Author Topic: Piston damage diagnosis - pictures  (Read 4114 times)

June 12, 2008, 07:29:10 pm

captainpartytime

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Piston damage diagnosis - pictures
« on: June 12, 2008, 07:29:10 pm »
I just purchased a used 1.6 ECOdiesel. I am attempting to rebuild the motor (for my first time) and drop it into my westfalia vanagon. I need help diagnosing this piston damage. I'm assuming one of the valves hit the top of the piston and made the impression. The pictured piston is the worst of the two with the other having a faint imprint of the valve with no real difference in surface height. The piston pictured has a very slight indentation that can be felt when running my finger of the piston. My question is...do I have to replace the pistons or are these pistons salvageable? Is this normal for a "low mileage" used motor or should I take this up with the seller? I plan on honing and re-ringing the pistons as well as changing all the seals and bearings. Any suggestions would be very much appreciated.
 

-Kerry

1982 Diesel Westfalia Vanagon
1989 Wolfsburg 7-Passenger Vanagon

Reply #1June 12, 2008, 08:08:05 pm

rabbitman

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Piston damage diagnosis - pictures
« Reply #1 on: June 12, 2008, 08:08:05 pm »
Yer pistons are fine......maybe smoothen the ridge just a bit. There's no good excuse for a low mileage engine to do that, I doubt the belt broke or all your pistons would look like that. Check the valves real close and see if there bent, it could've been out of time just a bit and/or got revved too high and floated the valve. Good luck

PS. Welcome to the forum :D Read lots and you'll learn tons.
'82 Rabbit, I put on a euro vnt-15, 2.25" DP, 2.5" exhaust, the result.....it whistled.

I removed the turbo, made a toilet bowl 2.5" DP, the result....it was deafening. Now it has a homemade muffler up front and a thrush in the rear, the result.....less loud.
Watch: AGENDA, GRINDING AMERICA DOWN

Reply #2June 12, 2008, 08:25:42 pm

Vincent Waldon

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Piston damage diagnosis - pictures
« Reply #2 on: June 12, 2008, 08:25:42 pm »
Since misery loves company, here's mine:




As per Rabbitman... smooth out the ridge and away you go.  Engine's been running fine for months now.
Vince

Edmonton, Alberta, Canada
2001 silver TDI Jetta Malone Stage 1.5 , 2001 blue TDI Jetta SBIII 216s Malone Stage 3, 1970 Bay Window bus

Gone but not forgotten: 1969/1971 Beetles, 1969/1974 Westies, 1979 Rabbit, 1986 TD Jetta, 1992 gas Jetta, 1994 TD Jetta

Reply #3June 12, 2008, 08:40:36 pm

captainpartytime

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Piston damage diagnosis - pictures
« Reply #3 on: June 12, 2008, 08:40:36 pm »
Any recommendations on smoothing out the ridge? BTW Thanks for the welcome! :D
-Kerry

1982 Diesel Westfalia Vanagon
1989 Wolfsburg 7-Passenger Vanagon

Reply #4June 12, 2008, 09:20:45 pm

myke_w

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Piston damage diagnosis - pictures
« Reply #4 on: June 12, 2008, 09:20:45 pm »
yours isnt bad at all..  I'd just wire wheel it smooth and get on with it. I've seen far larger impressions in pistons on motors that ran great.
Contact me for hard to find for idi and tdi parts


Reply #5June 12, 2008, 09:33:52 pm

jackbombay

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Piston damage diagnosis - pictures
« Reply #5 on: June 12, 2008, 09:33:52 pm »
PARTY TIME!!!!!! ;-)

  Welcome!

  As most have said, it should be fine, but if you're worried you can check the protrusion above the deck with a straight edge and some feeler gauges so you know the rod isn't bent.

Reply #6June 12, 2008, 10:29:16 pm

Vincent Waldon

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Piston damage diagnosis - pictures
« Reply #6 on: June 12, 2008, 10:29:16 pm »
Yeah, the mushrooming is pretty impressive don't cha think ??

The PO replaced the head but left the pistons as pictured so I never got to see what the valves and head looked like...  :cry:
Vince

Edmonton, Alberta, Canada
2001 silver TDI Jetta Malone Stage 1.5 , 2001 blue TDI Jetta SBIII 216s Malone Stage 3, 1970 Bay Window bus

Gone but not forgotten: 1969/1971 Beetles, 1969/1974 Westies, 1979 Rabbit, 1986 TD Jetta, 1992 gas Jetta, 1994 TD Jetta