AFM Piston Soak / Top Cleaner

[77mercury77]

So GM has a TSB for Trucks with AFM made before 2010 to replace the valve cover with a new revision, add an AFM shield in the oil pan and to do a hot piston soak with their top cleaner.
I have done both the valve cover and the AFM shield on my 2010 escalade about 25K miles ago however I am still getting oil and sludge on my spark plugs in cylinders 1 and 7.

Any one here have experence with the performing piston soak? Is there an issue with only doing the cylinders that have oil fouling? Any tips on the process? I have the solution coming in and im gonna do it this weekend as a last attemp before doing more serious work.

 

[iamdub]

So GM has a TSB for Trucks with AFM made before 2010 to replace the valve cover with a new revision, add an AFM shield in the oil pan and to do a hot piston soak with their top cleaner.
I have done both the valve cover and the AFM shield on my 2010 escalade about 25K miles ago however I am still getting oil and sludge on my spark plugs in cylinders 1 and 7.

Any one here have experence with the performing piston soak? Is there an issue with only doing the cylinders that have oil fouling? Any tips on the process? I have the solution coming in and im gonna do it this weekend as a last attemp before doing more serious work.

Hopefully, you've helped the oil consumption and it's just stuck rings and not permanent damage. Get a catch can yet?

@donjetman completely resolved his oil burning/stuck ring issue by performing the TSBs and (IIRC) two rounds of the top end soak. He also used a cheaper cleaner (Motor Medic? I can never remember.)

Maybe he'll see the tag and chime in soon. In the meantime, search his user name for his thread. If I find it, I'll link it here.


*EDIT* I found his thread: https://www.tahoeyukonforum.com/threads/rear-main-seal-job-pan-etc-07-yukon-denali-6-2.108334/

 

[justchecking]

Scotty Kilmer has a recent video where he is trying a new engine flush which he thinks appears to work pretty well.

 

[77mercury77]

Thanks guys, great finds!

Also regarding the catch can I see two intake manifold to rocker cover connections. The driver side is the one with the updated pcv but the passenger side is as built. Do I get two cans or just attach a two port can to the D/S? Any reccomendations for a brand?

 

[Bill 1960]

Not this engine, but I have successfully cleaned stuck rings in other engines by pulling the plugs and top soaking the pistons. I’d give it a shot.

 

[donjetman]

Yes I did the soak w/Gunk brand Motor Medic (autozone). I did the soak over a period of 2 days, a longer period of time than what the TSB called for. Pulled all the spark plugs, squirted some into each spark plugs hole with a turkey baster. Waited many hrs, cranked the engine 90* by hand w/harmonic balance bolt, squirted more into each hole. Did this 4 times. I had the drain plug out the whole time. Spun the engine over with the starter before putting the spark plugs back in. After getting it all put back together. Ran it for a few hundred miles then changed the oil and filter again. Today, 40k miles and 3+ yrs later, it's still dry as a bone underneath, doesn't consume any oil, and the catch can doesn't collect much of anything.
Here's a thread I did on what the spark plugs looked like: https://www.tahoeyukonforum.com/threads/sparkies-no-beno.108579/

 

[77mercury77]

Thanks man that's exactly the intel I needed. Which cylinders were gunked up? Did you do the soak hot/warm?

 

[donjetman]

Thanks man that's exactly the intel I needed. Which cylinders were gunked up? Did you do the soak hot/warm?

All eight of mine were bad. I did the soak cold. The nasty spark plugs pictured in that thread, I cleaned, gapped (.040"), and ran for another 37k miles.

 

[iamdub]

Thanks guys, great finds!

Also regarding the catch can I see two intake manifold to rocker cover connections. The driver side is the one with the updated pcv but the passenger side is as built. Do I get two cans or just attach a two port can to the D/S? Any reccomendations for a brand?

Unless we're talking about different things here, there's only one PCV circuit you need to filter. There's a hose that runs from the air intake tube to a port on the passenger side rocker cover, just behind the oil fill neck. This is the inlet for fresh, clean air to go into the crankcase. The outlet for venting out the positive pressure of the crankcase (the oily air) is the port on the back of the driver side rocker cover. It is routed from that port and straight into the intake manifold. This is the circuit you need to filter, which is what the catch can is for. You route the outlet from that rocker cover port to the inlet of the catch can, then from the outlet of the catch can to the inlet of the intake manifold. If you have oil coming out of that passenger side port, then your crankcase is getting overly pressurized and possibly clogged on the outlet side. This would make it act like someone with a bowël obstruction that continues to eat, so the puke up half-digested food.

The cans all do pretty much the same thing from the $15 ones on Amazon and ebay to the $200+ "big name performance" brands. I have a catchcans.com one on my Tahoe and I installed a $20 one from Amazon on my brother's truck. Both function the same way, just different shapes and capacities. I added a stainless steel scrub pad to each to increase their efficiency. With the cheaper ones, the main thing to watch out for is the materials used on the inside. Some use mild steel for the baffle instead of aluminum or stainless. You definitely don't want steel. Most all have similar capacities. If your engine is moving a lot of oil through the PCV system, you're gonna need a large capacity can or just drain yours often. The cans with a dipstick are a bit of a gimmick. I suggest getting one with a 1/4-turn valve on the bottom for easy draining. Don't get one with a breather filter since that would be a vacuum leak and cause drivability issues and DTCs.

 

[77mercury77]

Thanks all for the help. If anyone is interested in doing this here are my notes:

I ran a hot piston soak using ACDelco's 10-3015 /19355198. This is supposed to be the current version of the fluid called out in the TSB. Its about #35. Not as serious as the original formula but the original is discontinued and selling around $160 a can.

To make life easier I used a 100cc graduated syringe with about a foot of tubing. This let me measure the amount i put in as well as remove the fluid when done.

Cylinder #1 kept all the fluid for the three hours whereas Cylinder #7 drained to the case.

I used a 15/16 socket to rotate the engine clockwise out of TDC via harmonic balance nut. I also disconnected all the coil packs and the 26# fuse (FCSM) to cut the injectors. This let me spin the engine using the starter to get all the remaining fluid out. Even after sucking the fluid out it still got everywhere so pack the bay with a towel.

New oil and new plugs and added a Range AFM disabler.

The last thing I am doing is an oil catch can. Can any one help me with the manifold connection? My stock tube is hard plastic to the plastic elbow. I think the elbow comes off with 1/2 turn? How did everyone else connect? Remove the plastic tube and use the stock elbow or a different fitting? Pic below