How to Shell Blast Intake Valves - SS
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Joined: 05-01-2014
Posts: 8,499
From: California
22. I performed another leak down test here. My prior readings - cylinders 1-3 had 2-4% leakage, and cylinder 4 had 23% leakage(crankcase and intake). Now cylinders 1-3 have 2% leakage and cylinder 4 has 5-6% leakage (crankcase). These results are better than I expected. I forgot to take pictures of the clean ports and valves. They are not as clean as the BMW machines get them, but they were pretty good.
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Joined: 01-16-2017
Posts: 384
From: Ohio
12. Again, keep alternating between scraping, vacuuming, and blasting. Once you get those 3 cylinders, 6 ports and valves, as clean as you think you can, spray some Berryman's B-12 in the port, and you will see the spots you missed. A little more scraping and vacuuming. Spray a little more Berryman's and use those brushes I referenced above, with a drill or impact driver, or even by hand if you don't have these power tools. I used the nylon brushes, so as not to scratch anything.
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Joined: 09-15-2013
Posts: 406
From: Cleveland. Ohio
THIS IS THE ABSOLUTE WORST PIECE OF ADVICE ON THE PLANET FOR ANYONE DOING A WALNUT BLAST!!!!! Do NOT use Berryman's B12 (or any carb/throttle body cleaner for that matter) to assist removing gunk form the intake valves and ports! It just cost me an engine!!!!! (Grrrr!!!!) The can of Berryman's, nor this person, nor anyone else in this thread mentioned that carb cleaner melts plastic and rubber components. And I have only ever used carb cleaner for its intended purpose (i.e., metal carbs/throttle bodies), thus never had an issue with plastic/rubber degradation. Carb cleaner will leak past the valve seats, into the pistons, and then past the piston rings, to contaminate the oil and attack every bit of plastic and rubber in the engine. I finished blasting and everything looked great. I started the engine and it ran great for 10 minutes. Just as I was about to shut it down to change the oil, I noticed the rear main seal suddenly gushed oil all over the shop floor! Seal melted! I now have the engine torn down to the bare block in an engine stand to inspect and/or replace every seal and plastic component. Learn from this mistake and leave the carb cleaner locked away for your walnut blasting job!! (Grrrr!!!)
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Joined: 01-16-2017
Posts: 384
From: Ohio
Valve seals are not a true 100% seal. It's metal-to-metal (not rubber-to-metal, which would be a true seal). At the microscopic level, there are voids through which fluids can leak. Likewise for the piston rings on the cylinder walls. Not to mention, the walnut blast itself is intended to address gunk buildup, which could very possibly be on the valve seal faces, making the seal worse. Any amount of carb cleaner sprayed in the ports will puddle and slowly leak through, eventually making its way to the crankcase. The carb cleaner is toxic. It melted a plastic screwdriver handle that was lying in a damp rag. It melted the lens of my safety goggles from splatter. It melted the lens of my shop light. If you don't believe me, you can try it for yourself.
And no I'm not here to make false claims and degrade someone else. I'm here merely to share my expensive lesson with others, so they don't also do it. If you feel my claims are erroneous, that is fine. You may do as you see fit. But I assure you, you are playing with snakes and may get bit, like me.
And no I'm not here to make false claims and degrade someone else. I'm here merely to share my expensive lesson with others, so they don't also do it. If you feel my claims are erroneous, that is fine. You may do as you see fit. But I assure you, you are playing with snakes and may get bit, like me.
Senior Member
Joined: 09-15-2013
Posts: 406
From: Cleveland. Ohio
Valve seals are not a true 100% seal. It's metal-to-metal (not rubber-to-metal, which would be a true seal). At the microscopic level, there are voids through which fluids can leak. Likewise for the piston rings on the cylinder walls. Not to mention, the walnut blast itself is intended to address gunk buildup, which could very possibly be on the valve seal faces, making the seal worse. Any amount of carb cleaner sprayed in the ports will puddle and slowly leak through, eventually making its way to the crankcase. The carb cleaner is toxic. It melted a plastic screwdriver handle that was lying in a damp rag. It melted the lens of my safety goggles from splatter. It melted the lens of my shop light. If you don't believe me, you can try it for yourself.
And no I'm not here to make false claims and degrade someone else. I'm here merely to share my expensive lesson with others, so they don't also do it. If you feel my claims are erroneous, that is fine. You may do as you see fit. But I assure you, you are playing with snakes and may get bit, like me.
And no I'm not here to make false claims and degrade someone else. I'm here merely to share my expensive lesson with others, so they don't also do it. If you feel my claims are erroneous, that is fine. You may do as you see fit. But I assure you, you are playing with snakes and may get bit, like me.
