Complete Misfire on Three Cylinders

[jonathanrussell]

In the head I built last summer I used Sealed Power ST-2034 seals. Too recent to say how they will do long term but so far so good. I chose them because they are a viton seal.

The seals I had sitting around that came in a few gasket kits just seemed kind of hard as a rock.

[S30Driver]

22 hours ago, jonathanrussell said:

In the head I built last summer I used Sealed Power ST-2034 seals. Too recent to say how they will do long term but so far so good. I chose them because they are a viton seal.

+1 on the Sealed Power seals.  I installed them 4 years ago, no issues thus far....

[Captain Obvious]

Thanks guys. I (think I) just nabbed the last 24 off rockauto. I need 12 for this engine, and 12 for my P79 when I get back onto that.

So, now that it may be too late.... Same part number for both intake and exhaust?

[Captain Obvious]

And, since no car good project goes along without complication, I've found another PO caused issue with my N47 head.

I had known for some time that a couple of my valve cover bolt holes were stripped out. Not the end of the world. And I also already knew that on one of them, my PO had tried to drill out the old bolt and missed. Hole was off center, half the steel bolt still stuck in there, crappy threads... The usual. Well, I decided that since I had the head on the workbench, I was going to do something about it.

Mistake.

I'm looking at the whole situation, and noticed that there is a chunk of brass way down in the bottom of the off center chewed up hole. I have no idea what that's all about, but I don't want it in there. So I start drilling it out.

Figured out what was going on there... When he drilled (half) the old bolt out, he drilled too deep, and actually punctured through into the water jacket below. AAARRRRRRGH!!!!! That chunk of brass was some sort of plug he stuffed down into there to seal the bottom of the hole back up.

So now I'm going to spend the next bunch of hours working on trying to fix that crap.      

[Dave WM]

I was playing with seals last night, after removing the valve (practicing using my valve spring depressor) I put some heat shrink on the end to cover the retaining slot, heated it up to form a nice seal installation tool to prevent nicking the seal when replacing. They sometimes come with those little candy stripe straws, I think the heat shrink works better, thinner, tighter fit and the shoulder created by the shrinking worked well.

Some interesting reading on the subject of seals, somewhere I read to NOT use assy lube just coat the valve stems with the oil you normally use. something about the assy lube gumming up. Seems unlikely it could be an issue but, for what its worth I read it.

compared the old seal to new Nissan OE, the old one had a noticeable larger hole that the stem fits into . It was somewhat stiffer than the OE seal as well, but still not what I would call too stiff. I was surprised to find is still pliable at all considering 43 years old.

[Dave WM]

3 minutes ago, Captain Obvious said:

And, since no car good project goes along without complication, I've found another PO caused issue with my N47 head.

I had known for some time that a couple of my valve cover bolt holes were stripped out. Not the end of the world. And I also already knew that on one of them, my PO had tried to drill out the old bolt and missed. Hole was off center, half the steel bolt still stuck in there, crappy threads... The usual. Well, I decided that since I had the head on the workbench, I was going to do something about it.

Mistake.

I'm looking at the whole situation, and noticed that there is a chunk of brass way down in the bottom of the off center chewed up hole. I have no idea what that's all about, but I don't want it in there. So I start drilling it out.

Figured out what was going on there... When he drilled (half) the old bolt out, he drilled too deep, and actually punctured through into the water jacket below. AAARRRRRRGH!!!!! That chunk of brass was some sort of plug he stuffed down into there to seal the bottom of the hole back up.

So now I'm going to spend the next bunch of hours working on trying to fix that crap.      

yikes... geez Louise, does it ever end :(

[jonathanrussell]

What a bummer regarding the valve cover bolt hole.

How do you think you are going to fix? Could have the hole welded up slowly so you don't warp the head, then drill, tap. I wonder if you re-tap and then seal the valve cover bolt threads does it matter....at least for a quick fix?

[siteunseen]

I have an N47 bare head. It's an early one with the spray bar and oiler cam BUT I've robbed that stuff for my E31. Cam, towers and valves.

If you are interested I'll get it down and send you some pictures.

[Reptoid Overlords]

Thanks guys. I (think I) just nabbed the last 24 off rockauto. I need 12 for this engine, and 12 for my P79 when I get back onto that.
So, now that it may be too late.... Same part number for both intake and exhaust?

I ordered the sealed power seals as well, and as far as I can tell, it's the same part number for both intake and exhaust.

I have a set of ITM engine componets seals that came with an entire gasket set at home, and all 12 valve stem seals look to have the same dimensions.

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[Av8ferg]

And, since no car good project goes along without complication, I've found another PO caused issue with my N47 head.
I had known for some time that a couple of my valve cover bolt holes were stripped out. Not the end of the world. And I also already knew that on one of them, my PO had tried to drill out the old bolt and missed. Hole was off center, half the steel bolt still stuck in there, crappy threads... The usual. Well, I decided that since I had the head on the workbench, I was going to do something about it.
Mistake.
I'm looking at the whole situation, and noticed that there is a chunk of brass way down in the bottom of the off center chewed up hole. I have no idea what that's all about, but I don't want it in there. So I start drilling it out.
Figured out what was going on there... When he drilled (half) the old bolt out, he drilled too deep, and actually punctured through into the water jacket below. AAARRRRRRGH!!!!! That chunk of brass was some sort of plug he stuffed down into there to seal the bottom of the hole back up.
So now I'm going to spend the next bunch of hours working on trying to fix that crap.      

Oh boy, you are finding all sorts of Easter Eggs in this engine. What’s next...this saga isn’t over I expect. Know when to hold them and when to fold them buddy! Hint hint!


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[Dave WM]

I would tap it, and use a something like a set screw with some red Loctite.

[jonathanrussell]

Another thought....

Does anyone make a thread repair insert (like time-sert) that is closed on the bottom of the inside?

Another thought....

You could change this one fastener to a stud and thread lock it in then tighten that one with a nut. That way the water passage is sealed and you are not ever removing it.

Edited July 12, 2019 by jonathanrussell
second idea