Trouble splitting the manual 5 speed from the engine.
 

Hi folks, I have followed the manual and believe all is ready to split the engine and the gearbox. I do not want to remove the engine just the transmission. Reason is a suspected rear main seal needs replacing. The manual says not to wiggle the transmission from side to side or up and down as it could damage the crank position sensor.

Just wondering if there are any common mistakes preventing seperation of engine and gearboxes. Perhaps i am being too careful. Are there any good techniques for cracking the tranny?

Anyone identify any common gotchas?

Many thanks, I have to complete this within the next 48 hours, as I am camping at a mates house and using his tools. His wife will throw me out after that. Lol

1999 NB8A.

Chris

Chris

Take the crank sensor off and then wiggle it?

I'd think wiggling the Tranny and having the crank move enough to damage the sensor would mean a bad thrust bearing or something.

Thanks mate,

A friend suggested the same. Can you tell me, when I put the sensor back on do I need to recelebrate it?

I'd think the problem with the wiggling is smashing the CAS repeatedly into the firewall. Shoving the crank back and forth would not damage the cranksensor (if there's one in the first place).


Quadruple check you got all the bolts out and pry around with a large flathead screwdriver. It will separate eventually.

Also, yes. A finished motor/tranny swap would be cause for celebration :party:

remove all bolts holding it to motor.

Then hit with hammer.

You could try "being a man".

Thanks everyone..... Well almost everyone.

i had serious advice. get it off yet?

Yes you did. About to start. Just removing the gear leaver before we try again.

Sometimes the case hangs on corroded dowels.

cam angle sensor :ne: crank angle sensor.

OP- be mindful of all the bolts, and like Hussie said, the dowel pins can keep things from going smooth. Use a good long-handled scredriver or prybar to get the seperation process started.

And the winner was the old last unseen bolt. I now have seperation, clutch off and flywheel. About to have a coffee now. Anyone want one? Lol

Not much in the way of oil leak from the rear main seal area but there was a lot in the bell housing. Is it poss that the oil came from the gearbox? Not the pin hole was showing signs of a small amount of leakage. Go figure

Yes to leakage from the front of the transmission, at the input shaft seal. It's a recommended replacement item when pulling the trans for a clutch swap (as well as the rear main).

Edit: Seal (17-131). My '92 trans has a gasket behind the TOB sleeve, but yours apparently does not based on the image below.

https://www.miataturbo.net/attachmen...1&d=1359939142

I think there's a paper gasket behind that flange as well.

OP said crank sensor, but did the book said CAS? I never though about damaging the CAS when wiggling a transmission around. I've also never removed it while it's still in the car.

Does a '99 have a cam sensor on the back of the head? I have a BP4W on my car and the bellhousing is a mile away from anything but the reroute neck at the back. EGR maybe (if I had it).

My vote would have been for a bolt that was missed BTW so I haven't gone full retard quite yet... :loser:

Well what a day! I am a crap home mechanic. I have the seal in and just finished torqueing the bell housing bolts. I am having trouble remembering which bolts go back into the starter motor. I have three 12 mil bolts middle bolt is in fine, the top bolt does not go in all the way. It hangs out 3mm. The bottom starter bolt looks like it needs a nut on the end. Any on confirm the bolt and bracket placement for mounting the starter?

I'm tired

One of the starter bolts (IIRC) takes a nut. If it isn't a starter bolt, it is one of that side. If a bolt is too long, try it in a different bung. The long ones go in the top IIRC. Get them all started before you torque any of them down.

Well Folks, the work is complete and thanks everyone for your help but there is bad news.

- Oil leak is still there (small) and it leaks from the base bell housing to engine join and nothing from the pinhole yet. What a killer! I replaced the gearbox front sea and the engine read main. I did not replace the oil pan seal because it looked like oil was leaking from the original rear main.
- Now it seems there is a new metal noise coming from one front pulley at idle.

Beats me how I managed to make that happen. I think the noise is from the center top pulley area. Any know weaknesses in that area?

One positive, I've learned a lot about the drive trans of the car.

Folks, I guess it's a big job to remove the oil pan seal. Is it as big as the job I just completed?

A very weary,
Chris

Unless I'm mistaken, it requires removing the engine.

Why you ask? Because that metal piece seals against the oil pan. And in order to remove the oil pan, you need to either remove the subframe and work on your back, or do what everybody else does and remove the engine.

But don't listen to me, last time I suggested removing the engine it was the damn cam seals.