Pulled my pistons and found 2 things wrong.
1. All the pistons are tight on the wristpins, not super tight but tight none-the-less, much more so than when they were put in.

2. The rods, all 4, have signs of major heat by the wrist pins, see pics.



Before installation.

 

ouchie.... sure got hot in there.... I wonder why as well.....?!?!?!

 

Oil pump failed? - no oil circulation...overheating...engine go boom!

Maybe what you are seeing is from the oil squirters not working at all.

p.s. did you ever figure out what went wrong?

 

looks like the heat that was used when pushing the wrist pins in.

 

Are you sure that you weren't detonating at high rpm's or anything like that?

 

When you try to put 5 pistons in a 4 cylinder block, things get hot..........

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by gaskleppie &raquo;</TD></TR><TR><TD CLASS="quote">

When you try to put 5 pistons in a 4 cylinder block, things get hot..........

</TD></TR></TABLE>


LMFAO!!! not at your situation chad, but the stament above...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by gaskleppie &raquo;</TD></TR><TR><TD CLASS="quote">
When you try to put 5 pistons in a 4 cylinder block, things get hot..........

</TD></TR></TABLE>

LMAOOOOOOOOOOO

 

have you disassembled the oil pump yet? Oil P gauge? if so, what were you seeing before go boom?

 

Haven't figured it out yet. I did think the rod bolt let go, but now I'm thinking oil starvation as the bearing don't look good. I'll go snap a pic.

 

Cap bearings lined up 1-5








Forgot to take a pic of the last set...but it looks like the first set. Bearings are all bad in the middle, 2 outside bearings are fine, so the damage may have occured when the rod banged around the block.

Oil pump gear looks fine.

 

Ouch, how do the top of the pistons look? Lean? Any signs of detonation?

 

Wow, as i keep learning more about our cars i awlays see something that surprises me. This no doubt has me curious. i hope you find out what the problem was. Good luck with the new pistons.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by VTHokie &raquo;</TD></TR><TR><TD CLASS="quote">Ouch, how do the top of the pistons look? Lean? Any signs of detonation?</TD></TR></TABLE>

No, if anything car was running way too rich.

Another thing to think about, which I neglected to mention, my catch can, which was mounted two days before the lapping event was FULL.

Figure that one out.

 

Catchcan just collects vaporized oil from the crankcase. If it was full it means the engine was waaay too hot and/or crankcase pressure was really high...? Again me thinks there was a problem with oil circulation or just low oil level.

I'm surprised your bearings look that cooked.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Big Phat R &raquo;</TD></TR><TR><TD CLASS="quote">Catchcan just collects vaporized oil from the crankcase. If it was full it means the engine was waaay too hot and/or crankcase pressure was really high...? Again me thinks there was a problem with oil circulation or just low oil level.

I'm surprised your bearings look that cooked.</TD></TR></TABLE>

See, oil level was fine, measured before I went out (drove about 5 laps before it let go). Water temp was fine. Also, the outside bearings looked fine, the 3 inside (#2,3,and 4) were bad. Any idea why the rod tops got so hot?

 

Edit: just read your response to BPR, so my post is rather moot....

So chad, did you have an oil consumption problem at all? I know it was only your second session, and you were at the end of the front stretch (meaning you weren't in a hard turn where you would be more likely to have some oil issues with a stock oil pan).... but maybe it was an oil level problem.??

 

Hmmm, only tony knows that you heat the rods to put the pins in???

the rest of you all.... shut up.

 

did you have the wrist pins and pistons pin fitted by a reputable machine shop before they were installed in the block? just wondering since that's what we try to do whenever possible...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sgT &raquo;</TD></TR><TR><TD CLASS="quote">Hmmm, only tony knows that you heat the rods to put the pins in???

the rest of you all.... shut up.</TD></TR></TABLE>
I use a different method of installing OEM pistons. I put the wristpins in oil in the freezer. They slide in like butter.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b19coupe &raquo;</TD></TR><TR><TD CLASS="quote">
I use a different method of installing OEM pistons. I put the wristpins in oil in the freezer. They slide in like butter. </TD></TR></TABLE>

Much better method in my humble opinion. That way you avoid changing any heat treat proporties.


PS Not that I'm claiming know what the heat treat proporties of various rods, or how much you head them up to install the pins. But we (@ US Airways) usually dip interferance fit bushing, pins, etc. into liquid nitrogen for that exact reason.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PSU-TEG &raquo;</TD></TR><TR><TD CLASS="quote">

Much better method in my humble opinion. That way you avoid changing any heat treat proporties.


PS Not that I'm claiming know what the heat treat proporties of various rods, or how much you head them up to install the pins. But we (@ US Airways) usually dip interferance fit bushing, pins, etc. into liquid nitrogen for that exact reason.
</TD></TR></TABLE>

I agree that thats probably the better way, however given that it doesnt cause any
ill effects, and heat is more available than liquid nitrogen, i choose to useheat.
might try the freezer thing, but i need to find a freezer first.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sgT &raquo;</TD></TR><TR><TD CLASS="quote">

I agree that thats probably the better way, however given that it doesnt cause any
ill effects, and heat is more available than liquid nitrogen, i choose to useheat.
might try the freezer thing, but i need to find a freezer first.</TD></TR></TABLE>

Steve you don't have a freezer? j/k
Very interesting info. Thanks for sharing..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sgT &raquo;</TD></TR><TR><TD CLASS="quote">
heat is more available than liquid nitrogen, i choose to useheat.
</TD></TR></TABLE>

Agreed. I was just using it as an example to compare the idea. We only use liquid nitrogen be cause it is nice and quick. We also store certain rivets in a freezer (although not your ordinary home freezer) so that when installed they will expand to for a better hole fill.

And if there are not ill effects, I guess cooling the pin instead of heating the rod would not be much better. Just different.

I guess I've just gotten to use to dealing with applications where heat treat proporties can be very critical under the watchful eyes of the FAA.

Modified by PSU-TEG at 1:25 PM 7/16/2003


Modified by PSU-TEG at 9:53 PM 7/16/2003

 

My machinest heated my rods to put the wrist pins in. It's a common practice, but he did tell me that he has seen some rods that were heated too much and majorly discolored, kinda like the rods above.

So what he does is use a welders crayon to mark the small end of the rod. It goes in the fire, and when the rod is at a specific temp the crayon mark will melt, and then the pin gets pushed through.