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> Ugh -Looks Like I have a Burned Exhaust valve, Just in time for Okteenerfest
Mblizzard
post Aug 1 2016, 09:59 AM
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Well this will be fun!

I noted an odd exhaust note from my glorious CFR exhaust. Thought something had come loose inside the exhaust. Removed, checked, and all good.

Checked valve adjustment. All good.

Checked compression. 150 PSI plus except for #3 at 100. (IMG:style_emoticons/default/headbang.gif) Did the add some oil to cylinder with no change in compression.

Going to remove the exhaust tonight again and take off the valve train on that side and pressurize the cylinder to see if I can verify the which valve is leaking.

A couple of questions. Fist I bet no one has a known good 73 2.0 L head laying around that they would be willing to sell or loan? Just looking to minimize down time.

Next any suggestions on a place to turn the head around quickly? Not sure if it is just the exhaust valve but considering it has less than 5K on the new top end and it is holding 100 psi I am betting it is not seriously damaged.

While I am there, might as well replace the rings. so I will be needing a set of 96 mm rings.
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Eric_Shea
post Aug 1 2016, 10:21 AM
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Replace both heads with big valve heads... best investment in fun for that motor. I might have a pair. (IMG:style_emoticons/default/wink.gif)
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Mblizzard
post Aug 1 2016, 10:24 AM
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QUOTE(Eric_Shea @ Aug 1 2016, 08:21 AM) *

Replace both heads with big valve heads... best investment in fun for that motor. I might have a pair. (IMG:style_emoticons/default/wink.gif)


True but not sure I can handle the "investment" in what the heads cost but what you got?
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r_towle
post Aug 1 2016, 03:55 PM
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I suggest you pull the motor out of the car...it will be faster.
Also, you need to do more diagnosis before you go buying parts.

How old is the motor?
Do you think there may be alot of carbon build up in the motor, enough to possibly make one of the rings get stuck, or a valve not close right?
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Bartlett 914
post Aug 1 2016, 04:08 PM
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QUOTE(r_towle @ Aug 1 2016, 04:55 PM) *

I suggest you pull the motor out of the car...it will be faster.


(IMG:style_emoticons/default/idea.gif)
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Mblizzard
post Aug 1 2016, 04:26 PM
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QUOTE(r_towle @ Aug 1 2016, 01:55 PM) *

I suggest you pull the motor out of the car...it will be faster.
Also, you need to do more diagnosis before you go buying parts.

How old is the motor?
Do you think there may be alot of carbon build up in the motor, enough to possibly make one of the rings get stuck, or a valve not close right?


Less than 5k since McMark did the top end. Will do a pressurized blow through to see.
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JOEPROPER
post Aug 1 2016, 04:41 PM
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I'd do a leak down test and maybe pop that valve cover off to get a look at valve springs, rockers etc... How did it run before? I don't think I'd be too eager to pull the engine before doing a little more investigating. (IMG:style_emoticons/default/popcorn[1].gif)
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DaveO90s4
post Aug 1 2016, 04:55 PM
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Worth checking valve clearances before removing rocker gear? Excessive clearance might indicate that valve not fully closed?

Dave
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porschetub
post Aug 1 2016, 05:53 PM
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QUOTE(DaveO90s4 @ Aug 2 2016, 10:55 AM) *

Worth checking valve clearances before removing rocker gear? Excessive clearance might indicate that valve not fully closed?

Dave


(IMG:style_emoticons/default/idea.gif) ,I think you mean lack of clearance and the valve may still be open.
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Mblizzard
post Aug 1 2016, 05:54 PM
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QUOTE(DaveO90s4 @ Aug 1 2016, 02:55 PM) *

Worth checking valve clearances before removing rocker gear? Excessive clearance might indicate that valve not fully closed?

Dave


Believe me I am doing all of the easy things first. But the sudden change and fact that I have checked all of the valves especially #3 it is hard to see that it could be anything else.
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r_towle
post Aug 1 2016, 05:58 PM
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That sucks.
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Mblizzard
post Aug 2 2016, 10:13 AM
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Thanks to Eric at PMB looks like I have a couple of new big valve heads headed my way!

Of course when I tell my wife how much this will costs I might be sleeping in my 914!
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Mblizzard
post Aug 2 2016, 05:18 PM
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Can't wait on this package to show up!

Attached Image

Just wish the engine fairies would stop by and install them this weekend!
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Mblizzard
post Aug 6 2016, 02:03 PM
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Well engine out and torn down to the heads. Will start diggin in tomorrow.

Of course found more things to fix. CV joint fell apart on the passenger side. WTF? It is always something.
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stugray
post Aug 6 2016, 02:14 PM
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QUOTE(Mblizzard @ Aug 6 2016, 02:03 PM) *

Well engine out and torn down to the heads. Will start diggin in tomorrow.

Of course found more things to fix. CV joint fell apart on the passenger side. WTF? It is always something.

The CVs often 'fall apart' when removing the drivetrain, but was the cage broken?
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lonewolfe
post Aug 6 2016, 03:47 PM
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QUOTE(Mblizzard @ Aug 2 2016, 09:13 AM) *

Thanks to Eric at PMB looks like I have a couple of new big valve heads headed my way!

Of course when I tell my wife how much this will costs I might be sleeping in my 914!


What size valves are in the replacement heads? Are they 2.0L heads?
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Mblizzard
post Aug 6 2016, 06:01 PM
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QUOTE(lonewolfe @ Aug 6 2016, 01:47 PM) *

QUOTE(Mblizzard @ Aug 2 2016, 09:13 AM) *

Thanks to Eric at PMB looks like I have a couple of new big valve heads headed my way!

Of course when I tell my wife how much this will costs I might be sleeping in my 914!


What size valves are in the replacement heads? Are they 2.0L heads?


44 intake 38 exhaust. Original 2.0 heads.
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Mblizzard
post Aug 6 2016, 06:02 PM
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QUOTE(stugray @ Aug 6 2016, 12:14 PM) *

QUOTE(Mblizzard @ Aug 6 2016, 02:03 PM) *

Well engine out and torn down to the heads. Will start diggin in tomorrow.

Of course found more things to fix. CV joint fell apart on the passenger side. WTF? It is always something.

The CVs often 'fall apart' when removing the drivetrain, but was the cage broken?


Cage looked good but the clip on end was gone!
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Bartlett 914
post Aug 6 2016, 06:07 PM
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QUOTE(Mblizzard @ Aug 6 2016, 07:02 PM) *

QUOTE(stugray @ Aug 6 2016, 12:14 PM) *

QUOTE(Mblizzard @ Aug 6 2016, 02:03 PM) *

Well engine out and torn down to the heads. Will start diggin in tomorrow.

Of course found more things to fix. CV joint fell apart on the passenger side. WTF? It is always something.

The CVs often 'fall apart' when removing the drivetrain, but was the cage broken?


Cage looked good but the clip on end was gone!

Is the clip really necessary? I would want one installed but I believe the shaft floats laterally in the bearing once installed.
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Mblizzard
post Aug 6 2016, 07:08 PM
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QUOTE(Bartlett 914 @ Aug 6 2016, 04:07 PM) *

QUOTE(Mblizzard @ Aug 6 2016, 07:02 PM) *

QUOTE(stugray @ Aug 6 2016, 12:14 PM) *

QUOTE(Mblizzard @ Aug 6 2016, 02:03 PM) *

Well engine out and torn down to the heads. Will start diggin in tomorrow.

Of course found more things to fix. CV joint fell apart on the passenger side. WTF? It is always something.

The CVs often 'fall apart' when removing the drivetrain, but was the cage broken?


Cage looked good but the clip on end was gone!

Is the clip really necessary? I would want one installed but I believe the shaft floats laterally in the bearing once installed.


I am pretty sure the clip is necessary. It is rare that parts are added that are not needed and the clip is present on most CV joints I have ever seen.
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