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VaccaRabite
Okay, a while back I had the #2 exhaust rocker back off while breaking in the engine.

I fixed that, and rebuilt the carbs.

Tonight I reset the valve gap and, ran it for the first time. It runs, but I heard a noise I did not like. There is a leak somewhere on the 1/2 head bank. Watch this video I made. it is me cranking the engine on my test stand. No fuel or spark, only cranking. The spark plugs are in to force compression.

You can hear a "fffffffft, fffffffft, ffffffffft" sound, that I don't think is supposed to be there.
Link to the video on Flickr


Zach
VaccaRabite
Also, and I am frusterated by this, but I am going to have to pull off the oil pump plate and replace that gasket. It is not sealing, and leaks whenever the engine runs.

Better to find out now then when I get the motor in the car, I guess.

Zach
VaccaRabite
Bump to the top.

Zach
TheCabinetmaker
Zach, its hard to tell in the vid as sound quality is never real great, but it almost sounds retarded to me. exhaust header nuts have a tendecy to loosen slightly after the first run. Maybe retorque them?
toon1
I can sorta hear what you are talking about, hard to tell with through the vid.

Have you tried to fire it?
VaccaRabite
Yeah. I fired it. It runs on all 4. Each carb is drawing the same amount of air. I have the idle set at 2K in order to seat the rings, but it was idling fine at about 650 rpm before I opened up the idle adjustment screws.

There could be an exhaust gasket leak between the stub pipe and the header pipe. I have had to take the 1/2 head pipes off a few times, and the gaskets have seen better days. But I did not see fit to source new gaskets until I was done taking the pipes off. I have to remove those pipes in order to use the Tangerine lifting plate.

I'll take a vid of the engine running this afternoon after I am done baby duty, and have the corn and beans planted.

Zach
toon1
An EX leak would have to be pretty large to be able to hear while craning. Did a ex gasket fall out by chance.

Can you hear the leak with the engine running?
rhodyguy
use a section of garden hose to pin point the noise. bummer over the leak sooner. now than later. 650 is a pretty low idle.
LowGT
Maybe a silly question, but are the spark plugs torqued? I got a noise like that once when I just hand screwed the spark plugs in but didn't torque them.

Sounds like air is being forced past, so I would check anything holding compression. Valves, head gaskets, spark pugs, etc...
VaccaRabite
Vid of the first few moments of break in...

There. The smoke when away somewhere around 10 minutes in. How does it sound?

Other vid or on my build thread What the World needs now....

Let me know how it sounds.

Zach
bottomend
QUOTE(Vacca Rabite @ May 25 2008, 04:25 PM) *

Vid of the first few moments of break in...

There. The smoke when away somewhere around 10 minutes in. How does it sound?

Other vid or on my build thread What the World needs now....

Let me know how it sounds.

Zach


Unrelated but... running your engine for the first time at 2000-2500 does not break the rings in. Thats the cam break in time only. Rings are broken in after the engine is installed and load is applied during acceleration/deceleration.

The engine sounds pretty good as is. Are you trying to pinpoint the higher pitched you're hearing? Anything super out of the ordinary should be pretty evident, otherwise just go through everything again and make sure stuff is tightened down to spec. At this point, if nothing is clanking and trying to destroy itself, then theres not a whole lot it could be. Just check all the normal stuff i.e. valve adjstment, intakes, exhaust, spinning things rubbing against stuff ect.
purple
why are you doing this with the tranny in gear? I remember it was a bitch to do anything on my engine one day. it didnt want to play nice, and the whole car shook (it was half on jackstands) and couldnt figure out why it wasnt starting. turns out i had it in gear. also, i dont hear a leak in your video, just an engine cranking...SLOW mayhaps take it out of gear for that too?
VaccaRabite
QUOTE(purple @ May 28 2008, 06:08 PM) *

why are you doing this with the tranny in gear? I remember it was a bitch to do anything on my engine one day. it didnt want to play nice, and the whole car shook (it was half on jackstands) and couldnt figure out why it wasnt starting. turns out i had it in gear. also, i dont hear a leak in your video, just an engine cranking...SLOW mayhaps take it out of gear for that too?

It did not seem to make a difference, and I could not figure out which way to actuate the shifter thingy to take it out of gear.

By the way, I am happy to see another Order Of The Stick fan!

Zach
r_towle
grab the ball and go forward and back with it...you will feel it go into gear at each end..forward and backward...

then you can push it up into the tranny, or pull it done...only when you are in the middle.
You have three levels, up tight, down a 1/4 inch, and down 1/2 inch..
Those are the gates you feel on the shifter.
Forward is a gear, back is a gear...middle is always neutral
Does not matter what level the shifter is at, middle is neutral.

I cant hear the sound, sorry.
If I was closer I would come over...

Rich
Gint
BTW - With the engine running the trans will turn an unloaded output shaft even when it's in neutral.
VaccaRabite
QUOTE(Gint @ May 29 2008, 12:42 AM) *

BTW - With the engine running the trans will turn an unloaded output shaft even when it's in neutral.


THANK YOU!

My trans was in neutral (I checked). I was starting to worry that something was wrong.

Zach
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