s25hanh

iTrader: (8)

I am stuck and so is my crankshaft. I have a 5.3 im building - cleaned and honed block, new cam bearings (installed by machine shop), new main and rod bearings (std size). Im re using the stock rods, pistons, and crank (all refreshed from machine shop).

Long story short- I was torqueing down the rod bearings and after final conclusion, if the #1 or #7 rod is torqued down the crank will not spin at all. Do I need undersize bearings? I took off the bearings multiple times and made sure it had plenty of assembly lube. Also when i took off the #7 rod bearing the upper had a pretty decent scratch out of nowhere?

mark21742

Are you sure rods 1 and 7 aren't in backwards?

Quick Ranger

iTrader: (2)

Did you check the bearing clearances?

crainholio

iTrader: (2)

As QuickRanger asked...what clearances did you get when you measured the mains & rods?

s25hanh

iTrader: (8)

"Flat forward", they are definitely installed correct
You're talking about plati gauge right?

crainholio

iTrader: (2)

Plasti-Gage is better than nothing at all, but I don't build engines with it. Snap gauge and micrometer here.

Again...what clearances did you measure?

s25hanh

iTrader: (8)

Sorry man, I go out of town and I'm only able to work on the car during the weekends. I am so confused, I didn't put the bearings in awkwardly, they went in straight but yet my plasti gauge came out crooked every time. I even switched the two pistons I was having problems with (#1, #7). So I was thinking that the crank came out wrong after polishing, as if the #1 spot on the crank is warped. I did not even try to plasti gauge the #7 spot on the crank yet. At this point I just wish that I just straight swapped the 5.3 bottom end without taking it apart




I got .0015- .003

be good

that doesnt look right lol

s25hanh

iTrader: (8)

...and that is why I'm on here and not zooming down the 1/4 mile right now

be good

it looks uneven, that alerts me. on the plastigauge should be "if your plastigauge is flattened this much, you have this much clearence" type of gauge. what is that reading?

s25hanh

iTrader: (8)

it read .003 on one side and .0015 on the other. Thinking about picking up another 5.3 short block and parting this one out.

be good

did you upgrade to apr rod bolts?

s25hanh

iTrader: (8)

No sir

S10xGN

iTrader: (11)

Bent/twisted rods? If the shop didn't do any crank grinding, that's about all it could be...

s25hanh

iTrader: (8)

Im thinking it could be the crank as well. Will update this thread tomorrow after I call the machine shop.