SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: Wayne Zighter on October 23, 2011, 01:02:24 PM

Title: detonation damage
Post by: Wayne Zighter on October 23, 2011, 01:02:24 PM

went to el cap a couple of weeks ago, started having major loss of power and what I thought was an exhaust leak. my own damn fault though I know better (done it before) to much timing, to high water temp 200*/205*

Title: Re: detonation damage
Post by: IRRebel on October 23, 2011, 03:39:12 PM

Detonation damage, yeah I see a little of that, but I also see a LOT of valve damage on the one piston, and some nice smiley's from the intakeand exhaust valves on the other two. I think the two MIGHT be related........just me......

Ray

In other words, detonation didn't cause this. Looks to me Cam timing did. JMHO.

Title: Re: detonation damage
Post by: Second Chance on October 23, 2011, 04:06:16 PM

Ray, do you think detonation caused the crown to blow off to the ring lands ?
I suppose it would have to be detonating pretty bad for that to happen.
Would'nt you see signs on the plugs before it got that bad ?
Think I'm gonna pull the heads off ours and take a peek this off season.

Danny

Title: Re: detonation damage
Post by: IRRebel on October 23, 2011, 04:40:01 PM

Quote from: wetnreckless on October 23, 2011, 04:06:16 PM

Ray, do you think detonation caused the crown to blow off to the ring lands ?
I suppose it would have to be detonating pretty bad for that to happen.
Would'nt you see signs on the plugs before it got that bad ?
Think I'm gonna pull the heads off ours and take a peek this off season.

Danny

LOL! Yes, I would but that, and why I said i saw detonation damage. But I doubt very seriously that was the ultimate cause here Dan. As stated, I think the ultimate cause is obvious. Detonation was the result.......not the cause...........

Ray

Title: Re: detonation damage
Post by: enginedoctor on October 23, 2011, 06:53:40 PM

V/P Clearances/ Detonation....... jus mho

Title: Re: detonation damage
Post by: Wayne Zighter on October 23, 2011, 08:08:52 PM

Quote from: IRRebel on October 23, 2011, 03:39:12 PM

Detonation damage, yeah I see a little of that, but I also see a LOT of valve damage on the one piston, and some nice smiley's from the intakeand exhaust valves on the other two. I think the two MIGHT be related........just me......

Ray

In other words, detonation didn't cause this. Looks to me Cam timing did. JMHO.

I thought it was valve clearence problems at first when I lifted the head, untill I turned it over and saw the head and valves were basicly untouched. the stamping you see on the piston is from the ring land. if you take another look you'll see it was hitting below the valves

Title: Re: detonation damage
Post by: lupo1904 on October 23, 2011, 08:34:30 PM

ooouch bud that sucks let me know if you need any help