removed with no thread damage.

I should also add that if you look up penetrating oil comparisons, Kroil is usually at the top. https://www.google.com/search?sxsrf=ALeKk03g9LCNLRF-NgNXl6cC20RsdNj0ew%3A1607365501682&ei=fXPOX5qVKcugtQX-gZXYCQ&q=penetrating+oil+comparison&oq=penetrating+oil+comparison&gs_lcp=CgZwc3ktYWIQAzICCAAyBAgAEB4yBggAEAUQHjoECAAQRzoGCAAQBxAeOggIABAHEAUQHjoICAAQCBANEB5Qu-0JWMvxCWCr9gloAHADeACAAXWIAbQDkgEDMS4zmAEAoAEBqgEHZ3dzLXdpesgBCMABAQ&sclient=psy-ab&ved=0ahUKEwjax4GOv7ztAhVLUK0KHf5ABZsQ4dUDCA0&uact=5

Edited December 7, 2020 by SteveJ

[Zed Head]

3 hours ago, crayZlair said:

As for the sensor, it is threaded in just like the plugs you can't get out. Catch 22 😀

 

Pretty sure the switch (not a sensor) is a straight thread, not a tapered pipe thread like the plugs, and it has proper flats for a wrench.  17 or 19 mm if I recall right.  Should come right out, your biggest worry will be damaging the wires which will be rock hard after 40 years of baking. 

Heat will have a big effect.  Those plugs have been bathed in transmission fluid on the other side for years and are steel in aluminum.  If they've never been out then they still have Nissan's super sealant on the threads.  Heat will loosen the sealant.  Heat.  Heat. Heat.  When I was removing my diff fill plug I could only get it to turn after heat.  As it cooled down it tightened up again.

[siteunseen]

I'm late on the cleaning, sorry, but those rubber caps from Lowes worked good for me during that. Foam oven cleaner from Walmart worked good too.

Oh yeah, a wire cup brush on a drill was helpful.

 

Edited December 7, 2020 by siteunseen