To de-mod or not to de-mod?

Nick,

Don't be a spoil sport, I love winding John up its a good sport. Talking of the devil he has been rather quiet of late not heard from him.

I think if it is done discreetly, any mechanical mod that makes an engine run better is justified, especially if it reduces its consumption of oil or petrol. When I've got an engine running, I take it to an event where I can sit & listen to it for hours, leaning off the carb & swapping plugs to find the best combination - you can make some dramatic improvements to engines that were jetted to run on load & are now just idling their days away! I once halved the consumption on a Petter PU4 compressor by doing just this. In the end, the NGK plug I ended up fitting was pale chocolate brown, the cylinder barely hot after running for an hour on a sunny day.

The gap between cylinder & bore can probably be reduced as oils are an order of magnitude better than they were even 50 years ago. You might like to look into ring design & see what is available.

Cleaning the inlet tract of casting flash, gaskets that stick out into the tract, cleaning up seat shrouding will all make a difference.

Turning to two strokes, dedicated silicone oils are so much better these days, it is perfectly OK (my opinion, you understand ;o)) ) to lower the oil content in petroil mixes. Again, experiment will be called for.

With petrol the price it is, green concerns & carbon footprints, I think this is a responsible (and frugal!) policy.

But I'd not go so far as to change the carburetor.

Regards,

Kim Siddorn

This is one of "those questions" that come up here from time to time. Opinions are mixed, but generally speaking there are those that like to repaint anew as the conclusion of a restoration and those that like to wipe their Iron Charges over with an oily rag & make 'em go!

I am in two minds as I think there should be both pristine show standard, chromed nuts 'n all engines to see. We know very well that all manufacturers made them for their stands at big shows. Indeed, I have a Douglas SV twin that was obviously intended for just such a purpose. However, the great majority were workaday working lumps & (instance) the nuts were painted over along with the castings they held together.

Personally, I think that if it is rusty beyond recovery & needs rescuing rather than simply restoring, then a complete new painted finish to be proud of is part of the recovery process. The WW1 ABC generator I'm working on ATM is like this: the fuel & oil tanks were rusted right through & needed a new one from Frank the Tank. This I had sprayed a gleaming, deep black & will go to some lengths to create myself the new waterslide transfers that will grace its flanks. It is rare for me to go to these lengths & usually a practical "honest" job is all I run to!

However, mechanical restoration is another matter & I'd be quite happy making new bits to a higher specification than those used when new, machined to closer tolerances and finished in a way that will ensure they are able to continue in service for many years.

Just because the original lubricant was little better than bacon fat, that would not stop you from using modern silicone oils to lubricate the inward parts of your pride & joy, would it?

Regards,

Kim Siddorn

"THE DOUGLAS STATIONARY ENGINE RESOURCE (admin)" wrote in message news: snipped-for-privacy@brightview.co.uk...

Anything that smells like cooked bacon as it runs sounds like a winner to me :-)

kimsiddorn wrote (snip):

But what, as was the original intention of the thread, are your feelings on those mods and repairs that an engine may have gathered in its years use and abuse - something to be rectified or a cherished part of the unit's history?

NHH

1. Is the mod more historically interesting than the engine itself?
2. Is the mod well or badly done? It would have to be exceptionally well done to make this a reason to keep it, but nasty botches should usually be removed or reworked more neatly.
3. Is the mod interesting? A humidity-regulated governor on a mangel- wurzel chopper would be worth preserving.
4. Is the mod in period with the engine? A 1930s fix to a 1920s engine might now be seen as "of an interesting historical period", especially if the materials are in keeping. A 1970s hack with PVC hose wouldn't be.
5. Is the condition of the mod comparable to the engine? Does one make the other look better or worse?

Thanks Nick, that one slid past me!

As long as mods had been done well & were for better performance AND they were still working, I'd leave them alone. But if (say) an LT magneto had been replaced with an HT mag that was now faulty, I'd be likely to restore it as it was originally.

Regards,

Kim Siddorn

I'd pretty much go with that, though I wouldn't necessarily restrict it to 'performance' mods in the SE context.

NHH

A pretty good check list to run through when considering the fate of a non-standard 'feature'. I rather like to see some of those copper sheet and dozens of 2ba screws frost repairs on a 'working clothes' engine for instance, but it would look awful on one done up to the nines.

NHH

Years ago, I watched a man patiently drill, tap & stud a frost crack in a Lanchester block. Took him all day but it worked!

Spoilsport :-)

Our PC died a while back and I've only just got back on line. Now who mentioned paint?

John