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Discussion Starter #1
Hello to all
I own since 20 years a 2.2TII Shelby five speed with now approx 120.000 miles on it. The car runs very fine and is well serviced. But since two months I have trouble with it: after I had parked at a supermarket for two minutes and wanted to start again the machine was running only on 3 cylinders. I came back to my close home slowly and found then a follower popped out in the head and the valve stuck in the open position:



A light knock with the plastic handle from a tool let it pop up. I replaced the follower, checked the compression, all was fine, all cylinders had the same pressure. So I did a fresh oil service and got back on the road. Then 400 miles later I had the same: a short stop with a warm engine was enough to let the follower pop out while starting up. In the thread "'88 Shelby Z singing a different song..." someone mentioned a popped oft follower and said that this happens sometimes... What is to do in this case? I don't have an idea, whats to do now, since last time I drove again 200 miles, 50 of them with a speed of 100 mph :)
Thanks in advance to every useful hint!

 
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The best permanent fix is to rework the head - new valve guides pressed in, new valves, resurface the seats, etc.And Welcome to Allpar!
 

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Discussion Starter #3
The head was reworked 15000 miles before, all new guides, valve seats grinded, fresh seals, new gasket etc.

Thanks for welcome, this is my thirst try in an US forum. In Germany we have the LeBaron.de forum, but the most are V6 there, nobody knows the special fourbanger stuff.
 

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Ratte said:
The head was reworked 15000 miles before, all new guides, valves grinded, fresh seals, new gasket etc.
How about the springs? were they checked or replaced?
It is rare to have a valve stick like that on a 2.5. I'm guessing that either an out of spec guide or a badly carboned valve stem is the culprit.... and it could possibly be a bad spring.
 

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Discussion Starter #5
I think the springs were checked, the rework was made by an authorized chrysler dealer. But I can not guarantee it, it is years ago.
I'm planing now to put out the spring, check it and check the valve whether it is freely turnable. What do you think?
@John: Why do you make a difference between 2.2TII and 2.5 in this case? Do 2.5 valves stuck more often?
 

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Ratte said:
I think the springs were checked, the rework was made by an authorized chrysler dealer. But I can not guarantee it, it is years ago.
I'm planing now to put out the spring, check it and check the valve whether it is freely turnable. What do you think?
@John: Why do you make a difference between 2.2TII and 2.5 in this case? Do 2.5 valves stuck more often?
Actually I didn't read that yours was a 2.2 Turbo until I just re-read the thread. My bad. There are a few differences in the head IIRC, but I don't know if it includes the guides or valves or springs. Is it possible that the re-work had unintentionally used some parts from a TBI setup that might differ slightly?

I just don't recall that problem coming up often on this board. I recall only one other poster with the exact problem.
 

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You need to replace the lifters. (Hydraulic lash adjusters)
I have had this happen on 2 cars.
Replaced all 8 lifters in each car and never had a problem since.
Had one that flew off and actually cracked a valve cover.
Head was not damaged somehow.
 

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It may also be that the valve sticking down is taking the spring tension off of the follower and when the cam rotates to the low side the follower can slip out.
I would try to determine the cause of the valve sticking as under no conditions should the valve stick open. If the lifter collapses it could also cause the follower to come free but I think the valve sticking may be the primary cause.
 

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I have seen a few cases where a loose valve seat causes this problem. The valve seat falls down but will sometimes snap back in place for a while making the problem intermittent. Something to consider.

Thamks
Randy
 

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Discussion Starter #10
Randy: this idea I had, too. But my mechanic, with whom I discussed that, meant the valve would not snap up so easy then, cause the seat rings are pressed in normaly really strong. But I'll try to have a look into the cylinder through the plug hole with a endoscopic camara. Perhaps I can see something.
Thank you all for your hints!
 

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Ratte said:
Randy: this idea I had, too. But my mechanic, with whom I discussed that, meant the valve would not snap up so easy then, cause the seat rings are pressed in normaly really strong. But I'll try to have a look into the cylinder through the plug hole with a endoscopic camara. Perhaps I can see something. Thank you all for your hints!
I know it sounds unusual but I have personally experienced this situation. I'm not saying for certain this is your problem but it's something to consider. After it happens a time or two the seat will eventually not pop back in position but end up crooked and the valve stays open.

Thanks
Randy
 

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Randy is on the right track. As an engine builder, I can state categorically that the valve seats can and do sometimes come out of the head. This would require the re-fitting of another valve seat and grinding of the new seat. It would only be necessary to do the one (1) valve seat. I have had machine shops do this for me over the years.
 

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Discussion Starter #13
Getting back to all the helpful members, I have now an update to my issue.

Since I've posted last time, the car did run fine till yesterday, without any problems approx 1000 miles. I didn't tread it, but I also didn't pamper it.
Then yesterday, of course in the evening in a heavy snow storm, I drove on the highway with approx 65 mph and felt the car slowing down. I knew in that moment what happened and fortunately I was only a 5 minutes drive from home.
Today I started the investigation. I took off the valve cover and it looked like the last two times. Then I unscrewed the spark plug and explored the combustion chamber with an endoscope with a small mirror. The results you can see on the pictures (please excuse the bad quality, but I only have two hands and my camera is broken)
On picture one the valve is without follower, stuck on the halve stroke, but on the picture you can see the edges of the seat ring and of the valve are on the same level.


On picture two I inserted the follower and turned the cam to the max stroke of the valve, now it is open, but it looks like the edges of ring and valve do not align.


On picture three you can see, how far the ring is out of the surrounding surface in the chamber.


By the way, now it is clear what's wrong, and what's to do now. I'll add new pictures, when the head is off.
Thanks
 

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Discussion Starter #14
Today I took off my cylinder head to replace it. Fortunately I've got a freshly reworked, never used head at ebay for a good price, so I can now get my Daytona back on the road again. I've planed to give that old head to a specialist for replacing that seat ring, but now I recovered that there is a crack in every chamber between the valves. What do you think, does that matter? Is it usable or is it scrap. I was happy to have a spare head, cause my LeBaron has the same engine.
As the head was out, I discovered a long crack in the sheet metal from the bulkhead. I'm a bit scared, is that a known issue at Daytonas?



As the head was out, I discovered a long crack in the sheet metal from the bulkhead. I'm a bit scared, is that a known issue at Daytonas?
It is starting at the drain hose from the air-condition and approx 12 inch long. :angry2:

 

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Interesting crack. I would not say it is common, haven't seen or heard anyone else have this issue. I would suggest drilling a small hole on each end of it to prevent it from continuing, then weld it back up carefully. Sounds like you intend to keep the car, might as well repair it correctly. Make sure anything flamable is removed from the back side.

As far as the head goes, one of the common things is the cracking. It can be ground out, aluminum welded, then remachined/ground out, new seats installed. Before you go installing that new head, if you look at your picture, get rid of all the sharp edges inside the combustion chamber for more power and better burn. You can see the wash of fuel on the quench area and shrouding on the intake valve, and how it is ckeab ir black right along the sharp edges. Rounding those edges allows the flame to travel into the quench area and produce power and torque, and burn even cleaner. Just stay inside the fire ring and do the whole combustion chamber. It is worth the couple hours to do this, in this case sanding rolls, round hand file, or my favorite a carbide burr cutter on a dremel tool (in your case) will show big improvements across the board. Round the edges to the fire ring on the sides, and about the roundness of the mouse wire on your computer for good results.
 

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A few other members have reported a crack there. I'd strip the interior and have it welded.

The heads often have a small crack between the two valves in each cylinder, but between cylinders is not common, never heard of it. I would not use it in that case.
 

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Discussion Starter #17
Dana: interesting hint with that rounding edges. I just thought about it, back then when the car was running, but now there I have the chance to do it with very little effort, ...it was just out off my mind. Thanks! And yes, I want to keep it. I own it now 20 years and I still enjoy driving with it.

Bob: your right, there is only a crack between the two valves in each cylinder, not between cylinders. So it is still usable?

The bulkhead crack I'll do someday later, then I overhaul the body. For the moment my goal is to get it mechanically sound.
 

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Dana's advice is good, drill holes at either end of the crack ASAP to stop the propagation for now, and weld as soon as practical.

The head is still usable if it doesn't leak. I'm told you can have it pressure-tested or leak-tested. If it passes, the cracks are harmless. I'm told nearly all of these heads have that, although I wasn't able to see them on mine.
 

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Hemi-Dude said:
Randy is on the right track. As an engine builder, I can state categorically that the valve seats can and do sometimes come out of the head. This would require the re-fitting of another valve seat and grinding of the new seat. It would only be necessary to do the one (1) valve seat. I have had machine shops do this for me over the years.
Seems like the diagnosis was confirmed!!

Thanks
Randy
 

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Mine had the same cracks in both the head and firewall. My head passed a pressure test and was fine.

Glad to hear mine isn't the only one with the firewall crack.
 
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