QuestionQUESTION: John i have a knocking sound coming from cylinder 7 .i found that by disconnecting the plug the noise stops.i pulled the sump off and visually inspected the big end bearing and it looks ok.i have plastigauge what is the max clearance allowed?
what else can it be?Can i replace only one bearing if needed.by the way it is not a loose liner as i had them all replaced by tophat liners a couple of years ago.
ANSWER: The knock is more likely to be a loose piston. The rod clearance has to be low, 1-2 thousandths but that is never the problem unless the berings is actually melted.
The skirts collapse by 5-10 thousandths and then the pistons rattle. I have seen that several times before
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QUESTION: John,Can i re-use the head bolts more than once?
Can the head be removed without taking the motor out,the last bolt seams hard to get to.'against the firewall'
can the bolts be replaced with ones that can be torqued by wrench rather than torqued and then 90 degrees?
Thanks for your help Rob.
AnswerThe head bolts tend to snap if you try and re-use them. I advise against that from personal experience. The heads certainly come off with the engine in the vehicle. I know one bolt is in the corner back there but we use an allen socket and 1/2 inch drive breaker bar adn take it right off. The "torque to yield" bolts have replaced "torque to a number" on most high performance engines. LR is not alone in using them.
Good luck with it,
John
Check my car blog at http://robisonservice.blogspot.com My regular blog is http://jerobison.blogspot.com and I'm also on Facebook and @johnrobison on Twitter
