Thread: Engine Balancing? - Broken Flexplate

Originally Posted by PLR

G`day ,

Pretty common to split a TC , the way to mod for high and low stall ETC.

I would pressume they cover there work and you`ll have the bits to check .

I can get how the spigot as is may break the drive plate and has to be rectified but i don`t see how it is going to shape the broken drive plate you have .

Was the first broken drive plate the same shape as the current one or was it still flat ? ( manual says there`s paint on one side and they only go one way )

From your first , does it explain the vibration ?

You had it with both or do you consider the first was already broken when the engine was fitted ?

It seems , you say only 50km when the head came off and the vibration was first noticed , if this is right and only one head came off , there will be a possibility that a different thickness gasket or head was fitted and this could cause a roughness which may appear to be a balance problem .

I only suggest the above because again i would pressume that in the 50km of the first run it would have been monitered very closely and if the vibration was there you would have noticed .

Peter .

The TC has to be split to balance it, as its too hard to drain the oil completely and put pressure on the lock up clutch, and balance it all at the same time.

When i first installed the new engine, i did the TC bolts up to the RAVE spec of 45nm and not 65nm as per the TSB that was issued. Hence the first plate broke because it fretted around the bolt holes. The way this first plate split was entirely different to this latest one. As you can see form the pics, this one has broken from halfway between the bolt holes into nearly four equal pieces, where as the first plate you could see it broken where it had fretted around the bolt holes.

I'm about to order the new drive plate so that we can fit it to the spigot aligner on the bench and mesh it up with the TC. That will prove that the TC is not flexing the plate at all.

Your pretty much on the money about the vibration, which i dont believe was there upon first starting the engine. I'll try this, and if the vibration is still there i'll dig a little deeper into the idea of the head. Basically, once i'm done with the alignment of the TC and gearbox, then it has to be something else.

From here i will ensure everything is aligned and tripple checked. Refit the motor, and replace the Harmonic Balancer. If there is still a vibration, well we'll cross that bridge when i come to it.

This whole scenario has been a disaster. If you have work done by professionals you expect it to be done properly. I have spent nearly $10,000 on just the Gearbox and motor, thats not a small amount of money to put into a car. I would expect it to be pretty much Mickey mouse.

Anyways, i'm taking it one step at a time. Piece by piece. The car has to be fixed and sold by April. So who knows, there might be a bargain for someone who has access to a decent workshop.

Originally Posted by Blknight.aus

I'd be flipping the TC off, with a busted flex plate and incorrect support from the spigot it will have been trying to run off center and will potentially have damaged the internals of the lockup.

Id also be having a very close look at the autos pan and filter and if theres any evidence of metal or lockup material having a good look at the front of the auto.

Spot on,

The TC guys, are fully checking it for wear and damaged internals including metal pieces. When i get back to melbourne, i'll be going over the Oil seal on the front of the box and going from there.

Can you see any harm in dropping the pan and checking the filters before putting the TC back in?

SO finally its time for an update, with pics.

The TC has been completely rebuilt and balanced. They have fitted a new larger 34.5mm spigot and machined out the Spigot Aligner to match. The overall finish of the TC is so much better than the original gearbox build.



Here is the complete setup on the Bench. TC through to Spigot Aligner including flex plate.




As the ringgear had to be replaced due to the damage, i have had the new 2nd hand one balanced, luckily, as it was a fair way out. So maybe this was another cause of the vibration.

I'm now waiting on a new Flange ring FTC4609 as the old one was damaged.

I was servicing the gearbox yesterday, when i hit a snag It appears the new filter has damaged the bag and somehow had water in it. So i need to wait until Tuesday for a new one.



Plus, i'll pick up some new engine mounts at the same time.

Scoobs

I doubt there's any damage to the filter... Methylated spirits is an excellent drying agent for this sort of situation...Put the filter in a shallow platic container and pour metho (about 100ml) into the filter inlet and give it a good rinse. Let it drain, dispose of the metho in the plastic container and then repeat using fresh metho. Dry the filter either in the air or give it a good shake to get rid of residual liquid and put it in the kitchen oven @ 60 degC (fan forced setting) for 10 mins. Job done If there's a lady in the house and she objects to your conscripting the oven, then borrow "her" hair dryer... works just as well.

concur, the mesh is stainless, if there's no obvious sign of rust on the casing Id go the clean and dry then use it.

however as its the only internal protection is the filter always err to the side of caution

The engine is in... But...

So i've got the motor in. Am about to do up the Bellhousing bolts, but just thought i'd check the alignment of the TC to Flex plate. While it all looks good, as i pull the TC forward towards the flex plate, it likes to pull back about 3-4mm once i release the pressure. I thought it should just sit there. Matters are not helps by the Alloy sump, which means i cant see much.

It all lined up perfectly on the bench.

Any thoughts?

Originally Posted by 81stubee

The engine is in... But...

So i've got the motor in. Am about to do up the Bellhousing bolts, but just thought i'd check the alignment of the TC to Flex plate. While it all looks good, as i pull the TC forward towards the flex plate, it likes to pull back about 3-4mm once i release the pressure. I thought it should just sit there. Matters are not helps by the Alloy sump, which means i cant see much.

It all lined up perfectly on the bench.

Any thoughts?

G`day ,

i pressume the TC has no oil so a lack of weight and it possibly just means the seal should work .

With what you`ve had done i don`t think it has any option but to be aligned .

Originally Posted by 81stubee

The engine is in... But...

So i've got the motor in. Am about to do up the Bellhousing bolts, but just thought i'd check the alignment of the TC to Flex plate. While it all looks good, as i pull the TC forward towards the flex plate, it likes to pull back about 3-4mm once i release the pressure. I thought it should just sit there. Matters are not helps by the Alloy sump, which means i cant see much.

It all lined up perfectly on the bench.

Any thoughts?

IT might just be springing back against the new pump seals, 3-4mm is a bit excessive, it might be getting a bit of helping hand from the spigot bushing if its oiled and sealing up tightly enough to be making an air spring.