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Running old engine

  1. Apr 2, 2006 #1

    wolram

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    Can anyone tell me if an old engine (50 years old) will run ok with modern
    multi grade oils, and unleaded petrol (without major modifications)?
     
  2. jcsd
  3. Apr 2, 2006 #2
    I'm not sure, but synthetic should fill in the abrasions. I'd worry about leakage too. What are the rest of the fluids like?
     
  4. Apr 2, 2006 #3

    wolram

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    Vincent, (good name), i am talking about running vintage engines in general,
    multi grade oils were not around when they were made, and wondered if
    using them will in any way be detrimental, i have been looking on the net with no luck as yet, i am sure the guys that run vintage vehicles could tell me, but i can not find one of them to talk to.
     
  5. Apr 2, 2006 #4
  6. Apr 2, 2006 #5

    Cliff_J

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    You can still purchase straight grade oils as well. You should be ok running a modern oil with a similar base viscosity, a 10W-40 will have the viscosity of a 10W oil and has additives to offer the protection of a 40W oil when warm.

    I would not suggest a synthetic, my experience and some ancedotes revolve around it allowing an engine that did not have an noticeable oil use to begin consuming far more oil on those expensive synthetics. Some brands behave better, some are not so great. I didn't care for the recommended synthetic ATF in my T56 manual, it seemed to stick on shifts much more after only a few hundred miles, problem went away after switching back. If I were to purchase a Z06 or some other car that came recommended to use Mobil One, I would to avoid warranty issues with potential deposits or lack of film protection under hard use, but would also assume that the engine was engineered and tested for proper operation with that oil.

    The gasoline is another story, 50 years is right around the time of leaded gas additives and many motors from even the late 60s need the addition of hardened valve seats in order to not allow the valves to damage the valve seats. The more a high performance motor with high compression and especially aluminum cylinder heads, the more likely you'll want to research what fuels and/or additives are safe. You can still purchase the leaded fuel for off-road use and marine use, no idea where though.

    You can find a ton more info with a google search of something like "leaded fuel replacement"

    The manner of operation matters too, if you're just out for a Sunday cruise its not going to be as hard on anything as a race around a road course with lots of wide open throttle.

    For curiousity, what car engine? An old Fireball 8 or a Stude or what? :smile:
     
  7. Apr 2, 2006 #6

    wolram

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    Cliff, it is a 1960s velocette motorbike.
     
  8. Apr 3, 2006 #7

    brewnog

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    Wolram, if you're going to be doing any miles, I'd consider having hardened valve seats fitted. Only some additives are ok, and LRP definitely isn't. For a nice old engine like that I'd do it properly.
     
  9. Apr 3, 2006 #8

    wolram

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    Hi, brewy, ive not done this before, or even thought of the lack of lead in
    petrol, i do want to use the bike, so i have to do things proper, does it only
    require valve seat hardening, what about ignition timming, fuel mixture
    etc ?
     
  10. Apr 3, 2006 #9

    Cliff_J

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    wolram - there's a ton of data out there on the internet for those motorcycles, I'm sure you could contact a person in one of the clubs and get all the required information needed if you wanted to remove the cylinder head and have the hardened seats fitted at a proper machine shop.

    As far as the ignition and fuel mixture, that should still be just fine if within factory specificiations. If the carberator hasn't been at least cleaned or fitted with an overhaul kit, that would be a good idea to ensure its operation is proper as well, no reason to ruin a good engine because a float bowl was adjusted too low or a jet was full of debris and caused it to run lean. A new set of points isn't a bad idea as well, assuming its easy to set the dwell (but that might be set via just the gap).
     
  11. Apr 4, 2006 #10

    wolram

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    Thanks cliff, i have found the (owners) club, dumb or what ? i should have
    searched for that in the first place, now i have a source of info (and) spare
    parts, whopeee.
     
  12. Apr 5, 2006 #11

    Danger

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    Another thing to consider about unleaded, Woolie, is that it's pretty low octane compared to the old stuff. If your compression ratio is more than maybe 8:1, you might need to add octane boost supplements and/or retard your ignition timing to prevent detonation (AKA pre-ignition or 'pinging'). My Roadrunner has 12.5:1, and it absolutely won't run on anything that you can buy outside of an airport.
     
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