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nebreitling
SO, engine was still running well, but my #3 intake kept tightening up on me. smog ports in the heads were stripped. figured i'd pull the engine and see what's up. first time opening up a Type IV. hoping that i'd just need a valve job...

okay, first surprise: the jugs measure 96mm across.

guess i wasn't in Bp afterall.


second surprise: there's a bunch of melted shit all over #3 piston (and a little over the rest of them). What the hell is this?

pin holes in the middle of 3 out of 4 pistons. cylinders look okay. #3 intake push rod has a weird gash in it.

ANY comments welcome. specifically, what is that junk in #3?



#3 and #4 heads

IPB Image


#3 piston

IPB Image

#4 piston (sorry, andy-esque)

IPB Image

# 2 and #1 heads

IPB Image

#2 and #1 cylinders

IPB Image
Aaron Cox
that cant be good for compression (pin holes)

yummy carbon!

is that a head leakage stain on the #3 head?
nebreitling
yeah, minor leakage there and a couple other places. looks worse than it is because of some PB Blaster running down it... actually, in terms of head leakage, i was expecting worse.



yeah, i'm thinking those holes probably kept the power down ohmy.gif



so that buildup is just carbon?

i thought i'd chewed up a piece of aluminum foil or something...
SirAndy
QUOTE(nebreitling @ Nov 12 2004, 06:55 PM)
pin holes

pin holes? wtf?

confused24.gif Andy
SirAndy
QUOTE(nebreitling @ Nov 12 2004, 07:07 PM)
so that buildup is just carbon?

yupp ...

looks like one cylinder (#4 i think) was running waaaaaay lean!
not gud, you need to find out why and fix it ...
smash.gif Andy
newdeal2
Do ya think you can make the pictures any bigger??!!

I have a cable modem and 5 min's later still trying!
nebreitling
sorry... britain's putting them on his site...

will get quicker...
Aaron Cox
QUOTE(SirAndy @ Nov 12 2004, 07:10 PM)
QUOTE(nebreitling @ Nov 12 2004, 07:07 PM)
so that buildup is just carbon?

yupp ...

looks like one cylinder (#4 i think) was running waaaaaay lean!
not gud, you need to find out why and fix it ...
smash.gif Andy

how was yopur timing? ask zeke what happens when you timing is too advanced (piston holes)
Trekkor
Nathan, you're not going to like this one bit.

The engine problems are a direct result of your *secret* console toggle switch. ohmy.gif

Also, this turn of events regarding the newly discovered motor size means: when I beat you, I really beat you! And... when you beat me it didn't count! lol2.gif

w00t.gif Woooooww whheeeeee!

KT

( messed up , I know ) cool_shades.gif
nebreitling
i kept it timed to spec. fuel pressure at 30. mps calibrated.

i'm guessing that #4 is a fuel injector problem.

honestly, i think it was like this when i got the car a year and a half ago. it ran hot when i first got it. once i tuned it a refurbished some of the FI, it cooled down.

damn thing was still running hard when i pulled the engine last week.
nebreitling
keep telling yourself that, trekkor. it will then be all the more sweet when i beat you in your /6!


biggrin.gif
Aaron Cox
QUOTE(nebreitling @ Nov 12 2004, 07:33 PM)
damn thing was still running hard when i pulled the engine last week.

imagine what it wil do witout holes in the pistons wink.gif

WARNING - Lame attempt at a joke ahead

are those church pistons? theyre Holy rolleyes.gif
nebreitling
pics have been resized. thanks anyway britain.



aaron, that's exactly why i don't feel guilty having run in Bp! there's no way that was putting out more power than a fresh 2liter
Trekkor
uh-huh...uh-huh. lol2.gif

KT
mightyohm
what fi were you running nathan? if it was stock d-jet i am not that surprised it was running lean unless the MPS had been recalibrated for the displacement increase.

that intake valve on the cyl on the left looks pretty far receeded into the head. maybe someone who knows what they are talking about can comment?
muddboy
Ok.... the "holes" in the pistons, as far as the ones in the centers, are not holes. I can't say without really looking at them (holding them in hand) but they should be just a locating hole for the tooling when they pistons are made. You dont see them in the one piston because their is junk deposted in it.

Yeah the valve it receding.

And the wierd gash in the pushrod, does it go all the way around the pushrod? like a ring inch or so down from the end? or about 3 inch long "rub" right in the middle?
Demick
Jesus - is everyone running cheater 2056 motors in the GGR series?????

Demick
Demick
Next Britain will tear down his 1.7 and find out that it's really a big bore 1911.

Then Trekkor will tear down his motor just for fun after putting in his six and find another set of 96mm pistons!

Ha Ha.

Demick
Trekkor
w00t.gif
Jake Raby
Its just got alot of long hard miles on it.. Looks pretty damn good actually!


Its a good thing you caught it now because a tightening valve is a stretching valve that can and WILL take the entire engine out if not caught when the head snaps off suddenly.
Britain Smith
QUOTE(Demick @ Nov 13 2004, 08:56 AM)
Next Britain will tear down his 1.7 and find out that it's really a big bore 1911.

Then Trekkor will tear down his motor just for fun after putting in his six and find another set of 96mm pistons!

Ha Ha.

Demick

I wouldn't bet on that...it would be nice though.

-Britain
SLITS
Or the seat is pulling into the head!

Under lean conditions, the aluminum of the piston will vaporize.

The "magic switch" - I assume your advancing the timing to never-never land in hopes of more power out of the turns at low rpm. It may have worked for the drag racers, but sure as hell didn't work for us in road-racing - just made the engine heat up faster.
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