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What Volvo engine are you building. That clearance is mighty small. Running in oil is often used to ensure the rings bed in well and do not polish the bores which can lead to ring tip overheating and higher oil consumption. I do not use fully synthetic oil until 2000 miles, running in oil or a decent 10/40 for 500 miles, new filter and a Semi Magnatec and no additives then a complete change and filter at 2k and either magnatec or mobil one if the engine and the performance demands that. I service all my cars at 6k 10 and 12k sevices I do not like. Regards Peter
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Its a B200E from a 1986 360. The clearances are as specified in the Volvo official green book.
Incidentally, I wasn't happy with the look of the intermediate shaft bearing shells, so I bought some new ones, but the machine shop has just rung and told me that they're unfinished bearings and need boring to the right size. An extra 110 quid, probably caused by me scratching the bearings as I pulled the shaft out. Oops!
Moral: be more careful Andrew!
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I don't think the running in technique can be as critical as all that. Just don't do anything excessive. The traditional Volvo engines are immensely robust and commonly last hundreds of thousands of miles, and I don't believe they ever got especially kid-glove treatment from their first owners.
The only amazing thing is that you have managed to wear yours out!
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Hello.
You say those clearances are too tight but does that explain why they last so long. Just use the correct oil from the start and dont thrash it.
--
(iam not a mechanic)
Martin Winters
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also surprised you managed to wear it out.it would be interesting to know what mileage had it done before the rebuild ,as cliff said they mostly last hundreds of thousands of miles and indeed our old 740 (also b200 engine)at 250k miles was still at its best when it got written off despite only getting an oil change every 20/25k if anyone remembered to do it or if it looked very black on the dipstick.I wouldnt be too fussy about the running in ,how many people actualy run in a new car which is the same thing .
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It had done 124,000. I don't think it was 'worn out' as such. All the bearings, big ends, mains etc are well within spec, as are the valve seats and valve guides, all they needed was a bit of lapping paste.
The trouble was the 'piston slap' problem which seems to plague all these Volvo redblocks from a certain era. They modified the design in 1993 to increase piston cooling and stop this, but I just thought, lets strip it down and the pistons were indeed worn out. Unfortunately the piston slap had ovalled the bores too, so a rebore was the way forward.
Incidentally, I've got a scrap motor from a low miler (85,000) in the car at the moment whilst I'm rebuilding the original one, that has piston slap on a cold morning too. Never let it get to the stage where it burnt oil or used it to a great amount though.
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I've seen plenty of B200 that are well worn at 150k miles. usually they are breathing heavy (i.e. take off the oil filler cap, rev the engine and you see the crankcase fumes blowing out).
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I used to work with a chap who was in the dessert with Monti in the 2nd world war. His job was sorting out and re-building battle worn and damaged tanks. After an engine re-build, the tank driver was told to take it easy until the engine was run in. The tank commander, quite rightly, used to point out that running an engine in gently whist dodging shot and shell was unrealistic, and was there anything which could be done to speed up the process. He, and his collegues used to then remove the air filter, give the engine a few revs, and drop a dollop of Brasso straight into the carburettor! According to him, you could hear the revs rise, and the tank was then ready to dodge shot and shell!
An interesting tale, but I don't think I would try the same thing!
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I'm told that this was one of the tricks Colin Chapman used in his early Lotus days when he was racing. He'd build a back axle up, dump some parrafin & brasso into it, run it for a few miles & then drain it out & flush with new oil! Meant minimum friction.
Jim
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When I lived in Felixstowe (early 80s) I used to the see the volvo delivery drivers take the new cars 12 miles up the road to Ipswich. They didn't bother to restrict either revs or speed that I saw!!!! If those new cars were to the same tolerances as yours then they seem to be OK with a bit of early abuse.
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That's interesting. Erm, the trouble is I THINK that the OEMs run their engines up through a prescribed break in procedure on the dyno don't they?
I've got to try and mimic that on the road. Would love to know what the procedures are.
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Whatever the OEMs do is, for your situation, alas, irrelevant.
Running in is akin to final machining process, and can allow parts to run and seal together in a way which would be very expensive to produce on the cutting machines alone.
While you have had your engine machined so that the macro-measures are acceptable, like bore diameter, ovality, etc, the detail of the surface finish will almost certainly be different to that in a new engine.
Some OEM bores, for example, are expensively plateau honed, in order to give a surface which seals well, and carries an appropriate volume of oil for lubrication. Aftermarket bores, while undoubtedly having an acceptable roughness average value, do not usually have the plateau honed features. Running in, effectively converts the as machined surface finish to one which more closely resembles the plateau honed finish, by knocking the tops off the most proud asperities.
My suggestion is to run it about, avoiding labouring, on cheap oil for a thousand miles or so, then flush out, change the filter, and fill up with decent quality oil thereafter.
number_cruncher
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Thanks, NC, I've got Comma 'Running in Oil' I just wish it had some sort of spec on the bottle, it doesn't even give you a viscosity.
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