Slow Guy

In a previous thread I mentioned how during my initial SAI port cleaning I was able to get good solvent flow through the ports in cyl’s 4 – 6 but that only 20% (apx.) of the solvent went to cyl’s 1-3, with nothing coming out of cyl #3. I tried running wire and also tried snaking the carb cleaner tubes up port 3 but it still didn’t clear the port. I needed a way to isolate the solvent & air flow to the 1 – 3 bank.

Link

I found that I was able to remove the flare nut that holds the aluminum tube to the 1 – 3 bank of cyls. at the SAI manifold (see photo). I had already made an “L” shaped fitting that consisted of a 3” piece of ½” ID vinyl tubing, a “L” shaped brass (copper?) fitting and another section of vinyl tubing apx. 12” long and 3 small hose clamps. There was enough flex in the aluminum piping that went to the 1 – 3 cyl. Bank that I could put the short section of vinyl tube over the aluminum pipe and fasten a clamp. I was now able to force all solvent and air to the 1 – 3 cyl bank.

Unfortunately still no solvent came out of cyl #3. In previous threads Chris Walrod had mentioned taking a piece of small pipe to force air UP into the ports so that is what I set about to fabricate. Unfortunately Home Depot didn’t have any short sections of ¼” copper pipe so I had to buy a “refrigerator icemaker supply kit” which comes with about 15 ft. of 1/4 “ copper pipe and a bunch of fittings. I only used about 10” of the copper tube and bent one end so that it would go around the valve stem and up into the SAI port from the exhaust manifold side, it fit pretty darn well. I had a fitting for my compressor nozzle that fit very well into the ¼” copper tube but the air still didn’t clear cyl #3.

Amfab/Andrew had used bass guitar strings attached to a drill to roto-router out their clogged port but since I don’t have a guitar I needed something else. I found I had a flexible extension that went on the end of an old Ryobi dremel type tool that had the same type cable as the drive cable for a weedwacker, only smaller. (see photo) That cable came right out and was strong but flexible. It was much longer than I needed so I cut it in half (still longer than I needed). I attached this cable to my Dremel tool (cordless drill batteries were too discharged) and fed the cable up into the ¼” copper tube that was inserted into the SAI port. This gave “support” to the cable so when the Dremel was on the cable didn’t flex all over. It took about 5 min. with the Dremel /cable and the cable seemed to move only about ½” but it did clear the port. I didn’t know this for sure until I squirt more solvent and compressed air into my plumbing attachment in the engine compartment but this time solvent came out of all 3 cyl ports!!!!

This AM I continued the process using Berryman's B-12 and all 3 cyl's on the left bank seemed to flow quite well. I then reattached the aluminum tube to the SAI manifold, reattached my original PVC to vinyl tube cleaning fitting and finished off the rest of the can of B-12 (alternating a 3 sec. squirt w/ a couple sec's of compressed air) into the combined 6 cyl's and all 6 flowed well. I then ran compressed air only for about 4 min. to try and dry the ports a little bit. Now I'm in the process of buttoning the system back up.

Slow Guy

I'll try and take a better photo of the 1/4" copper pipe inserted into the SAI port above the valve stem in the exhaust tomorrow.

Garth S

Nicely done! ( love the smell of Hoppe's #9 - it might even make a SAI flush enjoyable )

Amfab

That was me with the bass strings. But I got em to go several inches up.
here is the Thread

Slow Guy

Good, now I know whom to give credit to. I got the cable to go up several in. but from the point I first hit resistance to the point I stopped and solvent was able to come out the port was only about 1/2 in.

I have a couple extra pics. to add but I'll have to do that tomorrow.

Slow Guy

Adding photo of the 1/4" copper pipe in the SAI port hole and also another photo of the tools I used/made.

Slow Guy

FWIW, my car has just over 70k mi. and had NOT thrown a CEL.
The SAI valve looked like it had been changed in the past but when I don't know. However it was pretty crappy in there, I'll be replacing it at 15 - 30k increments from now on. It had a crushwasher under the valve and I used antiseize and a new crushwasher on the new valve.

The task is not difficult but it is quite involved. Prior to undertaking this procedure I was concerned about how irritating the job of removing/replacing the manifold/heat exchangers would be but that portion of the task was very easy and realigning the manifold to the cat was not difficult at all.

So to any that are contemplating the task I say go for it and I hope for your success.

1pcarnut

Bill, very creative, I applaud you for the ingenuity and thanks!

Had a thought, that cable looks about the size of a speedo cable, so that might also be an alternative "drill".

groovzilla

perhaps when the time comes you can perform my heart triple bypass??

Slow Guy

There are a few Doctors in my family but I'm not one of them. I'd be happy to consult w/ your doctor (for a fee of course) if you'd like.

Seriously, thanks for the comments but it was folks like Chris Walrod and Amfab/Andrew that got me on this track.

BTW, the cable I used was from a cheap Ryobi dremil extension, the cable just pulled right out but maybe something like a motorcycle speedo cable would work too (in addition to Andrew's bass guitar strings).

henkinc

Bill - out of curiousity, why did you undertake this task if you had no CEL thrown? Not just idle question since my CEL throws regularly for 10k miles (61k on car, slightly better than 1000 mi/qt of 20-50) and my wrench failed to dislodge any of the ports' gunk this year when he tried. Did not have all your tools, but smilar approach. Hence my build up may be worse than yours. Fabulous write up, btw.
Charlie
97 triple black cab, ROW M030, strut bar, HIDs

Rick Lee

Did you have to use an oxy/acetalene torch to get the heat exchangers off?

Slow Guy

I did it on that car for preventative measure, and glad I did. I didn't want to wait until it was fully clogged to do it. I've since sold that car to Vincer who's local and keeps me up with any issues he has with it and so far there have been no additional issues with the SAI system.

The replacement 993 had 31k mi. on it when I did the same thing to it. It was worth doing to this car too. However I did not take the tubes from the manifold off this time, I did everything from the bottom. (I made a extended sprayer mini tube setup on a can of Berryman's B12 to get up into the ports.) I judged by how far the cable would go up whether it was clear. I will however do the flush from the top down at about 50k mi.

I would highly recommend using the bike brake cable for this task.

No. I had no problems removing the exhaust system on either car. I did however use new nuts/bolts and used anti-seize them when I reattached everything.

henkinc

Nor did my wrench have to use special measures to get the exchangers off. I observe, however, that at 60k miles and at least 10k driven with the problem, I may have "baked" my clogged ports in more than Bill. Bill - how many miles per qt did you get on the older car and on the current 993?Neither of which threw CELs.
Charlie

Slow Guy

Charlie, neither of my 993's used much oil at all. I don't think I ever added oil to either of them between oil changes. Oil changes are annual and mileage between them varies but usually between 2,500 mi and 6,000 mi. so my oil consumption has been very low by 993 standards.

Knock on wood.