Flywheel ring gear replacement - Help needed

[smclaren]

Hi Guys

I need to replace the ring gear on my truck (starter has chewed it up). I could appreciate some help in the planning before I attack it as I've never had to replace a ring gear on anything before.

So I am guessing ... drive shaft off (2wd), squirt clutch slave off, speedo cable off, cab floor mat out, inspection cover off, jack under the NP435, bell housing bolts out .... gracefully drop the gear box on my mates head ... (just kidding) Anything I missed ??

So ... clutch off, flywheel off ....Now what ??

How do I get that sucker off (it's rooted so I am thinking just smash, cut, lever it off ??)

Whats the correct way and the short cut way of getting them on? Oh ... it's a 240ci.

Any proceedures, hints, tips, gotcha's all greatly accepted.

Thanks

Steve

[convincor]

air hammer works good. Keep it moving in a circular motion so the gear comes off somewhat evenly.
Heat the new gear with a torch and drop it on. If it doesn't fully seat again use a hammer to seat it.
Torch method- http://www.youtube.com/watch?v=_XW1-5mPSsY

Oven method- http://www.youtube.com/watch?v=eexErz03 ... re=related

[wickedinhere]

I just did one a month ago i used a punch and hammer and went around hitting it till it came off.
I put my flywheel in the freezer for an hour then heated the new ring gear evenly and it dropped right on.

[flyboy2610]

I just did one a month ago i used a punch and hammer and went around hitting it till it came off.
I put my flywheel in the freezer for an hour then heated the new ring gear evenly and it dropped right on.

That's how it's done. Freezing contracts the metal of the flywheel, heating expands the ring gear. The size difference allows the ring gear to drop onto the flywheel. Instead of using a torch on the ring gear, you might try cooking it in a very hot oven for an hour or so. The heat distribution in the ring gear would be more even than a torch.
Good luck!

[smclaren]

Quick question ....

Do I need to drop the gear box first and seperately from the bell housing, or do I remove the gearbox (NP435) and Bell housing as a unit?

[Dragon]

You can do them at the same time but it makes it real heavy and harder to realign the clutch.

[fordman]

i'd drop the trans as one piece. and then take the bellhousing off.

[smclaren]

Thanks Guys, I ended up splitting the box and bell housing and removing each seperately. I am doing this by myself so it made it easier. Trying to get the bell housing over the cross member while attached looked daunting.

It's gotten dark (and cold) so I have finished for the day. Next weekend I need to remove the flywheel. Any tricks on how to stop the flywheel spinning whilst I attack the bolts ?(i dont have air tools).

[fordman]

maybe you can put a block of wood in the fan belts. or put a socket and breakover bar on the crackpulley bolt. or you could get on of those flywheel turning tools that may hold it . if it doesnt hold it in the wrong direction. those bolts are probably going to be real tight. and probably have some loctite on the threads. or put the bellhousing back on with out the pressure plate and use a screwdriver to wedge into the teeth against the bellhousing. i'll think of more methods later.

[lee_ford]

Any tricks on how to stop the flywheel spinning whilst I attack the bolts ?(i dont have air tools).

This method is kind of hard to explain so bare with me.

I took a piece of flat steel about 1/4+ inch thick and 1/2 to 1 1/2 inch wide and 18+ inches long. Grind the edge flat if needed so it will not slip off the side of the bolt head. Then place this between two bolts on one side and between the 2 bolt heads on the other side. Rotate engine so this bar is wedged against the frame or a long bolt inserted in a bell housing bolt hole. Use a socket and break-over bar on the bolt not involved in this. Break this bolt loose only. Do not screw out too far so it can be used to bind the flywheel while loosening the rest. Once all bolts are loose you got it made. To reinstall just do the reverse. Snug all the bolts then use the bar brace while tighten them. Be sure to really grunt when tightening or use a torque wrench.

If the bolts are inset to far to use a flat bar you can put a slight z bend in it if needed.

[lee_ford]

Another way is to use two break-overs and sockets. Use one on one bolt prevent flywheel from turning and the other on the bolt you want to loosen. As you loosen one you will be tightening the other. But, as you do this use a bumping motion on the bolt you want to turn and have a steady pressure on the one holding the flywheel. The bolt you are tightening will not get as tight as the one you are loosening and will be easier to loosen when you get to it. If needed use a hammer on the break-over on the bolt you are working on. The bumping will work harder on that bolt than the one used to hold the flywheel in place. This works either way, going on or off. When reinstalling, just be sure to go around the flywheel until ALL bolts are good and tight.

Also when doing the final tightening, place your socket on the bolt away from your wrench. This will give you more leverage against the turning motor.

Here is a quick pic to explain this and my last post…

Flywheel.jpg

[Dragon]

I do it so the torque wrench goes across the center to the opposite side directly through the center line. This is an old trick. Someone also makes a tool that a bell housing bolt pass through that has two teeth the catch the flywheel teeth and hold it.