Lash Adjuster Replacement and Secondary Intake Valve Cleaning

[ViciousBlack97]

Well, with the paint shop appointment rapidly approaching on Wednesday, I decided to finally bite the bullet and fix the tap at startup, as well as install the MMR IMRC delete plates I've had sitting around for a while. I spent around 6 hours today, and I'm on the home stretch. Every secondary valve was disgusting, absolutely caked with carbon. On top of that, almost every lash adjuster that I pulled out had a bit of free play in it. Not like the springy feeling of the new adjusters, but slop of around 1/8th of an inch, with a dull thunk every time you moved the piston. A bonus surprise was that one of Cyl 8's exhaust valves had kicked it's follower. Who knows when, and who knows how. But I'm super pumped that it landed at the bottom of the head and any major damage was completely avoided. I'll post some photos mid-process, as well as some before and afters of the secondary valves. This is extremely tedious work, but I'd rather drop a socket on the sun baked fenders now instead of after it gets back from paint. If anyone wants some pointers/tips and tricks, feel free to post away. I'm all for making the next guy's life easier if they approach this same task.

Primary Intake Port

Secondary Intake Port prior to cleaning

Secondary Intake Port after cleaning

 

[boost88]

Did a good job cleaning them. I used a ton of carb cleaner, a small brush and a straw duct taped to my vacuum. Looks like you're on the right track.



Sent from my SM-G988U using Tapatalk

 

[Tillerman77]

Well, with the paint shop appointment rapidly approaching on Wednesday, I decided to finally bite the bullet and fix the tap at startup, as well as install the MMR IMRC delete plates I've had sitting around for a while. I spent around 6 hours today, and I'm on the home stretch. Every secondary valve was disgusting, absolutely caked with carbon. On top of that, almost every lash adjuster that I pulled out had a bit of free play in it. Not like the springy feeling of the new adjusters, but slop of around 1/8th of an inch, with a dull thunk every time you moved the piston. A bonus surprise was that one of Cyl 8's exhaust valves had kicked it's follower. Who knows when, and who knows how. But I'm super pumped that it landed at the bottom of the head and any major damage was completely avoided. I'll post some photos mid-process, as well as some before and afters of the secondary valves. This is extremely tedious work, but I'd rather drop a socket on the sun baked fenders now instead of after it gets back from paint. If anyone wants some pointers/tips and tricks, feel free to post away. I'm all for making the next guy's life easier if they approach this same task.

View attachment 1718399
Primary Intake Port
View attachment 1718400
Secondary Intake Port prior to cleaning
View attachment 1718401
Secondary Intake Port after cleaning
View attachment 1718402

Great work! How many miles on this engine and do you use an oil catch can?

 

[ViciousBlack97]

Great work! How many miles on this engine and do you use an oil catch can?

Thanks, it has 165000 indicated, probably more since the odometer gear was broken. I installed a JLT catch can around 15000 miles ago, and I get a pretty decent amount of oil from it.

 

[Tillerman77]

Thanks. I also run a JLT and it is nearly full at about 2K intervals on my PG 97.
Unrelated, but I also am running FRPP B springs with Bilstein HD all around (including quad shocks), MM C/C plates, MM FLSFC, MM solid rack bushings, MM 4 point K member brace and a Steeda 006-1STA adjustable rear sway bar.

 

[ViciousBlack97]

One more adjuster to go. As an aside, the driver's side exhaust valve train is nearly impossible to access. Add in the fact that I definitely wasnt pulling the hydroboost and it gets tight. I think I spent around 20 minutes on the rear most valve. You have zero room for error, especially with reinstalling the follower.

 

[ViciousBlack97]

MAJOR UPDATE: So, after getting it reassembled, it was running great. I had it holding at around 2500 rpm, waiting to come up to temp, when I heard a loud snap, and the car started running like crap. I shut it off immediately, and freaked the #$%^ out. After pulling the valve covers and cranking the engine a little more, I noticed that the noise was gone, and the SAME ROCKER ARM was now sitting in the bottom of the passenger side head. I think I'm going to reassemble without that follower and see how she runs, just to make it to the paint shop. After talking to the guys at Pro Dyno, sounds like there are 3 possibilities: Weak valve spring, bent/tweaked valve, or a failing exhaust seat. I know these 4 valve heads have been known to lose valve seats before, so I won't be surprised if that's the outcome. So, pending how it runs on 1 exhaust valve on the rear-most passenger cylinder, we'll get it to the paint shop, and then immediately over to Pro-Dyno for an evaluation. A side note: without that follower on the valve, that cylinder has perfect compression (~180psi).

 

[Tillerman77]

Oof - good luck!

 

[P49Y-CY]

i think brian fordtechmakuloco has a vid where he talks about broken followers, might be worth checking out. good luck with it