Cleaning a TDI Intake

Shortly after I posted my last entry, I cleaned the intake manifold from the TDI. Removing the EGR and the intake was very easy, actually. the only trick was not shaking it on removal - you don't want any soot particles to fall into the combustion chamber. Now, you'd think the engine gets rattled all the time just running, and there's pressurized air running through there, so "how could a chunk of soot just fall into the intake?" I don't know, I'm just doing what the mechanic-man said: don't let any chunks fall into the head. I ran a quick vacuum against the head to make sure I was clean, and cleaned up the exposed head with some solvent. Nice and shiny now.

Cleaning the intake was a dirty job. First, dug around with an assortment of screwdrivers and chisels, getting as much of the gunk out as I could. Then, I reamed it out with a short stretch of cable attached to the end of my drill. If you're thinking of doing this, get a stretch of vinyl covered cable about 18" long and cut about 3" of the cover off the end. Home Depot sells 2 kinds of cable and I suppose both could work. I used the thicker one, but I don't think it makes much difference. Anyway, thread the cable through a short section of steel pipe. I used a 6" stretch that I had lying around for when I eventually build my BioDiesel reactor. Using the pipe as a handle, you move the cable around the inside of the intake, being careful of the drill speed. I had the cable run a little too fast a couple of times and it almost bit me. Do this job in disposable clothes and put the intake inside a cardboard box when you're running the reamer. Black goop flies everywhere otherwise, and its really hard to clean up afterwards.

After reaming it out, I submerged my intake in grease-cutting soapwater for a week while I flew off to Boston to help my folks move. This proved to be a waste of time and soap, but I think it might have softened up some of the baked-on stuff. After multiple washes in a soap-water bucket, I went a different route. I had a gallon of diesel in a travel container, some carb cleaner from when I was trying to get the old air-cooled engine running and brake cleaner. Of the 3 which do you think was most effective? The BioDiesel.

First, I soaked it for a couple of days in pure carb cleaner. At one point I was afraid that it could damage the intake, but it just removed some of the gunk. Quick wash in soap-water, and I started spraying brake cleaner. That got the outside nice and clean, but had almost no effect on the remaining black residue inside. Then, I tried that container of diesel. I poured some in, swished it around, and poured it off - black. The inside of the intake, however, was getting shiny. I did this a couple more times and then washed it in soap-water again. There were a few little crud-balls that I worked out with a rag afterwards, but 90% of the intake inside was shiny under a light. I wonder how effective this would have been from the get go - just drop it in a gallon of BioDiesel and let it soak for a while. I still want to thread strips of rag through the intake and buff out any little bits, but I think its pretty much clean.

I have to re-direct my time again. This time, its to the old Mercedes wagon (w123) my wife drives. Its time for the valve adjustment, replacing the valve stem seals, a couple of vacuum actuators are bad, etc. So, since cleaning the intake, I've been diagnosing problems on the wagon, and have spent no more time on this. I'll be spending all of next weekend on that car, but then I should be able to refocus on the bus again. Last weekend, we went to Seaside and experienced their "Muscle Beach Weekend". I'll post on that later--