Page 1 of 1
Running in Oil? Engine Rebuilt
Posted: 07 Apr 2009, 11:50
by jgibson808
I have almost completed rebuilding my 1900 DG engine. I'm hoping to start it for the first time this weekend (as long as the rest of the parts I need turn up!)
What oil does anyone suggest to use for the first time? How long to use it for? And what oil should I use after the initial run in?
Anyone got any further suggestion for a rebuilt lump?
Thanks
Jim

Re: Running in Oil? Engine Rebuilt
Posted: 07 Apr 2009, 12:04
by Red Westie
The cheapest crappiest oil you can find (20W/50 or similar non descript) and change it and the oil filter 500-1,000miles for Quantum Blue or Fuchs 15W/40 mineral. Then 5,000mile oil /filter changes thereafter with the same.
Martin
Re: Running in Oil? Engine Rebuilt
Posted: 07 Apr 2009, 17:12
by jamesc76
Crank the engine over with the ht side off to get oil up arounde everywhere, then once dont run it for a about 10 mins then dump the lot filter and all! use tesco value oil or what ever thats cheap then use a good quality oil, and leave that in for 500to 1000 miles then service again no piont spending all that money to scrimp at the last post!
Re: Running in Oil? Engine Rebuilt
Posted: 08 Apr 2009, 09:12
by Red Westie
jamesc76....I think you miss the point! running in oil is all about allowing the engine to wear down those sharp corners, bed in those honed bores and smooth off those new moving parts. The object of and the reason why we use cheap oil is so it doesn't necessarily lubricate that well so allows these moving parts to bed in more quickly and to a better degree.
3 oil changes in under 1,000miles will achieve the exact opposite effect and will delay and prevent the engine from bedding in! if the piston rings for instance, are not allowed to bed in properly you may actually end up with an engine that uses excessive amounts of oil.
Fill with cheapish oil, run to 500-1,000miles then change both oil and filter for better quality.
Martin
Re: Running in Oil? Engine Rebuilt
Posted: 08 Apr 2009, 09:19
by Titus A Duxass
Red Westie wrote:jamesc76....I think you miss the point! running in oil is all about allowing the engine to wear down those sharp corners, bed in those honed bores and smooth off those new moving parts. The object of and the reason why we use cheap oil is so it doesn't necessarily lubricate that well so allows these moving parts to bed in more quickly and to a better degree.
3 oil changes in under 1,000miles will achieve the exact opposite effect and will delay and prevent the engine from bedding in! if the piston rings for instance, are not allowed to bed in properly you may actually end up with an engine that uses excessive amounts of oil.
Cheap oil..1,000miles then change both oil and filter for better quality.
Martin
^^^WHS^^^
Re: Running in Oil? Engine Rebuilt
Posted: 08 Apr 2009, 10:00
by lloyd
I agree with James.
An engine's biggest enemy is particles in the oil that wear things. No matter how careful you are while building the engine, there will be particles in it... plus whatever comes loose when it first starts running. Changing oil after first warm-up/bed in run of 15-20 minutes is good thinking.. and use a reasonable quality oil too as it's cheaper then scoring a bearing for lack of lubrication. A proper rebuild shouldn't require much bed in. Only the rings/cylinders and cam/lifters should need uch bed in/seating in. Main, rod and cam bearing should be polish as should crank, small rod end/wrist pin. Oil pump should have minimum allowed tolerances for best performance. Valves should be seated into seats properly, etc. New rings/cylinders should be pretty well seated within first 30 minutes.. same for cam/lifters. Cylinders need the oil rings to seat enough to stop oil getting past them. If oil rings are doing their job, compression rings will seat fine. I've built more engine then I can count.. many full on race engines. Rings usually seated while turning engine over and setting everything up so well I had to keep spark plugs out to turn engine. I don't agree with cranking over engine to prime oil system as it's not good for the cam/lifter seating. I prefer pumping oil into an oil galley to fill all oil passages so everything is lubricating properly when engine first starts. After it starts it should be run at 2000rpm for about 15 minutes to seat in cam/lifters and cylinder/rings, then change the oil/filter to get any dirt, metal bits, etc. out of system. The first 500-1000 miles should be driven easy to make sure piston/cylinder skirt seat in and piston doesn't scuff/scour cylinder.
Re: Running in Oil? Engine Rebuilt
Posted: 08 Apr 2009, 14:38
by Red Westie
Quote:
An engine's biggest enemy is particles in the oil that wear things. No matter how careful you are while building the engine, there will be particles in it.
And that is why the engine has a filter to catch and retain any particals.
Lloyd and jamesc76, you both obviously have your opinions and I have mine and when reading various articles on the subject there are many different ideas about what is right way.
I know the main VW dealers do it the way I stated because I worked at a main VW dealership for many years....we will agree to disagree on this one.
Martin
Re: Running in Oil? Engine Rebuilt
Posted: 08 Apr 2009, 15:48
by lloyd
Red Westie wrote:Quote:
we will agree to disagree on this one.
Martin
Like you said there are many ideas of what is right, even among professional mechanics.
Re: Running in Oil? Engine Rebuilt
Posted: 12 Apr 2009, 17:46
by jgibson808
Well that makes thing very clear
And I thought it would be such a simple answer!
Thanks

Re: Running in Oil? Engine Rebuilt
Posted: 12 Apr 2009, 18:54
by Red Westie
'And I thought it would be such a simple answer!'
Well it was far as I was concerned

Re: Running in Oil? Engine Rebuilt
Posted: 12 Apr 2009, 19:34
by wasserleaker
I used Comma running in oil, after rebuilding my 2.1, and dumped it, changed the filter after 500miles, then changed the oil and filter as per the normal service intervals in the manual, as advised by a friend who rebuilds engines for a living, so i felt safe to assume he knows what he's talking about! running in oil has no detergents or friction reducing additives, which all, even cheap motor oils have.
2 years and around 14,000 miles later, it's running brilliantly.

Re: Running in Oil? Engine Rebuilt
Posted: 14 Apr 2009, 23:21
by Red Westie
You can still buy it? I haven't seen any proper running in oil for years....Your friend gave good advice although I'm not completely in agreement with his explaination of running in oil : running in oil has no detergents or friction reducing additives.
1) Detergent not only cleans but acts to suspend particals so they are transported to and filtered through the oil filter. Lack of or poor detergent leads to sludge build up which can block oil ways and galleries.
2) No friction reducing additives! hells bells your engine would seize up in a matter of minutes without it!
Martin
Re: Running in Oil? Engine Rebuilt
Posted: 15 Apr 2009, 17:30
by wasserleaker
From what i've read about running in oil, RedWestie, it's basically just a plain mineral oil, which adequately lubricates the moving parts, but doesn't contain all the additives found in 'ordinary' engine oil, as it's just there to allow the high/tight spots to wear in, though you're prob right about it containing
some additives, but a lot less than your average motor oil, as its not in there long enough to need them. just going on what i've been told and what i read when looking into it, a while back.
several companies do still make it, a good motor factors should sell it.
Also, if a new cam and lifters were fitted, it's important not to let the engine idle, but to keep the revs up around 2500 for the 1st 15 mins or so of a newly rebuilt engines running in time.
cams are under most load when running at idling speeds, just google 'bedding in a camshaft' if you don't believe that, as last time i mentioned it on a similar thread, the know it all masses who just regurgitate what they have read on here, but don't really know a deal from experience. poo poo'd the suggestion.
just trying to pass on what i have learned from people who have rebuilt more engines in a fortnight than i ever will in a lifetime! i tend to pay more attention to peoples advice when it comes from actual experience, rather than just their opinion.
