Register now to get rid of these ads!

Technical Leak down percentage on 216

Discussion in 'The Hokey Ass Message Board' started by 1950fleetline, Nov 13, 2017.

  1. 1950fleetline
    Joined: Jun 1, 2017
    Posts: 70

    1950fleetline

    did a compression test on my 216, getting 100 psi on cylinders 1-2-4-5-6 gett 95 psi on cylinder 3
    Did a leak down test and getting around 30 percent on all cylinders, can hear air from the dip stick tube
    I'm thinking it may be time for pistons rings? Before I start tearing into it, I figured I'd get some input for you guys.
    Any advice greatly appreciated,
    Thanks!
     
  2. reverb2000
    Joined: Apr 17, 2005
    Posts: 441

    reverb2000
    Member
    from Houston TX

    216 isn't the best engine. If it runs just keep running it. If you like the straight 6, get a 235. They are very cheap or free.

    Sent from my HTC One M9 using The H.A.M.B. mobile app
     
  3. 302GMC
    Joined: Dec 15, 2005
    Posts: 7,874

    302GMC
    Member
    from Idaho

    If you have a 216 Chev with decent compression on all 6 holes, don't mess with it unless it uses too much oil to suit you.
    If you do open it up, first check a few rods & mains for acid etching. If none found, ridge ream & find how much taper it has. If under .015, do the old days OH - rings, adjust the bearings, & grind the valves. If it needs more, later sixes to '62 "bolt in", and so do GMCs ...
     
  4. squirrel
    Joined: Sep 23, 2004
    Posts: 56,085

    squirrel
    Member

    How much oil does it use?
     

  5. 1950fleetline
    Joined: Jun 1, 2017
    Posts: 70

    1950fleetline

    I've heard that a lot, maybe I would be further ahead with a 235 since it's a better engine.
    My 216 runs good., just smokes a little and uses A LOT of oil, thanks for the reply!
     
  6. 1950fleetline
    Joined: Jun 1, 2017
    Posts: 70

    1950fleetline

    It uses a crazy amount of oil, I've used a quart within a 70 miles easy! It doesn't smoke nearly as mush as I would think for using so much oil and engine fires right up and sounds good.
    I was told by the previous owner that the engine had been rebuilt but sat sat for several years after, I was kinda hoping the rings just hadn't seated yet but I'm starting to think otherwise.
    Thought about trying umbrella valve seals to see if it helps?
    Thanks for the reply!
     
  7. 1950fleetline
    Joined: Jun 1, 2017
    Posts: 70

    1950fleetline

    It does use a lot of oil but the compression doesn't seem too bad considering 110 psi is what the manual says and I'm getting around 100, if I could just the oil consumption down I'd be happy.
    Thanks for the reply!
     
  8. squirrel
    Joined: Sep 23, 2004
    Posts: 56,085

    squirrel
    Member

    I'd probably see about doing a ring job on it...like 302 suggested.

    That's a lot of oil!
     
  9. Atwater Mike
    Joined: May 31, 2002
    Posts: 11,624

    Atwater Mike
    Member

    ...or some Bon Ami thru the carb air horn at a fast idle...Mentor Red Mayfield saved a few as I watched. (rings hadn't seated, so he 'honed 'em in')...It worked.
     
    tractorguy likes this.
  10. Check for big leaks first? The side covers on these leak like a seive after a few years. When its "check the gas, fill up the oil" time, it's a signal to start looking for a later 235. (They used 235 ci engines in trucks which were 'dipper ' type so don't just go by the capacity when looking for new mill). When you start up, is there a cloud f smoke which clears up after a few seconds? Could be some valve seal/stem problem.
     
  11. 302GMC
    Joined: Dec 15, 2005
    Posts: 7,874

    302GMC
    Member
    from Idaho

    I've had 216s that dripped oil out of the tailpipes when they idled. Did somebody do the head without ringing it ? That immediately breaks any ring seal left in a worn engine
     
  12. 1950fleetline
    Joined: Jun 1, 2017
    Posts: 70

    1950fleetline

    seems like sometimes its smokes at startup then clears up and other times its constant, at one point the plugs started to even look better almost like it was starting to use less oil.
    did another leak down test today with the engine cold and it was reading about 40% on all cylinders, been keeping my eyes out for a later 235, theres a guy that has one around me out of a 1957 chevy but he kinda wants a lot for it
     
  13. 1950fleetline
    Joined: Jun 1, 2017
    Posts: 70

    1950fleetline

    its possible, the previous owner said the engine has been rebuilt but sat for years after but who knows?
    with the amount of oil I'm using it almost seems like its the rings , definitely gonna have to fix it over the winter, adding oil almost every time i go for a cruise is getting old!l lol
     
  14. squirrel
    Joined: Sep 23, 2004
    Posts: 56,085

    squirrel
    Member

    To get the full old time feel of fixing it, you ought to do an "in the car" ring job on it...

    Gaskets and rings cost well under $150 at rock auto.
     
    tractorguy and Moriarity like this.
  15. 1950fleetline
    Joined: Jun 1, 2017
    Posts: 70

    1950fleetline

    good point, I already have a head gasket kit in the box just need rings and oil pan gasket, honestly i actually enjoy working on this thing. I'm doing rings
    Thanks Squirrel
     
    302GMC likes this.
  16. Try doing a dry and wet compression test and leak down

    If the numbers go up on the wet tests good indication rings are the issue

    If they don't go up it's the valves

    On the older 216's the umbrella seals on the valves ...... the verdict is still out some say yes , most say no as they seal to well and cause valve issues replacing the o rings is enough


    If your thinking of swapping engines anyways why not fill it with some lukas oil additive and run it ?
     

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.