how tight
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hi guys how tight should the engine be to turn over by hand once big ends and mains are torqued up

engine is as follows

new +20 pistons and rings
fresh rebore
new mains and ends
all tighternd to the settings in haynes manual

with just the crank in and tighternd could turn the crank by hand
with pistons in and tighternd i have to use a spanner in the grove of the crank and its quite stiff
is this right ?

thanks dan

rings can do this a bit,

put it at tdc and rock it over a few deg, if its still stiff there then look for a tight bearing, slacken them off one at a time and try it and see if it suddenly gets easier.

thanks ill give it a go

Check you have your mains caps on the right way round and on the right rods

yeah all in the right place ill check what joe said and see how i get on

if the crank spins on its own freely, give all the big ends a wiggle, if they move on the journals then its just the tension in the rings

Like the lads say, do one at a time,

I always put a cap on at a time, nip up, turn.

If it suddenty goes stiff then you know why. If all the caps are the right way round, you might have mixed them up.

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right ive undone to outer pistons and it turned freely so tried the caps on the opisite rods and it just locked as soon i nipped them up so put them back nipped up and still turns ok but as soon as there torqued its tight to turn ? the crank has just been reground to +20big end +30 mains should i have the two journls messured again

check you have the correct sized bearings on the big ends.

will do as they could have been packed wrong i spose

bearings are the right size so all thats left now is to have the crank looked at ?

Have come across a bent crank before. I would get it checked to avoid tears later

yeah gona take it back this week and get the guy who done the regrind to have a look over it for me

Have you plastigauged the journals?

Always something I do just to make sure everything is as it should be.

Give it good turn over by hand, as many times until you are bored.

Take it take each rod cap off one at a time and look for light scoring, this will be where is is nipping up.

JF.

check the rods are the right way round, they are offset,

yeah rods are in the right way and want turn it over to much a ruin the nearing im just gona have the crank re messured

It just sounds to me like the caps are mixed up on the rods, I had same problem so torqued the crank up then the rods one by one changing caps around if it locked up until I could have all four tightened up moving freely. You'll find it'll just be one giving you jip.

First thing to check, make sure the crank in the rods is the correct way round, so the little end of the rod isn't thrusting against the side of the piston.

Make sure you have the correct amount of big end clearance between the rod and crank web. I can't remember what the A seires rod clearance is but we use 6-8 thou at work.

Next thing to look at is the radius on the crank, where it has been reground. Is it catching on the side of big end shell, causing it to nip up? If it turns freely with the caps not fully tightend and then nips up when they are tightend up, its either the shells catching on the radius of the crank, or the wrong size journal/bearing.

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1/4mile in 13.2sec @ 111 terminal on 15psi