Crank Polish Does It Need It?

[Sinbad 16]

Took my crank out my engine im stripping down today and all looks ok except for the tiniest line (im talking finer than a hair) on a couple of the journals.

Would this "go again" or would you recommend a polish?? Its so minute and can hardly feel it with my nail but i know its there.I would put a pic up but you probably wouldnt see!!

How much should i expect to pay for a polish as i dont want to be ripped as theres alot of chancers about in these hard economic times!

[SurGie 54]

Yes it would be good to get it polished, they all have to fit together precisely.

[Sinbad 16]

heres the measurements i have just taken in mm

Measured From Cambelt end of crank---------------------->

 

Big Ends-------44.9------------44.9----------44.9-----------------44.9

 

Main --59.9--------------59.9---------------59.9-----------------59.9---------------59.9

 

Is there a guide somewhere with the tolerances?????

[welshpug 1,657]

what did you use to measure it?

[Sinbad 16]

A digital vernier caliper,is that ok??

[welshpug 1,657]

no, needs to be rather more accurate, a micrometer is what you need.

[Sinbad 16]

it seems within the tolerances after reading the haynes

undersize big end is 44.671-44.690 and main is 59.681-59.700 ?????

might just take it to the reconditioners and get them to measure to be safe

[Tom Fenton 1,542]

If you have got those measurements with a vernier caliper forget it, they are not accurate enough for the kind of tolerances involved.

 

To be honest unless you are 100% confident, take it to an engine shop, have them polish and measure the journals, and supply you the required bearings. This way you are 99% likely to get it right (note not 100% as an engine shop can still mess up, check running clearances on dry build with plasticgauge to make sure).

[Sinbad 16]

Thanks lads,to be honest its going to the engine builders anyway to be checked.

[Sinbad 16]

All sorted,got it measured and polished at an engine builders this aft,very pleased with the price and the fact its in good condition.It was near enough standard size still.

Just need the bearings now,got a price of £46 for mains and £44 for big ends from the engine builders so going to have a ring around and see who wins lol

Edited October 11, 2011 by Sinbad

[welshpug 1,657]

do you know what sizes you need?

 

if its stock big ends you need then pug ones for the J4R engine are £25+vat for the set.

[Sinbad 16]

Whats a J4R engine? I have a 1.6Gti???

Yes its standard size mate.

[welshpug 1,657]

doh, they wont fit then

 

XU5 and XU7 big ends are 45mm xu9 and Xu10 are 50mm.

 

they are £35 from peugeot for the XU7, and £42 for the XU5.

 

 

same rods but I think the XU7 are just cheaper as they made more of them.

[Sinbad 16]

Ah right,nice one,i shall be going to see peugeot perhaps then if thats the case.

Thanks.

[Miles 331 1 Cars]

Complete sales pitch here, But I'm sure I have some Big end's for the 1.6 will check after dinner

[Sinbad 16]

Yeah let me know miles,need to be standard size mate.