Good day MQuinn, Sorry I didn`t get back to you sooner, been in hospital.
I suspect that the issues you are experiencing are due to the old selenium rectifier failing. When they do fail they usually release a very toxic chemical that smells slightly like garlic. This rectifier converts some of the AC current generated into DC current which then flows through the field windings to produce the North/South poles that the armature spins inside. Without this energisation of the field windings your generator will produce no power except that relating to residual magnetism.
Behind the two covers on your generator head there are two rheostats and the old bridge rectifier. The rheostats adjust the load/no load output from the generator. Test continuity across them with a resistance meter, I would expect to find resistances of between 1 and 20 Ohms. Check the condition of the slip ring brushes and that they are free to move inside their brass sleeves. Check for continuity between the two slip rings with a multimeter, I would expect to find a resistance of less than 100 ohms between them, if they are open circuit the armature windings have burned out and will need re-winding. Check for continuity in the field windings (two wires that run from the bridge rectifier to the electromagnets mounted inside the outer perimeter of the casing), again I would expect to find resistance in the 10s of ohms, open circuit will require a re-wind. If all the above checks are OK then replace the old selenium rectifier with a modern silicon bridge rectifier. These are readily available on Ebay, ideally get one rated to 1000 volts with screw lugs and a heatsink.
I attach a couple of pics showing the two rheostats and the selenium rectifier.
let me know how you get on.
Bob

Hi Samo, Rob at Old Timer Engines in Queensland will probably have what you are looking for. He used to have quite a few CS engines that were beyond economic repair.

Bob

Hi Bent Trigger, yes there is a lot of internal dirt shown in your photos. There is a product called flushing oil which will remove most of it without a complete disassembly. Get the unit running and then drain out the oil. Replace the oil with flushing oil, run the engine up to normal working temperature (probably around a half hour run but follow the instructions on the tin), drain out the flushing oil and replace with regular oil. Do not throw out the flushing oil, let it settle and it can be reused.

Bob

Hi Rene, I agree with Cobbadog. I recently had a small Honda petrol engine in my workshop, it was overheating and seizing after only a few minutes run time. I striped off the covers and found that all the cooling fins had been filled up with mud wasp nests.
The only other thing I can think of is that you have some sort of lubrication problem, possibly too little oil, wrong grade of oil or oil is contaminated with diesel.
Has this engine been rebuilt/rebored recently? It could be that the clearance between the pistons and cylinder walls are too tight or that the piston ring gap is too small.
Let us know what you find.

Bob

Well done VP, that should do the job on the return line. Make sure you remove as much flux as possible, nasty corrosive stuff, very bad for fuel tanks, lines and injectors.

Bob

Hi Powdermonkey, I`m sure it works very well in Florida. Try it somewhere where temperatures drop below freezing at night and you will be looking for a new cylinder block. Sufficient ethylene glycol antifreeze for a 50 gallon barrel is going to cost many hundreds of dollars.

Bob

I have used both copper and Dowty washers in many situations in the past. Of the two I prefer annealed copper because it does not decay like the neoprene O'Ring in a Dowty washer. Many years ago I had to fight a fire in a very large air compressor, a dowty washer had been weeping cooling oil onto the internal electric drive motor. The vertical chimney and cooling matrix was also full of cooling oil. When it caught fire it went up like an atomic bomb. Four engineers managed to control the blaze until the fire fighters arrived. Hundreds of thousands of dollars of damage!

Bob

Hi BruceM, I`m hoping the wiring insulation is going to be OK. There are four things that PVC hates: time, hydrocarbons, heat and rodents.
This was made in 1976 so it`s old enough for time to have taken it`s toll. I had to replace a lot of exposed PVC cabling around the engine.
There was a leaking diesel fuel line that some idiot tried to fix with a pipe clip rather than replace the rubber fuel line, so the entire unit was covered with diesel that had dried into a nasty sticky varnish. This was previously owned by the New South Wales State Emergency Services, a hot day up there would be 50+ centigrade in the shade, plenty of opportunity for PVC to degrade. I did dig a few mouse nests out of the sound proofing but haven`t seen any eaten cabling yet.
I have lived through one mouse plage and seen the damage these little buggers can cause, just as an example; they tried to get into my chest freezer, they could not get in through the top because I had loaded it with concrete building blocks. Didn`t stop them from eating all the wiring and insulation underneath the unit! They also ate the rubber water pipes on my Wife's car, luckily we only took a short journey and didn`t seize the engine.
I`ll let you guys know how it goes.

Bob