Compression test results

1. Mickswan Saxperience Forum Bum Joined: Apr 2013 Jarrow Posts: 4022 2003 Icelandic Grey 16v VTR 1991 Daihatsu GTti

   #1 11th July 2014, 16:24

   Ok, just done a comp test on the VTS and each cylinder was at 100psi, I'm thinking that's low so I popped a little oil in each cylinder and again 100psi so I'm thinking the rings are ok.
   
   I'm not too sure on the gauge as it's old so it could be out (going to try another this weekend).
   
   I'm going to do the head gasket soon anyway but I'm wondering if there's anything totally obvious I've missed.
2. Ali123 Saxperience Forum Bum Joined: May 2011 huddersfield Posts: 2635 ph3'd c2 gt

   #2 11th July 2014, 16:33

   that does seen rather low tbh, when I did a compression test on my 16v it is/was on 120kish and made 165-170 across all 4 !
3. chompy Established Member Joined: Jan 2008 Scotland Posts: 1764 Because racecar

   #3 11th July 2014, 16:39

   low comp pistons/decomp plate by any chance?
4. D4MJT Saxperience Forum Bum Joined: Mar 2009 Morpeth Posts: 2539 BMW 116d Regional Toner Sales Edition

   #4 11th July 2014, 16:46

   Either that, and I could well be talking out of my arse here, why break the habit of a lifetime, but if you've got low compression on all cylinders, and a bit of oil makes no difference, does it not point to fucked valve seals?
   
   100psi sounds low to me. As previously stated though, I'm a fucking idiot and even I don't listen to myself.
5. Mickswan Saxperience Forum Bum Joined: Apr 2013 Jarrow Posts: 4022 2003 Icelandic Grey 16v VTR 1991 Daihatsu GTti

   #5 11th July 2014, 16:51

   As far as I'm aware its totally standard (apart from a sportex back box), I bought it as an mot failure for £300 as there's a shit load of rust. Engines on just over 100k, I've only bought it for a conversion.
   
   Just wanted to make sure I didn't need to do the rings before I threw it in the R. As said I'll be doing the head gasket and valve seals etc etc
   
   Also I'll try another gauge see what result that throws up.
6. Mickswan Saxperience Forum Bum Joined: Apr 2013 Jarrow Posts: 4022 2003 Icelandic Grey 16v VTR 1991 Daihatsu GTti

   #6 14th July 2014, 10:20

   Crisis avoided, knackered gauge.

   3 users thanked this post: chompy, D4MJT, Ali123
7. Ali123 Saxperience Forum Bum Joined: May 2011 huddersfield Posts: 2635 ph3'd c2 gt

   #7 14th July 2014, 10:47

   Bet that was a relief haha!
8. Mickswan Saxperience Forum Bum Joined: Apr 2013 Jarrow Posts: 4022 2003 Icelandic Grey 16v VTR 1991 Daihatsu GTti

   #8 14th July 2014, 11:50

   Quote:

   Originally Posted by Ali123 Bet that was a relief haha!

   Too right!
9. MartinObviously Saxperience Forum Bum Joined: Dec 2012 Perth Posts: 3665 Peugeot 106 1.1 Turbo Peugeot 106 1.5D Turbo Peuge

   #9 14th July 2014, 12:13

   Well that's a bonus!
   
   I was gonna suggest a leakdown test for checking valves
   
   Would be odd to have such low compression without it running like shit/no power.
10. Mickswan Saxperience Forum Bum Joined: Apr 2013 Jarrow Posts: 4022 2003 Icelandic Grey 16v VTR 1991 Daihatsu GTti

    #10 14th July 2014, 12:54

    Quote:

    Originally Posted by MartinObviously Well that's a bonus! I was gonna suggest a leakdown test for checking valves Would be odd to have such low compression without it running like shit/no power.

    To be fair martin I've drove it once for 3 miles and it's stood on the drive ever since. Thought I'd best do the test before I took the head off then built it back up to find it need to do the rings after all.

    1 user thanked this post: MartinObviously