how to clean exhaust ports

I pulled my exhaust headers tonight to replace a cracked exhaust nut and clean them up. Once I peeked in the exhaust port (where the exhaust valve sits), I saw tons of build up. I guess it looks like carbon? Anyways, is there a way to safely scrap/clean that without having chucks fall down into the engine?

Also, how to you get the exhaust nut washer off to replace? thanks

 

the only way to keep anything out is to be sure the valve is seated against the head and use a powerful vacuum.

I wouldn't recommend doing that though. the only best way to do it is pull the head and have it professionally ported and polished.

 

When you say "tons of build up", are you really talking about maybe some pancaking of carbon but it's not really thick enough to cause a measurable loss in port diameter? If that's the case, there isn't much point in cleaning it since it return rather quickly. I'd stick with tier 1 gasolines for a couple of months and see if the problem resolves itself.

Crap gasolines are exactly that but most people will pour it in their engines to save a dollar or two then waste the dollar they saved by buying toilet paper at the grocery store. Yeah, odd.....but so true.

We've all known people who go through 3 redlights to save a penny on gas yet their car is one of ther most important assets. I used exxon for a year, only exxon for one of my bikes that was bought brand new. Ended up just like yours, probably even worse. I couldn't believe how much crap was in the intake and exhaust. I switched to Shell and Sunnoco and the build up disappeared inside of 3 months.

Fairly easy to clean the passage at the opening to the pipe but be absolutely sure the exhaust valve and intake valves are both open, at the overlap point. If you don't, your vacuum will not create any flow. Then use a brass fitting brush and a good strong vacuum. You can also wad a small piece of cotton cloth up real tight, insert it without touching the walls as far into the port as you can. When you release it, it will expand and prevent and debris from entering the valve seat as you clean and when you pull it out, it will bring the trash with it. I doubt it will result in any noticeable difference though.....jmho

Not really sure what you mean by a stuck "nut washer" but if a washer won't budge, chase it in a circle with a small, flat blade and rubber mallet. That type of adhesion usually isn't that strong a bond and by chasing it in a circle, you'll be applying sheer against that bond and most things will break loose.

jeff

 

Shop vac, small stiff nylon brush (old toothbrush) and don't worry a whole lot about it.

And it you mean how do you get the exhaust collar off, you have to remove the pipe, remove the little EGA port plug on the bottom and it will slide right off.

Be sure to use new exhaust header-to-head gaskets, and depending on what condition it's in, you might want to replace the collector seal on whichever pipe you pulled.

 

are you sure what your seeing is carbon build up or is it the part of the head that houses the valve guide that always looks like a pile of carbon. if your 100 percent sure the valve is seated use a dremel with a flex tip with a brass brush suck it out with a vac.

 

It's more just some crusty pancaking. I think I'll just stick the shop vac in there and clean out the flakes and be done with it.

BigFtiz, I'm talking about the exhaust header-to-head gaskets. They seem to be pressed in pretty good. Wasn't sure if there was a good way to get it out.

Also, pulling the headers, I snapped the small 10mm nut at the bottom bend of the header. How critical are those?

 

I will humbly disagree. You want to be sure that the exhaust valve is closed. Remember your last trip to the dentist? You know, getting your teeth cleaned? Recall that when you had the suction tube in your maw, the suction would only suck up what was immediately near the inlet port. But, as soon as you closed your lips around the tube, EVERYTHING in your mouth got sucked out! In the case of the port, if the vacuum doesn't have a hose big enough to encircle/seal against the head, use a rag wrapped around the nozzle.
You can clean each port as the fellows are indicating but be sure that the valve for each is closed so as to prevent any loose wires from dropping into the cylinder. I'd recommend a biocarbonate of soda blasting... The left-overs can be washed away with any solvent (or water) and any residue will be blown out by the exhaust pressure.

 

This may be a dumb question - but how am I POSITIVE that the valves are closed?

Also, won't some valves be open while others are closed or am I thinking about that wrong?

 

Your are thinking wrong. The valves all HAVE to ALL BE CLOSED for it too have a compression stroke, and to have a COMBUSTION stoke,or it will NOT RUN! You can hook air to the Spark-Plug with a hose from a compression gauge,it let you know if all the valves are closing. If the exhaust valve is not closing you will hear air out the exhaust,if intake is not closing you will hear air leaking back to carbs. I sometime run Trick Racing Fuel a few times,runs great,& cleans any carbon build up in a hurry.

 

I appreciate you taking the effort not to sound like a "know it all" and hope that I also do not come across that way. I disagree with your analogy though since the engine is in a static condition and ports won't be "sucked in" as the negitive pressure increases, it would more akin to trying to suck a spitball placed halfway down a metal tube with the other end capped but it doesn't matter,

If the guy can get whatever he's facing, resolved. Then that's the only thing that matters, not whose correct. That's the great thing about advice, it's free and the listener can take it or leave it.....

PS. I haven't opened one of these engines (yet) but in most 4 strokes you just rotate the engine and watch through the exh port to see the valve stem(s), when they lower the valve is opening and when it rises it's closing.

jeff

 

The best way to get the pressed-in gaskets out is to dig a pick into them, as soon as they distort even slightly they'll pop right out. Just be careful not to gouge up the head.

That little 10mm bolt is the EGA port I was referring to; as long as the remnant of the bolt is still firmly lodged in the threads don't sweat it. The only concern would be if the stub falls out and creates a leak.

And yes, you can see enough of the valve stem through the port to tell when it opens/closes.

 

Unless you have an XJ1100. In which case those collars ain't coming off, at all, unless you break the spot weld on the lower tube(s), where the tube enters the "collector".

Nice bit of factory engineering, that............ 8O