help needed with shortblock, crank seems tight

[1funbug]

I've lurked for a while here. Now I need some advice. I'm assembling a type 4 camper special kit purchased second hand. I've been meticulous about the crankshaft an camshaft assembly and install. I triple checked the crankshaft bearing placement and used scribemarks on the outside of the bearings. The case halves are assembled and torqued. Distributor is installed and indexed. The crank is not as easy to turn as I have read in several online posts. It turns smoothly when I manipulate two of the connecting rods. It just doesn't "spin freely". I need advice from seasoned engine builders here.

Am I worrying about nothing?
Should I separate the case? What would I look for?

Thanks!
Matt

[Amskeptic]

Matt,
We are in a dangerous spot here, due to the imprecision of words.
Raby engines generally are top-drawer and they will punish you mightily if you do not know what "clean" means. If Jake has set the bearing clearances at .0025" or so, the merest dirt can become a problem. The last Raby rods I assembled for poptoptom came in at a racing engine's .0008" (that is eight/ten-thousandths of an inch). His prior builder had dirt in there, and they were locked up solid.

Ask yourself, how clean was it really?

Next issue is assembly lube. Some have moly grease (not good) Lubriplate (not good) TRW high zinc (fine) or engine oil (best) on the main bearings. Grease can load down the spin test.

It sounds like you have the rods assembled. Do they fall slowly, moderately, or bangdadangdang? If you are rotating a crankshaft with rods all bolted up, there is some additional drag you have to take into account. (hopefully rods are falling slowly but smoothly)

Is the flywheel on? If no, you must rotate in operating direction to get crankshaft to spool out towards the crank-to-mainbearing contact area. If it is on, what is the end play?

Subjectively, the most important sensation you need to have when rotating the crankshaft is smoothness. Check for any variations in effort. If you have them, take apart and look for any scoring in the bearings from dirt. Scrape bearings with a brand new razor blade if you see a little shiny stripe with a chunk at the end. Wipe crankshaft clean with a lint-free cloth. When reassembling the case, no dirt no dirt.
Colin

[1funbug]

Matt,
We are in a dangerous spot here, due to the imprecision of words.
Raby engines generally are top-drawer and they will punish you mightily if you do not know what "clean" means. If Jake has set the bearing clearances at .0025" or so, the merest dirt can become a problem. The last Raby rods I assembled for poptoptom came in at a racing engine's .0008" (that is eight/ten-thousandths of an inch). His prior builder had dirt in there, and they were locked up solid.

Ask yourself, how clean was it really?

Next issue is assembly lube. Some have moly grease (not good) Lubriplate (not good) TRW high zinc (fine) or engine oil (best) on the main bearings. Grease can load down the spin test.

It sounds like you have the rods assembled. Do they fall slowly, moderately, or bangdadangdang? If you are rotating a crankshaft with rods all bolted up, there is some additional drag you have to take into account.

Is the flywheel on? If so, check endplay. What is it?
Colin

Bearings were cleaned with carb cleaner, wiped with lint free towels and lubed with 30wt. brad penn break-in oil.
I would say the rods fall between moderately to bangdadangdang.
Flywheel is not on yet.
The case itself was washed and scrubbed by hand twice by me. Galleys were bore brushed and inspected by flashlight ( with optic fiber wand attachment).
Previous owner also paid for prep work. I don’t know exactly what that en-tales.
Matt

[hambone]

How hard is it to turn? It will be gummy because of assembly lube, and even moreso with a tight tolerance engine. But you don't want any constipated binding I'm thinking...
I used fancy German moly-based assembly lube in a blue tube, really thin weird stuff. Moly and melted butter had a baby.

[1funbug]

I used 30wt. oil for assembly. I would definitely say that it is not "binding"..

[Amskeptic]

I used 30wt. oil for assembly. I would definitely say that it is not "binding"..

If there are no variations in rotational torque, then you have the information you need to make an executive decision.

I would plastigage one rod, let us know the clearance. Some people think you can fall sloppily between the limits of factory specifications. I say, set it up at the small end of the specification window and enjoy a couple extra tens of thousands of miles. Amateur rods should be right near .002", if you are on top of your game, shoot for .001" to .0015" with that slick oily slow drop test.
Colin