Help sought with problem Volvo Penta MD1B........ A month or so ago we were running it at slightly higher than normal revs and it began an occasional metallic clatter..... not continuous, maybe every 5 seconds or so, sometimes the noise came in groups of two or three, a single metallic 'clink'
Within a minute the engine had stopped..... not suddenly, just ran down to zero revs. There was no compression, it could be turned over easily by hand.
We got a tow back from the HM and later removed the head. The gasket was blown, the copper from the sandwich was shredded and a little bit was stuck under the inlet valve, hence no compression.
Gasket replaced after thorough cleaning, other components appeared undamaged. On reassembly engine started fine after bleeding and ran well, for about fifteen hours albeit at lowish revs. Now the 'tinkling' noise has returned, but only when run at slightly higher revs. Any ideas? Is it about to blow another gasket? What could be making the noise?
Last week, hard astern, the engine again made the 'plinking' sound and after a few seconds partially died, revs to almost zero, then picked up again and returned to normal (I throttled back a bit).
Could it be sticky valve? Is it interference valve/piston.. maybe noise is valve being struck by piston?
Andy
Within a minute the engine had stopped..... not suddenly, just ran down to zero revs. There was no compression, it could be turned over easily by hand.
We got a tow back from the HM and later removed the head. The gasket was blown, the copper from the sandwich was shredded and a little bit was stuck under the inlet valve, hence no compression.
Gasket replaced after thorough cleaning, other components appeared undamaged. On reassembly engine started fine after bleeding and ran well, for about fifteen hours albeit at lowish revs. Now the 'tinkling' noise has returned, but only when run at slightly higher revs. Any ideas? Is it about to blow another gasket? What could be making the noise?
Last week, hard astern, the engine again made the 'plinking' sound and after a few seconds partially died, revs to almost zero, then picked up again and returned to normal (I throttled back a bit).
Could it be sticky valve? Is it interference valve/piston.. maybe noise is valve being struck by piston?
Andy