400 top end rebuild
#1
12-20-2001, 10:34 AM
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For those of you who don't breathlessly read every reply I make to other people's threads, let me inform you that I have just recently done a top end rebuild on my 400 Xplorer. I will detail the procedure, as well as mention any tricks or shortfalls I have discovered on hte way.
The reason I did this was preventive maintanence, so to speak. I had 5200 miles on my Xplorer, coming pretty close to the lower end of the mileage range of when the stock pistons will start to crack, sometimes sending pieces of the skirt into the main 'guts' of the engine. My top end rebuild was pretty simple, just replaced the piston and rings, and had the cylinder honed to match. I went to a Wiseco piston for their reputation for toughness (not cracking a part of the skirt off like the stock Polaris ones do).
My first step was to call Ritter Cycle for the parts. I could have gotten the piston about anywhere, but chose Ritters because of good service I had in the past. I feel I made a good choice because he was able to send me a new piston, as well as a cylinder he had bored to match it, and would refund me core charge when I sent back my cylinder to him. It did cost me an extra 3% refund fee (through my credit card company, not Ritter Cycle) for that, but I felt it was a small price to pay. I did NOT want my engine sitting 'open' for the several days it would take to get my own cylinder back. My shop is also used for machinery storage, and a tractor can stir up quite a bit of dust [img]i/expressions/face-icon-small-smile.gif[/img]
I decided to have the cylinder honed due to cost, as well as durability. The rebuild will last longer if the cylinder is honed to the EXACT clearances the piston manufacturer recommends. No fear of initial looseness, or scoring from it being too 'tight'. Besides, the $35 Ritter's charged for honing isn't too much to pay to get maximum life out of a $100 piston.
When I got the box, I washed out the cylinder twice with warm, soapy water. This is to get all the honing oil & residue out. After rinsing & letting it dry, I coated the inside with the gold injector oil. I kept adding a little oil, and using a new rag, until the rag came out perfectly clean (can't be too clean fitting a piston to the bore). I know a guy who used a dishwasher to do this - but only once. Seems his wife didn't like the dishes smelling like oil! [img]i/expressions/face-icon-small-wink.gif[/img]
The work on my machine was pretty straightforward. Take off the seat, side panels, front fenders & gas tank. You will also need to remove the front rack to get this off. One word of advice, if you ride around until you need reserve, you will have less gas to siphon out, or catch when you unhook the fuel line. The fuel line farthest forward is the reserve line. If you remove that from the shutoff valve, you can catch the gas in a can, and the tank will then be almost completely dry. Unhook the other line, too, before you remove the tank. All this is pretty straightforward, just removing bolts, wiggling the fenders or whatever, and looking for another bolt if it doesn't come right off.
IF you turn the handlebars one way or another, and are VERY careful of the choke lever (remove the key) you can just BARELY weasel the front fenders over the handlebars without removing them. It helps if you have a space heater on the fenders or do this on a warm day, so the plastic is more flexible. Just watch the choke lever, I broke the end off mine (boo-boo that cost me $8) You could even unscrew the little ring & push it into the headlight pod, just to be safe.
Now drain the anti-freeze (you could have done it sooner, but the hoses are easier to get to with the fenders off). Remove the springs holding the exhaust on, and pull the header pipe out of the way. Now remove the little bolts that bolt the carb boot to the intake side of the cylinder. It might be easier to do if you remove the top engine mount now (it needs to come off anyway). You can remove the airbox now if you need the room, but I just worked around it myself.
Now loosen the 4 nuts at the bottom of the cylinder. This will take a 14MM wrench, and a good one. One of the nuts is hard to get to, but there IS room. It might help to remove the exhaust pipe mount off the cylinder, if you need the room. Be sure to remove the temp sensor wire & plug wire.
Option 2 - take the head off first, if you want. Just pop off the temp sensor & plug wire & remove the nuts that hold the head. You can do this if you want to look inside the engine without takinig it all apart.
The cylinder just lift off the piston. Just before it comes out, wrap a rag around the connecting rod. This will keep junk out of the crankcase, and cushion the rod/case as you clean off any gasket residue.
Remove the piston. Pop the wrist pin clips out, and push out the pin. I had to tap gently on mine to get it out. If you need to do this, support the back of the piston as best you can, to not put strain on the rod or rod bearing.
Put the rings on the new piston. Just be careful, and be sure the markings go to the TOP of the piston. There is a little peg in each piston groove, be sure the ends of the ring meet at that peg.
Pop in the new piston (and rod bearing, if you got one - I did). Put one of the retaining clips in before you start, it is easier on the workbench, and put just a dab of oil on everythng before assembly. Now put in the other clip. A good pair of needle-nose pliers helps. Watch that sucker, it can be a bugger to get in, and CAN go flying (hold your thumb over it, so if the pliers slip, you will catch it. A buddy is a great help right here)
Swap the reeds to the new cylinder. Again, clean out any gasket material off the reeds, and install with a new gasket. Can't goof this up, it only fits one way!
Make sure the ends of the rings are at the little 'pegs' in the piston groove, squeeze the rings together (you can do this by hand) and lower the cylinder into place. Be sure you have a light coating of oil in the bore before you do this. Now tighten down the 4 bolts. Torque them to specs. There is one nut I couldn't reach with a torque wrench, so I pulled on another nut with a regular box end to get a 'feel' for how tight it was, and tightened that one as close to it as I could. You will know which one I was talking about when you get to it. Remember to tighten the nuts finger tight, then follow the torque pattern, and only go about a half turn at a time on any one, then move on. Repeat until proper torque is met. You did remember to put on a new gasket, right?? [img]i/expressions/face-icon-small-smile.gif[/img]
New head gasket, and re-install the head. Be sure there is no old gasket stuck to the head. Don't worry about the old cylinder, that is Ricks problem, now [img]i/expressions/face-icon-small-wink.gif[/img]
Install the head like the cylinder. Finger tighten the nuts, then 1/2 turn at a time, following the torque pattern, until tight. Re-connect the wires, the airbox, and everything else you took off. If you waited until now to install the exhaust flange to the cylinder, do it now. Leaving it off gives you just a teeny bit more access to that hard to get at cylinder base nut.
Hook up the hoses, and loosen the little bolt on the head with the phillips screw slot in the head. Fill the radiator up, and leave the bolt loose until air bubbles quit flowing out. Be careful not to overtighten it, as it is a hollow bolt.
Put your gas tank, fenders, exhaust, and such back on. Leave the front rack off so you can get to the radiator. I put 4 gallons of gas, and 6 oz. of injector oil in the tank for break-in. You only have to do this for the first tankful.
Fire up the engine, and keep an eye on the radiator. Keep adding coolant as the water level goes down (it will just a little).
Put the cap on, and ride around for about 5 minutes or so. Let it cool down good, and re-check the radiator. It should be plumb full. If not, add more, and check the overflow. Ride another 5 minutes, and check again. Once the level stabalizes, put on the front rack & you are DONE [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img]
All that is left is break-in. Rick said to take it VERY easy the first 1 1/2 hours, and fairly easy another 2 1/2. Once you get 4 or 5 hours, go out and have fun. Try not to have sustained full-throttle for maybe another 5 hours or so, and you are set!!
I am open to any questions.
On a 1-10 difficulty scale, I call this one a 6. Not too tough, just take your time, and keep everything clean. There are a few bolts that are hard to get at, and will take patience to re-align (the airbox boot will take patience, but not much mechanical skill). Nothing really jumps out at you under spring tension, except maybe the piston clips.
Farmr
The reason I did this was preventive maintanence, so to speak. I had 5200 miles on my Xplorer, coming pretty close to the lower end of the mileage range of when the stock pistons will start to crack, sometimes sending pieces of the skirt into the main 'guts' of the engine. My top end rebuild was pretty simple, just replaced the piston and rings, and had the cylinder honed to match. I went to a Wiseco piston for their reputation for toughness (not cracking a part of the skirt off like the stock Polaris ones do).
My first step was to call Ritter Cycle for the parts. I could have gotten the piston about anywhere, but chose Ritters because of good service I had in the past. I feel I made a good choice because he was able to send me a new piston, as well as a cylinder he had bored to match it, and would refund me core charge when I sent back my cylinder to him. It did cost me an extra 3% refund fee (through my credit card company, not Ritter Cycle) for that, but I felt it was a small price to pay. I did NOT want my engine sitting 'open' for the several days it would take to get my own cylinder back. My shop is also used for machinery storage, and a tractor can stir up quite a bit of dust [img]i/expressions/face-icon-small-smile.gif[/img]
I decided to have the cylinder honed due to cost, as well as durability. The rebuild will last longer if the cylinder is honed to the EXACT clearances the piston manufacturer recommends. No fear of initial looseness, or scoring from it being too 'tight'. Besides, the $35 Ritter's charged for honing isn't too much to pay to get maximum life out of a $100 piston.
When I got the box, I washed out the cylinder twice with warm, soapy water. This is to get all the honing oil & residue out. After rinsing & letting it dry, I coated the inside with the gold injector oil. I kept adding a little oil, and using a new rag, until the rag came out perfectly clean (can't be too clean fitting a piston to the bore). I know a guy who used a dishwasher to do this - but only once. Seems his wife didn't like the dishes smelling like oil! [img]i/expressions/face-icon-small-wink.gif[/img]
The work on my machine was pretty straightforward. Take off the seat, side panels, front fenders & gas tank. You will also need to remove the front rack to get this off. One word of advice, if you ride around until you need reserve, you will have less gas to siphon out, or catch when you unhook the fuel line. The fuel line farthest forward is the reserve line. If you remove that from the shutoff valve, you can catch the gas in a can, and the tank will then be almost completely dry. Unhook the other line, too, before you remove the tank. All this is pretty straightforward, just removing bolts, wiggling the fenders or whatever, and looking for another bolt if it doesn't come right off.
IF you turn the handlebars one way or another, and are VERY careful of the choke lever (remove the key) you can just BARELY weasel the front fenders over the handlebars without removing them. It helps if you have a space heater on the fenders or do this on a warm day, so the plastic is more flexible. Just watch the choke lever, I broke the end off mine (boo-boo that cost me $8) You could even unscrew the little ring & push it into the headlight pod, just to be safe.
Now drain the anti-freeze (you could have done it sooner, but the hoses are easier to get to with the fenders off). Remove the springs holding the exhaust on, and pull the header pipe out of the way. Now remove the little bolts that bolt the carb boot to the intake side of the cylinder. It might be easier to do if you remove the top engine mount now (it needs to come off anyway). You can remove the airbox now if you need the room, but I just worked around it myself.
Now loosen the 4 nuts at the bottom of the cylinder. This will take a 14MM wrench, and a good one. One of the nuts is hard to get to, but there IS room. It might help to remove the exhaust pipe mount off the cylinder, if you need the room. Be sure to remove the temp sensor wire & plug wire.
Option 2 - take the head off first, if you want. Just pop off the temp sensor & plug wire & remove the nuts that hold the head. You can do this if you want to look inside the engine without takinig it all apart.
The cylinder just lift off the piston. Just before it comes out, wrap a rag around the connecting rod. This will keep junk out of the crankcase, and cushion the rod/case as you clean off any gasket residue.
Remove the piston. Pop the wrist pin clips out, and push out the pin. I had to tap gently on mine to get it out. If you need to do this, support the back of the piston as best you can, to not put strain on the rod or rod bearing.
Put the rings on the new piston. Just be careful, and be sure the markings go to the TOP of the piston. There is a little peg in each piston groove, be sure the ends of the ring meet at that peg.
Pop in the new piston (and rod bearing, if you got one - I did). Put one of the retaining clips in before you start, it is easier on the workbench, and put just a dab of oil on everythng before assembly. Now put in the other clip. A good pair of needle-nose pliers helps. Watch that sucker, it can be a bugger to get in, and CAN go flying (hold your thumb over it, so if the pliers slip, you will catch it. A buddy is a great help right here)
Swap the reeds to the new cylinder. Again, clean out any gasket material off the reeds, and install with a new gasket. Can't goof this up, it only fits one way!
Make sure the ends of the rings are at the little 'pegs' in the piston groove, squeeze the rings together (you can do this by hand) and lower the cylinder into place. Be sure you have a light coating of oil in the bore before you do this. Now tighten down the 4 bolts. Torque them to specs. There is one nut I couldn't reach with a torque wrench, so I pulled on another nut with a regular box end to get a 'feel' for how tight it was, and tightened that one as close to it as I could. You will know which one I was talking about when you get to it. Remember to tighten the nuts finger tight, then follow the torque pattern, and only go about a half turn at a time on any one, then move on. Repeat until proper torque is met. You did remember to put on a new gasket, right?? [img]i/expressions/face-icon-small-smile.gif[/img]
New head gasket, and re-install the head. Be sure there is no old gasket stuck to the head. Don't worry about the old cylinder, that is Ricks problem, now [img]i/expressions/face-icon-small-wink.gif[/img]
Install the head like the cylinder. Finger tighten the nuts, then 1/2 turn at a time, following the torque pattern, until tight. Re-connect the wires, the airbox, and everything else you took off. If you waited until now to install the exhaust flange to the cylinder, do it now. Leaving it off gives you just a teeny bit more access to that hard to get at cylinder base nut.
Hook up the hoses, and loosen the little bolt on the head with the phillips screw slot in the head. Fill the radiator up, and leave the bolt loose until air bubbles quit flowing out. Be careful not to overtighten it, as it is a hollow bolt.
Put your gas tank, fenders, exhaust, and such back on. Leave the front rack off so you can get to the radiator. I put 4 gallons of gas, and 6 oz. of injector oil in the tank for break-in. You only have to do this for the first tankful.
Fire up the engine, and keep an eye on the radiator. Keep adding coolant as the water level goes down (it will just a little).
Put the cap on, and ride around for about 5 minutes or so. Let it cool down good, and re-check the radiator. It should be plumb full. If not, add more, and check the overflow. Ride another 5 minutes, and check again. Once the level stabalizes, put on the front rack & you are DONE [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img] [img]i/expressions/face-icon-small-smile.gif[/img]
All that is left is break-in. Rick said to take it VERY easy the first 1 1/2 hours, and fairly easy another 2 1/2. Once you get 4 or 5 hours, go out and have fun. Try not to have sustained full-throttle for maybe another 5 hours or so, and you are set!!
I am open to any questions.
On a 1-10 difficulty scale, I call this one a 6. Not too tough, just take your time, and keep everything clean. There are a few bolts that are hard to get at, and will take patience to re-align (the airbox boot will take patience, but not much mechanical skill). Nothing really jumps out at you under spring tension, except maybe the piston clips.
Farmr
#2
12-20-2001, 10:57 AM
Farmr123,
There are some people on this forum that I do read their posts with much appreciation, and you are one of them. You always seem to do a great job of explaining everything in a manner that is easy to follow.
I am going to assemble mine when everything gets back from Ritter. I do have a few differences........in that I got my piston coated by swaintech, my head is going to be milled, and my flywheel is to be lightened (retaining electric start). I cannot wait to get it back together.
Thanks again,
Waylan
There are some people on this forum that I do read their posts with much appreciation, and you are one of them. You always seem to do a great job of explaining everything in a manner that is easy to follow.
I am going to assemble mine when everything gets back from Ritter. I do have a few differences........in that I got my piston coated by swaintech, my head is going to be milled, and my flywheel is to be lightened (retaining electric start). I cannot wait to get it back together.
Thanks again,
Waylan
#3
12-20-2001, 12:23 PM
You should get a gold star for that post farmr123. You wrote it like it would be something that i would read out of manual. I'm glad that you took the time to write that. I'm sure that it will be helpful to the next person thas has to do a top end job. Only thing that i saw that you might have left out was the ring gap. I never get them too out of spec but some people might bend the ring to get it in and spread the gaps too far apart. Again, it was a great post. It would be great if everyone did that, we wouldn't even need service manuals. We could also cut out the dealership for repairs.
#4
12-20-2001, 12:34 PM
Farmr123,
Did Rick set the ring end gap for you, or is this something that you did? Is your break-in complete? Does the wheeler run the same, or better? Does it rattle when cold/hot/both, or does it sound same as stock? I would like to know any differences you attribute to the wiseco piston and/or rebuild.
Also, did you try to make sure the gaps in the spring clips were in the straight up/down position? I read that tip in the Polaris manual, and also on another forum. I think it ensures that the spring won't get fatigued and break.
Thanks,
Waylan
Did Rick set the ring end gap for you, or is this something that you did? Is your break-in complete? Does the wheeler run the same, or better? Does it rattle when cold/hot/both, or does it sound same as stock? I would like to know any differences you attribute to the wiseco piston and/or rebuild.
Also, did you try to make sure the gaps in the spring clips were in the straight up/down position? I read that tip in the Polaris manual, and also on another forum. I think it ensures that the spring won't get fatigued and break.
Thanks,
Waylan
#5
12-20-2001, 12:42 PM
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Walexa, sounds like you are going to have some FUN when you get yours together. I considered upping the performance on mine, but mine is a 'daily driver workhorse' and I was looking for reliability. Stock, the Xplorer has enough oomph to keep me satisfied. If I was the only driver, I could boost it up a little, and only use the extra power to humiliate my buddies every now and again, but when you have others who drive the thing, often pulling a loaded trailer, I didn't want too much HP to overwhelm the drivetrain. Right now I pull a 700# + trailer with NO problems except that I lube the chain twice as often as when I run empty. Otherwise, you can almost see it stretch.
I don't have it broken in all the way yet, but it does seem to run just a little stronger than it did, which I take as a good sign, especially since it is running pretty strong on the oil (both from the injector, and the oil I added to the gas.
As far as rattle goes, I really can't tell any. Maybe just a hint for the first little bit at start up, then seems as tight as when it was new.
For the record, the crank and rod bearings were still VERY tight, probably almost to new specs yet.
Good point, about the ring gap, Meangreenmachine. I didn't have to worry about that, as Ritter did all the fitting for me (ring gap, piston clearance, and the like. As long as care is used (don't open the rings any more than absolutely necessary to get them on the piston) and you should be OK. I bet if you were scared about that aspect of it, Rick would install the rings for you. There are a lot of things I left out, due to space limitations. If anyone is considering this process, feel free to ask questions while it is still fresh in my mind.
I don't have it broken in all the way yet, but it does seem to run just a little stronger than it did, which I take as a good sign, especially since it is running pretty strong on the oil (both from the injector, and the oil I added to the gas.
As far as rattle goes, I really can't tell any. Maybe just a hint for the first little bit at start up, then seems as tight as when it was new.
For the record, the crank and rod bearings were still VERY tight, probably almost to new specs yet.
Good point, about the ring gap, Meangreenmachine. I didn't have to worry about that, as Ritter did all the fitting for me (ring gap, piston clearance, and the like. As long as care is used (don't open the rings any more than absolutely necessary to get them on the piston) and you should be OK. I bet if you were scared about that aspect of it, Rick would install the rings for you. There are a lot of things I left out, due to space limitations. If anyone is considering this process, feel free to ask questions while it is still fresh in my mind.
#6
12-20-2001, 01:35 PM
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12-22-2001, 01:18 PM
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#9
12-22-2001, 03:57 PM
#10
12-22-2001, 04:39 PM
Farm123, very nice post. Its not too often that someone will post
information as detailed as yours.
I do have one question though. I may have missed it in your post
but did you re-check the head bolt torque after the first 5-10
minutes you ran the engine? It was easier to re-check mine before
I put all my stuff back on. I had to hang the gas tank from a
ceiling joist and add a longer fuel line. After running the engine
for about 10 minutes I re-checked the head torque. Mine was fine!
information as detailed as yours.
I do have one question though. I may have missed it in your post
but did you re-check the head bolt torque after the first 5-10
minutes you ran the engine? It was easier to re-check mine before
I put all my stuff back on. I had to hang the gas tank from a
ceiling joist and add a longer fuel line. After running the engine
for about 10 minutes I re-checked the head torque. Mine was fine!