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Well, a big box of bits came from Paddock's, so just waiting on some final pieces. But it mean a slow weekend - I guess it happens. Current target is to get between 2 and 3 Sundays a month on the car to keep domestic harmony and real life balanced.
But it has let me ponder a question. Once I rebuild my engine, stuffed full of graphogen and cam lube and new running-in oil, should I start it and bench run it in, or should I leave it until the car is ready to roll. I want to start it up, but have heard horror stories of not bedding the rings in properly and so getting terrible oil consumption - which I don't want.
So, any thoughts out there of the pros and cons to now versus delayed?
I would definitely spin it over to check compressions, oil pressure and circulation but maybe not fire it up...
If it's going to stand for a while again I would put some oil down the bores because it's almost impossible to prevent condensation on the bores, unless of course you take it indoors and keep it warm...
As for starting, then standing causing excessive oil consumption, that's a new one on me. I have had engines large and small stand and it's never happened in my experience, unless of course they have been thrashed from day one...
One of the best ways of ensuring low oil consumption is honing the bores properly, with 45º cross hatching, if that isn't done well then you may get excessive oil consumption. It's a slow painstaking task but worthwhile.
Sorry Ed, I wasnt clear. I was referring to the need to run the bores in, without which the rings evidently will never seal. And it is this aspect of running in that bothers me, if I just start it up occasionally to make me smile, will I be ruining the chances of getting the rings to settle.
On the original rebore, the cylinders have been nicely cross hatched, so I think it will be fine, subject to my concerns about whether to just run it in for 20 hours on the bench, or wait for it to be on the road.
Running an engine for 20 hours on a bench won't run it in. Not unless you have a dyno to load the engine of course...
In my opinion starting it occasionally to move it and enjoy the experience shouldn't do any harm because in 'normal' use the various pastes and additives will be wiped and washed off the cam and other critical surfaces in minutes so they amalgamate with the engine oil pretty quickly in any case. The important thing is to be sure you have oil circulation, take the filler cap off and check the rocker shaft is oozing and splashing in oil.
An engine needs a load to run it in and make the rings 'work' I have had several large engines, among them a Cat D4 and Volvo 12 litre truck, which when started smoked like crazy and would do so all day if left just ticking over, within a minute of making them work the exhausts were as clean as a whistle and stayed like for the whole shift.
You have to work an engine to get it running right, that's what it's designed for and it takes at least 15 to 20 miles to get it warmed up properly. One reason why racing car engines wear out so quickly, they don't have time for the working temperature to soak right through the entire engine and get the tolerances right. Formula 1 engines are heated overnight so when they are started they are on song from the start, else they would seize and fly apart before the first corner.
Interesting, thanks. So your view would be the occasional morale boosting start up will do not significant harm.
As to running in, I wnder what "load" does to the pistons, as they only go upand down, so I would imagine revs more than "load". Towing a tractor woul still only require an up and down motion. So there must be more science to it than I can appreciate.
But can definitely see that the operating temperature will make a difference to the oil flow and movement of parts. Would an oil pre-heater make sense? I have seen them advertsied for winter use, so any thoughts please?
If you read the instruction manuals for 50's - 60's cars they suggest a 500 to 1,000 mile 'breaking in' period. This means driving normally without revving the engine too hard nor letting it labour at slow speeds, driving gently (not towing tractors?). This gentle driving can be gradually be withdrawn after the breaking in period.
There are all sorts of anecdotes attached to this but revving an unloaded engine is bad because it places huge additional strain on the conrods and pistons. May seem crazy thing to say but if there is no load on the pistons the conrod has more to do yanking them to a halt at the top and bottom of the stroke, because there is less pressure or resistance, so it stretches and bends the rod more than usual. I know a lad who wrecked a really good Yamaha R6 racing bike engine just blipping the throttle, put a rod right through the side.
The original Austin Seven engine crank only had two bearings, a roller bearing at the front and a double row ball bearing at the back, when #'s 2 and 3 pistons rattled on the head it was time to change up. They very rarely broke the crank... Austin then decided to add a third bearing in the centre of the crank. Those engines didn't rev as well and they broke the cranks, which adds weigh to the argument that if it ain't broke, don't fix it.
As for the pistons and rings, the rings need pressure to cause them to seal, if they are just flapping about in their groove they aren't sealing very well.
My son showed me a video of really good demonstration by James May of ejecting a piston from a slightly slack bore, compared with ejecting a piston from a perfect bore. The difference was significant. They used compressed air and something like a large air gun. It may even be on U-Tube somewhere, in fact that's probably where he found it...
For a normal 'old' road car I don't think there is any need to get too hung up about warming the oil and stuff. We used to heat the oil (Castrol 'R') before we went on rallies in winter but I think it was more of an adventure rather than from necessity. The historic racing lads still do it in cold weather because cold Castrol 'R' is a bit like syrup! Modern multigrade oil is a different thing altogether.
The only other thing I can say is avoid driving up big hills with a cold engine and change the oil regularly.
Ok, finally grasped the science behind this - load lets us open the throttle to increase the charge (and hence pressure in the bores) without over-revving the life out of it. I shall risk running the engine stationary as a morale booster during the build - worst that happens I can get the engine re-honed one winter if it fails to bed in properly. Thanks Ed - been useful.
No probs Marc, glad to share the experiences of my misspent youth! LOL
For what it's worth my Rover V8 engine stood for at least two years with one carb missing and the other open on the dockside in Barrow.
There are watermarks on the bores, but no pitting. I have rebuilt the engine using the same shells and rings. It shows no signs of burning oil, granted very limited test running in garage but you can smell it if it is an oil burner, it doesn't smell. I honed the bores very carefully. Time will tell...
I have occasionally hired 5kva diesel generators single cylinder air cooled hand start Lister Petter or lambardini engines with fixed revs with a load compensator and after about 3 weeks on site they start to rattle and clang and run hot and smell like they are burning oil, the chap from the hire shop comes out puts fresh oil in the air cleaners sump and engine then puts a load bank on them flicks the switches till its drawing near the generators Max load and leaves it like that for an hour or so, the engines labour and after a while kick soot out then they will run fine again for weeks, he says the bores glaze up when they are just running with little power being drawn off, he also said that once they started getting engine oil from a new supplier and all the diesel engines went down in quick succession turns out the new supplier was stickering up a better quality of oil and selling it as a lesser grade, seems simple diesel engines require load and reasonably poor oil to keep things bedded in, if the load bank trick doesn't work he has to strip and hone the bore and manually scrub clean the oil scraper piston ring.Ed
...all the diesel engines went down in quick succession turns out the new supplier was stickering up a better quality of oil and selling it as a lesser grade, seems simple diesel engines require load and reasonably poor oil to keep things bedded in, if the load bank trick doesn't work he has to strip and hone the bore and manually scrub clean the oil scraper piston ring.Ed
I read an article about squeezing the BMW E-30 six cylinder engine into a Marina based Marlin some time in the nineties, and the author recommended 'Happy Shopper' motor oil as the best lubricant for that engine for the same reason. I've got Mobil 1 in my Triumph six at the moment, but I've recently read that modern, high performance lubricants contain detergents and additives that can feck up an old engine, so will be changing it for 'Wilco' 10w 40 (around £9.99 for 5 litres) in a few weeks.
Older engines rely on the fine sediment settling on the bottom of the sump and in nooks and crannies, because the oil filters of the day weren't capable of filtering out the fine particles without clogging.
If you go pre-war (WW2) few engines had oil filters at all. For those engines a basic straight 30 oil is better than even a basic multigrade. I believe that the demand for reliability in the field of war probably prompted the development of oil filtration, which was of course continued post war. 50's and 60's engines had an average 'life expectancy' of from 70 to 100 thousand miles, sometimes much less. I have had several cars in the last 30 years which have gone well beyond 250,000 miles untouched and with no special effort.
Modern oils keep the micro particles in suspension to allow them to be removed by the much more effective modern filters we have today. Another factor is the greatly improved metallurgy; the wearing parts of modern engines are greatly improved both in terms of wear resistance but also in terms of finish, the tolerances in modern engines can be much closer due to CNC machining and improved manufacturing techniques.
So progress re-starts (where does the time go - wife, three kids, house, life...). Anyway, sourced some final bits and bobs for the engine and then looked at ancillaries. Found local places to clean my carb bodies and polish the manifold etc, and sorted out how to upgrade the ignition.
So dismantled the carbs - 30 year old fittings took some persuading, but got there. So this weekend will run the bodies etc down for tidying.
As that was happening I have sorted my workspace to allow me access - so moved ladder to ceiling (DIY job making a roller mount for it - idea from Web) and installed tool walls at side of car so I can mount my car tools in easy reach. All takes time away from spannering as my Stag friend keeps reminding me but I needed the space and can't bear being disorganised.
Long weekend ahead so will clean and repaint engine and components and look to the rebuild. I figure the shiny bits will take a week or so to be ready, so that will work out nicely, with aim to get the engine fired up for the first time in 30 years.
Once that happens (if...) then the chassis can be sorted out again. I have most of the bits so really its a clean and re-paint, and then rebuild the moving bits, before turning my thoughts to the supporting frame, which needs some radical reshaping. But that will be this winter's task no doubt.
Some big bills coming up, but hoping to manage the cash flow so that progress can continue. It has taken me a long time to get back to the car, and no doubt life will get in the way again, but for the summer ahead I hope to throw the hours at it, and see how it goes until the darker evenings kick in and sap my morale again...
The target is to get ready for body work prep for next Spring, so that I can take it outside and reduce the dust and mess in the garage. And hopefully by then my finances will bear the strain again.
Oh, and oils - I went for the running in oil that Paddocks sells. After that, who knows, but the next oil change seems a long way off yet (sadly).
Never been away. I will post some pics once the carb bodies come back and I get the manifold rebuilt.
My problem is I keep looking at Swifty's build over on the Sammio page and he does do VERY nice work on EVERY part, so it tends to make me want to raise my own efforts accordingly. But my car is never going to be as good as his, sadly.
I know what you mean as when i started my Sammio i wanted to take the do everything amazingly approach, but in the end i found just as much personal satisfaction getting things done "as well as i could do them" while learning some new skills along the way.
So when i started my Miglia the plan was to adopt that approach from the outset but then revisit bits and make them even-better over time, while at the same time getting out n about and enjoying the car.
Finally (finally) got some time in the garage that was actually on the car - up to now I have been tidying/sorting the space, getting organised. It paid dividends, being able to just find my tools when I needed them (simple job this weekend, stripping the studs off the block). But sure as eggs is eggs, I managed to just strip the engine block of most of its old crud/paint when I was called back for domestic duty.
Oh well, it's a start. But I worry for my sanity sometimes - if it is taking this long for the simple jobs, how long will the bodywork take me :-)
On a more positive note, the carb bodies came back from the bead blasters looking absolutely fantastic - highly recommend the process. I used a guy in Canvey Island who did a first rate and very economical job. AquaBead Blasting in Canvey - easy to find.
Sadly, the same could not be said for the polishing work, done in Rayleigh. Very poor, unfinished, and expensive. Oh well, live and learn. So the manifold will need more attention from me, my polishing wheel and a drill mop etc. Just wish I didn't have to waste money to get crap results like this. If anyone is interested in avoiding poor work, let me know and I will pass the details on privately.
Oh well, trials and tribulations. Next step is to try and remember how to link photos from my album to this thread.
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