Yes.Yuriy said:
Make sure you keep track of the little plastic washers with the clips.
They should all be the same. I think the spec sheet should have the stock setting. These screws adjust the amount of fuel/air the engines gets at idle.
There is no adjustment for the air jet but you can take it out for piece of mind, I usually only blow air through it. This is the jet that introduces air to the idle circuit above. The screw on the bottom adjusts how much of the idle air/fuel mixture enters the motor, the air jet controls the amount of air in the idle mixture.
Thank you for the quick response. I will keep track of the plastic washer on the needle clip, and set the bottom screws to 1 1/8 turn on all three carbs. Getting a little bit on the tangent here from our discussion, I would like to ask you a question that came up during a heated debate between my friend and me. Is there a reason that these engines (newer engines in general) use a separate carburetor for each cylinder, why not just have one big carb feeding all cylinders (cheaper, easier to maintain and adjust)?
I think you'll find it boils down to a performance issue. Three carbs make more power because they let more air in. using three smaller barbs allows better throttle response etc. than one large carb. Think of the 2 barrel to 4 barrel comparison between V6 or V8 engines.
That makes sence thank you.
98 srx
98s had some crank timing problems. if you have crank redone tell them to make sure its in phase or time, each cylinder is at top dead center when it needs to be.
98s had some crank timing problems. if you have crank redone tell them to make sure its in phase or time, each cylinder is at top dead center when it needs to be.
Do you think that thermostat failure could have cased this overheating problem or would I see different damages if the thermostat would give out? Also please take a look at the air box does it look stock, is it missing anything. In addition I posted the pictures of the overheated cylinder how does it look?
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if the thermostat would have stuck closed the heads will literally turn black on these engine when run that HOT to cause piston failure.
Airbox looks all stock, not missing anything
cylinder looks that way from the lean condition and detonation is what beat up the head, detonation acts like a little pick(note the liitle dimples and such on piston outer surface, head will be the same way) hammer pounding between the head and piston, its a explosion at the wrong time and this is happening when the crank is bringing the piston up to tdc and also after tdc, thsi is what wrecked your conn rod bearing. Its caused by excessive heat from either too lean(air leak from crank seal) or too low octane fuel, but judging by the other 2 pistons the fuel was ok and jetting was ok as well, they look pretty good.
Airbox looks all stock, not missing anything
cylinder looks that way from the lean condition and detonation is what beat up the head, detonation acts like a little pick(note the liitle dimples and such on piston outer surface, head will be the same way) hammer pounding between the head and piston, its a explosion at the wrong time and this is happening when the crank is bringing the piston up to tdc and also after tdc, thsi is what wrecked your conn rod bearing. Its caused by excessive heat from either too lean(air leak from crank seal) or too low octane fuel, but judging by the other 2 pistons the fuel was ok and jetting was ok as well, they look pretty good.
Thank you, is this cylinder reusable? As soon as I get the motor out I will post the seal and crank pictures.
The jet numbers don't look consistent with the TY tech page is that ok? According to the owner these jets were set up this way from the factory, is that possible (why would factory use different jets)? Also is the larger number on the jet means more fuel it will pass though (exmpl 148.8 jet will pass more fuel than 146.3 jet).
maybe yes and maybe no on the cylinder
youll need to remove the head and check and see if any of the plating(nicasil) has been damaged in the cylinder, if it has dull smeared aluminum on it it can be removed with muratic acid, now be very,very carefull with this stuff as it eats aluminum and lets off a toxic vapor. What you do is lay the cylinder on the bench so that the smeared(melted) aluminum is on the bottom, i use a eye dropper to drip the muratic acid on the aluminim spot, it will bubble and turn dark grey. I wear a mask and gloves to do this.
You will have to keep dripping it on there for it to remove the old piston material, it will not harm the plating 1 bit, it only eats aluminum, so dont get it where you dont want it. BE CAREFULL!!
Any how if the plating isnt chipped, flaked off around the port edges the cylinder will be able to be lightly honed with 240-280 grit stone and reused with no problem, if this is something you dont want to handle let me know, I will help you get it repaired. do this all the time, fixing,repairing sled engines.
whatever the manual says for jets is what would come in it stock, if not the dealer or someone changed them. the larger the number the more fuel it flows, you are correct.
youll need to remove the head and check and see if any of the plating(nicasil) has been damaged in the cylinder, if it has dull smeared aluminum on it it can be removed with muratic acid, now be very,very carefull with this stuff as it eats aluminum and lets off a toxic vapor. What you do is lay the cylinder on the bench so that the smeared(melted) aluminum is on the bottom, i use a eye dropper to drip the muratic acid on the aluminim spot, it will bubble and turn dark grey. I wear a mask and gloves to do this.
You will have to keep dripping it on there for it to remove the old piston material, it will not harm the plating 1 bit, it only eats aluminum, so dont get it where you dont want it. BE CAREFULL!!
Any how if the plating isnt chipped, flaked off around the port edges the cylinder will be able to be lightly honed with 240-280 grit stone and reused with no problem, if this is something you dont want to handle let me know, I will help you get it repaired. do this all the time, fixing,repairing sled engines.
whatever the manual says for jets is what would come in it stock, if not the dealer or someone changed them. the larger the number the more fuel it flows, you are correct.
You are talking about the actual cylinder walls not the top cylinder cover, correct. I have to check out the cylinder walls for aluminum deposits and if I find some (deposit) apply muratic acid on the deposit and let it dissolve the aluminum. After the reaction takes place just wipe of whatever is left with a rag, correct?
blue missile
New member
those look just like my hauck growlers
blue missile
New member
just remember you have a 9 year old sled with 1600 mi on it. im a firm believer that the more you use the longer it will last. ever rember going to look at a used vehicle and hearing a little old lady only drove it to the grocery store and church on sunday and to the hardware store to buy a hammer(sorry nosboy i had to), and usually it looked good but was the worse piece of junk on the road.
Well I finaly pulled the engine a part and here are few pictures of what I found inside. I couldn't really find any damage on the crank other than the missing bearing on connecting rod #3. Any comments, could the bearing disaseble due to crank being out of tolarance (this crank was not repaired prior to me getting it)
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I cant really give you any information based on the pics, hard to see from just a pic if a crank seal is worn, but usually inside they will have either rubber,dr particles or have black gooey substance all insie the lips.the crank you will know right off the bat if its out as who ever is gonna fix it can put it in a set of 'V" blocks and check the run out.
Since the other two pistons are good do I have to replace them (to get the matching weighted and balanced set) or can I get away with changing one piston and all piston rings. The pistons will be different weight but will that matter? Thank you.
Your already there, two more piston, rings, circlips, needle bearings is not all that much more at this point...send the crank out to a shop...I hear C.B. performance does great work...then lightly hone the cylinders and put in the new pistons & check the clearences with a feeler gauge...if all is good, then start re-assembly...good luck & keep us informed...cheers
with only 1600 miles it wont need the other 2 pistons replaced, but I would install new rings that way you do start off fresh with all new rings in 3 holes. The pistons and stuff are not exactly weight matched stuff from the factory, they all just fit in a tolerence, so you can just buy another yamaha piston and replace the bad one, not a problem.
I pm'd you the number for northern crank, they do excellant work and it will be right when you get it back. I would ask them to weld the crank pins while they have it on the truing blocks, this way the crank will be updated and not get out of phase or get excessive run out in the future, once they are welded the 98 cranks were just fine.
I pm'd you the number for northern crank, they do excellant work and it will be right when you get it back. I would ask them to weld the crank pins while they have it on the truing blocks, this way the crank will be updated and not get out of phase or get excessive run out in the future, once they are welded the 98 cranks were just fine.
I have talked to some people and they specifically recommended using OEM Yamaha pistons because “they work better with the cylinders”. What is your input on that can I use different manufacture pistons Wiscos or other on line stuff (maybe good used piston). How about the ring will I have to purchase the ring from Yamaha as well or online stuff will work for me? Also during the disassembly I removed the water pump, oil pump and pistons. When I start the assembly should I replace oil pump, water pump, and cylinder gaskets and pistons circlips (for the good two pistons). In addition, I am planning to adjust the power valves, once I remove them will I need new gaskets to put them back on? In addition the bottom section of the block has two microscopic cracks from connecting rod hitting it, people advise to grind them a bit and clean the surface than put some JB weld on, any comment on that? Thank you.