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Colin Hough


I am soon to face the decision of how to set up the oil supply to my re-assembled ’59 model, hence reading this post and also looking at the Technicalities (which only leads to confusion!!!!)

I offer the following for information:

1) With my first Scott (also a ’59 model) which I bought in the late 1960’s there was the original instructions from Geoff Milnes with it (and I still have them so I must have planned to get another Scott someday). This says: “Check the oil pump to see that it gives 15 (fifteen) drops per miniute each side with the engine idling. Add an eggcup full of oil to each gallon of petrol”. I don’t know what a ‘standard’ eggcup size is, but I guess this was around 100:1. I used conventional single grade car engine oil and all worked fine for general use around home and trips on ‘ordinary’ roads. However, holding 70+ mph on the motorway going to the IoM TT races resulted in a big time seize after about an hour. This was ended my Scott ownership at that time!!! There was no comment about turning it up for long distance high speed riding (but then, motorways were not around when this was written).

2) 35 years, a wife and two kids later, I have now returned to Scott ownership and am reading the Technicalities in trepidations of having to set up the oil supply to my ‘new’ Scott after I (finally) re-assemble it following an engine overhaul by Tim Sharp. The key reference I have found is from Brian Marshall (Yowl V20/9 April 1998 article headed NO SMOKING):

In summary, he recommends a fully synthetic two-stroke oil such as Castrol TTS and Silkolene Pro 2 & Comp 2 and says “personally, I think that a combination of Pro 2 and Comp 2 is the complete answer” to no smoking and good lubrication. “Pro 2 is a self-mixing grade and can safely be used at 40:1 in a petroil lubricated machine. In a more typical Scott with a Pilgrim pump or drippers, I would use it in the perol as an upper cylinder/top-end lubricant cum belt-and-braces [that’s belt and suspenders for our American cousins] measure at perhaps 50:1 or 60:1, and then use Comp 2 in the oil tank, at a delivery rate of NO MORE THAN HALF A DOZEN DRIPS PER MINUTE in each side of the engine at a fast tick-over. That is ample to keep the glands and big-ends happy. I cannot over-emphasise that such a low delivery rate is unreliable in a Pilgrim pump unless it is in good condition AND geared down. This combination gives excellant lubrication and very little smoke. Later Scotts (e.g. 1946 onwards) have no oil tap as standard, and as a result oil tends to seep through the pump and flood the sight glasses and crankcase wells”.

As my machine is fitted with both a reduction gear and an oil supply on/off tap, I intend following Brian’s advice.

However, Glyn Chambers (our local supply source for Silkolene oil) noted back in Jan 1972 (V7/9) when writing about the problems of getting Pilgim pumps to work reliably at the low rates need by Scotts that the “biggest sin you can commit (I know, I did it) is that on finding the pump somewhat unreliable, you turn it down a notch and put some oil in the petrol thinking this is ‘belt and braces’ technique. Unfortunately, this makes the pump worse. Please don’t put oil in the petrol, it doesn’t need it. Turn up the pump to the maximum you can get away with without becoming a pollution hazard e.g. one in 5 or 6 for normal running or about one in 3 or 4 for fast work . This is far more oil than it will ever need but it keeps a good pump reliable. If you drive in the Metropolis – buy a Honda. If you are a fast bloke – develop an instant left hand”.

Remember, this was 1972 so the environmental issue of smoke has moved on!!! Having talked to Glyn when I first got my ‘new’ Scott, he strongly recommended getting a reduction gear to slow the Pilgim down and hence avoid this problem – it was on his advice that I got this mod. I include this as a warning that simply use a ‘half and half’ approach may result in the Pilgrim failing to perform – note that both Brian and Glyn advise fitting a reduction gear.

I will discuss again with Glyn when I go over to pick up supplies of Silkolene and see what his current recommendations are.

3) I am also challenged by how to do the initial start-up i.e. with the oil tank full but the pipes empty. My plan is to:

i) Fill the oil wells and then close the doors.
ii) Turn the Pilgrim to max open so the oil runs through fast.
iii) Put in the first fill of perool with a relatively high pertroil mix (say 40:1)
iv) Kick the machine over a number of times with the plugs out to get petroil distributed.
v) Put in the plugs and kick it for real (and pray).
vi) Turn the pilgrim down as soon as I get a lot of smoke coming out (I will warn the neighbours first!!!)

Does anyone have any advice on how better to do this?