Engine Rebuild Suggestions

[Pir0San]

My block is in need of a rebuild. My piston rings are bad, which is burning oil inside of the combustion chamber, making the car like a rolling smoke bomb upon acceleration. I know it's nothing related to the valves, because the head is fully rebuilt with new seats, seals, everything. So, I figure that while I'm changing the piston rings, I might as well get new rod and main crankshaft bearings, get the crank micropolished if it needs it, and get a new rear crankshaft oil seal.

I looked into Victoria British for my rebuild needs, and their prices are as follows:

1. Piston Ring Set: $39.95

2. Main Bearing Set: $49.95

3. Rod Bearing Set: $29.95

4. Rear Crankshaft Seal: $8.95

So, what kind of quality can I expect from the rings and bearings from VB? Are one type of ring better than the other for a mostly stock setup? Will I need to hone my cylinders, and how can I tell if I need to? How can I also tell if the crankshaft needs to be micropolished?

[Pir0San]

I did some more research into cost of engine rebuild parts from Autozone and Kragen's, and so far, I've come out with these prices:

1. Premium Ring Set (Chrome top ring): $66.99 (A/E Clevite, Kragen's)

-or-

2. Regular Ring Set (Cast Iron top ring) $40.99 (Beck/Arnley, Kragen's)

3. Main Bearing Set: $30.59 (A/E Clevite, Autozone)

4. Rod Bearing Set: $32.94 (Autozone)

My total with tax for the premium rings and other bearings would be $140.63, and the price for the regular rings and other bearings would be $112.62.

I did some research into the difference between Chrome top ring and Cast Iron top ring, and this site came up http://www.hastingsmfg.com/Service%20Tips/ring_set_composition_recommendat.htm. They state that cast iron rings are good for an every day engine, but chrome rings are good for enviroments where the engine may be driven hard, or dusty enviroments and that of the like. I'd like to be able to take my car down to the track and not have to worry about hurting the engine, so would chrome be a better way to go?

[Arne]

Before you buy your parts, you need to measure the wear on the bores and pistons, if you haven't already. If the cylinder bores have more than .005" taper, or have a good sized ridge worn at the top, you should have it bored oversize and replace the pistons as well.

I've been in this situation before, and would never buy the parts ahead of time. That's a sure recipe for getting the wrong parts.

[Pir0San]

how would I measure the wear on the bores and pistons? I have a feeler gauge, but I'm just unsure as to how to inspect the block for wear.

[Arne]

A good service manual will tell you, but the basics for block wear are to measure the bore with an internal micrometer. More important is to measure the bore size at both top and bottom and compare the two. The difference is called taper, and the amount of taper that is allowed should also be in the manual. The bores also wear more from side to side, and less front to rear. So measuring how oval the bore is can be important as well.

Pistons wear on their skirts primarily, although the ring grooves can wear as well. Piston pins can wear too.

But to do these checks you have to wait and tear down the engine first. Considering that you know you are getting oil past the rings, at this point I'd recommend pulling the engine, and then completely disassemble it to measure for wear. The chances that new rings and bearings alone will fix it aren't all that good. Time for a good service manual, and maybe a reference book on rebuilding an L-series engine.

[Pir0San]

man, this sucks, my Z is going to be down again...

I have another block, with pistons, but the block has a bad rod and crankshaft (I spun a rod bearing due to water leaking into the oil. In the worst case scenario, if my block I have in there now is damaged badly, could I take the rods off of the pistons for the block in the car and put them on the pistons from the block with the spun crankshaft, and replace the crankshaft from the one in the car?

I'll have to take everything apart, load it all into the truck, and take it down to the machine shop for investigation.