Super hard to get 280z 5 speed into gear

[luseboy]

Well I haven't really done a thing to my car in about a year and a half, and just this past weekend finally got motivated to start working on it again, which is cool because it's close to being a drive-able car.  Anyways a couple years back I bought a 280z 5 speed trans, which I quickly tore apart to clean up and make sure it wasn't junk.  I then installed an msa short shift kit (which I cut down super short) and put it on the car.  Well I actually had to take it off because I put the rear case on wrong and it was inbetween gears.  Anyways it's been sitting for a couple years now and the shifter is extremely hard to move into gear.  If someone spins the rear axle I can get it to hit the gears with a lot of force but otherwise I can't at all.  I'm curious as to what could be causing the trans to not want to go into gear at all.  My first thought is that I need to pull the shifter out and make it longer again, as I'm thinking maybe it's just so short that I don't have enough leverage, but when someone is spinning the rear axle it isn't too terribly hard to shift. My other thought is that maybe the fluid has settled down to the bottom of the bellhousing and the thing just needs to be driven some before the trans will start shifting well.  But then of course the bad thoughts of "I fucked something up bad!" start coming in.  Now I know it is at least able to engage reverse because with the engine running I can get it to grind trying to go into reverse (clutch hydraulics are not set up properly either but that's a whole different thing).  I know no one can give me a definitive answer but I'm just looking for some experienced opinions as to what would be causing this.  I'm probably gonna take the shifter off this coming weekend and lengthen it back to a reasonable height, so hopefully that will make a difference, but could there be something else going on here? I should also probably mention that when I did get it into gear and had someone spin the rear axle, there was an awful grinding noise that sounded like it was coming from the rear case.  I'm thinking(hoping) maybe the trans will work a whole lot better once I start driving the car and get the trans fluid up to temp and what not, but maybe that's just because I don't want to take the damn thing apart for a third time haha. 

I know I probably didn't provide nearly enough info but hey that's how these things always start off.

Thanks!

Edited March 29, 2016 by luseboy

[Pillar]

Shortening the shifter will definitely require you to use more force to get it into gear, but unless you shortened it to like 5 inches long, you should still be able to shift it relatively easily.  The early 280Z 5-speeds had a somewhat common issue of having the 5th gear go bad due to that fact that it shares a fork with the reverse gear (this is a reason, in addition to the closer ratio, why the later model 280ZX trans is more desired).  I have never experienced this issue myself so I really dont know the specific symptoms that others have may experienced when running into this issue (and it may vary) but I would think this could be a likely possibility.  

 

Now as you stated, if the trans has been standing up for a long time, the gears at the back will be very dry.  You said that you had previously torn it down to look things over.  Did you shift through the gears after reassembly?  If so, did you notice any issues then?  If not, it could just be that years of sitting with the gears out of the oil and drying out is what is causing the noise (however unlikely).

 

Another thing to consider is where it was stored.  I have seen transmissions (even ones stored in garages) that have sat for a long time gather rust on the inside.  Moisture has a nasty way of finding its way into everything eventually, and if the gears were not covered in oil, eventually they could develop a touch of rust (even inside the case) if a small bit of moisture gets in.  Now usually the amount of rust I am talking about is extremely minuscule (most of the time just a few tiny spots of surface rust on the gears) but even a tiny bit of rust can cause things do be difficult to move if it is in just the right spot.

 

Whatever is the issue, I hope you are able to figure it out.  Good luck!

 

Pillar

Edited March 29, 2016 by Pillar

[seattlejester]

The simpleton in me would ask if you made sure to fill it with the proper amount and kind of oil after you took it apart.

 

If the wheels have to be turning, I'm wondering about the clutch. Do you have enough travel? Have you bled it recently? Just get in the car with your feat up and your head in the foot well and pump the clutch with your hand and a flash light, have your dad look at the slave and see if it has good throw as you pump it. If it doesn't have proper engagement it could be hard to get it into gear.

 

You could think you are getting the gear, but if the clutch is not disengaging all the way out you could be partially engaged all the time which would cause lots of grinding. 

 

It is overall a pretty basic test for the clutch, do as mentioned above and visually check that the clutch pivot isn't binding. Then make sure that the clutch slave is moving out enough and then just as importantly going back to rest. 

 

I had a short (in height) shifter and it was pretty easy to shift. My short shifter kit for my toyota drivetrain required quite a bit of breaking in and adjustment to be able to shift it with one hand.

[NewZed]

 But then of course the bad thoughts of "I fucked something up bad!" start coming in.

 

 I should also probably mention that when I did get it into gear and had someone spin the rear axle, there was an awful grinding noise that sounded like it was coming from the rear case.  I'm thinking(hoping) 

Either you messed something up or it was messed up when you got it.  Hope's probably not going to help you.  Stiff shifting might get better, but awful grinding rarely goes away.

[Pillar]

You mentioned that the clutch hydraulics were not set up properly.  I would address this issue first before thinking that the trans is messed up.  If the clutch is not fully disengaging when you push in the pedal, then the input shaft on the trans will still be spinning along with the motor (just slipping a lot).  This could indeed cause a lot of grinding and difficulty while trying to shift into gears.  The fact that you are only having trouble with 5th gear doesnt negate the clutch as a likely issue.  I suggest getting the clutch sorted and see if that clears up any issues.  If it doesnt, well then you can at least eliminate it as a potential cause for your problems, and as you stated it needs to be adjusted anyways, so no loss.

[NewZed]

Remove the drive (propeller) shaft and turn the output shaft by hand and you'll take out all of the other possible grinding possibilities.  It's a pretty simple problem.  Don't forget to drain the fluid first to avoid a mess.  Look for chunks and fine shiny stuff while it's out.

[luseboy]

I guess I should have made it more clear that I'm saying it isn't going into gear with the engine off and the car sitting. The first time I put the trans in it wouldn't go into gear at all, so I took it back out, removed the rear case, and found that I had accidentally put it back together when it was inbetween gears. So I fixed that and put it back together and then it shifted fine (though required a whole lot of effort then too). Now the only way I could get it to shift gears was with someone spinning the rear end, which it would hit all gears of then, but made a grinding noise in 3rd and 5th I think. Unless I'm missing something, the clutch shouldn't have any effect on the trans shifting with the engine off, right? I'm thinking the small amount of rust that Pillar had mentioned is a likely culprit, but I also think that the shifter is too short as it's only sticking up above the console like an inch or two. As far as fifth gear going out, from what I could find online that is usually indicated by the shifter popping out of fifth while driving, so shouldn't effect what I'm having troubles with. I bought the trans for like $80 so if it is junk I'll either pull it apart (again) and actually rebuild it or just replace it with a better one and hold on to this one for spare parts (maybe use the bellhousing for a 240sx trans swap in the future). I just wanna be able to get it to work for awhile so I can drive the car (have never driven a Z but have had mine for 4 years lol). As far as the fluid goes I put that in years ago and can't remember exactly which one I put in but I know I did my research and it was redline gl4 mt90 I believe, it was what was reccomended to me on this site and is a soft metal safe version. I'm more concerned with the shifting itself rather than the grinding as if a bearing went south in there (they all seemed fine a couple years ago when I had the cases off), I'll just keep a look out for a different trans. I know I had talked to someone on here at one point that said their transmission wouldn't shift when it was sitting for awhile until they had someone spin their rear wheels for them, but I can't remember who it was or the context.

[NewZed]

You might have a memory from when you had it part of what is involved in "going in to gear".  Not much.  A coupling sleeve with internal teeth moves over a synchro ring and the external dog teeth on the gear being engaged.  Three little pieces of metal (inserts) compress three little springs along the way.  So rust may be a factor since the coupling sleeve and the gear will rust.  If the synchro cone on the gear rusts that will hinder the synchro ring aligning the teeth.  Could be a factor.  The shifting rods can rust also.  Aluminum can build up an oxide layer also, so the holes might be gummed up.  So, if ti worked "okay" years ago, it will probably come back to at least that level.

 

I had an old transmission that sat for years, that worked itself in to better shape after a few miles of driving and picking the right fluid.  My best guess was rust on the parts that need to be smooth to work right.  Your best path forward might be to just drive it.  Start it in 1st gear if it won't engage with the engine running.  Match RPM while you're trying to wear it in.  For $80, not much to lose.

 

Here's a video of a guy shifting his FS5R30A transmission, with both cases removed.  Lots of other good pictures also.

 

http://beergarage.com/PathTransmission9Shift.aspx

Edited March 29, 2016 by NewZed

[luseboy]

NewZed this is totally what I'm thinking, I think once I start driving it a lot of things will come together, or at least I will get a better idea of what's going on with a lot of things. I've talked to a few people who have had transmission troubles after the car had sat for awhile, which went away with use. I reently got rid of a hardbody truck that had a blown up transmission I drove on for a year that worked fine once I put some redline in there. So I'm sure it will get better, or at least allow me to drive the car for a little while. Maybe I can find a cheap 4 speed or something and start gearing up for a 240sx trans swap. I guess at this point I'll focus on getting the clutch working so I can at least try to drive it. I think I need to make a new slave cylinder push rod to make that work, as it definitely isn't moving enough. I gotta start with pedal travel first then go from there, but I think my custom adjustable slave rod is the main problem there. How stiff are these clutch pedals supposed to be?

[seattlejester]

Ah that clears up some things. With my nissan 5-speed I had a similar thought when it wouldn't go into certain gears smoothly. It depends on where you stop. With the clutch working it should engage all gears without problem, but without the clutch it might only engage a couple while stationary. I panicked when it happened to me and thought my trans was also bad, a friend explained the reasoning behind it and confirmed it with his own car, I don't have my phone so I can't look it up, but it happens. It happens on my toyota 5-speed too, I can't row through the gears making vroom vroom noises without it fighting me on some gears.

 

Make sure the hydraulics for the clutch are working, check fluid level, and slowly go for a little drive around the block. I think you will find it will shift into the gears once in motion with the clutch.

 

Why do you have an adjustable slave rod? Are you running a strange clutch combo?

 

Clutch pedal resistance is going to have to do with the return spring and the pressure plate, a lightly sprung plate will be easy to engage and disengage, a heavily sprung one will fight you quite a bit.

[Pillar]

NewZed has the right idea. For only having $80 in it, you are not risking much. If it is indeed rust, driving it around the block a few times should knock it all off and clean up all the surfaces. I would start out at low speeds and run through all the gears, then gradually work your way up a bit. If it gets better (which may be a very gradual thing) then keep at it. Once the transmission warms up, things should work even better (assuming you have good fluid in it). It goes without saying (even though I am obviously saying it anyways) that if the noise or grinding gets worse, you probably should return to base and reevaluate.

 

Have you opened your drain plug and looked at the fluid at all? I know you said it has been sitting for a few years. Oil (especially when used or stored in something like a transmission for a long time) can break down over time. This is why you are supposed to change engine oil after a certain time period (ex: every 6 months) regardless of how many miles you put on it in that time. There are a lot of other substances/build-ups/chemicals/etc in engines and transmissions that can change the effectiveness of the oil. This is also true if there is any moisture that has infiltrated into the case, as real as any rust resulting from said moisture. It may be worth replacing the trans fluid for something new (even if it is something off the shelf at your local parts store). I would especially recommend changing fluid if a few laps around the block causes things to start working better. If it is indeed because of rust or corrosion, then all that stuff that has now been cleaned off your gears/forks/etc, is now dirtying up your fluid.

 

Again, hope you can figure it out.

 

Pillar

Edited March 30, 2016 by Pillar

[luseboy]

SeattleJester, I think it was actually you who I was remembering.  I know I had a post about the same thing basically a couple years back.  I guess I will get get it into first gear and start it in gear and take it for a quick little drive.  The problem is that I live halfway up a big steep hill, so I'm trying to figure out how I can test it on flat ground.  Luckily my driveway is long enough to get a quick little test but I wouldn't be able to get it out of first gear.  I just bled the clutch for the second time last weekend.  The first time I put it all together I failed to install a copper washer at the slave cylinder and instead used pipe thread compound.  Well low and behold it leaked all it's fluid out.  Now I got it bled again after putting a copper washer on (and spraying myself in the eyes with DOT like an idiot lol).  Although now that I think about it I didn't re bench bleed the master cylinder so maybe that's part of the current problem.  Anyways even now that it's all bled out, the slave isn't moving the fork enough.  I need to verify that I have the right amount of pedal travel first, then I'll look at the slave cylinder rod.  I had made a custom adjustable rod just so I could make sure everything was set up right, as I got the slave with a non-adjustable one.  Maybe that's not necessary? My thought is that maybe the rod is too short and that's why the fork isn't being moved enough.  The pedal has no resistance until about an inch off the floor, and that's when the fork starts moving, but it's not enough.  I guess I should also bench bleed the master again.  Clutch is just a 240mm set up from ebay, some re-branded set up that might not last long.  

 

Pillar, that's some good advice.  I haven't looked at the fluid yet, but will do that. I guess I'll just plan on replacing the transmission fluid and engine oil after I drive it a little bit, as the oil is definitely over 6 months old (maybe that's why my oil pressure is going over 100psi when I rev the motor, but I'm gonna check the relief valve in the oil pump first). I should be fine to get things up to temp for the first few times with the existing fluids though right?  There's probably a lot of crap in the motor from taking it apart and there might be some in the trans too, so it's probably a good idea to replace it anyways.  At any rate once I start driving it a bit I will have a much better idea of what's going on.  I still got a good deal on the trans, even if it ends up being a spare.  

[Pillar]

I could be wrong, but 100psi seems rather high to me.  The factory gauge (at least on my 76 280Z) only reads up to 90psi, and I have never gotten it up there.  I assume by this, that your motor oil has not been changed in a long time either?  Has it been sitting for years like the trans as well?  

 

If that is the case, I would replace the oil before driving it anywhere (especially in the motor as you are much more likely to cause damage in the motor due to oil oil than you are the trans).  The old trans fluid may be fine for a few laps around the block, but it all depends on how bad it is.  If it isnt that dirty or sludgy, then it will likely not hurt anything to drive it a short distance at low speeds.  But if it looks like molasses or has absorbed a large amount of water, metal filings, or rust, then it could potentially cause some lasting and/or severe damage.  

 

Again, it might be fine to run around the block a few times with what is in there, but some bottom shelf/cheap oil that is brand new will be better than even the priciest oil that has sat for years and is full of impurities, and could save you from doing much more costly and long term damage.  

[luseboy]

Ya lol it is quite high.  I'm pretty sure the problem is the relief valve in the pump, apparently they tend to get stuck and then you just build pressure like crazy.  Either that or some of the oil galleys are clogged up.  The motor oil has been in for like 2 years, but is good synthetic oil.  It still looks like new and smells like it too (I didn't taste it so not sure on that part).  I'm actually thinking I should ditch the synthetic for some good ol' dino oil, which would be a good idea.  Maybe the old oil is the cause for the high pressures, guess I will go get some dino oil before I run it again.  

 

I'll take a look at the trans fluid this weekend as well, I'll just pull off the filler cap and get a small sample out to take a look at.  I don't want to dump that fluid if I don't have to, it was expensive stuff! The same stuff kept my hardbody trans working great for a year even though I pulled 1" long chunks of bearing out when I drained the fluid.  I don't think there would be much water in there, it has been indoors the entire time I've had it, in a nice garage that has good door seals and what not.  But then again it's not out of the question.  If I remember correctly I need a gl4 for this trans right?  Gl5 will damage the soft syncros, right?  I've had to source Gl4 three times in the past couple years, and each time have not been able to find it anywhere locally.  Most recently was with my dodge truck, which uses carbon fiber syncros and needs a very specific fluid... cost me $160.  Actually just looked and I can get a quart of MT90 for $17, looks like this trans uses like 3 quarts or so, so I will be changing that out as that's not too expensive at all.  But I'm gonna try and get the trans working first so that the existing stuff will help flush crap out when I drain it.  

Edited March 30, 2016 by luseboy

[seattlejester]

I think my rebuilt motor was running pretty high in pressure at the beginning I'll have to go check if it was that high, I don't think so though.

 

That sounds like a pedal adjustment problem. Your going to have to stick your head under there and look at it to make sure it isn't binding before pushing on the rod. My problem came to a bad clevis, it was bending straight up instead of pushing and would only engage the clutch a little tiny bit after it bound up from being pushed up. If you can make sure that it is actuating the master in a linear fashion, you can adjust the engagement point by lengthening the rod so that it begins to push fluid sooner. Your going to need someone to watch the slave for you to tell you when the slave starts to move.

 

Another thing that was helpful on my swapped drive train when it wouldn't engage the clutch properly was a reverse bleed. I don't recall if you can do this with the datsun style slave, but you basically pump the slave to push any bubbles towards the top given the slave lives under the master. I do see that some slaves come with adjustable push rods, but the standard replacement one should have appropriate engagement. 

 

If the brakes work you can always have it dragged to a more friendly spot or trailer it if you have the means. If the car moves in first gear you can get pretty far without shifting, although that may not be good if your motor is rebuilt to rev it that high for that long. 

[luseboy]

I mean I know it's gonna run high when it's cold and the oil is thick, but it had the needle on the gauge pinned.  I may have a bad gauge or sending unit, but probably not as it's pretty consistent and is an autogage.  Unless maybe I plumbed the sender in a bad spot that doesn't give an accurate reading.  I am a little confused as to how it could be over 100psi of oil and not have anything leaking, but it may be because the motor was only running for a minute or a couple minutes at most.  I do also need to get the thing full of coolant before I can drive it, I'm assuming I just want to wait for the thermostat to open with the radiator cap off and fill it and let bubbles come up to the surface?  Or do I want to take the thermostat out and put as much coolant in as I can?  I know this isn't really anything to do with the transmission lol but you guys are being helpful.  

 

I haven't confirmed if the pedal is set up right and all that.  It's a new master, I think I re-used my old clevis/pushrod because I read the ones that come on the new masters are usually too short.  But I never measured pedal travel or anything, so I need to do that.  I will try lengthening the rod, and make sure it's working properly.  I'm really hoping that my problem isn't with the clutch itself, but I believe I matched the throw out collar to the pressure plate, aligned the disk properly, and everything was torqued to spec. The fork is on the pivot right, with the little spring guy engaged and holding it in place, so I believe my problem is in adjustment of the slave and/or master.  By reverse bleed do you just mean pushing fluid from the slave to the master?  I work as a bicycle mechanic and bleed hydraulic disk brakes all the time, and different brakes seem to take better to bleeding one direction or the other so I have bled backwards in the past.  I was actually thinking it would make more sense to bleed backwards anyways, as air moves up.  I don't see why I couldn't put a big ass syringe on the bleed nipple and push some fluid to the master... shouldn't hurt anything anyways.  Of course my problem could also be the adjustable slave rod I made, but I made it a good bit longer than the rod that came with the new slave so it should be long enough, we'll see.  

 

Luckily my daily driver is a big truck so I can tow it if I rent a trailer, but I could also just coast down the hill once I ensure my brakes are working properly.  My worry is getting back up it, but I suppose I could just use a chain from the back of my truck to the front of the datsun and get it up the hill if necessary, there isn't much traffic on that street.  The brakes bled out great and have been solid for the past two years, but I need to confirm that my booster rod was adjusted properly, hopefully the brakes don't lock up on me.  

[seattlejester]

Is it the correct sender? I just checked my start vid, and my stock gauge sat around 80psi, which definitely feels like it is on the high side, 100 seems real high.

 

Coolant: Fill it, let it warm up until the thermostat opens, fill it up again. Different permutations of cap on cap off, etc. Basically make sure there is coolant in there, let the car get up to temp to open the thermostat, once the level drops fill it up again. If you have a heater core make sure you have the heat on to fill it with coolant.

 

Check it before you go adjusting anything, assumptions are bad. 

 

Reverse bleed would indeed be that, but if your slave does not have a captive pushrod then what I am thinking might not work, the syringe might indeed be better. 

 

I'm still a bit bothered by the custom adjustable slave push rod. I guess if it returns to flush and is not partially engaging the clutch it should be fine.

[luseboy]

It is the one that came with the gauge when I bought it brand new a couple years ago, but perhaps something has gone bad.  I'm gonna start by pulling the relief valve cover off and cleaning out the valve, I read of a couple people having the same thing happen and that was all it was, so that's where I'm gonna start.  I'm concerned though that my oil galleys may be clogged, but if they were, I imagine there wouldn't be any oil flow and the top end would be making quite some noise, right?  There was no knocking or clicking or anything like that, so I assume oil is flowing.  I should have pulled the oil cap with it running to see if I could see any oil spraying out of the cam.  

 

By fill it up, you mean just the radiator right?  If so, that's what I had thought, but I want to leave the cap off so it doesn't develop pressure right?  I have a heater core with a little valve in the engine bay, so I'll make sure that valve is open.  

 

Well I was assuming the other day because I was just fiddling, but now I'm gonna go track down my problem.  I'm sure I will find out more when I measure the pedal travel.  

 

I feel pretty confident about my bleed but if everything else seems right and it's still not working then I'll give bleeding another shot.  What were you thinking?  And what do you mean by captive pushrod?

 

Haha ya honestly I should have left it alone, aren't the 280z slaves with the non-adjustable push rod supposed to be self-adjusting anyways?  I know I read a few topics on here or elsewhere that recommended having an adjustable pushrod and that just making a simple one was totally fine.  I'll check the FSM for the proper measurements for free play and travel and make sure I get that proper. It'll all work out somehow.  

[seattlejester]

Yea stop assuming...it is hard to do, but keep at it.

 

Take off the valve cover and see if any oil has made it up there. Assumption gone.

 

Can't suggest much on the oil pressure, not too familiar with all the little passages and what not, but either one of the passages right after the gauge port is blocked, the gauge sender is faulty, or the oil pump really is pushing that much pressure.

 

Some people keep it on to help the system develop pressure to get to temp faster, but then there is the added risk when you pull the cap off, those fancy caps with funnels seems to be a nice compromise. 

 

You need to fix each system here. You have concerns with your engine, concerns with the transmission, concerns with the hydraulics of the clutch. Pick one item and work on it, kind of hard to figure out what is exactly going on with what, and if you try to make theories with so many separate concerns it won't end well. 

[luseboy]

Ha well assuming is really all I have most of the time- I have one day a week to even look at my car as 6 days a week I am an hour away from it where I go to school full time, so I don't get a whole lot of time to diagnose my problems. 

 

I ran the engine again today and afterwards the cam was wet with oil.  I haven't pulled the cover off yet but I'm pretty sure there's oil up there. I will confirm this next time I run the engine.  From what I could find the oil pump can put out that much pressure, I'm just confused as to why I don't have any seals blowing out.  That being said I do have some oil dripping down from two of the bolt heads on my oil pump, so I'll have to figure that one out too.  

 

Lol no fancy cap for me, I'll just keep it off and wait.  Gives me some good time to confirm I don't have any exhaust or vacuum leaks and make sure my timing is set and what not. Next time I need a new cap I'll look for one of the fancy ones.

 

Ya I totally hear you, I guess I got a bit excited because I hadn't been doing anything with the car for so long and all of a sudden I am, but of course I have some things to address. I still haven't had a chance to really diagnose my problems but things are getting there nonetheless.

 

Today I took some time to do some silly things that made me feel more motivated, like putting on the door panels and headliner and cleaning some stuff up, and testing out some of my electrical components I hadn't really had a chance to do (like my dapper headlights that are extremely bright) anyways in the process I pushed the car out of the garage into the driveway, and what do you know? All of a sudden the damn thing would hit all gears no problem, with a great shifter feel.  Of course once I rolled it back in to the garage, it would no longer shift into the gears but at least I know it's able to do so when the output shaft gets spun.  I'm feeling hopeful that it'll come around.