As a final check, take magnifying gl*** and check the cross hatches or machining marks where the cap meets the rod. Since they are finished as one piece those marks will (should) only line up when the correct cap and rod (or main) are together.
It is perfectly normal and expected to get to be harder to turn as you add pistons, each is a little more friction, as Jim said it takes a few to get the feel for it. If it doesn’t turn now, back up and loosen one bearing cap at a time until it does start to turn, that will tell you where the problem is. There was a question about resizing rods, it entails removing material from the parting lines then honing them round again, restoring their size. Most times unless a bearing has spun it’s not necessary for an average engine. Sent from my iPhone using H.A.M.B.
If main caps were not stamped they can be matched to their appropriate webs by matching machine marks on their sides also.
Were the pistons fitted to the new bores? That last honing is critical for correct piston-cylinder wall clearance. I was taught to fit pistons (upside down in the bores) and use a feeler gauge with a tension scale attached to it. Does anyone do that these days? Now when I have a block bored, I have my new pistons shipped to them and let them ***emble the short block. Money well spent.
Hahaha it’s true, I think because it’s been a few months and I didn’t write anything down, I’m going to start taking it apart so will use these opinions as I go. My 327 just used a key on the harmonic balancer and you just drive it on with a hammer and piece of wood as an interference fit. But someone suggested I cut a thread if I need to take it apart.
What was suggested was to take it to a (qualified) machine shop and have them drill and tap the snout of the crank. Unless you come up with a pretty ingenious and accurate drill jig you'll get a crooked hole.
Ok so I loosened the first two rod caps just a bit and now it turns, so I have a torque spec on turning it, it takes 50ft lbs to start turning then turns at around 30-35
I plastigauged those two rod bearings again and they are at less than .0015 but over .001 See this is what I thought, it’s very tight. Another thing that was suggested is that if it’s just tight my stock starter cannot turn it over since it’s fairly high compression, 10:1 or so I should use a high performance starter and it will be fine. What do you guys think?
But that doesn’t mean anything if you loosened two rods....as I said before with it torqued loosen one at a time until it turns....that seems like a lot of torque to turn it. How did you measure it? Sent from my iPhone using H.A.M.B.
My SBC is close to 10:1 and a stock GM hi-torque starter spins it fine. I would continue taking all the pistons out, keep the bearings with the rods. You'll need to take a close look at those and the crank before doing anything else.
From what I read crank turned Ok until rods and pistons were put in so that most likely rules out the mains. Were the rods installed in the pistons right? If the chamfer at the rod journal is not against the crank things will get tight check side clearance on the rods. If none of the piston were hard to install that's where I'd look. I didn't see the pictures with the pan off. By all means check side clearance to see if rod will move.
Maybe I missed something but you said the crank was turned but you did not resize the rods and you plastigauged it and it looked ok (.002) then you plastiguaged a couple rods (post first ***embly) and find .001-.0015, what's the story on the rods as they look like new aftermarket as well as the rod bolts, something does not add up.
I bought the bearings at .002 as was told to by the shop that turned the crank, the rods are new aftermarket (Eagle) and all the bolts are new. I have not checked the other rods yet but suspect they will all be about the same .001-.0015 is that too tight? i guess not if it moves properly.
right because two rods are loose who cares about the torque but if its that high without two rods clamped its only going to get tighter. if I buy new rod bearings the next size up is .005 so would probably sit at .0045 or just under. or just buy another set of 002 and try different sets to find a looser fit.
If the rods won't move back and forth on the crank throw ...somethings wrong. EZ to get them backwards..
I realize that the use of plastiguage was/is an (acceptable) method for years but I am a firm believer in a statement by Albert Einstein......“The definition of insanity is doing the same thing over and over again, but expecting different results”. If your machinist can turn a crankshaft then he will have the micrometers to measure your parts much more accurately than the processes you have used up to this point.
This didn't stopped me from going back to the frig 10 times looking for something. Same stuff I didn't want to begin with each time.
1.5 thou is on the tight end but not unacceptable, is there something behind a bearing shell? As I’ve said twice now loosen one thing at a time until you find what’s making it tight. Did you set end play on the crank to seat the thrust bearing? There are lots that can cause it tone tight Sent from my iPhone using H.A.M.B.
In the pics above, especially the one close up of two rods, the lower rod looks backwards, but might just be Parallax error It does sound like the insert is crushing on the radius
one thing I haven't seen mentioned is the piston/wrist pin fit.press on or floating?most new pistons are too tight a fit for the pins and need honing.some shops just press them on and send them out the door
Just a suggestion , you should never install a dampener in this manner. Use a installer tool, your crank will thank you.
I n order to do what I suggested you need the crank snout machined for a bolt. That should also be done IMHO.
I discovered my starter was not turning, it was clicking and engaging but not actually turning the ring gear... Wow
What do you do with the 015 of side to side play on the rod bearings? do you split it or do you force them apart? I never did see anything about that in my research or book.
The Jalopy Journal
