McDonald Imperial Super-Diesel

Why drill the hole out? With the ferrule/olive removed it should pass through then fit a new olive and tighten the nut to seat it
Cheers Steve

Cobba, keep it coming, I am busy enough in Virus Solitary but watching you do all this tricky and difficult stuff is great entertainment, and I am learning a few tricks for next project... (as soon as there is no-one looking over my shoulder) thanks.

Hello Cobbadog, I have a SD model Mcdonald and the cam roller and cam lobe were badly worn like yours so I made up a new roller and filed the wear ridges off the lobe and the engine runs ok. Regards John

The cam looks like cast iron ,welding might be risky ...best to try it first ....Make sure the roller is round ,any flat spot will stop the roller and skid on the cam.

Thank you to everyone who have replied and all are viable.
To make a complete new cam would not be that tricky but setting it up in the lathe might be and above my ability.
The profile of the original cam is still in place as that lip shows. If I built this one up I have that as a guide to make it back to original.
Blackduck, what the f@#k was I not thinking, of course a new $0.50 olive and the job is done, thank you.
As for welding it up, there are cast iron rods available to use and I do have a big bunsen burner to heat to up before and after welding and to get rid of the oil that would be in the porous metal.
John D, I am liking your idea and is something that I can do on my lathe with the right grade steel and I think I have some in stock. Believe it or not my wife Dee ran that idea passed me earlier today and I dismissed it because I thought that the roller was recessed in between two pieces of steel but there is room to do the repair that you have kindly suggested, so thank you for that.

Now I CAN wait to tell Dee that her suggestion is going to happen. Boy wont I hear about this for some time to come.

Anyway, I have been just like a women going backward and forwards changing my mind on a whole heap of things so long as I don't start shaving my legs I think I will survive this turmoil.
Today I stripped off the oil pump and then cleaned out the sump and the area where all the gears run, what a bloody thick mess was inside here. So as it is now is good enough. As things came apart I found the shaft that the cam gear runs on has a slot machined in it for lubrication was choked so that part is cleaned up now. The oil pump was hiding so much crud behind it I could not believe that it just kept on falling out as I scraped away. So after cleaning up the pump I stuck it in my hand basin where I work and submerged the pick up of the pump and spun the gear by hand slowly. Nothing happened then wound it back the other way and presto, it works. Spun it faster by hand and the water spun out like a hose so when it get oil back inside it certainly will pump well. I blew out the water and filled the inside with Lanox then sprayed the outside as well. Next was the oil pressure indicator on the outside of the engine. It was stuck in the IN position so with a bit of Lanox on the outside and I turned the brass elbow that connects to the oil pressure line to facing upwards and filled it with Lanox and left it for a few hours. At last the small button that is suppose to extend out when there is pressure was freely moving. So when it is all the way out I filled the elbow with Lanox and pushed the button in and it pumped out the Lanox so this looks like it will work as well.
Next challenge apart from the cam gear is the water jacket around the cylinder, this will take a lot of doing but I have a very cunning plan for it.

more pics for your entertainment. Again, sorry that the pics lay down even after standing them upright and saving them in that position before posting.

All that crud is a bit like inside the bellhousing when I removed the gearbox on the O type.

Satisfaction is looking at a clean engine AND having pictures to show what it was like before you cleaned it .

What are all the journals like?

From the sound of it there may not have been a lot of oil getting to the bearings.

For an unknown reason both mains and the big end are in great shape. One of the bits of news in the letter mentioned below was that these wroked on 6-8 psi oil pressure and the rest is splash fed. IT is the splash part that I feel has failed due to incorrect oil level and probably more than once. To lubricate the gears the oil is picked up by the teeth and as you know the oil winds its way up and finally is flung off. By the time it gets to the top gear, the governor gear I can't imagine much oil left. Then from the highest point oil drips down and onto the cam and the cam follower which is where the roller is and failed due to being dry. Sometimes I want to re-engineer stuff that I find has failed and run a seperate smaller oil line up to the top and squirt it downwards, but then if the correct oil level was there this possibly would not happen, so leave shit alone Cobba.

As for the reasons why they get a lot of crap inside I feel it is due to "maintenance by breakdown" program. While it still starts and runs dont fix it.
No work done on the engine today as work has snowballed yet again and a seat with a cuppa was high on my list of things to get done. Before home I did my usual stop at the post office to collect the mail and recived a reply from the the McDonald Register. What a detailed reply I got along with brochures covering the SE & CE models. A hand written letter with a heap of details I was chasing like the thickness of the head gasket material and a tip for fitting wider rings onto the piston and yes there should be an oil ring down the bottom, so this is something else to follow up on soon.The original Work Orders have been kindly supplied with the Customer/s name and town they lived in. One as I had already know was delivered to Bohnock on the Manning River East of Taree towards Manning Point. The other went to Belbora which is just to the West of Taree up near Comboyne. So they are both local to me, well failry local.

Still looking for a replacement oil primer OR details of what is inside of them please.