EDDIE SANDERS 310 kit

[matusdkw]

:grr:

esr 310 kit

what happend with this?

jetting 188 main 55 pilot 4th needle
pump gas dome 185 psi
new pwr radiator
new hose kit

no answer from esr really very dissapoint with ESR :mad:

[matusdkw]

another pic

[matusdkw]

another

[86 Quad R]

what octane pump gas were you running in it and how old was the fuel when you last run the engine?

it would appear that the detonation grimlin played a role in that damage.

[Honda 250r 001]

def seomething was wrong.

we need more info.

octane you were running?
piston-cylinder wall clearence?
Did you let it warm up?
Compression?
leakdown test come out ok?
ports beveled?
Squish?

[86 Quad R]

just noticed you are from argentina. i'm thinking it must be detonation issues as the octane ratings there are quite different than in the usa.

[headache]

you definetly need more octane or more jetting. But i'm guessing octane. I know 185psi usually is ok on 93 but what elevation are you at?

[YFZ_Racer42]

I had the same problem on my 07 YZ250 (stock) three motor in three races

As soon as I put 1/2 c12, 1/2 91 octane, it never happened after that

[FL-R]

Mine did the same exact thing Twice. 1st time it lasted 5 months, Then the 2nd one didnt last 2 rides, i put my old stock jug back on and no prob-.
i had the same setup but im running a 190 main and im in FL. Im bout to order a new piston and run race gas or a mix.

[mxduner]

Thats def. detonation issue. Where is the timing at? and the octane is what i would look at for sure

[machwon]

I feel like its dejavu here. Wasn't there similar discussion last month? I thought I mentioned about octane requirements and different rating systems outside the USA. yes, another not enough octane situation.

[hondamancbr03]

I disagree with it being all pre-detonation issues...With pre-detonation issues you usually see pitting all around the top of the piston and in the center as well.....Gray-ish spark plug from metal melting is another sign. That piston looks like a over heating issue at the exhaust area, the rest of the piston looks good on top. I know it had a new radiator but the piston looks like all the heat was at one location.

[matusdkw]

i'm at sea level
96 octane fuel
wall clearence 0,0045 inch told by esr

i agree whit hondamancbr03
for me is there is a problem with the cylinder and it's not cooling at the exhaust area.
the question is what should i do with the cylinder?

[86 Quad R]

one way to tell if there may have been an overheating issue is to have a look see underneath the pistom crown. generally, the oils will bake on in that area. got any pics of it?

i also noticed in the pics you posted that there is also a deformation starting to develope in another area of the piston

[86 Quad R]

tt

[C-LEIGH RACING]

0.0045" piston to cylinder clearance & you still stuck the piston.

If it didnt have as much clearance as it does, you might could get some acid & boil the aluminum off the sleeve, hone just a little & replace the piston & go.
But realy, just wonder how much of the melted piston found its way down into the bottom end & hiding in those main bearing only to come out later & destory another piston.
Dont let it slip by you that some of that melted piston went out into the pipe, stuck to the pipe walls & could find its way back into the cylinder.
Be sure the pipe is sealed up good where it connects to the cylinder, raw air can be drawn back in if its not sealed & destory a piston like that as well.

Before you put it back together, you need to know that none of that piston went down into the bottom end, even if you got to pull it apart to find out for sure.
Next, you got to correct why it happened in the first place.

You know it was high heat that melted the piston edge, be it from to low of an octain gas, leaking pipe connection or to high of an ignition timming setting or could be a combo of all those.
More than likely though, reading the piston the jetting should be ok because only the top edge has melted & not a full seize.
Lean it would have damaged the whole piston.

Do a squish test once you get it back together, measure that & see what it is & then you'll probably need to get the head dome cut to lower the compression.

My bets on the pump gas.
Just because you think you got prem 96 octain, do you know for sure when the tanker driver delivered it to the station that he dropped the right gas in the right tank hole ??.
I know it can happen, dropping the wrong product in the wrong hole because I drove a tanker for awhile.

Thats the gamble all of you have that are trying to run a high performance 2 stroke engine off of pump gas, you never know what you'll get in the next jug full.
Neil

[hondamancbr03]

I've seen my friends Banshee burn a piston two times in a row and on the same side, while the other side looked fine...The piston looked just like yours. It wasn't until the second piston that he borrowed my leak down test kit and found that he had a air leak on a cracked intake boot. Even thou it had been running lean enough to melt the edge of the piston at the exhaust side the crown still had the dark brown burn spot, which threw him off from thinking it was running lean.....With lean you usually see it all over the piston crown and plug. I run at 215psi so i run race gas, but even at 185psi i would at least run 50/50 to be safe.

In my opinion .045 is very safe on head clearence......I don't know yet what my Honda is at but both my banshee's run at .035 and run 50/50 with no problem, i know it's a different creature but just throwing itout there.

Do you have a picture of your spark plug?

[red88r]

I don't remember all the details but my brother's Lrd265 pv did the exact same thing as yours did after he installed a new pwr radiator. It ran very hot!!!! He was racing Red Bud and that is when it happened. Motor was so hot it even smoked his clutch. And it was not plugged with mud or anything like that. We had the quad really dialed in too. He put the stock radiator back in-no problems. Now it even has a Duncan 340pv with stock radiator. We still have the radiator cuz we did not want to sell it to somebody and have it ruin someone else's motor. He never did contact pwr or anything like that even though I would have. Just throwing in my 2 cents worth.

[machwon]

Originally posted by matusdkw
i'm at sea level
96 octane fuel
wall clearence 0,0045 inch told by esr

i agree whit hondamancbr03
for me is there is a problem with the cylinder and it's not cooling at the exhaust area.
the question is what should i do with the cylinder?

Matusdkw, how can we help you here? Many posts here including myself are telling you this is caused by detonation.

I find it hard to belive ESR doesn't tell their out of country friends about octane. On the other side, it's probably not a speciality of the parts counter guy. This year alone I've sent 2 motors to Belgium and 1 to the dominican republic. Both of these countries use Research octane Number (RON) to grade their fuels. I made both of these guys put in writing what octane rating system was used and what octane they were going to run before I set their cylinder head up. They both have had no issues what so ever.

The states use the average of RON and the Motor Octane Number (MON) to grade our fuel. both methods use the same engine but the MON test is more a more severe test. For example if your fuel does have a 96 RON, its MON rating is likely more like an 88. This would only be a 92 octane in the states here. This was the case for both Belgium and Dominican republic. I would look for some higher octane fuel to help solve your detonation issue.

[machwon]

The overheating issues can be complicated too. The pictures provided here tell a story, just like every piston tells a story. The cylinder it self is not disfunctional from a cooling stand point. The radiator was not boiling over was it? That would be a cooling system failure. In that event it would thermally expand the piston too much. The results would be a piston stuck on all sides of the bore, but with no pitting on the dome and no aluminum melted strictly on the exhaust side above the ring. This piston failure primarily had too much heat on the exhaust side, some on the top of the piston dome from pitting, some from piston expansion. Detonation causes excess heat (and other crazy things) which is what melted the piston. I need a typist, my fingers are cramped.

[hondamancbr03]

Some people have to talk until everyone agrees with them!

The piston did expand...Look at the pictures better, drag marks front and back of the cylinder. The gray matter on top of the piston is not pitting, it's the piston material melting to the top of the piston. There is no pitting under the plug or around the squish band as detonation does......I agree that he was running too low of octane, but that too causes the heat in the area that is subject to heat more than anywhere else on the cylinder...The exhaust. A melt down like that looks like low on water, not enough water flow, or just good old fashioned overheating.

matusdkw, hate to see a good engine go bad...I hope you can take all of these post and figure out what happened and avoid it in the future.

[Langbolt]

matusdkw, I've seen that kind of destruction from a coolant leak at the head gasket.....but you're running o-rings. How do they look ? Is there a tear or was the inner one pinched in the groove ? I'm just throwing out some more areas to check. I know you have to stretch the O-rings a bit before you install them so they fit in the groove perfectly. I'm wondering also if the fuel may have been contaminated ? How clean is the fuel down there ? Or are you using fuel from a supplier like VP or are you getting it at the local gas station ?

Also,

What OIL are you using and at what ratio ? 32:1 ???

:(

[fulltiltrider]

Its definately a deto issue or a lean condition. Not from overheating. It takes 1200+ degrees to melt a piston like that. A bore temp of 240 is high enough to stick a tight piston. It for sure would never make it past 300 without seizing. Not high enough temps to cause this. Now antifreeze leaking into a combustion chamber can do this fast. Next time when you put it together run straight water till you figure out the issue. If it is a leaking issue the water wont cause deto. My guess is with machwon, its a octane issue.

[destey]

newbie guess here, but cold seizure? I've seen a lot of people kick it and rip it :ermm:

[C-LEIGH RACING]

Cold seize, will normaly be all way round the piston on the sides or just in 4 spots because the cylinder is still cold.

When you think about it, its crazy why it happens but thats how forged metels respond when you add heat to them real fast.
Neil

[destey]

Originally posted by C-LEIGH RACING
Cold seize, will normaly be all way round the piston on the sides or just in 4 spots because the cylinder is still cold.

When you think about it, its crazy why it happens but thats how forged metels respond when you add heat to them real fast.
Neil

I always figured it was a mass issue, cylinder + coolant would take a lot more BTUs to bring all the cylinder molecules to operating temp than the smaller mass of the piston.

I've heard the forged pistons expand faster than cast. Is it because the molecules being closer together must push themselves away from each other quicker than if they were further away?

[C-LEIGH RACING]

Originally posted by destey
I always figured it was a mass issue, cylinder + coolant would take a lot more BTUs to bring all the cylinder molecules to operating temp than the smaller mass of the piston.

I've heard the forged pistons expand faster than cast. Is it because the molecules being closer together must push themselves away from each other quicker than if they were further away?


Hummm, I guess they are pushing away, causing the piston to expand faster & taking up piston to cylinder clearance.

If you see somebody start up a 2 stroke bike engine & just blast off before warming it up, without a dought that engine has a bunch of piston to cylinder clearance to keep that piston from sticking, or either it has a cast piston inside thats a little more forgiving.
It can happen with a cast piston as well, all about piston to cylinder clearance though.
Neil

[machwon]

Originally posted by destey
I always figured it was a mass issue, cylinder + coolant would take a lot more BTUs to bring all the cylinder molecules to operating temp than the smaller mass of the piston.


I like this thought and yes the cylinder + coolant are usually thought to be a more constant temperature. This is the advantage of liquid cooled and ...rather that type too much. How about the detonation causes the piston to melt. The melting eventually erodes the piston and sticks the ring(s) in the groove. Now I have hot combustion gases getting beyond the ring, Oh NO! The lubrication is burned away and melts the piston to the wall.

[destey]

Originally posted by machwon
How about the detonation causes the piston to melt. The melting eventually erodes the piston and sticks the ring(s) in the groove. Now I have hot combustion gases getting beyond the ring, Oh NO! The lubrication is burned away and melts the piston to the wall.

Delving more into the detonation melting the piston... What causes the aluminum to melt thus sticking the rings?

If I understand motors correctly MBT is the maximum spark advance without detonation. To advance spark more, either octane has to be increased (which decreases tendency to burn) or cylinder pressure has to be decreased (ie engine load).

So a motor with detonation has too much spark advance, too little octane, or too much compression; would that be correct to say?

That would be the why detonation happens, but why does it cause hotter piston temps? Is it because in a normal 14.7:1 stoich engine stroke there's a little gas left unburnt after firing that gets burned up as cooling, and that doesn't happen during detonation?