Itís been a few years now and have been rallying this engine continuously throughout those years, Iím now completing restoration of the Ruston 3RG and have decided to do some serious improvements that have been building up .
The Gardner was one of my early restorations very soon after being introduced to stationary engines let alone building one (in fact until I acquired this engine Iíd not even heard of a hot tube engine), I put new rings in but was not a good thing to do considering bore will have worn oval but has done well for a long time now.
Also I fabricated a crank as have been shown in these pages, however it should really have been a temporary measure but as usual temporary became permanent, I was never able to get totally true so went with it so I now intend to do a casting and machine a new one from one piece.
As for cylinder and piston Itíll be far cheaper to have a piston cast (already have a pattern from making a new piston for a friends Gardner 1F a year or so ago) and then have cylinder bored till cleaned up and make new piston to suit with new rings.
Exhaust valve chest was badly corroded away when got engine which I had to make a phosphor bronze guide for, this was a very thin item and has always been a nightmare to get to seal on cylinder.
Iíve had a new one cast from a friends engine albeit a solid lump as having foundry cast with inside detail as well would have cost a fortune, Iím attempting to machine inner detail as best as can on my mill.
Crank splash guard from new would have been gun blued, however! mine was corroded and not possible to do this so was painted black, Iíve removed brass edge trim and am in process of making new fro a sheet of steel and then hoping to find either a way to blue it or someone who does this sort of thing (hard to find these days).
Over the years Iíve found that this engine once started will run all day faultlessly as long as there is no breeze (would not have been used outside during working life), Iíve tried on more occasions than I can remember to alleviate this problem but although improved a bit, never cured it.
I may have another look at this issue during rebuilt in a hope of making it reliable in a wind.
Iíve already made a start on this re-rebuild and here are some pictures of progress so far.
Packing crank to 2.5mm over size for machining after casting
Exhaust casting ready for machining
Just another addition to the story, Iíve now finished the exhaust vale chest having to machine inside as far as could (could have had cast with inner detail but this would have required having a pattern made and price would have been too high (experience some of this)), I finished throat of unit with rotary burring tool.
Also started machining new crank having received casting from foundry, here are some images from commencing machining.
Comparison of two chests showing how degraded old one was
Maching flywheel end
Maching drive end
New one built up
Having gotten so far with crank I need holders and a special tool for the rest of operation, also being a bit apprehensive about it Iíve left for now and making the new piston.
Small end clearance
Pin machining set up
Piston is now complete and new rings are gapped and ready to go onto piston, leaving off at this stage as not fitting piston to rod just yet, when crank is machined and fitted I need to set up big end on crank and donít want piston flopping around.
Just oil groove
Iíve also faced the gasket faces on cylinder and combustion chamber
Machining cylinder faces
Combustion chamber faces