My Fourth Engine Build

[ruckman101]

A hole a tad smaller than a quarter in the top of piston number three said to me a complete rebuild, not an oil drain and a replacement used piston. Of course, it is an option if that's what the budget dictates. Fortunately, I get to do a fresh build.

I went hog wild with possibilities and eventually settled down and decided on a stock single port engine but with a dog-house shroud and oil cooler. With what I had. A green light to excess just didn't seem prudent. Plus, to veer from stock seemed such a betrayal to the notion of the original intent. So I went all out with the shroud aberration.

So I got out the "engine kit" I had picked up from Bookwus some years back. No heads or cylinders, but a case already align bored and machined. The crankshaft was tagged for a machine shop but hadn't been there yet. Flywheel looked freshly machined, and all the bits and pieces.

Last time I had machine work done was a decade ago at the no more Dan Hall's. Finally found a couple, but the cost of them reconditioning my crankshaft and connecting rods was more than taking my cores in for reconditioned already. So I did and hustled all the parts to the machine shop for a spin balance on the crankshaft drive components as a unit.

Time to clean up the case. Funny how you don't see things you never thought to look for.



Bent case studs. Sigh.



And no locktite. Considering a different case. 10 mm head studs on this one. Would prefer the 8 mm.

I don't seem to be getting any quicker on building a new engine, getting more particular seems to be slowing me down. I don't recall addressing any of the concerns I have now with any of the past builds.


neal

[Amskeptic]

I don't recall addressing any of the concerns I have now with any of the past builds.
neal

Thank goodness for that . . .

Consciousness does that. Slows you down. Makes you consider all of the miracle more closely.
Enjoy. Take your time. Dot all headli, I mean "i"s, and cross all "t"s.

In our new distracted world of diffident machinists and crap parts, you have to Will these Very Thoroughly Cleaned parts into alignment and teach them to play with each other nicely.

You especially, focus, slow down, break it down into discrete operations, double check, if your mind starts to buzz with inner thoughts and dialogues go write them down until your mind is blank. If you get stupid and distracted or tired in the early evening, maybe working on the engine in the early morning is the better time for you.

At all times, ponder the actual working of these parts as you assemble them. It is an amazing concert of controlled violence.
Colin

[tristessa]

Keep the case, and have case savers installed for 8MM studs.

[Maz804]

Been waitin' on this thread... Actually, just wantin' to be readin' more of your writin'. And this is always a learning experience for all, 'specially me.
Hal seems to have a good idea on "savin' that case."

[ruckman101]

Thanks for the writing compliment Maz804.

Anywhoo. Apparently there are issues with swapping case savers. Savers with the same outer dimension as the current that accepts the 10 mm studs apparently aren't made thicker walled to take an 8 mm stud.

So the thought was to get a different case align bored. Both Gretchen's and Ramona's would bore the same as Bookwus's at .040 over, and my bearings would still work, and one of them had 8 mm studs, which turned out to be Ramona's. But ... .



A stripped out stud that would need to be addressed. And it's a Mexican case whereas Bookwus's is original German. So it looks like I am back to the Bookwus case with 10 mm studs.

Now it has been sitting on the shelf for a few years, and the bearing seating surfaces are certainly not "fresh from the machine shop shiny". Should I be concerned? Hit them with some uber fine grit sandpaper?



I missed my little Lumix cam. We lost the battery charger but have a new one. The iPhoney thing wasn't cutting it. So here's a shot of a chunk of piston I found when I split the case.



And a shot of recently cleaned up used hardware.



Vid obligations tomorrow, so looks like I am ready to start this build Wednesday. Heads are still in the shop, but hopefully there aren't any other issues to hang me up. Slow though, going to actually pay attention to the appropriate spec for the distributor drive. Whooda thunk? And then on another new front, getting the #3 bearing and gears onto the crankshaft.


neal

[Amskeptic]

Savers with the same outer dimension as the current that accepts the 10 mm studs apparently aren't made thicker walled to take an 8 mm stud.

the Bookwus case with 10 mm studs bearing seating surfaces are certainly not "fresh from the machine shop shiny". Should I be concerned? Hit them with some uber fine grit sandpaper?

A) Can you stick in a heli-coil that would allow the 10mm case savers to accept 8mm studs. Steel to steel should be seriously strong enough. Most helicoils are driven into stripped aluminum, while these would be supported by the case saver steel threads on the outside, and the 8mm steel stud on the inside.

B) NO SANDPAPER inside an engine. Please! Please give this engine a chance for a long happy life. Sandpaper grit is hideous for an engine that doesn't have a fricken oil filter. Sandpaper grit in the oil galleries is deadly. Even a machine shop wash cannot guarantee that you will get grit out of gallery dead-ends.

Try washing the case halves with dish detergent and a nylon scrubby brush. Rinse and dry. Inspect. Next step would be scraping the bearing saddles with a fresh razor blade. Be smooth consistent. Look for any nicks or projections on the parting surfaces, front seal bore, cylinder spigots, and razor them down. Then last step is to send off to the machine shop for a cold tank serious wash. Then you use carb spray and a lint free paper towel for last clean during actual assembly steps.

Here's some bearing saddle cleaning for ya, the 2008 jblair630 4-oversize razor blade align-bore in a driveway. Still running down there in Austin:

[hambone]

Neal you should take a look at my old build thread, I went thru a lot of this already and it may provide you with some EZ answers.

[ruckman101]

Helicoils. Now that's a thought. And thanks Bob, I will.


neal

[ruckman101]

Eh, going with the 10 mm studs. So chased threads on them today and pondered the issue of which oil relief valve spring to use.



Is it a single port case or a dual port case. AE and the case oil galleys suggest it's a dual port case. Not sure, I see no AE on the case, but everything in the kit was labeled as such. So I'm leaning to the longer spring and higher pressure relief, now that I've mixed up the two springs and no longer know which one was labeled AE that came with the kit.

Then there is the difference in the two plugs.



I'm going with the longer springs on the plug with the higher profile spring centering post, as the wire of the longer spring is fatter than the wire of the shorter spring for the pressure control valve.

Used a tap and die set to chase the threads on the 10 mm studs. Before.



And after.



Chasing the nuts, too. (badda boom)


neal

[ruckman101]

Already reconsidering the longer spring choice. Trying to wrap my head around function and ramifications of a weaker or stronger spring. If I have the concept grasped, when oil is thick and cold viscosity is high so with enough pressure, this valve opens and diverts oil from the cooler back to sump until it warms and the pressure drops and oil then runs through the cooler.

A kind to things way to work a smaller quantity of the available oil supply to operating temps for the engine parts that want it the quickest.

So the stiffer the spring, the quicker it would close and begin running all of the oil through the cooler. The laxer spring would keep oil from the cooler longer, closing perhaps slower with a less abrupt transition.


neal

[ruckman101]

Or do I have that completely backwards. And what would the advantages be to the applications of the two differing systems?


neal

[hambone]

Don't remember offhand. What does Wilson say on the subject?

[ruckman101]

Wilson explains but doesn't mention the two different springs. Hot arid desert environments v temperate colder?


neal

[Amskeptic]

Wilson explains but doesn't mention the two different springs. Hot arid desert environments v temperate colder?


neal

Don't over-think this.
A stiffer relief valve spring means the oil is diverted away from the cooler for a shorter time and subjects the cooler to higher pressures.
A too-long relief spring (too many coils) means it cannot dump the excess oil into the sump.

The control valve spring at the front of the case DOES affect overall pressure, but it does NOT help a damn thing as far as low oil pressure issues.
Colin

[ruckman101]

Sounds like I'll be using the shorter spring. I think I'm going to get to things today. Proper play for the distributor drive. One more high pressure water rinse for the case, followed by compressed air dry, carb spray, paper towels at hand. Got the bent studs replaced. Although I found the long stud on the oil screen plate that the oil pick up is held down by was also bent, so that, plus the oil pick up assembly itself still needs to go on. If it's loose, peening the case metal is suggested. Somehow I'm hesitant to peen, and want to use red thread lock instead. Figured out the cam/oil pump combo. Dished cam, 26 mm oil pump.

Nervous, like making the first cut into a sheet of plywood for some project.


neal