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914World.com _ 914World Garage _ Ugh -Looks Like I have a Burned Exhaust valve
Posted by: Mblizzard Aug 1 2016, 09:59 AM
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. 
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.
Posted by: Eric_Shea Aug 1 2016, 10:21 AM
Replace both heads with big valve heads... best investment in fun for that motor. I might have a pair. 
Posted by: Mblizzard Aug 1 2016, 10:24 AM
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.
True but not sure I can handle the "investment" in what the heads cost but what you got?
Posted by: r_towle Aug 1 2016, 03:55 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?
Posted by: Bartlett 914 Aug 1 2016, 04:08 PM
QUOTE(r_towle @ Aug 1 2016, 04:55 PM)
I suggest you pull the motor out of the car...it will be faster.
Posted by: Mblizzard Aug 1 2016, 04:26 PM
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.
Posted by: JOEPROPER Aug 1 2016, 04:41 PM
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. ![popcorn[1].gif](style_emoticons/default/popcorn[1].gif)
Posted by: DaveO90s4 Aug 1 2016, 04:55 PM
Worth checking valve clearances before removing rocker gear? Excessive clearance might indicate that valve not fully closed?
Dave
Posted by: porschetub Aug 1 2016, 05:53 PM
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
,I think you mean lack of clearance and the valve may still be open.Posted by: Mblizzard Aug 1 2016, 05:54 PM
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.
Posted by: r_towle Aug 1 2016, 05:58 PM
That sucks.
Posted by: Mblizzard Aug 2 2016, 10:13 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!
Posted by: Mblizzard Aug 2 2016, 05:18 PM
Can't wait on this package to show up!
Just wish the engine fairies would stop by and install them this weekend!
Posted by: 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.
Posted by: stugray Aug 6 2016, 02:14 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?
Posted by: lonewolfe Aug 6 2016, 03:47 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?
Posted by: Mblizzard Aug 6 2016, 06:01 PM
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.
Posted by: Mblizzard Aug 6 2016, 06:02 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!
Posted by: Bartlett 914 Aug 6 2016, 06:07 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.
Posted by: Mblizzard Aug 6 2016, 07:08 PM
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.
Posted by: Mblizzard Aug 7 2016, 06:29 PM
Long day but found a few interesting things. Which one of these was not firing?
Well new heads going on within only minor issues. 
One more,long day then back on road.
Posted by: lonewolfe Aug 7 2016, 06:47 PM
Hey Mike! is this a stock size 2.0L motor? It seems to me that 44x38 valves would be too large for a 2.0L. How does the motor run differently with those large valves? What compression are you running and which cam? Are you still running the SSI's with the Tangerine Evo 4 muffler? I bought the same mufflwe from Tangerine after I heard the sound clips from your car!
Posted by: Mblizzard Aug 7 2016, 07:11 PM
QUOTE(lonewolfe @ Aug 7 2016, 04:47 PM)
Hey Mike! is this a stock size 2.0L motor? It seems to me that 44x38 valves would be too large for a 2.0L. How does the motor run differently with those large valves? What compression are you running and which cam? Are you still running the SSI's with the Tangerine Evo 4 muffler? I bought the same mufflwe from Tangerine after I heard the sound clips from your car!
It is a 2056 so the valves are not too big.
Leaving a bit on the table as I am still running stock cam. Will swap cam at some point to get into that 120 hp range.
Running SS heat exchangers. But planning to get the CFR headers at some point.
I had hoped to do cam and heads at the same time but the budget would not allow.
Posted by: lonewolfe Aug 7 2016, 07:36 PM
QUOTE(Mblizzard @ Aug 7 2016, 06:11 PM)
QUOTE(lonewolfe @ Aug 7 2016, 04:47 PM)
Hey Mike! is this a stock size 2.0L motor? It seems to me that 44x38 valves would be too large for a 2.0L. How does the motor run differently with those large valves? What compression are you running and which cam? Are you still running the SSI's with the Tangerine Evo 4 muffler? I bought the same mufflwe from Tangerine after I heard the sound clips from your car!
It is a 2056 so the valves are not too big.
Leaving a bit on the table as I am still running stock cam. Will swap cam at some point to get into that 120 hp range.
Running SS heat exchangers. But planning to get the CFR headers at some point.
I had hoped to do cam and heads at the same time but the budget would not allow.
I know all about that budget factor. Fortunately, I'm a pretty patient guy. Have you been happy with the Evo 4 muffler?
Posted by: cwpeden Aug 7 2016, 07:50 PM
QUOTE(Mblizzard @ Aug 6 2016, 06:08 PM)
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.
Pretty sure they serve a purpose...The CV was toast, both inner race and outer.
Posted by: r_towle Aug 7 2016, 07:56 PM
QUOTE(Mblizzard @ Aug 7 2016, 08:29 PM)
Long day but found a few interesting things. Which one of these was not firing?
Well new heads going on within only minor issues.
One more,long day then back on road.
Ignition related?
Posted by: Mblizzard Aug 8 2016, 04:15 AM
QUOTE(r_towle @ Aug 7 2016, 05:56 PM)
QUOTE(Mblizzard @ Aug 7 2016, 08:29 PM)
Long day but found a few interesting things. Which one of these was not firing?
Well new heads going on within only minor issues.
One more,long day then back on road.
Ignition related?
Pretty sure compression related. Less than 100 psi on the black cylinder.
Posted by: Mblizzard Aug 8 2016, 04:17 AM
QUOTE(lonewolfe @ Aug 7 2016, 05:36 PM)
QUOTE(Mblizzard @ Aug 7 2016, 06:11 PM)
QUOTE(lonewolfe @ Aug 7 2016, 04:47 PM)
Hey Mike! is this a stock size 2.0L motor? It seems to me that 44x38 valves would be too large for a 2.0L. How does the motor run differently with those large valves? What compression are you running and which cam? Are you still running the SSI's with the Tangerine Evo 4 muffler? I bought the same mufflwe from Tangerine after I heard the sound clips from your car!
It is a 2056 so the valves are not too big.
Leaving a bit on the table as I am still running stock cam. Will swap cam at some point to get into that 120 hp range.
Running SS heat exchangers. But planning to get the CFR headers at some point.
I had hoped to do cam and heads at the same time but the budget would not allow.
I know all about that budget factor. Fortunately, I'm a pretty patient guy. Have you been happy with the Evo 4 muffler?
Extremely happy with Evo. Great sound, well made, seems to add a bit of power right in the mid range, and looked really good!
Posted by: 76-914 Aug 8 2016, 01:23 PM
QUOTE(Mblizzard @ Aug 8 2016, 03:15 AM)
QUOTE(r_towle @ Aug 7 2016, 05:56 PM)
QUOTE(Mblizzard @ Aug 7 2016, 08:29 PM)
Long day but found a few interesting things. Which one of these was not firing?
Well new heads going on within only minor issues.
One more,long day then back on road.
Ignition related?
Pretty sure compression related. Less than 100 psi on the black cylinder.
Did the leak down point at the exhaust or intake?
Posted by: Mblizzard Aug 8 2016, 01:40 PM
QUOTE(76-914 @ Aug 8 2016, 11:23 AM)
QUOTE(Mblizzard @ Aug 8 2016, 03:15 AM)
QUOTE(r_towle @ Aug 7 2016, 05:56 PM)
QUOTE(Mblizzard @ Aug 7 2016, 08:29 PM)
Long day but found a few interesting things. Which one of these was not firing?
Well new heads going on within only minor issues.
One more,long day then back on road.
Ignition related?
Pretty sure compression related. Less than 100 psi on the black cylinder.
Did the leak down point at the exhaust or intake?
Exhaust.
Posted by: Mblizzard Aug 11 2016, 07:05 PM
Well hopefully this weekend will see me driving again. It is funny haw many little pats it takes to get this done and how lucky we are to have some really good vendors.
PMB, Aasse, Ecklers, Bruce Stone, CFR, 914 Rubber, and others all supplied parts.
Posted by: Mblizzard Aug 16 2016, 02:23 PM
Well looks like it may have been a bit more serious than a valve.
That looks like a scratch that will buff out. Right? 
Posted by: 76-914 Aug 16 2016, 02:31 PM
Uhhh, no!
Posted by: lonewolfe Aug 16 2016, 03:27 PM
I think the original 2.0 heads are no longer worth the money to repair. They always seem to crack. I have three sets of 2.0 heads and the all have cracks. Once you get them welded up a complete valve job with new seats and you're in the $1000 range and they're just going to crack again. It's a shame that nobody is making new 2.0 heads with modern alloys that are more durable. Thank goodness we at least have AMC heads to build up as replacements. Anyone have any cracking issues with AMC heads?
Posted by: HAM Inc Aug 16 2016, 06:12 PM
QUOTE(lonewolfe @ Aug 16 2016, 02:27 PM)
I think the original 2.0 heads are no longer worth the money to repair. They always seem to crack. I have three sets of 2.0 heads and the all have cracks. Once you get them welded up a complete valve job with new seats and you're in the $1000 range and they're just going to crack again. It's a shame that nobody is making new 2.0 heads with modern alloys that are more durable. Thank goodness we at least have AMC heads to build up as replacements. Anyone have any cracking issues with AMC heads?
So far I have yet to see an AMC head crack.
Seen them come back for service from track cars that ran over 1400* EGT's. Warped them and killed the valve job, but they didn't crack.
Seen them abused on CA busses with clogged catalytic converters that heated the heads so high it degraded the 1800* rated exhaust seats we install. Again, warped but not cracked.
They are very good castings, but the parts are garbage.
Posted by: craig downs Aug 16 2016, 07:21 PM
That's good to know. 
Posted by: Mblizzard Aug 16 2016, 07:28 PM
QUOTE(HAM Inc @ Aug 16 2016, 04:12 PM)
QUOTE(lonewolfe @ Aug 16 2016, 02:27 PM)
I think the original 2.0 heads are no longer worth the money to repair. They always seem to crack. I have three sets of 2.0 heads and the all have cracks. Once you get them welded up a complete valve job with new seats and you're in the $1000 range and they're just going to crack again. It's a shame that nobody is making new 2.0 heads with modern alloys that are more durable. Thank goodness we at least have AMC heads to build up as replacements. Anyone have any cracking issues with AMC heads?
So far I have yet to see an AMC head crack.
Seen them come back for service from track cars that ran over 1400* EGT's. Warped them and killed the valve job, but they didn't crack.
Seen them abused on CA busses with clogged catalytic converters that heated the heads so high it degraded the 1800* rated exhaust seats we install. Again, warped but not cracked.
They are very good castings, but the parts are garbage.
If I ever do this again I will likely go the no 2.0 head.
Posted by: HAM Inc Aug 17 2016, 02:50 AM
QUOTE(Mblizzard @ Aug 16 2016, 06:28 PM)
QUOTE(HAM Inc @ Aug 16 2016, 04:12 PM)
QUOTE(lonewolfe @ Aug 16 2016, 02:27 PM)
I think the original 2.0 heads are no longer worth the money to repair. They always seem to crack. I have three sets of 2.0 heads and the all have cracks. Once you get them welded up a complete valve job with new seats and you're in the $1000 range and they're just going to crack again. It's a shame that nobody is making new 2.0 heads with modern alloys that are more durable. Thank goodness we at least have AMC heads to build up as replacements. Anyone have any cracking issues with AMC heads?
So far I have yet to see an AMC head crack.
Seen them come back for service from track cars that ran over 1400* EGT's. Warped them and killed the valve job, but they didn't crack.
Seen them abused on CA busses with clogged catalytic converters that heated the heads so high it degraded the 1800* rated exhaust seats we install. Again, warped but not cracked.
They are very good castings, but the parts are garbage.
If I ever do this again I will likely go the no 2.0 head.
They're not cheap, but they are spectacular, more powerful and beefier than the O.E. castings.
Posted by: Mblizzard Aug 17 2016, 06:06 AM
QUOTE(HAM Inc @ Aug 17 2016, 12:50 AM)
QUOTE(Mblizzard @ Aug 16 2016, 06:28 PM)
QUOTE(HAM Inc @ Aug 16 2016, 04:12 PM)
QUOTE(lonewolfe @ Aug 16 2016, 02:27 PM)
I think the original 2.0 heads are no longer worth the money to repair. They always seem to crack. I have three sets of 2.0 heads and the all have cracks. Once you get them welded up a complete valve job with new seats and you're in the $1000 range and they're just going to crack again. It's a shame that nobody is making new 2.0 heads with modern alloys that are more durable. Thank goodness we at least have AMC heads to build up as replacements. Anyone have any cracking issues with AMC heads?
So far I have yet to see an AMC head crack.
Seen them come back for service from track cars that ran over 1400* EGT's. Warped them and killed the valve job, but they didn't crack.
Seen them abused on CA busses with clogged catalytic converters that heated the heads so high it degraded the 1800* rated exhaust seats we install. Again, warped but not cracked.
They are very good castings, but the parts are garbage.
If I ever do this again I will likely go the no 2.0 head.
They're not cheap, but they are spectacular, more powerful and beefier than the O.E. castings.
I looked into them so I know. Really was not planning on this change but I think I will plan for the expense.
Posted by: malcolm2 Aug 17 2016, 06:47 AM
So is everything back together? Jack stands back in the tool box?
Posted by: HAM Inc Aug 17 2016, 08:03 AM
QUOTE(Mblizzard @ Aug 17 2016, 05:06 AM)
QUOTE(HAM Inc @ Aug 17 2016, 12:50 AM)
QUOTE(Mblizzard @ Aug 16 2016, 06:28 PM)
QUOTE(HAM Inc @ Aug 16 2016, 04:12 PM)
QUOTE(lonewolfe @ Aug 16 2016, 02:27 PM)
I think the original 2.0 heads are no longer worth the money to repair. They always seem to crack. I have three sets of 2.0 heads and the all have cracks. Once you get them welded up a complete valve job with new seats and you're in the $1000 range and they're just going to crack again. It's a shame that nobody is making new 2.0 heads with modern alloys that are more durable. Thank goodness we at least have AMC heads to build up as replacements. Anyone have any cracking issues with AMC heads?
So far I have yet to see an AMC head crack.
Seen them come back for service from track cars that ran over 1400* EGT's. Warped them and killed the valve job, but they didn't crack.
Seen them abused on CA busses with clogged catalytic converters that heated the heads so high it degraded the 1800* rated exhaust seats we install. Again, warped but not cracked.
They are very good castings, but the parts are garbage.
If I ever do this again I will likely go the no 2.0 head.
They're not cheap, but they are spectacular, more powerful and beefier than the O.E. castings.
I looked into them so I know. Really was not planning on this change but I think I will plan for the expense.
You won't regret it!
Posted by: Mblizzard Aug 17 2016, 02:47 PM
QUOTE(malcolm2 @ Aug 17 2016, 04:47 AM)
So is everything back together? Jack stands back in the tool box?
You know how hard it is to get a 914 off jack stands!
Got it started (on jack stands) for a moment to verify it runs. Still have to replace the CV boot I ripped somehow and put the shift linkage back in.
Looking at the head it is clear it got too hot. So I am installing a Dakota digital cylinder head temperature sensor as well.
I took some extra time and tried to neaten a few things up as well.
Posted by: Racer Chris Aug 18 2016, 06:13 AM
QUOTE(Mblizzard @ Aug 17 2016, 04:47 PM)
Still have to replace the CV boot I ripped ...
I didn't ship anything the last couple days so its still on my desk.
Posted by: Mblizzard Aug 18 2016, 06:30 AM
QUOTE(Racer Chris @ Aug 18 2016, 04:13 AM)
QUOTE(Mblizzard @ Aug 17 2016, 04:47 PM)
Still have to replace the CV boot I ripped ...
I didn't ship anything the last couple days so its still on my desk.
No issues Chris. Wont have time to wok on it until next week anyway. But it is still a great thing to have vendors that don't judge your mistakes. It took a lot of effort to rip a CV boot.
Also it is great to be able to reach out and get what you need. Thanks for all of your help. The Evo will sound much better with all cylinders firing!
Posted by: stugray Aug 18 2016, 02:04 PM
QUOTE(Mblizzard @ Aug 18 2016, 06:30 AM)
It took a lot of effort to rip a CV boot.
Let me guess: Jacking the engine up with the axles touching the top of the trans??
Posted by: Mblizzard Aug 19 2016, 07:47 AM
QUOTE(stugray @ Aug 18 2016, 12:04 PM)
QUOTE(Mblizzard @ Aug 18 2016, 06:30 AM)
It took a lot of effort to rip a CV boot.
Let me guess: Jacking the engine up with the axles touching the top of the trans??
We have a winner!
Cant tell you how many times I have taken an engine out of a 914 and put it back with no issues. But the whole process seemed to be jinxed this time.
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