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Misfire when cold

I'd check the PCV valve/system first. You might get lucky.
If no joy, it's got to be bad valve stem seals, or piston rings.
(Maybe a stem seal has split or was installed incorrectly.)

Might also pull the plugs and see if one has been oil-fouled
more than the others. That'll at least isolate the problem.

That's a bummer to do all that work and then see smoke...

The symptoms sure seemed like bad valve seals - despite the heads being new, so I pulled the plugs today. Plugs #4 and #5 had wet oil on them, all of the others were dry. So I bit the bullet and pulled the driver's side valve cover (which unfortunately requires removing the upper intake, again!)

Looks like the valve seals on #4 and #5 have a tear in them, partially obscured by the (incorrect) timestamp:



No idea if these tears would be enough to cause the symptoms, but they need to be fixed regardless.

I've been practicing removing the valve springs and seals on my old cracked head using the Lisle 36050 kit. It easily removed the springs, but it was tough getting the intake one back on, and I couldn't get the exhaust one back on even on the bench. I feel like this would be impossible to do on vehicle. Any suggestions or tips to make this easier? Maybe try a different style tool?


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I've never seen the one you chose but then I happened upon a YouTube video by a guy that calls himself "Eric the car guy" - just linking the video because maybe maybe this will help? Also, read the comments, maybe that will help you edge your way over The Rubicon ;)


You could try this one if you have a Harbor Frieight close by. It's cheap enough that at $12 (and then a 20% off coupon) it's worth a shot.
Also, read the review comments for ideas on how to modify the tool to work for your application.
With a tool like this, it appears that you might have to have a good selection of vise grips, and maybe some heavy duty zip ties.

Link to Harbor Freight Coupons: Harbor Freight Coupon Database

Link: Universal Overhead Valve Spring Compressor


Good luck!

Thanks Dave! I got one of those jaw-type compressors like you showed, and it worked. Mine was an OTC-branded tool from Amazon but it looks exactly like that one.

Everything's back together. Unfortunately it still smokes. Not sure where else the oil could be getting in? Plugs #4 and #5 were the only oily ones, and I changed all 4 seals on those two cylinders.

Everything's back together. Unfortunately it still smokes.
Not sure where else the oil could be getting in?
Plugs #4 and #5 were the only oily ones, and I changed all 4 seals on those two cylinders.


Glad I could help! *high five*

Well, it seems like the last road to go down would be doing a dry & wet compression test -

Checked the plugs again and this time they were all dry. Then I decided I should check the other head and see if there was anything obvious with the valve seals.

This is what I found:


This is two separate seals. There was at least one more with damage.

I'm now waiting on another set of stem seals, I might replace all of them on this side - seems like a systematic problem with the part quality, or install. It's worth noting that the heads were bought pre-assembled with the valves, seals, and springs already installed.


I feel for you, brother! If it isn't the seals ripping on one side, now it's the seals folding over on themselves...

Say man - I'm guessing you're getting your new seals from Rock Auto - which ones have you settled on?

Also - to keep the valve from dropping in the cylinder, are you using the air fill method or? I've seen an number of methods mentioned on YouTube.

I had a pack of MAHLE/Victor-Reinz that came with the head gasket kit, but I messed up a few on the install, so I am buying a set of Fel-pro's.

To keep the valve from dropping, I moved the cylinder to TDC (or visually close to it, by looking into the spark plug hole). Then I used the hose from a compression gauge and my air compressor. If you do this, make sure you remove the air schrader valve in the compression hose or it won't work! The compression hose is designed to let air flow from the cylinder into the gauge, not the other way around. It doesn't take much air to keep the valve from falling - 20 psi was plenty. My air compressor is a smaller Craftsman oil-lube unit, 1.5 HP and it had no problem keeping up.

Happy to report that it's been a few months and no more blue smoke!

Looks as if that valve stem seal told over because of lack of lubrication on startup
I seen this before

I'm sure it's fixed by now lol