Rebuilding and Blueprinting a Vintage Engine

Thanks for taking the time to post your text and pictures. I rebuilt the engine in my '66 Bonneville about 1985 and you're bringing back a lot of memories; It's still going strong, although I don't ride it as much as I used to.

Bob

Can you provide a little detail on what you use to polish the pistons?

Thanks,
Craig

As you are polishing engine parts, could you shed some light on this: I was always told by the so called "experts" that you should polish rods in the same direction, always. Is this true or it really doesn't matter as long as the end result is smooth and uniform?

Thanks for your trouble posting all this info.

beautiful work. ignore the retards, they'll always come in and criticize...it's a lot easier to pick apart someone elses work than to actually do the work yourself.... and your postings remind me how badly i need a better surface plate..

Let me get this out of the way first, I am immensely enjoying your thread and the precision work you are doing. Thank you for taking the time to post.

Your comments are understood, but surely you anticipated some discussion and input from other " those that can do"'s.

With no intention of high jacking but to differentiate myself from the " those that can't " here's photos of a couple of swing arms for a Husky 400 XCE that I modified for the later model rear brake, had weld repaired, and then shot peened. This is NOT to say my humble efforts in any way compare with your talent.

New brake reaction lugs added to older swing arm to use newer brake


After shot peen. The arm rings like a tuning fork after shot peen.

I always herd the same thing. Finish with longitudinal polish marks.

Dewey, keep it up and ignore the noise. I'm interested in your project and your photos.

Please, go away.

It's refreshing to see that someone using the too often misapplied term of "blueprinting" an engine is actually doing just that.

I haven't built any engines in over 20 years, but spent several years of my former career as an automotive mechanic working in a machine shop building engines. We seldom did anything aside from the mundane daily runners, so it was always good when we could apply some higher level skills to a project. I fully understand your excitement at being given a long leash on this project.

Yup, he's a twat too. I couldn't be less envious of 2 people like you and him in the entire world.

If all you're going to do is come in here and criticize, why do you bother ?

He's not posting so someone can post some 'constructive criticism'. He knows what he's doing, he doesn't need your advice.

Again, please just go away and leave this thread to those that enjoy it.

I'm done with you.

To the OP - my apologies, I just hate people shitting in great threads like this. I'm done responding to him.

What checks did you use on the parts for this engine? And why no mention of fitting hardened seats?

The assholes in this thread are going to scare away the op who is posting some fantastic stuff. Shut the fuck up and just listen, you learn a lot more that way.

Eagerly waiting for more pics.

I love this thread...Well, most of it.

Couple questions for the OP...just out of curiousity.

First, when you're measuring the volume above the pistons (after hand finishing the domes), how do you know they're at exactly the same height relative to one another? I'm guessing one would have to put a wrist pin in the piston and support it from below (the known surface plate) with a 123 block or something similar?

Second, were those nicks in the con rods typical? They look pretty significant to just be tool marks, but for all I know they all looked like that back then! I have done a few very basic rebuilds, on much newer engines, but I don't recall the rods having nicks and gouges like these did.

Please don't stop posting pictures...I'm learning interesting new stuff!

When in the engine assembly.

sorry..I don't understand your reply.

Forgive me if you already see what I was driving at...but in case you did not, I was referring to the pictures above when he was filling the area above the pistons with measured amounts of liquid to determine the differences in volume above the piston domes. Since he's measuring fractions of milliliters, It's critical that the piston be located accurately and identically for each. But there are few places on the piston itself he can use to control how high it's being held! He's altered the domes of the pistons, so they're no longer identical, which means he can't use a simple measurement from the top of the cylinder! The bottom of the piston skirts are likely not accurate enough for this purpose either, so he can't just let the skirt rest against the surface plate. And since the volume above the piston, in the completed engine, is ultimately controlled by the wrist pin anyway, it seems logical that this is the feature he'd use to locate the pistons prior to taking this measurement.

I'm just trying to get his method straight in my head, and then file it away in my memory bank for future reference!

I would guess with a dial indicator off the deck measure to the top of the dome? Or maybe a degree wheel to accurately measure tdc?

Do you do any measurement of squish clearence and area, in relation to matching the volumes? In my understanding of combustion engines volume=cr but squish area and clearence also has a substantial impact on combustion.

It's true that he's trying to verify that when the piston is at TDC, the volume above each is identical. But since the piston and cylinder are on a surface plate, and not connected to the crankshaft, how does he know if the piston is at TDC? Like I said...he's polished the tops of the pistons...so you can no longer assume that the top of one is identical to other anymore. For that matter, who's to say they were identical to begin with? Point is, it would seem to me that you can't measure down to the piston from the top of the cylinder.

I say that like it's fact...but really, you might be right! The tops of the pistons might be close enough to identical for the purpose of this test. That's why I'm asking...just to learn something.

Hey OP-

I don't know enough about this kind of stuff to know what I don't know- but I like it & I appreciate you posting this up.

Please don't get sidetracked by the commentary.

Put a few of these dipshits on ignore and let's roll!

I love stuff like this. I wish I was more confident when it comes to internals.

Hate to admit my entire knowledge base for what you were doing comes from the show horsepower

Great work, it appears you walk the talk.