Pandora's Box?? Question on Carbon Buildup

[BroHay]

OK, so as most of you know, I'm back trying to finish all of the outstanding items that I've either obtained since ownership, or just tweaking to make the FZ the way I want it....

The one mystery that still has yet to be cracked is understanding all the nuances of the combustion engine. I'm a hands on kind of person, and reading a book does not always have the best results.

I purchased the bike with 25,222 miles on it and have since put approx 10k. When I removed the factory header, I was greeted with the following.....

Exhaust far left

Inside Left

Inside right

far right

Black deposits around the exhaust ports with little bits of grey knobs (like welding splatter) on top. If I look into the port, the shaft of an exhaust valve has a heavy build up but up close to the exit point, it appears to be relatively clean with minimal build up.

I'm going to get some better lighting and camera, and see if I cannot show what it is that I'm trying to describe in a better way.

I've never torn apart an engine, and frankly, until the bike, never really did anything. It seems overwhelming with searches on the "rehto" forum but the responses seem to be towards those with a basic understanding of the principles of combustion/compression/etc.

So, asking those with the knowledge, to help me understand what it is that I'm seeing and if it is minimal to cure or with a few extra steps, can continue down the road of blissful FZ ownership.

--I'll be doing the plugs/fuel filter/radiator flush and greasing all of the bearings/axles/etc., but will I be going further?

Adam

 

[Jeffibus]

Looks fine to me.

Remember this is not a skillet for cooking eggs, this is the exhaust port of an internal combustion engine.

Over time there is a slow build up of coke deposits on surfaces that do not have moving parts assisting in keeping them clean.

Taking an engine apart is a very bad decision, due to the number of gaskets, seals, plugs, rings, you would have to buy to put it back together.

Generally speaking, it would cost ~$300-500 to buy all the gaskets and seals to put everything back, assuming you didn't accidentally strip a nut or bolt in the process.

 

[BroHay]

then, is there somthing that can be done to eliminate the deposits w/o having to go through the laborious process of breaking down the engine?

I'm going to carefully clean around the ports to remove the buildup that is seen (shop vac with a various assortment of brushes) and try to not re-introduce that which I'm removing.

I'm not looking for a reason to tear into the engine, unless I absolutely have to.

 

[FZ1inTX]

One of the best things you can do Adam is to put Sea Foam in the first tank, get the engine up to temperature, then get the bike into the upper RPM range. Any place close by where you can run her out in 1st, 2nd and maybe 3rd? I'm talking all the way to red line. As we say up here, WOT and clear the crap!

 

[k27]

These deposits are normal for a stock Gen 1 engine due to lean AFR and hotter exhaust side.
Get a jet kit and the "problem" is solved within 1-2000 miles.
Do not disassemble the engine, there is nothing wrong with it.

 

[Lonerider59]

Hey Adam, that doesn't look bad for the miles you have on the bike. As I remember, you have an aftermarket can on your bike. Do you have any idea if t's been rejetted? The most you might want to do is to get it on a dyno and see what the A/F looks like. That can tell you a lot about how well the fueling is tuned in.

 

[BroHay]

it sits unjetted, for the momment. It is on my very short to do list.

I'll have to go pull the dyno and see what the A/F mixture was this time last year.