TRX250R.ORG
Workshop => Engine and Bottom End => Topic started by: patman13mia on June 23, 2014, 02:11:35 PM
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heres some pics of my topend from this past weeknd. i didnt even put an hour on it do to alot of individual issues. but one main issue was coolant leak thru the head bolts. i dont know if the oring was sealed correctly cause after 10 mins of riding i had to re toghten the head studs. maybe the oring slipped out of its groove then i tightened it down. also does it seem like the clearence from piston to cylimder wall is larger on the intake side than exhaust or am i just seeing things? i also had some black stringy things floatin around in the coolant passages. looks as if its from the orings. this is my first oring head. tony said there is some sealent or lube to put on these. what are you guys using? i have some more pics coming with the cylinder off so we can see whats goin on down there too. hope yall can help
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here are some more photos of the piston and bottom end spacer that i filed by hand. i went a lil to far and the divet into the cases is showing. does that make any difference in performance or hurt anything? i am waiting on the correct size gaskets and spacer to get here hopefully by this weekend. also my piston seems to have some cracks in it. it did have an air leak pretty bad at the end of the day which i think is from the unseated oring. the cracks are at the exhaust and intake sides.. what do you guys think? theres also a pic of the head as soon as i took it off.. does that look ok? there is coolant in there for sure
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I put a liberal amount of white lithium grease om the o-rings before installation and haven't had any leaks on my sphynx or PC2000
That piston looks like it has some type of crack/dent above the top ring, on both sides
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What do the o-rings themselves look like? Are they cut up at all? I suspect that is what is on your finger in the first post.
Is the top of the piston just scratched from ring installation? Clean everything up and take more pictures with it clean.
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What clearance do you have piston to cylinder? That piston looks cracked in several places. Looks like the compression o-ring was sealing from that one pic? Cant see any blowout area at least.
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ok when i get home i can take pics of everything cleaned up. as for clearance im not to sure. neil did all the work on it. i can find out though. the only way coolant could leak through would be cause of the orings correct?
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Other than a cracked sleeve I dunno where else it'd come from? Unless your deck surface isn't flat or sleeve is lower and the dome never really seated well.
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oh i never actually got a kick out of it without the spacer. it was caught up with the top ribg. i homestly think my problem was the head wasnt torqued down right and then when i went to torque it down the oring may have popped out. thats just my guess though
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It kind of looks like the water o-ring was sheared when you put it back together. The o-rings usually last a year or two before needing replacement. The cracks in the piston are unusual.
Coolant leaks through the head bolts happens cause there is no seal on any cylinder between the 2 o-rings. Your acorn head nuts will seal at about 20 ft-lbs
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It looks like you have a dome for a 330. It looks like the piston is hitting the head. I can see a witness mark about 1 to 2 mm wide around the circumference of the piston and head dome where contact is being made.
An 0-ring head should not need to be re-torqued. If the head nuts were loose it is probably due to the piston tickling the head. A piston that is tickling the head will also overload, collapse and break the skirts.
Detonation will often occur when the piston is close enough to make contact with the head. Detonation will also erode the inner edge of the o-ring. If the detonation continues long enough it will eat all the way through the o-ring.
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It looks like you have a dome for a 330. It looks like the piston is hitting the head. I can see a witness mark about 1 to 2 mm wide around the circumference of the piston and head dome where contact is being made.
An 0-ring head should not need to be re-torqued. If the head nuts were loose it is probably due to the piston tickling the head. A piston that is tickling the head will also collapse and break the skirts.
Detonation will often occur when the piston is close enough to make contact with the head. Detonation will also erode the inner edge of the o-ring.
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It looks like you have a dome for a 330. It looks like the piston is hitting the head. I can see a witness mark about 1 to 2 mm wide around the circumference of the piston and head dome where contact is being made.
Good eye Jerry. If the piston does not fit into the groove cut into the dome you will be able to tell by putting the two together. If it is hitting like Jerry says then you will want the correct dome.
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i dont know how to upload a video but i put everything together and paid more attention to what i was doing when installing. it doesnt leak out of the top of the head at all. i also performed a leak down test before installing pipe and carb and it was good. now when it runs it is making a loud noise as if it is hitting the head just like jerry said..how do i tell if i have the correct dome? i took the dome out to clean it and it is scribed 350 race dome.. it looks to have the diameter of the piston.. what should i do to fix this issue? maybe beed a thicker spacer plate?? please help!!
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Hopefully its the spacer plate. If its apart check the rod bearing also.
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If you were to have everything disassembled you just put the dome on the piston to see that the piston does in fact fit inside the small step that is machined into the dome. If it fits then you may need thicker base gaskets! Myself just use a calipers and measure the piston and compare to the step cut into the dome. There should be some clearance.
Did you use the 3mm or 5mm spacer?
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pretty sure i used a 3mm spacer and the two gaskets I used were .020 and .030
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Do a squish test with .062 solder and see what shows up. I'm with checking bearings also! Scary deal.
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yepp sure will do a squish test tomorrow after work. ill post some pics and show the results. thanks for all yalls help!!
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The 3mm is the thinner one, the 5mm or .187' is the thicker one which is the standard for the difference in the short to long rod conversion. If you were using the thin one then it might be hitting.
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ahh i gotcha. then yea i need to try the 5mm one. should i use the same size gaskets as im using already? do you happen to have a 5mm spacer i can purchase? i sent ya a pm on it already.
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The spacer you were using with the other cylinder is the thickness you need. I have some BB spacers you can have for no charge or the ones I cut i have to check stock. Either way I have what you need. :jumping0041:
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thank god for you tony!! lol..
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just throwing my 2cents in... if the squish clearance is off by as much as 1mm, the porting can't be very precise. Do you have a builder who helped you set up the engine? You might consider one if you're in the market to have your engine designed.
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yea understandable. i actually just got the engine back from neil at c leigh racing. he did all the porting n polish.. ive sent him an email and waiting to hear back from him now.. will post up what he says.
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ok when i get home i can take pics of everything cleaned up. as for clearance im not to sure. neil did all the work on it. i can find out though. the only way coolant could leak through would be cause of the orings correct?
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Ok, I'm here now, been away at a race so didnt know about this.
Just to clear up things so we all will be on the proper page, in this reply where it states "neil did all the work to it" ( no), all Neil did was port & bore & fit a brand new ESR cylinder. Just a typo I'm sure, but it could be looked at wrong by some & thats not me.
Now when I had the cylinder in hand for my work, I had no idea there was no spacer plate shipped with the cylinder kit like normal, but when the porting was being done to it, the ports were degreed in with the proper thickness of spacer plate needed to be used for that cylinder kit, so that the piston edge came up flush with the top edge of the sleeve.
As far as the head dome not being the proper size for the bore, it was measured & was the proper size for the 350 piston, even large enough for a couple size over bores when needed. Piston to bore was set up at 0.0030 like always for a Wiseco piston.
Now if this engine was running out of my trailer & I knew the rider, how they break an engine in, I might would set the clearance up tighter because I would have an eye on every step taken.
I know some ESR cylinders are set up with more piston to bore clearance, but when one leaves me it will be 0.0030 regardless of all the talk.
Ok, now after the PM I just got & answered back, if the wrong thickness of spacer plate was used & the piston was hitting the dome, the resulting problems listed I can understand probably are happening.
A normal standard thickness of spacer plate for this cylinder kit, should have been a 4.8mm thick plate & two base gaskets, which I understand now was not included in the kit.
One thing that might need to be checked, maybe for other than to thin of a spacer plate being used, is if by chance the sleeve has dropped in the cylinder, which sometimes can happen on the 250R aftermarket cylinders, not a regular thing on all of them, but will happen in a few.
If that has happened, then there will be a greater amount of clearance between the head dome gasket surface & the top of the sleeve, so it could be the inner o ring not sealing as it should & could end up with a coolant leak into the bore.
Those o rings can be a pain at times, trying to get them to stay down in the groove when installing the head, so that maybe could have been some of the problem as well.
Not uncommon when installing the head & torquing the head down, to shiver off a thin piece of the inner o ring, which is probably what that thin thing is.
Its not good either way & the o ring needs to be replaced if that does happen.
Another thing I would like all of you take note of, in the pic of the cylinder, take note of that front coolant passage over top of the exhaust port. I had no part in that machining of that area & like I mentioned, all I did was the cylinder porting & bore job.
This was a builders cylinder kit sent to me to finish with porting & cylinder boring.
Neil
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sorry neil not tryna say ya did it all was just meaning you did the port work and what not. its my fault for not doing homework properly. i do have the correct spacer here to use. im gona tear it apart right now and take some photos then install the correct spacer and start it up. will let ya know how it goes.. i cant wait to set it up right cause even after i messed up the first time it sure was pretty snappy!!!
Yeah, I know, no problem with that.
I sometimes myself when putting in a reply, get words mixed up & they sound like they mean something else.
Main thing is, where its spelled words right or not, as long as you get the point across its ok with me. Some think everythings got to be done like a collage professors doing it, but hey, thats their problem not mine.
If you think that piston was slapping the head, you for sure need to replace it & if you ran it like that, there could be damage to the crank, rod & main bearings.
Neil
Well, I messed this reply up, must have clicked on edit & my reply ended up in your reply.
Neil
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that piston is pretty busted up, i would get a new one.
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yea I'm looking at those milled coolant passages and I don't see how the front two cylinder studs have enough material around them to not distort when torquing the head down. Are all these ESR cylinders like that? I was considering getting a builders kit in a 72 mm bore so there's more material for the sleeve but I would be concerned that there was no material left around the water jacket area like this.
I might just big bore a stock jug
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i see the same thing and also wondered that. i called eddie and he said it would not be a problem and they stand behind it 100%!! he said if it fails he will replace it.. sounds good to me
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theres a old saying. measure twice cut once . its bite me in the ass a few times but if you dont let the same dog bite you twice you should be good :biggrin-new:
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yea i gotcha.. i installed the 5mm spacer with a .020 gasket and a .040 havent dome a squish test yet but will soon.. have rode it down the road a couple times today.. a lil choppy past 1/4 throttle.. i have to play with jetting. may do that this weekend.. also i was doin donuts in my driveway and when i cane back to park it my resevoir bottle on my shroud was bubbling like it was boiling.. i need to get a gauge cause this thing is running really hot!!! which i have heard is an issue with these esr cylinders.. i have a oversize fluyidine rad and engine ice/water 50/50..
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I wonder if your dome isn't seating well now and pressurizing the coolant system or you're super lean?
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You need to slow down and make sure everything is right before you start blasting down the road and doing doughnuts in the driveway.
Did you get a new piston? Did you check squish? Did you perform a leak-down test? Do you know what the compression is? What fuel are you running?
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yea I'm looking at those milled coolant passages and I don't see how the front two cylinder studs have enough material around them to not distort when torquing the head down. Are all these ESR cylinders like that? I was considering getting a builders kit in a 72 mm bore so there's more material for the sleeve but I would be concerned that there was no material left around the water jacket area like this.
I might just big bore a stock jug
The coolant holes do not need to be as large as the ones pictured. If they had 1/2 the area they would still be too large. The size of these holes has nothing to do with the engine overheating and blowing coolant out of the radiator overflow unless the inner o-ring is leaking combustion pressure into the cooling system. The head is suppose to restrict and or control the coolant flow through the cylinder and into the head.
If the coolant is boiling in the radiator, the problem IS NOT IN THE CYLINDER. The cylinder is getting rid of the heat into the coolant but the cooling system is not getting rid of the heat from the coolant.
Making the coolant passages as large as the ones pictured does compromise the rigidity and strength of the top of the cylinder. Reducing the amount of aluminum around the studs and head gasket area will make the bore distort more when the head is torqued. The bore will also experience more distortion and then relax ever time the engine fires when the combustion pressure causes the head to pull on the head studs.
Distortion of the bore when big bore sleeves were installed into the OEM 250 cylinders was one of the main reasons the aftermarket 310 big bore cylinders were created 15 to 20 years ago. Making new casting allowed the cylinder manufactures to move the head studs farther away from the bore and increase the strength (amount of aluminum) in the area where the studs anchor into the upper cylinder. Now we have increased the bore size on these 310 casting to the point that now we are back to some of the original problems we had with the big bore OEM cylinders
I do not see why the manufacturers and engine builders keeps changing the size of these coolant passageways in the cylinder trying to reinvent the wheel...this part of the cylinder is not rocket science
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You need to slow down and make sure everything is right before you start blasting down the road and doing doughnuts in the driveway.
Did you get a new piston? Did you check squish? Did you perform a leak-down test? Do you know what the compression is? What fuel are you running?
well not so much blasting.. i havent really gotten past half throttle or 3rd gear. just putting around mostly.. i still have the same piston.. will check squish today when i get home.. leak down test was good. no leaks and held 6 psi for 10 mins.. i cant find my compression tester at all. i think i left it at the dunes.. so dont mnow on that.. i run 110 sunoco with 32:1 honda hpu.. i know i need to check compression and squish and perform a uccr also..
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i think i may be loosing coolant somehow.. i filled my radiator up to the top and my overflow half full this past weekend.. now i cant see any fluid in the rad and my over flow is empty.. just dont know where its going. i barley have 45 to an hour tops on this bike. and thats just putting around.. wierd!! i am still waiting on some more o-rings from esr so i can change those out on the top.. should the oring just lay in the grooves really easy or should they have to be stretched just a lil to get em in there? my lay in super easy and i have to push em down in cause one lil area pops up as if its to big. that may be my problemo...
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i think i may be loosing coolant somehow.. i filled my radiator up to the top and my overflow half full this past weekend.. now i cant see any fluid in the rad and my over flow is empty.. just dont know where its going. i barley have 45 to an hour tops on this bike. and thats just putting around.. wierd!! i am still waiting on some more o-rings from esr so i can change those out on the top.. should the oring just lay in the grooves really easy or should they have to be stretched just a lil to get em in there? my lay in super easy and i have to push em down in cause one lil area pops up as if its to big. that may be my problemo...
You are going to continue to have problems until you take the time to check everything and do it right instead of jumping like pop corn popping. How can you expect the o-rings to be possibly sealing when you were holding remnants of an o-ring in your hand in one of the pictures.
If the piston is hitting the head how long do you think the Wiseco crank is going to take the abuse? If the piston is hitting the head, the piston will sometimes lift the head enough to allow the head gasket or o-rings to leak?
If there are cracks in the piston, why are you taking the chance of turning the whole engine into junk when the skirts break off the piston?
How can you expect the engine to stay cool "just putting around"?
Get some help from someone that is not so impatient and willing to take the time to find ALL OF THE PROBLEMS before you put it back together.
The problems you are having are very basic and should not require someone with very much experience to solve the problem
Why ask for help if you are not willing to follow anyone's advice?
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Amen to that. I would seriously pull that motor out of the frame, drop it off at a competent engine builder or someone who really knows what they are doing and get that thing set up correctly so it lasts.
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the piston isnt hitting the head any more i have the right size spacer in there now. i have taken my time with the engine i just didnt have the correct parts from esr to begin with. so i tried to make due with what i had. i am taking everybodys advice on what they say and paying attention to what im doing. thats why im figuring out smaller problems as i go. i have to put the damn thing together to see what is wrong other wise i wont know. i cant just guess and say oh well im gona have coolant leaking from the head.. or oh im leaking coolant somewhere.. only way to know is to assemble the engine and run it.. also i cant haul ass down the road cause im still in the break in process so what should i do to see these problems jerry? im listening to your advice but your telling me my water passages are to big as if i can control that.. i am more than capable of installing this engine it isnt my first engine rebuild but it is my first o-ring head rebuild.. i need advice on the questions im asking jerry not smart ass answers that try n chop me down like im an idiot!! im a very respectful guy thats tryna learn. not be talked to like a child..
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Amen to that. I would seriously pull that motor out of the frame, drop it off at a competent engine builder or someone who really knows what they are doing and get that thing set up correctly so it lasts.
i can build the bike dude. im just missing small key parts. i think i have the wrong o-rings. do the orings just fit in the grooves easily or do they have to be stretched a lil? mine sit in to easy i think. thats where my issue is
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(http://global3.memecdn.com/facepalm_o_23376.jpg)
you put the entire engine back together and rode it around with a piston that is cracked in several places due to an hour of riding it with the piston smashing into the head every stroke.
you seem to not understand the stresses caused internally by this and the issues with running a piston that is broken in several places...... this is what you should focus on. not throwing it all back together so you can spin cookies in the driveway. this is what they are trying to tell you.
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i can build the bike dude. im just missing small key parts. i think i have the wrong o-rings. do the orings just fit in the grooves easily or do they have to be stretched a lil? mine sit in to easy i think. thats where my issue is
They need to fit in the grooves easily without popping out of the grooves. Because of this, as I think Dave also stated earlier in the thread, the orings may need to be stretched just a bit. This is normal.
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alright im gona order a new piston.. i understand what your saying. thats my fault for not realizing the cracks were that much of an issue. i just read all the posts in this thread and i missed a couple the first time around when somebody said get a new one.. ill do that
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They need to fit in the grooves easily without popping out of the grooves. Because of this, as I think Dave also stated earlier in the thread, the orings may need to be stretched just a bit. This is normal.
ok thanks man.. thanks for not bashing me for tryna learn something!!
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new fresh o-rings will need to be stretched a little from my experience with them. Seems like more times than not, the inner o-ring more than the outer. It is pretty common for the o-rings to get those little stringy deals you saw on them this is from the o-rings being squished down when the head is torqued. IT can be worse if the o-ring groove is not cut wide enough, but my guess your's is. One other way to allievate some of this as well is to lube the o-rings like someone mentioned on here. Any kind of paste type lube works. I use silcone type lubricant on mine. If the o-rings aren't don't have alot of material taken off them (like your's have had) they can be reused and it's common for them to seem larger than the area they are filling. The lube also helps hold them in place while you are getting the head put on.
Take your head off and see if you have a cut o-ring meaning torn all the way through. if this isn't the case, put a straight edge accross the top of the cylinder and see if the cylinder sleeve dropped down a bit this would make for the inner o-ring not to seal. If this isn't the case and you are still loosing water, you will need to pressurize your cooling system on the motor and see what's going on. you would do this the same way you pressure test your motor. I don't know much about these ESR cylinders but I have had Pro-X 78 mm bore cylinders leak around the exhaust port and into the pipe cold so once everything heats up, it would get worse.
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awesome!! the orings are still in good condition. there is no damage to either of them. it was just weird to me that they just laid right down in there. its my first time messing with with them so just didnt know. heard stories of pol having a hard time keeping them in the grooves as if they would be to tight and keep popping out. when i get home i will check out the sleeve and take some pics so you guys can see.. i know i dont have much patience but i am taking note of what you guys are saying.. would still like some help on this thing. i think once i get the new piston gaskets and seals i will be good. will also check out the rad.. bought it from a guy that said it worked.. will see
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the piston isnt hitting the head any more i have the right size spacer in there now. i have taken my time with the engine i just didnt have the correct parts from esr to begin with. so i tried to make due with what i had. i am taking everybodys advice on what they say and paying attention to what im doing. thats why im figuring out smaller problems as i go. i have to put the damn thing together to see what is wrong other wise i wont know. i cant just guess and say oh well im gona have coolant leaking from the head.. or oh im leaking coolant somewhere.. only way to know is to assemble the engine and run it.. also i cant haul ass down the road cause im still in the break in process so what should i do to see these problems jerry? im listening to your advice but your telling me my water passages are to big as if i can control that.. i am more than capable of installing this engine it isnt my first engine rebuild but it is my first o-ring head rebuild.. i need advice on the questions im asking jerry not smart ass answers that try n chop me down like im an idiot!! im a very respectful guy thats tryna learn. not be talked to like a child..
I am sorry if you think I was talking down to you. Sometimes teachers have to take drastic measures to get a students attention and make them stop and think.
I still believe that you are taking the wrong approach by "figuring out the smaller problems as I go" by putting the engine back together without taking a few simple measurements. Taking few simple measurements would have taken all of the guess work about knowing if the coolant leaks were due to something wrong with the o-rings, the o-ring grooves, the flatness of the head and cylinder, if the piston was hitting the head or something was wrong with the cooling system. You can take all of those simple measurements in a lot less time than it takes to take the top end off and put it back on.
Running the engine to see if the piston is still hitting the head will tell you just that..........the piston is not hitting or it is still hitting. If the piston is not hitting, you still do not know it the piston to head clearance is where it is suppose to be. It takes about 10 minutes to take a piston to head measurement. If the piston to head clearance is too wide it can also cause o-ring destroying detonation even though the compression is lower with excessive piston to head clearance.
If you are using the correct o-rings, the o-ring grooves are machined to the correct dimensions and the o-ring is laying in the grooved relaxed, those thin rubber slivers WILL NOT BE SHAVED OFF OF THE O-RINGs. Any time ANY SLIVERS ARE SHAVED OFF THE O-RING during installation there is potential for the o-ring to leak. O-rings getting shaved is an indication that some dimensions are wrong or there was careless assembly.
It will not hurt an engine during break-in to ride the bike 25 to 40 MPH, where there will be plenty of air going through the radiator, as long as you are not trying to run 40 mph in 2nd gear.
The comments about machining the coolant passages too large, was aimed at the engine builders and manufactures that are grabbing at the wrong straws trying to fix heating issues by performing this machine work.
I know that you cannot do anything about the large coolant passageways that were already in the top of your cylinder, that is why I said that the large coolant passageways are not responsible for you loosing coolant but may cause other problems.
It is the small details that separate the budding engine builder from the veteran builders. Small details are often over looked when one is in a big hurry and or not properly equipped for the task at hand.
Again, I sorry if you think that I was trying to make you look like an idiot.
Jerry Hall
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I am sorry if you think I was talking down to you. Sometimes teachers have to take drastic measures to get a students attention and make them stop and think.
I still believe that you are taking the wrong approach by "figuring out the smaller problems as I go" by putting the engine back together without taking a few simple measurements. Taking few simple measurements would have taken all of the guess work about knowing if the coolant leaks were due to something wrong with the o-rings, the o-ring grooves, the flatness of the head and cylinder, if the piston was hitting the head or something was wrong with the cooling system. You can take all of those simple measurements in a lot less time than it takes to take the top end off and put it back on.
Running the engine to see if the piston is still hitting the head will tell you just that..........the piston is not hitting or it is still hitting. If the piston is not hitting, you still do not know it the piston to head clearance is where it is suppose to be. It takes about 10 minutes to take a piston to head measurement. If the piston to head clearance is too wide it can also cause o-ring destroying detonation even though the compression is lower with excessive piston to head clearance.
If you are using the correct o-rings, the o-ring grooves are machined to the correct dimensions and the o-ring is laying in the grooved relaxed, those thin rubber slivers WILL NOT BE SHAVED OFF OF THE O-RINGs. Any time ANY SLIVERS ARE SHAVED OFF THE O-RING during installation there is potential for the o-ring to leak. O-rings getting shaved is an indication that some dimensions are wrong or there was careless assembly.
It will not hurt an engine during break-in to ride the bike 25 to 40 MPH, where there will be plenty of air going through the radiator, as long as you are not trying to run 40 mph in 2nd gear.
The comments about machining the coolant passages too large, was aimed at the engine builders and manufactures that are grabbing at the wrong straws trying to fix heating issues by performing this machine work.
I know that you cannot do anything about the large coolant passageways that were already in the top of your cylinder, that is why I said that the large coolant passageways are not responsible for you loosing coolant but may cause other problems.
It is the small details that separate the budding engine builder from the veteran builders. Small details are often over looked when one is in a big hurry and or not properly equipped for the task at hand.
Again, I sorry if you think that I was trying to make you look like an idiot.
Jerry Hall
i apologize if im sounding like a dick head!! I really am not just want to learn and fix on my bikes. I do need more patience on building these things.. I have ordered a new piston and will take the right steps when assembling. I understand what you are tryna say it just pisses me off when ppl say i cant do something. Im more than capable of building a bike. Just tryna learn and the only way to do that is to work on the dang thing. Thanks for all your help so far and hope you can still help if i have any more questions.