Running in with todays pistons

[Steve Bryant]

What is now the current RUNNING IN  procedure for Austin Seven engines with the modern pistons as now being sold by our cherished suppliers ?

Thanks, Stephen

[GK5268]

Both mine & my Uncle's cars (Mk I Rubies) are currently being run-in with new pistons, we are both using SAE30 straight engine oil and will change it at around 200 miles (done about 150 at the moment on mine, Uncle's is at about 100 miles), I am going to re-fill with fresh for another 200 miles or so, then I will change to a modern 20/50 multigrade, the SAE30 should allow for wear to take place to get it all bedded in, then a modern detergent oil will keep the internals cleaner (after 1,000 miles before the re-build when the engine had been thoroughly cleaned, there was a surprising amount of sludge inside the engines...).

Oiling of the plugs seems to have improved (fitted a high-comp heads to both cars) but burning oil, which I am hoping will improve as everything beds in.

I have not been keeping revs down unduly, it is just not practical when faced with all the hills around here, but on the level, the car bowls along quite nicely in top gear.

Engine seems to be quite eager and on the level, the car seems to get to 30 mph without much effort, I am now using a GPS speedometer and this shows that the car's speedo is under-reading by a few mph and I think that has to do with the drum setting, as when stationary, the reading is not at "0" but to the side, I don't want to interfere with the instrument and the GPS is fairly reliable.

Gary

[Ian Williams]

The important point as I see things is to avoid letting the engine idle for long periods when you fist start it in the mistaken belief this will help the initial bed in, the rings need to be loaded or the bores will very likely glaze, excessive revs early on will also cause this. After a rebuild I like the take the car for a short gentle run immediately after the initial fire up, I then dump the engine oil, this is an unfiltered system remember and no matter how careful you have been dirt from the rebuild and swarf from the initial fire up will be circulating. The engine is then driven reasonably normally avoiding high revs but not excessively nursing it either, a few hills are good they really help load the rings. I change the oil very regularly during the break in period to keep it clean, oil is far cheaper than all the money you have just lavished on a rebuild! Running in oil may be a good idea but I have never used it.

[Colin Reed]

What is now the current RUNNING IN  procedure for Austin Seven engines with the modern pistons as now being sold by our cherished suppliers ?

Thanks, Stephen

I take it that both Engines had rebores or just honed

[Bob Culver]

The running in rituals of old were based largely on the needs of often tight hand scraped big ends.

JCL, major Australian ring manufacturer, recommend that pressure fed engines are warmed up at brisk idle to fling oil then taken for a run and rings deliberately loaded in brief bursts at medium speed.Aimed mainly at plated rings. A very early change recommended, not beyond 300 miles.. (Can use filtered old oil, or minimum quantity new)
With a Seven probably more than enough oil splashed about at any revs.
The cyl pressures in a stock engine much lower than moderns.
I suspect most of the metal in oil comes from timing gears. A magnet seems worthwhile. VWs ran 3000 mile oil changes with no filter.
Particles mainly wear the crank but original non hardened good for 100,000 miles or so, and hard Phoenix should be everlasting.

I am not sure that simple draining carries away much, but, except very first, can be dribbled thru a modern filter and reused. At no pressure much will be captured.

Attitudes to spending on Sevens are now very different from years ago! It has become rather like religious offerings!