68 327 Piston and ring question

[Happy_dan]

Update and a question. I think I know the answer.

I have been searching for the maximum I can hone the cylinders before it's too much.

Cylinder number 2 had a couple of pretty heft scratches in the bore so I have been honing that one to see how far it goes. So far I am at 4.0035 to 4.0040 and I think I have another 2 or 3 thousands to get that scratch out. I think I will end up at 4.0070 to 4.0090. Is that too much to simply re ring the pistons. All other parts of the pistons are ok. I checked the ring grooves and the skirts etc. But that is all mute if I have to go .30 over and I will get new pistons of course.

Can I use the same rods if I do that or do I need to get new rods as well?

I gave the college try to save what I had, but it looks like I need to go .30 over. But before I do that, would love your opinions.

[incoma]

7-9 thousands will definitely be too large for a stock ring/piston. You’ll have lots of blow by. You’ll need to bore it out. Rods won’t change, just need new pistons.

[Happy_dan]

Thank you, that is what I thought but hoped not.

Good opportunity to have machine shop go over the whole block and get new pistons mounted on existing rods.

I guess it's best to do all this now anyway. Appreciate the responses as always!
I am getting old so I was trying to do this properly but not the full boat. I'll just drive it more to get my value. LOL.

[Happy_dan]

Just a quick update. I decided to go for the .30 over and new pistons.
Heads came back today, milled, magnafluxed, valve job and new seats.
Crank is done, grinding of main and rod journals.

Block goes next week for boring and cleanup then I can put it back together! Thanks for all the advice. I was listening!

[57taskforce]

Nice! Was your crank grooved pretty good? I’ve done a lot of them with only polishing the crank.

I actually dropped the crank back into the vortec 350 I’m building today. Waiting on rod bearings from jegs. I’ll be ready to stab the used pistons/rods and new rings once I get the rod bearings.

[Happy_dan]

It had some pretty deep scores. They ground them .010.

I could easily catch a fingernail in the grooves in one of them

[Happy_dan]

Just a quick update, hopefully more soon. I got the block back. It's now .30 over and I measured the bores and they are right on except one that is .029 so no issues there.

I chased all threads on the block.
Started to put back brackets and other parts while I am waiting for the crankshaft to come back. The shop sent it back to machine shop by accident. Hopefully here tonight (3/18/21).

I cleaned it all really good, blew everything out and put a light coat of WD 40 to prevent rust.

I installed the bottom half of the main bearings to be ready to measure clearance when I get crank back. I'll install crank, caps and measure gap looking for 002 to 003.

Then I will take crank back out, clean again and lube all bearings and install crankshaft for good. Hopefully I will have that done in the next few days. Then it's on to the rest.

I have all new cam bearings, main and rod bearings, pistons, cam, lifters, oil pump, water pump, fuel pump, timing set and I am sure other new parts I am forgetting.

[Happy_dan]

Just an update in case anyone cares.
I have the crankshaft, pistons, cam and timing set all installed.

Just a note to anyone that is a rookie at this. Listen to the experts here. Measure everything. I had to sand down the thrust bearing to gain a .002 more clearance. I only had between .002 and .003 and I could not even move the crank. Now I have .005.

Also had to grind a few piston rings that were too tight. Less than .014 and I wanted them all to be .017 for my application.

Heads are next.

[pjmoreland]

Looks like a fun project!

[Happy_dan]

Thanks, I truly am enjoying it! I am lucky to have several friends that can help guide me. It is really not that hard, just a lot of details and they are very important.

I wish I could have had the time and money to do more of this when I was younger. But now that I have the opportunity, I am thoroughly enjoying my first engine refresh!

[mr.mud1]

Originally Posted by Happy_dan

Thanks, I truly am enjoying it! I am lucky to have several friends that can help guide me. It is really not that hard, just a lot of details and they are very important.

I wish I could have had the time and money to do more of this when I was younger. But now that I have the opportunity, I am thoroughly enjoying my first engine refresh!

hi Dan,i told you,you could do it,all the faith in the world in your abilities.i'll be looking forward to the update when it actually lives.that's always a god day.

[Happy_dan]

Originally Posted by mr.mud1

hi Dan,i told you,you could do it,all the faith in the world in your abilities.i'll be looking forward to the update when it actually lives.that's always a god day.

And you sir, are on of the ones that helped me and continues to help me for which I am very thankful. Now to get your truck home!

[Carl Spangler]

Originally Posted by Happy_dan

Thanks, I truly am enjoying it! I am lucky to have several friends that can help guide me. It is really not that hard, just a lot of details and they are very important.

I wish I could have had the time and money to do more of this when I was younger. But now that I have the opportunity, I am thoroughly enjoying my first engine refresh!

Congrats on the progress.................. But we need (more) pics or it didn't happen!

[Happy_dan]

LOL, I will post more pictures soon. Really not a lot to see.

[mr.mud1]

Originally Posted by Happy_dan

And you sir, are on of the ones that helped me and continues to help me for which I am very thankful. Now to get your truck home!

thank you sir.it is my pleasure to lend a hand if i can.i'm working on getting my truck home,it takes more time out the day than it should but i'm happy to report although not wanting to get my hopes up,i'm hoping it'll be on a car carrier heading east late this week or early next.an update will follow if i have any news.take care.Greg

[Happy_dan]

[Carl Spangler]

[Ol Blue K20]

It's looking a lot like a engine now! You'll be so proud when it fires up.....

[BigBird05]

I'm a little late to the party, but did you tape out all of the bolt holes in the block and the heads?

[Happy_dan]

Originally Posted by BigBird05

I'm a little late to the party, but did you tape out all of the bolt holes in the block and the heads?

I used a thread chaser to chase all holes in the block and in fact all holes anywhere before putting bolts in.

[garyd1961]

I just did this with my Toyota pickup. I gave $400 for the truck and didn't want to put a lot of money in it. New rings, bearings, timing chain set, cleaned all the carbon out the head, lapped the valves, put all new gaskets and seals in it. I did use all factory parts though, no cheap stuff. I have about 3000 on it now and it runs great. Oh, almost forgot I did put a new oil pump and water pump in it also.

[Happy_dan]

Ready to go back in the truck. Maybe of the weather cooperates, I'll paint the transmission but I really want to get it back on the road so I am not really worried about that.

Finishes up installing exhaust manifolds, flex plate, transmission last night. Changed the transmission filter and gasket and just need to remember to refill transmission when installed.

[Ol Blue K20]

It looks good

[Happy_dan]

Back in the truck. Just need to button up all the details and break in the cam, change the oil and go for a ride (I hope. )

One crazy thing I am fighting with is the spring clip that holds the accelerator rod on the gas pedal bar. Any hints on that? It's hard to get the round trunion thingy through the hole in the spring clip and the rod.

[mr.mud1]

Originally Posted by Happy_dan

Back in the truck. Just need to button up all the details and break in the cam, change the oil and go for a ride (I hope. )

One crazy thing I am fighting with is the spring clip that holds the accelerator rod on the gas pedal bar. Any hints on that? It's hard to get the round trunion thingy through the hole in the spring clip and the rod.

hi Dan,looks great.i just sent you a couple pictures from my 67 wagon, of the style clip i think you may be struggling with,if i'm wrong,send a pic of what you have there and we'll figure it out.Greg