Section : Engine

Engine, cooling system, fuel system, exhaust system.

Sick symptoms: discuss

Posted By : Donald Robinson, 05-Sep-2006, 10:54pm

Oh dear. I took her out for a run a couple of days ago. I'm running octane booster but I was still getting a little bit of pinking under full load. All seemed well for 20 miles using up to 4500rpm but then I accelerated away from a junction and as I eased off I lost a cylinder. I've nursed her home but the cylinder doesn't seem to have come back at all.
It doesn't fire on one at any time and doesn't tick over - no backfires or anything like that. I've checked the points so far, I opened them a little but no change. There are also no other symptoms, oil and water seem separate and aren't getting out, there is no smoke or warning lights and she runs a little cooler than normal.
Any suggestions before I start major surgery? My thoughts were possible duff plug (please God, although they are only 500m old), otherwise broken valve / seat / rocker or maybe holed piston but there doesn't seem to be any pressurisation. Help!! (and thanks)

Followups :

Sick symptoms: discuss

Posted By : Leon Guyot, 06-Sep-2006, 05:50am

Donald,

Plugs CAN go bad after only 500 miles, but I suggest that you do a compression test before proceeding with any strip down of engine, or spending money.

Compression tests can be very informative.

Good Luck

LÃ©on
Sick symptoms: discuss

Posted By : Jonathan Binnington, 06-Sep-2006, 06:24am

Donald, check it out systematically, you will find the answers yourself

j
- Sick symptoms: discuss
  
  Posted By : Steve Cureton, 06-Sep-2006, 08:49am
  
  Are you using Champion spark plugs? If so bin them ASAP.
  - Sick symptoms: discuss
    
    Posted By : Donald Robinson, 06-Sep-2006, 09:55am
    
    They are NGKs. I'm going to get a new set and do a compression test when I fit them. Hopefully get at it tonight. Watch this space!
    - Sick symptoms: discuss
      
      Posted By : Paul Bodiam, 06-Sep-2006, 01:03pm
      
      Hi Donald
      
      Have you determined which cylinder is not firing?
      with the help of an assistant, disconnect one spark lead at a time ad run the engine. Most of the time this will make the symptoms worse, until you disconnect the spark lead on the bad cylinder in which case the symptoms will remain the same.
      
      Once you have identified the problem cylinder, remove the spak plug and examine it. Has the gap changed? Swap this plug with the one from an adjacent cylinder. Does the fault move to the next cylinder (problem is in the plug) or does it stay on the same cylinder?
      If the fault stayed on the same cylinder, swap the spark lead with another (remember to swap the lead at the plug as well as at the distrutor cap. Again, does the fault migrate to another cylinder (spark lead is at fault) or does it stay put?
      
      Now get a compression tester.....
      
      hope this helps
      Paul
      - Sick symptoms: discuss
        
        Posted By : Peter & Mick (son) Lewis, 19-Sep-2006, 06:42pm
        
        no smoke stick to the cheap options, dont forget to check the carb spindles both open/ loose connector etc. and distributor spindle side float due to worn top bush
        stick to basics before entering the deep pocket repairs peter