Series 3 Engine rebuild

[normbourne]

Ihave just pulled my engine down, and there is a ridge at the top of the cylinders.
There appears to be about. O.05 inches diff between the worn and unworn diameters.
At what point should consider a rebore...?

I,m wondering if a hone and new rings should do the trick...??

Any advice lads..?

Tanks & regards,

Norm.

[drifter]

I went the rebore route (I had a lip, too) and ended up going from factory original to 40 thou over.

[VK3UTE]

G'day Norm.

If you have come this far you might as well go for the rebore, it's not a very expensive exercise and she will last for another 30 years.

[Homestar]

Although a rebore may be the way to go, you may get away with it if you are on a tight budget. I would check to see if the bores are worn further down, as it may have only worn the top of the bores. When we didn't have the $$$ for a rebore, we would cut the lip off the top of the bore, give it a good hone, then check the ring gaps before reassembly with the old pistons. We found that in some instances, we could use oversize rings with just a file of the ring ends to make sure minimum clearances are maintained all the way down the bore.

This is a bit dodgey mind you, and it will rattle like a bitch when cold, but we have done this to a few vehicles many moons ago when required and they have run ok, and lasted fine. By the way - none were Landy engines, but the theory is the same. We did this to some Holden 202's, a pre crossflow ford engine, and some Jap stuff - all were fine.

If you have the cash, go the rebore.

[normbourne]

Hi Guys,
Many thanks, I have just revisited the measurements and have revised them as follows:
The ridge at the top of the cylinders, doesnt appear to be as bad as at first thought...!
There now appears to be about. O.008
inches diff between the worn and unworn diameters.
These measurements were taken on No.4 cylinder, fore and aft.
Actual measurements, unworn from the manual, 3.562, and worn 3.570.
The worn measurements were taken, at the top of the cylinder, just below the ridge.
Upon reflection does this now make ridge removal, and new standard rings a possibility...?

[Homestar]

Sounds like you could get away with that. What is the ring gap supposed to be on these engines? - I don't have the specs.

[normbourne]

Hi lads, sorry about delay i got myself into a bit of trouble with a couple Of heart attacks.

Anyway because the ozzy dollar is so high, It proved to be economical to import a short engine from the UK. Great gear presently building with bits off the old engine, Albeit slowly slowly.

I am now investigating hall effect conversion of the distributor, using the the hkz 101 Sensor,
Which are readily available. The prob is the rotating vane.

Any ideas guys.?

Norm.

[normbourne]

I was about to put the head on when I noticed that the fit of the head gasket was such that there was a substantial space between the cylinder edge and the edge of the gasket on the right hand side.

I spoke to the supplier and he assured me it was ok, but I am of the opinion that a void will be created, between the cylinder and the cylinder heard, and carbon will soon form and become a problem during combustion, eg. Pre-ignition etc.

What do you guys think..?

[Ozdunc]

Seems like the gaskets are like this

Photo of banjos engine rebuild

I'm not too clued up on the dynamics of combustion, but wouldn't carbon only form if the air/fuel ratio was too rich rather than due to the shape of the combustion chamber?

[ian4002000]

May I suggest putting Hylomar on the head gasket both sides. It will assist sealing and is easily removeable when required.