I am contemplating a SAI flush and am looking for recommendations on the
best fluid to use in the process. I've heard of using techron, lacquer thinner, BG 44K, etc. What's your experience???
Thanks!
Phil
best fluid to use in the process. I've heard of using techron, lacquer thinner, BG 44K, etc. What's your experience???
Thanks!
Phil
I have used techtron , and seafoam, cloggged up the ports with drain testers , left the fluid in over night.Then used my trusted brake cables with different lengths . Don`t forget that there is a vacuum hose next to the check valve when you change it. Good luck.
Don't think there is one definitive product - and all the above you mentioned have been recommended. I think the method is more important, if you use motorcycle brake cable on a drill, you can get a lot of the carbonized material out of the passages. Be patient, keep scraping out the ports. Don't forget there is a angle change between the cam carriers and the heads - see my article on pcarworkshop>
http://www.pcarworkshop.com/index.ph...e_SAI_passages
One note as well - do not use too much air pressure - you will risk blowing through the seal between the heads and the cam carrier, since that is an adhesive joint. Some people put 100+ PSI thought there, I would be cautious to do that much - mabye 60. Your call of course.
Cheers,
Mike
http://www.pcarworkshop.com/index.ph...e_SAI_passages
One note as well - do not use too much air pressure - you will risk blowing through the seal between the heads and the cam carrier, since that is an adhesive joint. Some people put 100+ PSI thought there, I would be cautious to do that much - mabye 60. Your call of course.

Cheers,
Mike
IXLR8
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Cheers,
Mike
Originally Posted by Mike J
One note as well - do not use too much air pressure - you will risk blowing through the seal between the heads and the cam carrier, since that is an adhesive joint.Cheers,
Mike
Mike, I was thinking about that aspect recently and what the solvent used might even do to that sealant.
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+1 on this. When I did my top end rebuild, this is the only stuff that would dissolve the carbon buildup on the pistons which is the same stuff clogging up the SAI. That carbon build up really hard, like rock hard.Originally Posted by flying_low
I'm partial to B-12 Chemtool Carb Cleaner.
You can buy B-12 Chemtool by the bucket. Be careful. It WILL take off paint.
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Totally agree - here is an example of one of the ports, not much sealant between the hole and the edge of the casting. Originally Posted by IXLR8
Mike, I was thinking about that aspect recently and what the solvent used might even do to that sealant.
I have no idea how solvent resistant the factory sealant under pressure is - that is Loctite 574 - but have included a part of the spec sheet for the product below - it shows that the sealant reduces in effectiveness by 25% with gasoline over a 100 hr period, so if nastier solvents it might be impactful. The good thing is when the flush is done, its perhaps maximum 24hrs since people may let it sit overnight, which is much less than the 100 hrs on the graph. Too bad we did not see what say 24hrs with B12 does ... maybe I need to run a test.

Cheers,
Mike
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That sounds like paint stripper which is what I have been using to remove carbon since the 80s. Cheap and readily available.Originally Posted by axl911
You can buy B-12 Chemtool by the bucket. Be careful. It WILL take off paint.
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I have no idea how solvent resistant the factory sealant under pressure is - that is Loctite 574 - but have included a part of the spec sheet for the product below - it shows that the sealant reduces in effectiveness by 25% with gasoline over a 100 hr period, so if nastier solvents it might be impactful. The good thing is when the flush is done, its perhaps maximum 24hrs since people may let it sit overnight, which is much less than the 100 hrs on the graph. Too bad we did not see what say 24hrs with B12 does ... maybe I need to run a test.
Cheers,
Mike
Exactly Mike.Originally Posted by Mike J
Totally agree - here is an example of one of the ports, not much sealant between the hole and the edge of the casting. I have no idea how solvent resistant the factory sealant under pressure is - that is Loctite 574 - but have included a part of the spec sheet for the product below - it shows that the sealant reduces in effectiveness by 25% with gasoline over a 100 hr period, so if nastier solvents it might be impactful. The good thing is when the flush is done, its perhaps maximum 24hrs since people may let it sit overnight, which is much less than the 100 hrs on the graph. Too bad we did not see what say 24hrs with B12 does ... maybe I need to run a test.

Cheers,
Mike
If I have to remove carbon, the first thing that comes to mind is paint stripper and I have no idea how it might affect the sealant, no matter how insignificantly. If anything, I would clean mine mechanically as best I can.
At 77,902 kms, my never-cleaned-so-far ports are so free flowing, I am not even going to bother cleaning anything. I will replace the check valve which appears done.
Would you happen to have the diameter of the port at the exhaust handy?


