Driveshaft retaining pins stuck, and punch tool stuck too

[cazna52]

I have made a very very bad mess of removing the driveshaft retaining pins from my car.

I used a narrow punch to remove the inside pin and that went fine. I then used a larger diameter punch to try to remove the outer pin but that was where my troubles started.

I assume the punch managed to slip inside the pin somehow but in any case the punch got stuck. I tried using vice grips to pull the half exposed pin from the other side so that I could punch back through but the pin snapped off inside.

I then tried for two days to pull the punch out with vice grips and rocking the gearbox side to side to wobble it out but eventually the punch snapped as well leaving the shaft of the punch in the hole also.

The narrow punch that fits inside the outer pin was too short to get to where the other punch was stuck so I had the brainwave of putting the inner pin back in to try to push the punch out. Now the inner pin is stuck in the hole also.

I think the situation is something like this now.

Uploaded with ImageShack.us

Can anyone think of any way I can get out of this mess?

[rogerch]

Is the gearbox still in the car ?

If not I would strongly consider taking to an engineering shop. Don't quote me as I've never done it but I think that either the pins or the holes are tapered.

I can't give you dimensions but I would have a punch made up the same diameter as the ID of the outer pin, with an end for "hitting"

And another the same diameter as the OD of the outer pin.

Having said that the engineering shop may well be cheaper. There are some very fine engineers on the South side of Sydney, if you know anyone in the Lotus Club I'm sure they'd put you onto one.

[andydclements]

I can only suggest purchasing a longer thin pin punch or risk it with a fairly hefty mail, just to get that larger punch out. I've not broken a punch off in them but have had them get suck.

[Sparky]

Are you taking the gearbox out? If so, undo the boot and pull the yoke and spider apart. Then you can take the box out and sort it at your leisure.

[Vulcan Grey]

try holding Dry ice on the punch to get it to shrink enough to pull out with a slight wiggle motion. Can you still get some vise grips on the broken end of the punch?

Also use some lube...

Edited September 21, 2011 by Vulcan Grey

[TAR]

the punch will be made from hardened steel so will be brittle but almost impossible to drill out, so you are limited to finding a way of either pulling or pushing it out.

[cweeden]

Perhaps you could use a freeze spray on the punch or smaller roll pin as an alternative freeze source for Travis' suggestion above.

Roger the Dodger, "Is the gearbox still in the car ?". I am not sure you have thought this through.

[lotus4s]

The reason that the roll pin initially got stuck is that it is bent inside the output shaft and that was the beginning of your problem. Jamming more pieces into the hole just compounded the problem. I feel for you as I've been right where you are now.

After breaking off punches and drill bits etc, I was finally able to get the mess apart by using a diamond tip bit in a Dremel tool and carefully grinding the pins out enough to be able to separate the cv axle from the output shaft. It was a slow, frustrating and tedious job that took several hours to do.

If none of the suggestions work for you, your pretty much stuck with removing the gearbox and taking it to a machine shop as Roger mentioned...

[cazna52]

Thanks for the advice guys. I am thinking of maybe trying a combination of a few of the suggestions. The punch I used before was smaller than the OD of the outer pin but I thought it was bigger than the ID. I have another punch that is the same diameter as the OD but I didn't want to use it to start with because I thought it would get stuck, yes I know, I was wrong.

I am thinking of grinding off the exposed parts of the pins then trying to drive everything out with the punch matching the OD of the outer pin. I will also try to cool down the broken punch before doing that.

If that doesn't work I think I will have to try to get the gearbox out with the driveshaft still attached and take it to an engineer as Roger suggested.

The engineer will no doubt be shocked at the mess I have made, lol.

[jonwat]

The engineer will no doubt be shocked at the mess I have made, lol.

Yeah, bit think just how much fun he'll have telling his mates all about it down the pub that night, he'll be the toast of the local mechanics

[rogerch]

Roger the Dodger, "Is the gearbox still in the car ?". I am not sure you have thought this through.

Though I have "not yet" taken the gearbox out of an Esprit, I can see no obvious reason that it should not come out complete with drive shafts as I had no problem with removing the hubs, leaving the shafts dangling.

Indeed this could turn out to be Justin's only option.

If I'm wrong and it can't be done, OK, but I'd like to know why if only just for curiosity.

[cazna52]

I am pretty sure that can be done, and I have one shaft off already so it would only be one sticking out that I would have to deal with. Still I would prefer to get the shaft disconnected first but leaving it connected is plan B.

[ramjet]

From what I can gather, you have the centre pin out? Yes? Could you try punching the broken punch back out with a smaller punch that will go inside the outer pin with enough clearance to not jam? Use penetrene oil down the driveshaft pin and slightly rotate the punch between blows. Go gently at first as you will be using a hardened steel punch on a hardened steel punch which can shatter. Remove the punch and check it regularly to see if anything is going pear shaped on you.That might at least get you back to just the outer pin in the driveshaft. You may then be able to get at the outer pin again with a new punch.

Failing that, as said above, out with the box so you can get to it in a more controlled manner.

Best of luck with it.

[cazna52]

The centre pin was stuck in there too, but I managed to get it out tonight

I was able to get some vice grips on the end of it and use a screwdriver to lever it out. This is a great breakthrough. If I can find a long thin punch I should be able to do what Michael suggests and punch the broken punch out through the hole in the outer pin.

[ramjet]

Though I haven't seen this setup, I think that the outer is probably a rolled pin? If it is, it is possible to collapse the leading edge of the pin end slightly. This will either break the pin away from its friction surface allowing you to possibly get it out, or may give you a more solid surface that you can hammer away at with a punch as the hole through the pin is now closed up slightly. Don't know how many times the fitters who taught me my trade left me with the job of removing a seized rolled pin. A brass dolly may also be something to try as it is less likely to fail like your hardened punches.

Just tread with caution.

[Sparky]

I say again - it's far easier to separate the yoke from the spider on the inner joint (it just pulls out), thereby negating the worry of having the shaft dangling during gearbox removal. Roll pins need not be touched (until you have miles of access on the bench). Refitting the driveshaft is then simply a matter of pushing the spider in and securing the gaiter.

[internets]

I say again - it's far easier to separate the yoke from the spider on the inner joint (it just pulls out)......

He is right you know much easier then don't even need to touch the pins!

[mr.oogieboogie]

i had a punch snap when doing the clutch on mine cost me a couple of hours but managed to hammer it out using a smaller punch

[cazna52]

I got everything out

After I pulled the center pin out I was able to knock the stuck punch out from the other side through the outer pin using some better, longer punches. They cost $92 but it was certainly worth it to have some good punches to work with.

Now the gearbox is out and the clutch also. The clutch had lost all the friction material from one side but thankfully it was from the pressure plate side and the flywheel looks perfect.

My next challenge is taking the flywheel off to fix a leaking rear crank seal behind it. The bolts are seized pretty tight as you would expect and the flywheel wants to spin so they have been giving me some trouble. Spent a few hours today with a socket and hammer trying to shock them free without any luck.

Does anyone know a trick to stop the flywheel spinning?

[rogerch]

Put a stud through one of the bell housing bolt holes then wedge a cold chisel or damn big screw driver against the starter motor ring gear.

When you've done all this how about publishing the dimensions of the requisite punches. I may have to do this myself one day.

[mc21.8]

starter ring gear on flywheel lock it up with tyre lever or large screwdriver ect

[Rich H]

Yep, large screwdriver in the starter ring.

[cazna52]

Cool, thanks, I will give that a try tomorrow night.

With the sizes of the punches I think from memory I used 3mm and 6mm. I just used the largest diameter that would fit. I will double check it tomorrow. The main thing though was that they were long punches, the $10 set I bought to start with were too short, an extra couple of cm of length costs $92 for the set, but that extra length lets you punch the whole way and to reach any blockage like my broken punch.

The other thing that I would say is the most important tip I have picked up from this experience is to rotate the punch after each strike like Michael suggests so you know when things are going wrong before you get too stuck.

[mc21.8]

The pitch changes when fowling ect .and should be removed both together..<there is a lotus tool for this>

The halfshaft hole is offset.and pins are replaced at <180> degree off each other,and sealed at ends with silicone or equvelent.

[ramjet]

I got everything out

...

And that is why this is such a great place for info, though I would highly recommend asking first next time 'cos then Sparky would have told you what he said in his post which may have made the whole job a lot easier for you.

Betcha don't stop to ask for directions when you're lost either hey?

ps. I'd have started on it without asking first as well.