5th gear Detent screw removal method

[Some guy]

So i have the problem of 5th gear not holding. I think it is a problem of the Detent not holding 5th gear.

I have tried to remove the screw with a flat head screw driver, but to no avail.

Does anyone have a good way of removing the screw?

I with thinking of cutting a quarter in half and holding it with a pair of pliers. I was hoping someone had a better method.



(This is a post with a picture of the problem area)

http://dmctalk.org/showthread.php?5422-Weird-sound-in-5th-gear&highlight=popping+gear

[DMC5180]

So i have the problem of 5th gear not holding. I think it is a problem of the Detent not holding 5th gear.

I have tried to remove the screw with a flat head screw driver, but to no avail.

Does anyone have a good way of removing the screw?

I with thinking of cutting a quarter in half and holding it with a pair of pliers. I was hoping someone had a better method.



(This is a post with a picture of the problem area)

http://dmctalk.org/showthread.php?5422-Weird-sound-in-5th-gear&highlight=popping+gear


You can grip the edge of the screw(CAP) with a vise grip or pliers. It will crack loose then unscrew with fingers. Teeth marks left on the edges of the CAP are mostly cosmetic.

CAP>SEAL WASHER (REUSABLE)>SPRING>BALLBEARING.

The ball should fall out, but you might need a stick magnet to pull the ball loose and oil may run out if you have not drained the trans. I highly doubt this is your problem but it is plauseable the Spring has collapsed I'd think that to be extremely rare. If anything The Fifth gear fork could be bent, If that were the case it would likely not allow full fifth gear slider ring to engage fully. The Good thing here is that all the fifth gear parts are in the End Cover so you wouldn't need to split the case,. Just pull the End cover and inspect. Requires a NEW cover gasket IF you decide to do that.

[Some guy]

So i finally got around to checking the Detent screw bearing. It was perfectly fine. (that is good, but i really was hoping this was my problem.)

If the 5th gear fork is bent, is it easy to replace? Is there anything else inside there i should look at or replace?

How do you think it got bent?

Do i need to replace it or can i just bend it back into place?

[David T]

So i finally got around to checking the Detent screw bearing. It was perfectly fine. (that is good, but i really was hoping this was my problem.)

If the 5th gear fork is bent, is it easy to replace? Is there anything else inside there i should look at or replace?

How do you think it got bent?

Do i need to replace it or can i just bend it back into place?

I have successfully straightened bent 5th gear forks but I heat them up before trying to bend them straight. If you do it cold you will probably crack it. IMHO they get bent from forcing into 5th gear and things are not adjusted right. While you are there make sure the nut holding the gear on at the end of the shaft is tight. Use the casting lines on the side of the fork to see when it is straight.

[Nicholas R]

There is also a wire spring inside the synchro coupler for 5th gear that helps to keep the shift mechanism tight. It is item 8 on this page: http://store.delorean.com/c-288-4-1-2-gears.aspx

Might want to check it for damage. By removing the back cover off of the manual and removing the input shaft nut, you can completely remove the 5th gear assembly (gear, selector, fork, dog gear, and all)

Edit: I don't have a good photo of the assembly together but here is one of an assembly I have taken apart. (Disregard all of the teeth missing from the 5th gear) The circular wire is the spring, it goes inside of the 5th gear assembly inside of the part that the coupler slides over when you engage the gear. The 3 places where the wire bumps outward engage with the teeth of the coupler to apply outward pressure on the coupler to help hold it in place. If this piece were missing or damaged, you would have a lot less holding your 5th gear selector mechanism in place when the gear is engaged.

Note, the far left gear is the output shaft 5th gear, the second from the left is the input shaft 5th gear (it's double thick as it has the selector teeth on it. The gear at the bottom is the dog gear that actually engages the input shaft, and the brass ring is the synchronizer ring.
http://i565.photobucket.com/albums/ss94/NicholasRoedl/Transmission%20Photos/FBC86D8D-9589-4F0B-BFC5-01F0E0AB22DB_1.jpg

[Some guy]

So the Detent screw was not the problem. It really didn't make a big difference.

I am slowly working up the courage to pull the back cover off the transmission. I am not sure if i am ready to pull the whole 5th gear assembly out yet. but i have to do something. 5 gear will just not stay locked in.

If it is the "Fifth gear fork" bent. Is it easy to see it bent? Do i need to remove the 5th gear assembly to fix it?

When you talk about heating it up, would a propane torch be enough heat?

[David T]

So the Detent screw was not the problem. It really didn't make a big difference.

I am slowly working up the courage to pull the back cover off the transmission. I am not sure if i am ready to pull the whole 5th gear assembly out yet. but i have to do something. 5 gear will just not stay locked in.

If it is the "Fifth gear fork" bent. Is it easy to see it bent? Do i need to remove the 5th gear assembly to fix it?

When you talk about heating it up, would a propane torch be enough heat?

If you look at the fork from the side there are casting lines along the edge. They should be straight and it will be pretty obvious the fork is bent. A propane torch will not get you hot enough but you must be careful not to overheat the fork or you can melt it. A Tempelstick is very useful if you are not experienced with doing this. A Templestick is a marker that leaves a mark on the metal and melts at a specific temperature. Or you can use an IR non-contact thermometer. The trick is to heat it to a certain temperature and get it evenly heated. Before getting hung up on how you are going to fix it I would first verify that the fork is actually bent. You can also hold a small straightedge like a 6" steel ruler alongside and see if it looks straight. Taking off the back cover is not difficult. Just drain the oil out FIRST! The fork gets bent by someone forcing shifts. Possibly because the linkage is out of adjustment. The other possibility is the nut holding the 5th gear loosened and the 5th gear moved making it hard for the fork to reach it and get into that gear. Once you get that cover off it should become obvious what you need to do.

[PJ Grady Inc.]

This problem is not uncommon and is almost always a bent fork probably sustained when the car was driven home with a leaky hydraulic cylinder and the clutch was not fully releasing between shifts. If the car has issues with 2nd gear not engaging easily(esp.when cold) or popping out of 2nd gear the stop pin for that gear may be sheared which would tend to corroborate my theory. Of course we must allow for a ham fisted "speed racer" spending time at the helm or the primary shaft nut backing off as David mentioned.

New forks are not readily available and straightening is trickier than it may seem because it's usually pretty subtle visually. If the fork contact points at the gear are excessively worn that is the best visual clue and this wear/clearance would have to be added back to the fingers for a proper repair. That would be tricky as the melting point of brass again comes on suddenly as pointed out by "The Guru".

I have not yet personally tried to have this done but have a pile of old forks to experiment with should the need arise. Another project on the horizon but I'd rather check across the pond for any old inventory before going that route.
Rob



So i finally got around to checking the Detent screw bearing. It was perfectly fine. (that is good, but i really was hoping this was my problem.)

If the 5th gear fork is bent, is it easy to replace? Is there anything else inside there i should look at or replace?

How do you think it got bent?

Do i need to replace it or can i just bend it back into place?

[Some guy]

ok being brass it totally makes sense why it bent.

Can i get away with one of those liquid gasket like permatex Silicone Gasket Maker?

i have a feeling i will have to take off the cover a few time to figure it out.

[David T]

This problem is not uncommon and is almost always a bent fork probably sustained when the car was driven home with a leaky hydraulic cylinder and the clutch was not fully releasing between shifts. If the car has issues with 2nd gear not engaging easily(esp.when cold) or popping out of 2nd gear the stop pin for that gear may be sheared which would tend to corroborate my theory. Of course we must allow for a ham fisted "speed racer" spending time at the helm or the primary shaft nut backing off as David mentioned.

New forks are not readily available and straightening is trickier than it may seem because it's usually pretty subtle visually. If the fork contact points at the gear are excessively worn that is the best visual clue and this wear/clearance would have to be added back to the fingers for a proper repair. That would be tricky as the melting point of brass again comes on suddenly as pointed out by "The Guru".

I have not yet personally tried to have this done but have a pile of old forks to experiment with should the need arise. Another project on the horizon but I'd rather check across the pond for any old inventory before going that route.
Rob

The forks are actually bronze and they can be successfully welded (it's called brazing) if necessary. They are more brittle than brass so they will break if you try to bend them without heating them to just below the melting point. Any good welding shop should be able to fix them. If the fork is bent it can be "subtle" but if you concentrate on the casting lines on the edge you can tell easily. As for the roll pin, if the transmission is out and apart you replace it "just because". You can't get to it from the end cover but you CAN do the fork and the end nut. As for "Ham Fisted" if the shifter has been forced we also see the gate for reverse getting broken from being forced because a driver didn't know how to unlock the reverse gate. It's never "just" one thing. If you have problems with shifting you should go over the whole shifter mechanism, lubricating, adjusting, and replacing any worn or bent parts. The little rubber bushings always are worn allowing sloppiness (lost motion) in the shifter. That can lead to lost shifts and forcing things too. Get that end cover off and see what you have. Take a picture and post it.

[PJ Grady Inc.]

Dave you've actually seen a broken reverse gate? Talk about ham fisted that would be double jumbo heafer fisted if you ask me!
Rob


The forks are actually bronze and they can be successfully welded (it's called brazing) if necessary. They are more brittle than brass so they will break if you try to bend them without heating them to just below the melting point. Any good welding shop should be able to fix them. If the fork is bent it can be "subtle" but if you concentrate on the casting lines on the edge you can tell easily. As for the roll pin, if the transmission is out and apart you replace it "just because". You can't get to it from the end cover but you CAN do the fork and the end nut. As for "Ham Fisted" if the shifter has been forced we also see the gate for reverse getting broken from being forced because a driver didn't know how to unlock the reverse gate. It's never "just" one thing. If you have problems with shifting you should go over the whole shifter mechanism, lubricating, adjusting, and replacing any worn or bent parts. The little rubber bushings always are worn allowing sloppiness (lost motion) in the shifter. That can lead to lost shifts and forcing things too. Get that end cover off and see what you have. Take a picture and post it.

[David T]

Dave you've actually seen a broken reverse gate? Talk about ham fisted that would be double jumbo heafer fisted if you ask me!
Rob

What I have seen is the roll pin broken. When that breaks that disables the lock-out. The gate mechanism isn't actually broken. It doesn't happen in the Delorean but I have seen where the gearshift lever breaks from being forced. On an old pick-up one time I was driving it and the whole dam gear lever (about 3 feet long) came up out of the floor! I had a lot of fun getting that thing back in and trying to drive back without having it come out again! Point is a new owner really doesn't know how the last owner treated the car. Some owners flog it hard and don't fix anything. New owner now wants everything to work. It can take a LOT of work to fix everything and undo all of the previous damage.

[PJ Grady Inc.]

Exactly as I would expect as I've seen broken roll pins and levers but never a bent gate....yet!
Rob


What I have seen is the roll pin broken. When that breaks that disables the lock-out. The gate mechanism isn't actually broken. It doesn't happen in the Delorean but I have seen where the gearshift lever breaks from being forced. On an old pick-up one time I was driving it and the whole dam gear lever (about 3 feet long) came up out of the floor! I had a lot of fun getting that thing back in and trying to drive back without having it come out again! Point is a new owner really doesn't know how the last owner treated the car. Some owners flog it hard and don't fix anything. New owner now wants everything to work. It can take a LOT of work to fix everything and undo all of the previous damage.

[Some guy]

so i have the cover off. I almost lost the detent ball.

So the fork is bent, it is really bad.

How do i get it off? Do i drill out the metal "cotter pin" or do i remove the bolt on the upper part of the transmission?


33349

[DMCMW Dave]

so i have the cover off. I almost lost the detent ball.

So the fork is bent, it is really bad.

How do i get it off? Do i drill out the metal "cotter pin" or do i remove the bolt on the upper part of the transmission?


33349

Remove the large nut and lift the fork off with the gear set. You will need to knock out the cotter pin if you happen to buy just the fork, but if you find a good used assembly you'd just drop in the whole thing.

[Some guy]

how do i keep the nut from spinning?

Should i put the parking break on or should it be in 1st gear or both?

[DMCMW Dave]

how do i keep the nut from spinning?

Should i put the parking break on or should it be in 1st gear or both?

Put the trans in two gears at the same time, i.e. move two of the shift rods out of neutral. This will lock the gears and nothing will turn.

[Some guy]

Thanks for all your help

I was able to remove 5th gear and slightly bend back the fork. i didn't want to push it since there was so much talk about it breaking.

After i put it back together, it seems to be better. i still had it pop out of gear once, but that is much better then it was.

I am going to wait till it gets bad again and replace it with the updated fork on DMC's website.

[Josh]

just noticed this thread and i thought i would chime in. I had a problem with my transmission not going into 5th. Everything worked great until i spun the wheels from a stop sign in the rain, heard a clunk and no longer had fifth gear. I removed the transmission while doing my swap and it would not go into fifth. Even with the rear cover off moving the rod. Then, one day i finally got it to go into gear. not sure what i did.

So my question is, would my fork be bent as well? would like to get this sorted out before i put my transmission back together.

[PJ Grady Inc.]

Possibly the fork is bent as this is fairly common. Don't know how you could damage it pulling away from a stop unless you somehow jambed it into fifth.
While repairing them has been discussed here I would prefer using a new part and I have a line on some forks overseas. They've been pretty much unavailable stateside for many years. If all goes well I could have some in a few weeks.
Rob


just noticed this thread and i thought i would chime in. I had a problem with my transmission not going into 5th. Everything worked great until i spun the wheels from a stop sign in the rain, heard a clunk and no longer had fifth gear. I removed the transmission while doing my swap and it would not go into fifth. Even with the rear cover off moving the rod. Then, one day i finally got it to go into gear. not sure what i did.

So my question is, would my fork be bent as well? would like to get this sorted out before i put my transmission back together.

[David T]

Possibly the fork is bent as this is fairly common. Don't know how you could damage it pulling away from a stop unless you somehow jambed it into fifth.
While repairing them has been discussed here I would prefer using a new part and I have a line on some forks overseas. They've been pretty much unavailable stateside for many years. If all goes well I could have some in a few weeks.
Rob

Could be you were not all the way into 5th and when you spun the wheels you bent the fork as it popped out of gear? Just guessing here. In any case it is probably bent. As a vender Rob has a problem selling used parts, he has to warranty them, much safer to sell new ones. As an owner you can do anything you want including trying to straighten a used part. There is the possibility that even if you straighten the part it is now weaker and may bend again easier. A new part is always preferable as long as one is available.

[Josh]

Possibly the fork is bent as this is fairly common. Don't know how you could damage it pulling away from a stop unless you somehow jambed it into fifth.
While repairing them has been discussed here I would prefer using a new part and I have a line on some forks overseas. They've been pretty much unavailable stateside for many years. If all goes well I could have some in a few weeks.
Rob

I was in first only! that is what confused me. Ill check it out and see if it is indeed bent. Ill keep in touch if it is.... Not looking forward to the transmission rebuilt, probably the hardest part of my swap FOR ME honestly lol.

[PJ Grady Inc.]

I figured if you managed to spin a wheel at all it would have been in 1st and even that usually requires some water with a stock car. No chance of damaging 5th that way. But I just had a thought...check your shift cable adjustment because you may have disturbed that with your "bad boy" antics.
Rob


I was in first only! that is what confused me. Ill check it out and see if it is indeed bent. Ill keep in touch if it is.... Not looking forward to the transmission rebuilt, probably the hardest part of my swap FOR ME honestly lol.

[Josh]

I figured if you managed to spin a wheel at all it would have been in 1st and even that usually requires some water with a stock car. No chance of damaging 5th that way. But I just had a thought...check your shift cable adjustment because you may have disturbed that with your "bad boy" antics.
Rob

LOL. I will have you know I could break the tires loose with the 3.0 with somewhat ease!

The linkage is what i inspected first while the car was still all together. When I pulled the transmission it still would not shift into gear, so that eliminated the linkages.

[PJ Grady Inc.]

Gotcha.....sounds like fork time. I'll let you know if/when my ship comes in!
I forgot you have that you had that 3.0 in there but I guess the engine just had a growth spurt right?
You'll be needing a sound 5th gear for that engine not a straighted fork to hold 300 or 400 HP.
Rob



LOL. I will have you know I could break the tires loose with the 3.0 with somewhat ease!

The linkage is what i inspected first while the car was still all together. When I pulled the transmission it still would not shift into gear, so that eliminated the linkages.