out in ecj pilot started loosing power then shut down. After thinking it was just something simple, Hare pull on the pull start and didn't even break a sweat. NO COMPRESSION.

Here is what I found.

and more

is it possible that the missing part of the ring has just shaved down to nothing and disappeared?

The bottom end of the motor (( Internal Combustion Engine ? )) seems nice and tight and moves smoothly with no signs of particals.

Jug also looks in good shape to me....maybe a hone. With a new piston and rings and seal kit, I could be off to the races in no time.

What you guys think?

WOW!

Locate that missing part of the ring, you can put a small CLEAN towel by the rod then SLOWLY rotate the crank around and the rag will follow sweeping as it goes then once you do about a 360 you can carefully remove the rag to see whats on it.

What pipe and silencer are you running?

Sow me pictures of the exhaust manifold inside and out and also the pipe inside and out where it connects to the cylinder.

Shake the pipe is the missing ring inside the pipe silencer?

picks of exhaust manifold and also some parts I found after you ask me to shake out the silencer.

I'm using a torque pipe an silencer from Marv

more

I see some things I don't like, go here and read this viewtopic.php?f=109&t=13671

I need you to remove the exhaust manifold and stick it in the pipe and take some pics so I can see how it matches the pipe...

What kind of oil are you using and at what ratio?

I don't like the size of the buildup in the exhaust manifold where the blue arrow is did that piece get sucked back into the Engine?
look how far the piece sticks out where the pink arrow is and were the green is pointing is that missing or was never their?

The size of that piece is scary!

Try to preserve it if it falls off send it with the parts please.... it evidence... I want to run it through the hoser labs

When I say sucked back in watch this animation when the fresh fuel and air is sucked out into the head pipe then the return pulse wave <<<<<< pushes the mixture back into the cylinder before the piston covers the exhaust port...

Some of those pcs may be what is stuck to the head. You can do your analysis when you get it.....I will send you the pipe and silencer too.

I use Castor927 and mix is 40:1

That is very similar to what happened to mine. Your top ring ends have migrated around to the exhaust port and nipped up. Where as on mine it was the bottom ring. Can you still see the top ring locater pin?

Silly question... Would replacing the rings BEFORE this happens is it possible to just pop the top and put new rings on exsisting piston? or do you need to replace the piston and renbore, or hone...

yes top locater pin still in place

Hi
Got your package, power has been out so haven't got much done but I am working on it today, the head is almost cleaned up and ready to go, initial look at the cylinder shows HUGE amounts of wear on the piston HUGE amounts of carbon build up in the exhaust, HUGE amounts of tar muck buildup on the underside of the piston, all abnormal.

I don't know anything about Castor927 anybody else running this oil?

Secure any empty bottles of this oil and any that you have not used yet....

Any signs of a coolant leak, once you reinstalled the Engine I assume you topped off the coolant then never had to add any?

Any black specks of pepper in the old coolant or in the coolant rez?

Any oil in the coolant system ?

Here are some more pics I took the wet look is from the antifreeze other wise it would be dry looking.

Stuff I scraped out the inisde of the exhaust manifold..

You can see the carbon buildup behind where the ring was.

Bottom side of the piston, I scraped it with a screwdriver.

How many hrs on this since the rebuild?

Where does the carbon build up form from?
Is it poosible to be the oil?
Is the cause of this the breakoff of the carbon getting sucked into the cylinder?

Coolant never needed to be filled after topped off from the first time after the rebuild.

Check coolant - it is free of oil and black peeper - looks clean.....

hours on Engine are between 25-30

Some info I found on oils.

THE RELIABILITY of any Engine is closely related to adequate lubrication and efficient cooling. Unfortunately, it is in these areas that the two-stroke Engine is most vulnerable. It has to rely on just the scantiest supply of lubricating oil to resist piston seizure in a cylinder badly distorted by the steep temperature gradient existing between the hot exhaust side and the much cooler inlet side of the barrel.

The lubricating oil must be able to prevent metal to metal contact of moving
Engine parts and at the same time assist in conducting heat away from the piston crown
to the cylinder wall. Additionally, it must form a seal between the piston rings and cylinder wall to contain the pressure of combustion effectively. If the oil film is too thin, blow-by will result, reducing the amount of energy available to power the piston down.

There are basically three types of oil: mineral oil derived from crude stock; vegetable oil from the castor bean plant; and synthetic oil, which is man-made or man modified and used straight or blended with mineral or vegetable oil.
Most motorcycle oils are mineral-based, with a variety of additives used to improve them in certain functions. I would recommend mineral oils for all except competition two-stroke engines. My favourite mineral oil is Castrol Super TT. It will provide very good lubrication and wear resistance, better I believe than any other mineral oil available and better than most synthetic and castor oils. Like all mineral oils, Super TT will dirty the plug, and leave some carbon on the piston crown and in the combustion chamber.

In all of my competition engines, I specify Castrol R40 or R30 castor oil (R40 for air-cooled engines, R30 for water-cooled). This oil provicfes the best anti-wear protection of any oil that I know. The mere fact that my engines produce top horsepower testifies that it must be doing an excellent job of reducing friction by keeping moving parts separated. When you strip a 12,OOOrpm road racing motor (( Internal Combustion Engine ? )) after 300 racing miles and find the ring gaps opened up by only O.007inch, and hone marks
) still visible on the cylinder walls, then you know the oil you are using is good.

Many tuners do not like castor oil or blended castor/synthetic because of some problems associated with the use of an oil of this type. Some claim that castor gums up the rings and causes ring sticking, but I have never found this problem, even on engines that are required to run 500 miles between rebuilds.
There is one area for concern, and this is the main reason why oil companies try to discourage the use of castor oil. Castor-based oils are hygroscopic, which means they will absorb moisture from the atmosphere. Therefore, once a container is opened, its entire contents should be used, or if oil is left over this should be poured into a smaller container so that no air space is left above the oil from which to absorb moisture. Remember, too, that castor oil will also absorb moisture after it has been mixed with fuel. Therefore, do not use fuel more than three days old, and don't forget to drain the fuel from the tank and carburettor bowl.

While we are on the subject of castor bean oil, don't think for a minute that all castor oils are as wear resistant as Castrol R. This all depends on how well the manufacturer de-gums the basic castor stock and on what additives are used. Some castors provide wear protection no better than average mineral and synthetic oils.

Today, more and more people are turning to and advocating the use of synthetic lubricant. There are several points in favour of synthetics, namely: less exhaust smoke, less incidence of plug fouling and less build-up on the piston crown and in the combustion chamber. Some also claim better wear protection and more power as a plus in favour of synthetic lubes, but in general my research has produced an opposite result. I have found some synthetic oils to have a wear factor twice as high as the better castor and mineral oils and I have never found a synthetic to allow an Engine to produce as much power as Castrol R. For these reasons, I could not recommend the use of synthetic oil in highly stressed competition engines.

The manufacturers of synthetic oils claim their oils will give better power because the amount of oil in the fuel can be reduced (eg: Bel-Ray MC-I is mixed 50:1 as compared to 20: I for most mineral oils). But why should it ever be imagined that a smaller quantity of lubricant entering the Engine will give a power increase? At the' races it almost seems as if there is as much glory to be gained from running a fuel/oil ratio of 60: 1 as there is in actually winning the race; by the pit bragging going on it would seem to be so!

My experience has shown that the more oil you pour into a two-stroke, the harder it runs. Just how much you should pour in depends on several factors, but it usually works out that the longer you hold the throttle wide open, the more oil you should use. This is due to the fact that the fuel/air ratio will be leaner at full throttle than at half and three-quarter. Therefore, with less fuel entering the Engine at full throttle, proportionally less oil will be available for lubricating the piston at a time when it requires the most lubrication. Spelled out, it means that on a track with long straights you will have to use more oil than on a tight twisty track.

Keep in mind that your Engine only needs enough oil to lubricate one stroke at a time and then the excess is burnt up. If your bike is oribbling oil out of the exhaust then you are running too much oil for its needs, or for your riding speed. A faster rider on the same machine may need more oil, because he is holding full throttle for longer periods.
When you start experimenting with oil ratios, always use the Engine manufacturer's recommendation as a reference point and work from there. If you go too rich, the spark plug will be coated with black soot and the exhaust pipe will be wet. If there is not enough oil, the plug could look white or grey, the pipe will be very dry, the piston crown will be white or light grey, possibly with 'death ash' forming under the crown. Any of these signs indicate that you are bordering on a seize up.

Generally, I would say that road racing engines will work best at a 16: I to 20: I fuel/oil ratio, depending on the nature of the course. Desert racers require 16: I but, if plug fouling proves to be a problem, try 18:1 or 20:1. For enduro and motocross 20:1 or 22: I is the best ratio. Go-karts with fixed gearing, without a clutch operating on short sprint tracks, will usually not tolerate more oil than 25: 1 and, if you find that you are fouling plugs, you may have to drop as low as 30: 1. Under no circumstances should you run leaner than 32: 1.

All of the above fuel/oil ratios are for mineral and castor oils. Synthetic oils are an entirely different kettle of fish. If you choose to use this type of oil you will have to run it at the ratio the oil manufacturer recommends. This is because the oil people load the oil up with additives, in an attempt to give it acceptable scuff resistance when mixed at 50: 1. Mixed at 25: 1 there will be twice as much chemical additive and detergent being inducted into your Engine and this could very easily cause carbon build-up and plug sooting, serious enough to stop or even damage the Engine.
It seems that the trend towards leaner and leaner oil ratios has resulted from the desire of two-stroke Engine manufacturers to eliminate plug fouling completely in two- stroke mower, outboard and chain saw engines. These engines are seldom serviced and the plug is probably only changed each time the rings are replaced. To cut down on spark plug deposits, the manufacturers decided on less oil and, unfortunately, this idea has carried over into competition two-stroke circles.

The results of my most recent oil testing are shown in TABLE 8.1. The Engine was a fully worked Suzuki RM 125C motocross unit. As you can see, reducing the oil content from 20:1 to 27:1 (I wasn't brave enough to lower it any further) resulted in a power loss of about 8"10 at the top of the power range - a heavy price for the sake of a clean plug. On top of that the piston showed signs of scuffing bad enough to deter me from testing at 32: 1 which, according to a lot of tuners, is the best mix when using R40.

When the fuel/oil mix ratio was raised to 16: 1, power was marginally improved by about 2"10, which is almost too small to measure on the dyno. However, the piston was much cleaner and the rings showed no sign of gumming up.
Accuracy is of utmost importance when blending oil and fuel. It is of no use mixing one and a half beer cans of oil to each drum of fuel, you have to be precise. For measuring the oil you need either a laboratory measuring cylinder or a graduated beaker. Fill the measuring container with the required quantity of oil, and be sure to allow the oil plenty of time to drain out when you pour it into your drum of fuel. Keep the measuring equipment clean, preferably in a dustproof plastic bag.

I wonder if hygroscopic is your problem?

Looks spooged from hell, excessive idleing maybe? damaged reed? bean oil?

Castor 927 often refered to as bean oil, which i thought was a non syn oil, its a natural bean for christ sake. Back in the day they were known for gumming up the works with power valves and such. They used to smoke like crazy, had that smell from a mile away.


Some Maxima guy said

"927 is a blend of ester synthetics and castor oil (vegetable oil.) The blend and components are proprietary, but I can tell you that there is more castor oil than synthetic and that both base oils are in at significant amounts. Castor oil itself is very similar to ester synthetics and are looked upon as naturally occurring synthetics."


I like this one, from some internet mutt

"In summary, it’s fair to say synthetic based oils (with the correct additive package) will out perform their petroleum-based cousins at extreme loads/temperatures. I mentioned a third category of base oils earlier, vegetable or Castor (not Castrol, that’s a manufacturer) bean oil. This oil is derived from pressing oil out of castor beans and distilling it. ‘Bean Oil’ as it is often referred to, has some very unique characteristics; some very good, others not so good. The good is that it is an excellent lubricant. It seeks out hot spots in the Engine and clings to those hot surfaces much better than petroleum type oils. The bad is that it does not mix with gasoline easily and it burns ‘dirty’ (excessive carbon/varnish deposits). In the early 70s, before power valves were used, castor bean oil was very popular in racing 2-strokes. Now that power valves are common and we have improved petroleum and synthetic oils, castor bean oil is seldom used anymore. Several companies still market it in the form of a degummed castor oil for racing applications only. It should be avoided for recreational use unless you enjoy tearing your Engine down for a top end cleanup fairly often. Several manufacturers formulate their oil with castor bean oil as an additive (antiwear agent) rather than base oil. They blend it with their petroleum and synthetic base oils. When castor bean oil burns, it has an unmistakable ‘sweet’ smell."

I ran the maxima 927 castor oil for years and years and never had a problem with sticking power valves, rings, or premature top end failures. Sure smelled good though.