manual valve cleaning (1 Viewer)

[AaKnight]

So I had a VERY dirty TB and removed it to clean it, at that time I was surprised how dirty the intake plenum was so I removed the upper and cleaned it.... I'm now considering my options for the lower intake, and valves. they have to be filthy as well.

I am thinking about removing the lower intake now to clean out the ports and valves, which I assume are as nasty as the rest of the intake.

Question is: is this a good practice for this engine? or am I opening up a can of worms here?

Anyone have any advice for cleaning the lower intake and intake valves?
You think i would see any benefit from doing this versus a BG or seafoam/b12 type intake treatment?

Thoughts?

 

[Timpanogos Slim]

Since these engines are port injected, I'd be surprised if there is substantial carbon buildup on the intake valves. Atomized fuel should be routinely washing them clean - certainly if you perform the occasional italian tuneup.

If you get in there and they are very dirty, the manual method is to rotate the engine by hand until the valve you want to clean is closed, stuff rags in the other valves, and use rifle cleaning brushes and the solvent of your choice (say, berryman chem-tool), and shop rags to mop up spent solvent.

The less manual method is to use a walnut or baking soda blaster.

I've spent some time studying this because i have a direct injected car that probably has very dirty valves at 106,000 miles.

another option is to periodically, immediately before an oil change, use an inline fuel pump and a misting nozzle to spray a pint of mineral spirits mixed with a pint of fuel injector cleaner into a vacuum port in brief pulses while the engine - at normal operating temperature after a good drive - runs at 2000rpm or so. Maybe more than a quart on a big ol tractor motor like ours.

Which is what i'm planning to do on my carboned-up DI engine.

To keep it clean in the future you should look into a catch can for the PCV system.

 

[AaKnight]

Thanks for the info. ,,, do you think that at 140k miles it would be beneficial to go to that much effort? or would a "reasonable" person stop and call it good? at what point is that level of cleaning service really needed?

 

[Timpanogos Slim]

Well, here's what i'd call egregious carbon buildup - in a volkswagen tdi intake manifold:

And I've seen worse. This is actually sorta common. There's a 300,000 mile '99 TDI Jetta in my driveway that i need to yank the engine and transmission out of before winter so i can get rid of it's carcass, and i fully expect to find something similar.

That's a major restriction - due to both PCV vapors and EGR.

I'd say if it's crusty, clean it. If it's just dirty - meh. I guess if the truck is down anyway you may as well clean it?

EGR failure with major carbon buildup isn't uncommon on our engines. Some people have resorted to drilling out the EGR channels on the throttle body. The manifold can be baked out by a decent machine shop (just like a self-cleaning oven) - it may be there a few days to a week or so before it's done but it beats arguing with it for hours with solvents and elbow grease.

I still think that when you get the bottom half of the intake manifold off you'll find relatively clean valves.

 

[AaKnight]

Funny you mention that, my DD is a B6 Passat from 2006 with 240k, I'm about to pull the motor to do the timing chain as my cams are max adjusted..... wait this isn't vwvortex, wrong forum

As for my 80, it's just dirty and gritty, about 1mm of gritty carbon buildup on the walls. upper part of the intake was just soaked in chemtool and I had to work at the egr ports. I'm just debating if there would be any real benefit to justify the time and expense of doing it. I'm probably gonna just do the upper for now.

 

[Timpanogos Slim]

Yeah there's a weird overlap between VW/Audi ownership and Toyota 4wd ownership. In the dead of winter the european car club i hang out with starts sporting a lot of cruisers and 4runners.