14 July 2012

Attendance 4:

Even though it was officially a Class 15 working weekend today was going to be spent working on the Crossley power unit removing the pistons. Carl made a start removing all of the remaining split pins that were still in place on the splined locking caps from the big end bolts. Adam, Jason and Phil made a start on opening the tent up so that the Manitou could gain access later to remove the pistons. The folding back of the tent canvass didn't take very long so Adam and Phil then joined Carl in removing the last of the split pins that were accessible without having to bar round the engine.

Next Carl attached a device that he had made that allowed the seized piston and liner to be lifted out. It consisted of a piece of metal that lay across the top of the Liner and then 2 bolts either side could be tightened up and located under the lip on the outside of the liner. Carl then loosened off two of the bolts that were holding the big end bearings halves around the crank shaft and inserted a piece of rope through the two now empty bolt holes then tied of the rope so as to support the lower half of the bearing. Then the two remaining bolts were removed and using the rope the lower part of the bearing was gently lowered down so as not to damage it. The bearing half was then removed from inside the engine block.

Straps were then wrapped around the lifting device that Carl had made and once the straps were attached to the Manitou arm using a chain the piston and liner were ready to be lifted out. The lift proceeded, Carl checking that nothing was going to snag and making sure that the remaining part of the big end passed up the bore without catching on anything. In no time at all the piston and liner were lowered down on to the floor.

The rest of the cylinders could be lifted out using a lifting eye, in the middle of the cylinder head is a threaded hole in the which the lifting eye could be screwed. The big end was dismantled in the same way as the first cylinder that was removed. Then the engine was barred around until the Cylinder was close to top dead centre. The threaded hole was tapped out and the lifting eye then screwed in tightly. Then a block and Tackle was hooked onto the lifting eye and connected at the other end to the Manitou arm. Then slowly and surely the Cylinder head was lifted out using the block and tackle made sure nothing snagged. The Cylinder proved to be a bit troublesome as it kept sticking so it was a case of lowering it a bit then lifting again. After a few attempts it broke clear of the liner and was lifted out and placed on the floor next to the first Cylinder and liner. The rest of the cylinders were lifted out of the B bank in the same way, however it was discovered the more oil used to soak the liner sides the easier the Cylinders came out….

With the B bank completed a start was made on the A bank. Some more of the tent need to be taken down so that the Manitou could gain access. Also the tent needed some TLC as the ravages of the previous winter had taken its toll and some of the metal bars needed to be exchanged as they were bent. The A bank was dealt with in the same way as the B bank and by then end the last Cylinder only took about 20 minutes to remove.

With all the Cylinders remover the opportunity to bar over the crank was taken to make sure that there were no potential issues. The crank spun with no effort at all which was great news meaning there is nothing catching in the Scavenge Blower located at the opposite end of the engine from the generator. With all the Cylinders removed and safely stored away the tent was repaired/reconstructed and the canvas pulled back over. The inspection panels were put back on to the engine block and the tools were tidied away and this brought the day to a close.

Day two of this weekend was spent on D8233 - click here

If you wish to lend a hand please contact Chris Tatton

Above : The big end split, note the string allowing the bottom half of the bearing to be carefully lowered so as not to damamge it. © C15PS
Above : The cylinder and liner coming out as one, note the tool that had been built especially for this job by Carl. © C15PS
Above : Adam easing out one of the Cylinders with the block and tackle. © C15PS


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