Bearing Selection And Measurement

[mhyphenl 10 1 Cars]

I've now got my XU9JAZ engine totally stripped and cleaned ready to rebuild. I want to try and get this all right on my own before I bottle it and send it to the local engineers. I've used digital calipers to measure the Main and big end journals on the crank, it seems in really good condition with no scoring and even wear. The mains measure 59.94mm and are round, the big ends are 49.97mm also round. I Also measured the main crankcase/ bearing cap opening at 63.71 on all 5. Now 59.94 is slightly below tolerence but with the condition being so good I was looking to use the bearing grade choice that peugeot give to take up the slack. The top grooved bearings are 1.856mm and the red marked bottoms are 1.870, the journal to cast gap is 3.77mm, subtract the two half bearings gives a clearance of 0.044mm which is well within tolerence. In my mind this will avoid grinding the crank until next time, does this make any sense or am i totally wrong in my thoughts. !!

[welshpug 1,657]

sounds like you're going down the right track, though you really need to use a micrometer rather than a caliper as they are a little more accurate.

 

nothing wrong with asking your local machine shop to measure up for you though.

[mhyphenl 10 1 Cars]

I really should have bought a micrometer as well but couldn't afford them, got the callipers to measure internally too. The guy over the road that does up old cars showed me a technique to get pretty accurate results by gently applying closing pressure and gently rotating the caliper to assure getting the minimum measurement! Seemed to work quite well! Bearings are going to take week from pug but I'll let you know the plastiguage results when in!