AAZ Gone Wrong

[WeekendMechanic]

Next up would be to pull the head.  Tip it up on its side so the intake and exhaust ports are UP.  Pour or spray some solvent into the intake and exhaust port of the offending cylinder.  If it pours right back out of one of the valves, you have likely found the culprit.  If there is only a tiny dribble or no leakage at all, then pull the piston/rod and inspect.  With 0 psi something should stand out.   

Your right valve for cylinder one is out of place there are all so cracks between all the valve ports


https://i.imgur.com/zPRumHe.jpg?1[/img]


https://drive.google.com/file/d/1sVLVrrBNOUxupq4elGqw8eaqKE0fmUuJ/view?usp=sharing
https://drive.google.com/file/d/1Ydw8Cf7h04irgfvgRPwwoooaJARpQEk4/view?usp=sharing
https://drive.google.com/file/d/1F22kXwHiOVjNLAXrvgksA7ZShX7GTi0a/view?usp=sharing

[libbydiesel]

Your pics won't show for me.  Error 404 from the links.

[ORCoaster]

404 error for me too.  Are you sure we the public can view your photos in the album? 



VW heads always have cracks between the valves on the head.  If less than the width of a dime they are fine.

[libbydiesel]

VW heads always have cracks between cylinders valves.  If less than the width of a dime they are fine.

FIFY   

I'm curious about the valve being 'out of place'.  I use Imgur for image hosting.  It is free has worked fine for the last few years (since the Photobucket debacle).


Well, I sure put a lot of thought into that one.  Could be why he has so little compression though.  We had a truck given to us at Habitat for Humanity with the 6.9 diesel in it.  The reason for the donation had to be that cracked cylinder because they obviously took the head off and discovered the reason for the loss of coolant.
Kind of poor of them to give it to us in that condition.  Cost about 6 K to fix.  But I drive it hard now and no problems. 

I am going to edit the post but acknowledge the mistake in wording here.

[WeekendMechanic]

I think these work..
As you can see the cracks are all the way across thicker than a dime there like that on all four.

https://imgur.com/EKM75nr
https://imgur.com/koPoYpi
https://imgur.com/zPRumHe

https://drive.google.com/file/d/1sVLVrrBNOUxupq4elGqw8eaqKE0fmUuJ/view?usp=sharing
https://drive.google.com/file/d/1Ydw8Cf7h04irgfvgRPwwoooaJARpQEk4/view?usp=sharing
https://drive.google.com/file/d/1F22kXwHiOVjNLAXrvgksA7ZShX7GTi0a/view?usp=sharing
« Last Edit: Today at 09:56:23 pm by WeekendMechanic »

[libbydiesel]

The cracks between the valves look fine.  I would even say they look small.  Can you really fit a dime into those?  However, the pic of the #1 valves looks like the intake valve is strangely offset to one side.  Pics are sometimes a bit hard to read.  Is that valve sealing correctly?

If that's the case, then I would check the seal of all the valves, replace the ones that don't seal well, hand lap them, reinstall the head and motor on. 

[WeekendMechanic]

Sorry I misread ok a dime can definitely not fit inside them ,I was thinking in length.
The valve is definetly not seated its sitting on the edge are you sure you cant see,its the one on the right.
I made a press a long time ago for pressing in wheel bearing it should come in handy again now.

[libbydiesel]

If the thickness of the cracks between the valves is thicker than the thickness of a dime then it would indicate a problem.  The cracks do not look that thick. 

The valve with the red arrow on the LEFT (#1 intake valve) looks bent or oddly offset to the side.

[ORCoaster]

Pop that sucker outta there and see if the keepers on top are out of their grooves or the valve itself has a bend to the shaft. 

Anything of note on the top of the piston for that valve?

[libbydiesel]

The one thing that still nags at me is that bent valves don't ever 'heal' temporarily.  You might be chasing a second issue if you get this one sorted. 

[ORCoaster]

Yeah, the statement that it started then went away is sort of disturbing.  That is the worst kind of problem to solve.  Kinda like an electrical problem that is there, then it is not. 

My thoughts are that when he first felt the piston hit the valve he forced it some.  That started the process and the car ran crappy for a bit.  Then the valve reset itself some and ran ok for a while.  Once it got heated and maybe got some RPM's going the valve failed to the point it is at now and the car really doesn't run well at all. 

Poor valve seal would sure explain the lack of compression.

[WeekendMechanic]

The one thing that still nags at me is that bent valves don't ever 'heal' temporarily.  You might be chasing a second issue if you get this one sorted. 

Once again Libbydiesel your intuition is correct!
The cause is a bolt in the cylinder #1 intake port, I`m not going to state how it got there, lets just take solos in the pride that I`m an idiot.Again i`m not going to say I`ll let you use your imaginations.



I used a press on the spring retainer and it poped the collars free to its original position,it was quite stuck.
Now what should I do?
Do you guys think I should replace the valve?
I used a straight edge on the stem of the valve and its still straight can and should I use it?
What about the valve guides should I pop them all out and insert new ones,lap in the valves and insert new oil seals?The offending valve is quite wobbly bentley says play should be no more that 1.3mm it seems to be just about that much I have not taken the other valves out yet to compare, keep in mind this is just a 100,000 mile motor.

[libbydiesel]

I would certainly replace that valve.  IMO, saving a few dollars right now is not worth risking the head of the valve falling off later from it being weakened by tapping onto the seat at an abnormal angle. 

With the head out, I would also check the other valves to make sure they are sealing well.  Tip the head so the ports are facing up and spray or pour some solvent or penetrating oil into the ports.  Watch on the combustion side for any leaks.  If there are any leakers, then hand lap all 8 and replace the valve stem seals.   

[ORCoaster]

Let's say that based on the 100 K miles and the readings on the other three cylinders the fix should be minimal now. 

You have the valve out, right?  So that would allow you to at least lap the seat on the head.  That nut is harder than aluminum so did it leave a mark?  I would not expect the valve to be bent by what has been determined to be the problem here.  It was just pulled down to the extent of travel and stayed there.

To be safe I think I would buy a new valve and some seals but not mess with the guides.  I never have good luck taking those seals off without damaging them but then I don't have those special pliers for the job either. 

While you have the head off measure the piston protrusion and buy the proper head gasket for the measurement you get.  You might be surprised to find your old one was a bit thick for the job. 

Then clean it up real good and reassemble and turn it over a few times by hand and if OK try the starter. 

Best of luck.

[WeekendMechanic]

Orcoaster is right the psi readings on the other cylinders are solid.
Thank you both.
I will buy a new valve and lap it in, along with new oil seals, I think thats all that needs to be done for a solid motor again.
I will keep in touch....