Rebuilt VN V6 wont turn over.

[Shaun_VK]

Hey just a quick question,

I have recently rebuilt my VN V6 for my VK conversion but after redoing all bearing and rings the motor will not turn over by hand but before the rebuild it did, with each bearing cap we tightened it got harder and harder to turn over, now all back together it wont turn over no matter how hard you try, lubed all bearing on instal and is all done to factory workshop manual specification. Have I done something wrong or is it just due to new bearings and rings?

[Not_An_Abba_Fan]

I'd say you may have fitted the incorrect bearings. Oversized bearings to a standard crank maybe.

[FXST01]

Did you put the caps back on in order and the right way around?

You did only lube one side of the bearings?

[VK SL 3800]

You need to check a few things:

Bearing caps have gone back onto the original rods and mains
Rods are installed the correct way around, EG: bearing tangs are all facing towards oil filter side (dont know which way its supposed to be the book will say). My ECOtec manual say the orientation doesnt matter :/
Bearing caps are installed with Tang to tang - the bearing tangs are on the same side as each other on the rod and bearing cap, same with the main bearings on the block but they should have arrows pointing to the front anyways.
You need to have end float/backlash on each rod, with the cap up and tensioned you should be able to move it back and forward a little bit, there would be a spec but so long as you can move it a little and its not slapping around it will be fine.
Crank end float, if the crank can move back and fourth with light force from a prybar or screwdriver it should be fine. Spec in the book will be something like .002''-.012'' probably less its just an example.

If you still cant work out why its seized get some plastic-gauge and measure you bearing clearances one by one.

But it sounds like you have fitted oversize bearings as NAAF said.

[Colby844]

i remember talking to someone who assembled his beautifully machined crank back into his engine only to find it seized solid- after a stack of questions i discovered behind his shed another same engine in bits so asked if by chance he had gotten anything mixed up- he said nup no way man i know what im doin but i did swap the mains caps with that engine cause i reckoned them looked in better knick!!! HA! Bingo! you more than likely would not have done anything like this but yes it can catch some peoples out

[VK SL 3800]

i remember talking to someone who assembled his beautifully machined crank back into his engine only to find it seized solid- after a stack of questions i discovered behind his shed another same engine in bits so asked if by chance he had gotten anything mixed up- he said nup no way man i know what im doin but i did swap the mains caps with that engine cause i reckoned them looked in better knick!!! HA! Bingo! you more than likely would not have done anything like this but yes it can catch some peoples out

'


You should never mix and match caps, they are tunnel bored from factory and different caps can cause misalignment.

[Shaun_VK]

I used standard sized bearings and as far as i know the motor was completely stock when i got it, its being wired up now so im hoping that if they turn it over it dosent snap a rod or anything, see what they say when i get it back from the auto elecy i hope i dont have to pull it all out again and redo the bearings, also the caps were placed in order and replaced back into the motor in order.

[Jxw]

a fresh built motor even with slightly tighter clearances than std should still be able to turn it over by hand..... did you actually mark the big end caps and piston/rod assemblies with their corresponding bore number? or just sat them out in order and possibly mixed them up when you put it back together?

You need to be 100% sure it was put together right before starting it or you'll end up finding something like this inside if you mixed the caps up or put them around the wrong way.

[Not_An_Abba_Fan]

As VK SL 3800 has said, if the caps are around the wrong way the tang will jam the crank. But from what you said as you tightened the end caps the crank got harder to turn, it would have to be either the caps are back to front or they are the wrong size.

I had an incident a while ago installing a cam to a 4.1L Falcon crossflow where I must have not gotten a cam bearing sitting exactly square, it wouldn't turn over with a long pipe on the crank bolt, but once it started and ran for a few minutes, it loosened up lol.

[Pub247]

i wouldnt fire it up if its not turning over your liekly to break something