DIY LFX Intake Manifold / Valve Cleaning

[terry_b]

Well, my buddy just bought a new compressor. My plan was to enlist him and manually turn the motor over untill I can confirm the valves are closed and then erect a trash bag tent over the intake valves. I'd use a shop vac to get all the media out.

I'm kind of wary as well, but the brush seems like it may not clean quite as well. I don't know... Either way I'll post plenty of pics and such

[intensifi]

Originally Posted by ChadG

That scares me just because I don't see how you'd ensure you get all the media back out . . . plus if your valve isn't completely closed then you're also going to get some in the cylinder.

Make sure you close the valves when doing any cleaning on a given cylinder. The instructions discuss how to manually close the valves on a given cylinder.

[911medic]

I think one of the benefits of using the walnut shells for blasting is that any stray fibers/materials burn up if they make it into the cylinders.

BMW uses them to clean their intake valves, albeit with a special tool that blasts and extracts the debris simultaneously, IIRC.

[ChadG]

Originally Posted by 911medic

I think one of the benefits of using the walnut shells for blasting is that any stray fibers/materials burn up if they make it into the cylinders.

BMW uses them to clean their intake valves, albeit with a special tool that blasts and extracts the debris simultaneously, IIRC.

So the debris won't scary the pistons or cylinder walls?

Also how do you test that the valve is closed other than putting something like liquid seafoam in there to see if it puddles or not?

[911medic]

Originally Posted by ChadG

So the debris won't scary the pistons or cylinder walls?

Also how do you test that the valve is closed other than putting something like liquid seafoam in there to see if it puddles or not?

Well, I'm not a service tech or engineer, so I guess I can't say for sure, but I believe that's the idea behind the walnut shell blasting. Abrasive enough under pressure to clean, but the natural fibers/bits burn up/flow through if they get in the cylinders.

BMW's direct injection engines suffer from the same issues ours do, and their dealerships do walnut shell blasting with a special tool.

Here are a couple of links to BMW user forums where the blasting is discussed:

• First, a thread regarding manual cleaning of the valves (similar to the procedure outlined in this thread). There is some discussion of walnut shell blasting in posts #49, 62, and 137. One user mentions issues of the shells just sticking to the gooey build up, but there are some pics of some VERY clean valves after shell blasting in there, so it is effective.
• Second, a thread where a user bought the BMW blasting equipment. The end results are impressive--pristine valves.

I know Harbor Freight has some walnut shell blasting media equipment for pretty cheap, IIRC, but I don't know how good it is.

As far as checking for valve closure, I don't know of a better way than seeing if an engine-friendly liquid will pool on top of the valve. That's what I did when i cleaned my valves (see post #73).

[terry_b]

I may be making a trip up to harbor freight tomorrow. Wow! Those are some clean valves!

So I guess it would be easiest to remove the spark plugs to rotate the motor and shut each set of valves, and then just hook up the blaster and a vacuum and go to town right?

Is there anything special about removing spark plugs?

[ChadG]

Originally Posted by 911medic

Well, I'm not a service tech or engineer, so I guess I can't say for sure, but I believe that's the idea behind the walnut shell blasting. Abrasive enough under pressure to clean, but the natural fibers/bits burn up/flow through if they get in the cylinders.

BMW's direct injection engines suffer from the same issues ours do, and their dealerships do walnut shell blasting with a special tool.

Here are a couple of links to BMW user forums where the blasting is discussed:

• First, a thread regarding manual cleaning of the valves (similar to the procedure outlined in this thread). There is some discussion of walnut shell blasting in posts #49, 62, and 137. One user mentions issues of the shells just sticking to the gooey build up, but there are some pics of some VERY clean valves after shell blasting in there, so it is effective.
• Second, a thread where a user bought the BMW blasting equipment. The end results are impressive--pristine valves.

I know Harbor Freight has some walnut shell blasting media equipment for pretty cheap, IIRC, but I don't know how good it is.

As far as checking for valve closure, I don't know of a better way than seeing if an engine-friendly liquid will pool on top of the valve. That's what I did when i cleaned my valves (see post #73).

That makes sense, but now I'm worried that if you check that the valve is closed with something like Seafoam then the walnut shells will get all wet and stick to things?

Originally Posted by terry_b

I may be making a trip up to harbor freight tomorrow. Wow! Those are some clean valves!

So I guess it would be easiest to remove the spark plugs to rotate the motor and shut each set of valves, and then just hook up the blaster and a vacuum and go to town right?

Is there anything special about removing spark plugs?

I think the spark plugs are pretty straight forward, what you said should work fine.

[terry_b]

I'm actually thinking about doing the seafoam treatment AFTER I blast with the walnuts. That way I can just vacuum out the shells. I'm itching to dig in and see what the valves look like. Truthfully, I'll be a little disappointed if my valves are actually clean lol!

[911medic]

Originally Posted by terry_b

I may be making a trip up to harbor freight tomorrow. Wow! Those are some clean valves!

So I guess it would be easiest to remove the spark plugs to rotate the motor and shut each set of valves, and then just hook up the blaster and a vacuum and go to town right?

Is there anything special about removing spark plugs?

I was able to turn my crank bolt, slowly, without pulling plugs. But if you do pull them, just add a small dab of anti-seize to the threads before you replace them and torque them to spec and you should be fine.

[911medic]

Originally Posted by ChadG

That makes sense, but now I'm worried that if you check that the valve is closed with something like Seafoam then the walnut shells will get all wet and stick to things?

Yeah, I suppose that may happen. Not sure what to tell you.

[terry_b]

Well I picked up the blaster and the walnut media earlier today... ran into some complications... I think the reason the bimmer guys were having such good luck is that little tool that fits into the port. I either sprayed walnut shells everywhere or didn't get enough in one place to do any good... I may give it another shot tomorrow and see how I do... one problem is that I have some really carbonized valves. Way worse than I thought, and I was having trouble with the walnut media just sticking to everything in the port. It did seem oily still, an my intake manifold was a mess! I never cleaned it after installing the catch can, so there's a chance its just residual oil, but I don't know. More to come...

[ChadG]

Originally Posted by terry_b

Well I picked up the blaster and the walnut media earlier today... ran into some complications... I think the reason the bimmer guys were having such good luck is that little tool that fits into the port. I either sprayed walnut shells everywhere or didn't get enough in one place to do any good... I may give it another shot tomorrow and see how I do... one problem is that I have some really carbonized valves. Way worse than I thought, and I was having trouble with the walnut media just sticking to everything in the port. It did seem oily still, an my intake manifold was a mess! I never cleaned it after installing the catch can, so there's a chance its just residual oil, but I don't know. More to come...

That sucks, kind of what I was afraid of - good luck getting it squared away!

[911medic]

Originally Posted by terry_b

Well I picked up the blaster and the walnut media earlier today... ran into some complications... I think the reason the bimmer guys were having such good luck is that little tool that fits into the port. I either sprayed walnut shells everywhere or didn't get enough in one place to do any good... I may give it another shot tomorrow and see how I do... one problem is that I have some really carbonized valves. Way worse than I thought, and I was having trouble with the walnut media just sticking to everything in the port. It did seem oily still, an my intake manifold was a mess! I never cleaned it after installing the catch can, so there's a chance its just residual oil, but I don't know. More to come...

Too bad. Might have to try the manual cleaning method, which is much more labor intensive.

[intensifi]

Originally Posted by terry_b

one problem is that I have some really carbonized valves. Way worse than I thought, and I was having trouble with the walnut media just sticking to everything in the port. It did seem oily still, an my intake manifold was a mess! I never cleaned it after installing the catch can, so there's a chance its just residual oil, but I don't know. More to come...

I believe the walnut shell blast is a final treatment, not an initial one. I can see how the initial oil buildup in the air pathways/valves would be a magnet for the shells.

Sounds like an upper induction cleaning followed by a manual wipe of any remaining oil, then the shells would be a reasonable approach.

I'd like to see some "after" pics when you get a chance.