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18-6-2016 XB12 repair swallowed screw

27-7-2016 - 18-6-2016 XB12 repair swallowed screw

cylinders came back bored oversize with new pistons.. time to rebuild this uly

i will save this piston as a souvenir for the customer

with a piston pin puller you can get the , usualy sticking pinpins out easy... heating the pistons is a other option... hammering theme out not !

sheeesss unlucky

cylinders came back well packed to protect the fins from damaging

nice , new bore , no first clean these soapy watter works best , they look clean but honing abrasive is still in... check with a clean rag, it it douse not pickup any dirt there clean to start asambly

when you get your cylinder back marked, usualy for a good reason

checking piston pin bushing play... needs to slide with a little stick, and don't feel any play

keep the markings to getter, means the pistons are mesured and the cylinder hone is made to match the piston in TQ plates

oil scraper rings , firs the spacer , than the 2 whiper rings

even the piston rings are already gapped..

off course you check this any way !! put the ring in the bore and push it down with the piston as plunger, so the rings are level to mesure correctly

i used a old TQ plate as a spacer when the cylinder dowls are in , so i have a flat surface that douse not dammage

piston ring gaps positioned , break in lube coated the cylinder

and with a ring compressor clamp the rings and tap the pistons in the cylinder

piston pin in ready to be mounted

base gasket on, piston pin in the rod, i put for safety some rags in the cylinder bore , before i mount the piston pin clips , the clips can fly under tension and you don't want these to end up in the cases

cylinder pushed down.. and temperory fixed with some special nuts , you can use the short head bolts with a 1/2 drive socket to hold the cylinder down

markings important

as are the pistion and orientation off the rings , read the instuctions

last check for orientation piston in the cylinder , if they are worng way around you can just twist the piston, the rings will stay in place

now unscrew the piston stroke limit screw from the head ;-)

and a little cleaning up , not perfect , but it will do .. given the budget we need to keep this repair in

ushrod top rings mount these first in the cylinder head and oil theme a little

pushrod covers back on

and first push the head over the top off the covers then find the dowls to position the head

new head bolts , the old ones where so much corroded needed to hammer a smaller socket on to get these out

front head the same

and tq down the head bolts, follow the instuction from the head gasket manufactor

bump sticks back in... if the markings are gone long one is exhaust

and rocker box back on, locate all bolts first and start with the big bolts tightening, slowly and keep the box as level aas you can

and tq down the rest off the bolts

rear one the same but keep a eye out for the head temp wire , can be easely get caught between the box and the cover