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914World.com _ 914World Garage _ Off with their heads!
Posted by: nebreitling Nov 12 2004, 07:55 PM
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
#3 piston
#4 piston (sorry, andy-esque)
# 2 and #1 heads
#2 and #1 cylinders
Posted by: Aaron Cox Nov 12 2004, 08:00 PM
that cant be good for compression (pin holes)
yummy carbon!
is that a head leakage stain on the #3 head?
Posted by: nebreitling Nov 12 2004, 08:07 PM
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 
so that buildup is just carbon?
i thought i'd chewed up a piece of aluminum foil or something...
Posted by: SirAndy Nov 12 2004, 08:09 PM
pin holes? wtf?
Andy
Posted by: SirAndy Nov 12 2004, 08:10 PM
yupp ...
looks like one cylinder (#4 i think) was running waaaaaay lean!
not gud, you need to find out why and fix it ...
Andy
Posted by: newdeal2 Nov 12 2004, 08:17 PM
Do ya think you can make the pictures any bigger??!!
I have a cable modem and 5 min's later still trying!
Posted by: nebreitling Nov 12 2004, 08:26 PM
sorry... britain's putting them on his site...
will get quicker...
Posted by: Aaron Cox Nov 12 2004, 08:28 PM
yupp ...
looks like one cylinder (#4 i think) was running waaaaaay lean!
not gud, you need to find out why and fix it ...
Andy how was yopur timing? ask zeke what happens when you timing is too advanced (piston holes)
Posted by: trekkor Nov 12 2004, 08:29 PM
Nathan, you're not going to like this one bit.
The engine problems are a direct result of your *secret* console toggle switch.
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! 
Woooooww whheeeeee!
KT
( messed up , I know ) 
Posted by: nebreitling Nov 12 2004, 08:33 PM
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.
Posted by: nebreitling Nov 12 2004, 08:35 PM
keep telling yourself that, trekkor. it will then be all the more sweet when i beat you in your /6!
Posted by: Aaron Cox Nov 12 2004, 08:35 PM
imagine what it wil do witout holes in the pistons
WARNING - Lame attempt at a joke ahead
are those church pistons? theyre Holy
Posted by: nebreitling Nov 12 2004, 08:50 PM
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
Posted by: trekkor Nov 12 2004, 09:30 PM
uh-huh...uh-huh.
KT
Posted by: jkeyzer Nov 12 2004, 10:53 PM
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?
Posted by: muddboy Nov 13 2004, 12:12 AM
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?
Posted by: Demick Nov 13 2004, 09:51 AM
Jesus - is everyone running cheater 2056 motors in the GGR series?????
Demick
Posted by: Demick Nov 13 2004, 09:56 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
Posted by: trekkor Nov 13 2004, 10:11 AM
Posted by: Jake Raby Nov 13 2004, 11:11 AM
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.
Posted by: Britain Smith Nov 13 2004, 11:23 AM
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
Posted by: SLITS Nov 13 2004, 11:33 AM
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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