GO FISHING, use SLABSAUCE Fishing Attractant
Results 1 to 3 of 3

Thread: Engine basics - Compression and stuff

  1. #1
    Join Date
    Dec 2003
    Location
    Eastern Tennessee USi
    Posts
    14,839

    Default Engine basics - Compression and stuff

    Working on a Hondud 4 cylinder. Thing ran great except anytime you revved it up it would shower antifreeze anywhere it could escape. No other issues, no smoke over heating etc. Smooth idle etc.

    So we pulled the head as it seemed to be some sort of head or head gasket leak and yes it was. Just a little burn through the head gasket about 1/8 inch or about 3-4mm around the cylinder sealing part. Head and block look good, no burn or heat marks, looked flat with nothing unusual. The gasket itself took a fair amount of time to actually find a fault.

    Replaced gasket, sprayed with copper stuff incase we missed a problem and good to go. Used old bolts, not a good thing I know but did anyways. Ordered new bolts for later. Car ran great, got 20.10 MPG no burning oil, no antifreeze shower etc. THEN a few days after that we started getting a slight miss at idle when hot. Uh-ohh. Miss got worse and eventually got a code that said #4 has random missfire.

    Checked basics, valve lash cap, rotor, wires and found 1 wire not quite into the cap and oxidation. All plugs sparked tho. so WTF?

    Compression test time....
    1=135
    2=120
    3=85
    4=80

    Okay looks like a leak between 3 & 4 so time to add oil for another check...
    1=135
    2=125
    3=120
    4=90

    Okay anther WTF moment. #4 is gimp.

    Try to start, no spark. Another distributor and it started right up. (never do a compression test without disconnecting power to distributor)

    Built a leakdown tester and ready to test but want to fire it with valve cover off to make sure rockers are all moving right. Whoaaa lots of oil dumping around the rockers, like a LOT! Where the oil is trying to pour back through the head its just fountaining back up and over the entire garage. Still a big miss. Must be a bad piston/ring or something, time for leakdown test results.

    This sucks.

    Leakdown results to follow.
    95 E34 530I V2.37
    ===========
    Those who make peaceful revolution impossible will make violent revolution inevitable.

    John F. Kennedy

  2. #2
    Join Date
    Feb 2006
    Location
    Oldham, England
    Posts
    3,078

    Default

    Which engine? The 1.6 16V SOHC? If so, I've had a couple and its a cracking little motor. I think one of my sons boiled one dry and it blew the HG. When you cranked with a plug out, it spat water at you I had a cam belt go doing 70mph and no damage apart from a new belt. One stood for 6 months and the rings stuck in the guides. I spoke to an engineering shop and the guy told me the bores are pretty solid and dont wear much and I should just hone them. I put in new rings and valve guides oil seals. Ran like a dream for years after. Oil pump gives 20 psi at idle. Compression pressure is a min of 150 psi with max 20 psi difference between the cylinders.
    I've just put the workshop manual in the bin so if you need any info give me a shout before tomorrow as thats when it gets emptied
    Last edited by whiskychaser; 11-24-2011 at 06:07 AM.
    Oct '00 E46 330i. Feb '92 525i (departed)

  3. #3
    Join Date
    Dec 2003
    Location
    Eastern Tennessee USi
    Posts
    14,839

    Default

    Yes 1996 1.6. Manual sounds good! PM me and I can paypal shipping?

    Leakdown results:
    1=68%
    2=50%
    3=65%
    4=90%

    all blowing strong through exhaust valves. Going to pull them now and see whats the deal. Lots of play in the guides so they are either bent or?

    Happy Thanksgiving all!
    95 E34 530I V2.37
    ===========
    Those who make peaceful revolution impossible will make violent revolution inevitable.

    John F. Kennedy

Similar Threads

  1. MOTRONIC 1.1 and 1.3 basics functions explained
    By shogun in forum 5 Series BMW
    Replies: 0
    Last Post: 06-03-2008, 10:27 AM
  2. Basics of Troubleshooting
    By shogun in forum 5 Series BMW
    Replies: 0
    Last Post: 04-25-2008, 09:40 PM
  3. checking engine compression - DIY
    By shogun in forum 5 Series BMW
    Replies: 3
    Last Post: 08-03-2006, 05:53 PM
  4. Cosmoline, the yellow stuff on your engine
    By shogun in forum 5 Series BMW
    Replies: 11
    Last Post: 11-15-2005, 01:11 PM
  5. Conducting Engine Compression test
    By jj7 in forum 5 Series BMW
    Replies: 2
    Last Post: 05-01-2005, 04:23 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •