![]() ![]() If there is not adequate compression in the cylinder at the ends of the stroke, over-travel of the piston will attempt to lift the cross head, and then, when steam is admitted, slam it back down. the flywheel is turning clockwise when you are standing with the cylinder to your left, and the flywheel to your right, the cross head will always be pushed or pulled downward toward the guide. If you eliminate the excessive clearance on the crosshead slides, you might not completely eliminate the knock. This engine was well used in its day.There are adjustments on everything else but the crosshead and guides are its weak point.Ĭan any of you great guys suggest a fix so I can run this engine without this annoying knock? I've got to be missing something here.Thanks for any suggestions! Lester Bowman. 015 thick shim and the problem of holding them in place still persists.Īt this point I wish to keep the engine looking original as possible.in case it turns out to be an engine of historical interest.But for the life of me.I cannot see an easy or sympathetic fix for this excess clearance. Then I considered a shim with a "bent up edge" on each end to keep them in place.But this is only a. ![]() ![]() Then I thought a simple brass shim attached to the crosshead grooves would be expedient.Maybe use Devcon or something similar to attach the shim.But this isn't old school and I'm old school. So I thought.I could tin the inner bearing points of the crosshead then Babbitt the guide slots and re-cut the groove to fit the crosshead guides.This might involve truing the the crosshead guides as well.But tinning the crosshead might be a problem because of oil in its surface. The problem is the crosshead over runs each end of the crosshead guides.( see fig.4 )This is as it should be as the crosshead doesn't wear a ridge at the ends of the crosshead guides.But the lack of any adjustment creates the problem.įig.2 shows the second problem.There is very little clearance between the crosshead and the upright bearing blocks which carry the cross shaft.If four bronze shoes could be made to mount to the top and bottom of the crosshead.these could bear on top of the crosshead guides.But no.they will foul the upright bearing blocks. Still being in the process of documenting this early little engine I loathe to change anything its original builder designed into it.But the knock is a problem which needs to be dealt with and I'm asking for help as to how it can be rectified.without any unsightly changes to the original design. Jim and I discovered if we press down on the crosshead while the engine is running the knock nearly disappears. 032 inch.This includes top and bottom clearance. The third image shows a rough drawing I made to indicate where the excess clearance exists.a good. We had an excellent steam man at this little get together ( Jim Van Hook )and I together we went through the various tests to determine where the knock is originating.The engine in in alignment and the piston has cylinder head clearance.The main bearings and rod bearings are not an issue.We have narrowed it down to excess clearance between the crosshead and the crosshead guides.The second picture shows this crosshead.It has no adjustment for wear engineered into it. I have this small engine which I'm still researching as to whom may have made it.I had a wonderful time this fall steaming it with a friends boiler and it is a sweet runner.Only one had a heavy knock.
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