If you've ever cleaned the insides of an old engine, you'd realise it can't be done with another oil. You get a build up of burnt on deposits that take some shifting. But actually don't do any harm, provided the oil has been changed correctly and on time.
In one.
Indeed, that has always been my philosophy and was the advice from my trusted mechanic when I mentioned flushing to him some years back out of curiosity.
I've wondered about the 'draining' of oil by sucking it out of the dipstick tube. Doesn't seem like a good idea to me.
Short of stripping an engine down, you can't get rid of all old oil by draining it anyway. If a car is serviced properly, the oil is changed long before it degrades to any significant degree. That can be proved by having it tested.
I must admit, we rarely do the number of miles specified for a service these days- the services are done on time- so that is certainly true on our case.
Having said that, I know someone who insists he never changes his oil, just tops it up. Last time I saw him, he had one VERY old vehicle (a diesel) which was still going, although not used every day.
I think he tended to change his other vehicles every few years, and they tended to be bought s/h.
Ok. What-if ... you drained your oil, added a flushing oil (and assuming it had greater solvent abilities than a straight oil), ran it up for a while, drained again and got out more dirty oil than was just left over from the initial drain?
But it's not about 'flushing' that sort of thing is it? It's supposed to move more old oil and sludge than a conventional oil (change) would?
Cheers, T i m
p.s. A motorbike I was working on for daughters friend recently leaked some petrol into the sump. It was run (slowly) with this very mild petrol to oil mix ... so do you think this 'oil' would have flushed any gunge out or not?
Sounds risky- I heard of a crank case exploding many years ago. Story was petrol vapour after petrol had been added to the crank case.
How/why it ignited - dunno, perhaps a bad ring? I always assumed it was a 4 stroke but, if it was a 2 stroke, perhaps it ran backwards- would that blow exhaust into the crank case?
petrol 2 strokes always have atomized petrol in the crankcase while they run, it is how they work.
petrol 2 strokes can run backwards without too much difficulty, the exhaust still goes out of the exhaust port.
I guess that could be a risk, depending on the resultant fuel / air ratio etc and some ignition source?
That's about the only ignition source path I could think of.
As MrC has answered, I hope not. My Messerschmitt KR200 has two sets of points so you actually run the engine backwards for reverse. ;-)
But anyway, that wasn't the point, it was if an oil was added that contained percentage of solvent, wouldn't that be 'more likely' to shift some of the sludge than just straight engine oil?
What if you filled the (hot) engine up with paraffin (oil) or diesel and just cranked it over and leave it over night? [1]
If you tip some petrol into a jam jar that contains the residue of some old oily thing, it does seem to dissolve it and make the sludge more mobile.
I'm not recommending anyone try any of the above of course ... just asking ... ;-)
Cheers, T i m
[1] I can't see there being an issue as long as any dislocated sludge fully 'dissolves' (in suspension) into the solvent / oil and then makes it to the oil filter.Some bikes have a 'centrifugal filter' where the sludge gets trapped in little pockets (often in the clutch from memory).
I have read that the magnetic sump plugs can be an issue if a 'clump' of magnetised particles break free and end up in an oil way etc. ;-(
I think you may have far bigger worries if you are collecting that much metal between services. ;-(
Can you guarantee the sump plug is actually removed in a service?
Many oil changes are where the oil is sucked up through the dipstick holder.
Indeed, wasn't that how "reverse gear" operated in some of the 50's bubble cars and the like. Maybe the original Bond three wheeler too (before the Bug).
I'm sure I was told that at the time, the excise duty on bike was cheaper, and a bike must have less than 4 wheels and no reverse gear! Hence the necessity to start an engine backwards for the smaller but heavier 3-wheelers.
Yes, I know but it is 'cold' and not the 'normal' petrol you'd expect- at least as I understood the story. I was thinking that it somehow mixed with hot gases from a burn phase which caused it to ignite. I was trying to think how it ignited in the crank case.
I suppose it must, especially as the fuel/air must enter as normal or it wouldn't run. That blows that idea out of the water ;-)
I always fancied a KG200!
Damage to oil seals?
I fitted a magnetic sump plug to a MK2 escort, a car I did quite a lot of miles in really. It never seemed to collect anything magnetic, just the normal, light, gunge that washed off as the oil ran over it.
Oh, sorry, I forgot this wasn't the d-i-y group. ;-)
I would have far bigger worries if I found loads of metal filings on a magnetic sump plug between my servicing ... ;-)
Not here they aren't.
Typically I try to do it after we have used the vehicle and whilst the engine is still warm. On most you can do it whilst the engine is still hot, except for the Transit Connects where the oil filter is up the back of the engine and you have to fiddle it out over the steering rack ... (with the risk of tipping hot oil down your sleeve ...). ;-(
Cheers, T i m
p.s. The last vehicle job I did was Friday, helping daughter service the rear brake caliper on her Suzuki 600 Bandit. The job was easy enough, or would it been had the pad retaining pins not been seized into the body of the caliper and on one side they went into blind holes. That meant you couldn't simply punch them through and so we had to cut them off near to the outer end with the Dremel, split the caliper, punch the two short bits through one side of the caliper and heat, Plus Gas, Mole grips, heat, Plus Gas, Mole grips until we could extract them without damaging the caliper body.
Assuming the holes wouldn't intercept an oil gallery, what would stop us drilling them right through, making it easier for us next time (and I could punch out some rubber bungs to cap them off in between etc)?
Was that a Special Unit?
I bought my KR200 when I was at college as a cheap form of covered transport.
I wouldn't want to be buying one now days (and will sell you mine if you are interested). ;-)
I'm not sure? Given the outside of many engine / gearbox seals could be exposed to contamination from the likes of petrol or other chemicals (engine cleaners, brake / clutch fluids, antifreeze, screen wash etc), I would have hoped they would be able to deal with them all equally (especially over short term exposure)?
Well, that's the ideal outcome of course but short of checking your oil more closely (or getting it sent off for analysis etc), an excess of metallic powder or even particles on yer sump plug do offer a fairly quick and easy indication of the state of the engine (/ & gearbox if combined).
Cheers, T i m
It is but many here seem to chairbound to service their own car.
Agreed, I don't think mine has a magnet.
Likewise, but I was thinking of a typical garage service.
If these are the pins I think they are, I have always seen a through hole.
Machining a through hole makes sense too as it reduces a variable in production. Perhaps lots of grease in the hole?
No, finger trouble.
Thanks but my days of riding in uncomfortable vehicles are over ;-)
May be.
Oh, I'm not suggesting they aren't a good idea. Just commenting on my limited experience of using one.
A modern engine may have parts internal that may react adversely to a non-recomended oil additive. For instance, the timing belt on my Ford 1L engine runs in the oil.
;-)
I'm not sure many do from the factory but I tend to obtain and fit one wherever possible.
I know ...
Same here.
I'm not sure why they didn't in this case, other than it's at the bottom of the disk in amongst all the muck and bullets so maybe they thought it would *resist* the ingress of water and then corrosion?
Another reason might be that to retain the pins they just used a linked / double 'R' clip that does both pins but only acts to stop the pins moving outwards. So one solution would be to only drill a hole small enough to allow a fine pin punch but not as big a diameter as the pad pin itself (it could also be off centre).
Looks like it's not an unknown problem and drilling though a known solution:
We put some Copaslip in when we re-assembled it and will do so again if we mod it when putting some new pins and seals in when we order some in.
Cheers, T i m
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