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Discussion Starter · #1 ·
My utility style fourtrax 350 won't start. For years there was a clacking noise while running that seemed to be in the pass side top of engine. Had valves adjusted but made no difference. Then one day it just won't start. has fuel, fire and compression. I mentioned it to a mechanic buddy and he figured timing chain adjuster was worn out and it jumped it's time. how do I get at the timing chain and gears to set the timing again. I had the adjuster apart and I think it's funked. Do I have to pull the engine? Are there any downloadable service manuals around? I'm new to wrenching on Hondas. Polaris sleds and Mopars are my thing.
 

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Trx 350d....

You will need to thread a wire with the timing chain up through the head again. People use a wire so you don't drop the timing chain.

timing chain.....:)

First remove all plastics, gas tank, and heat shield for the gas tank. Begin by unloosening the twelve 8mm bolts on the cylinder’s headpiece. There is a cross member bolt that runs through the top of the cylinder’s headpiece, remove it using two 14mm wrenches or sockets. Use a 6mm allen key to remove the timing window and a 10mm allen key to remove the cap for turning the crank both on the left side of the case. The timing mark should be top-dead-center in the timing window, just like you were going to adjust your valves, look for the sideways T. A 17mm socket is needed to turn the crank to find top-dead-center. Now you can remove the cylinder’s headpiece and start the internal disassembling process. undefined There is cotter pin on the rear brake master cylinder and a R-clip on the brake pedal itself that need to be pulled out so the pedal can be moved to make room for the next step. The bottom end side case on the clutch side will need to be taken off by extracting the thirteen 8mm bolts. Be sure that your oil is drained before performing this step to avoid a messy spill. In addition, the sending and returning oil lines will need to be disconnected from the case (you will not need to remove the short oil filter bolt toward the middle of the case). When you begin removing the internal components within the motor, be sure to organize a system that arranges your motor’s parts so they components are correctly installed in the proper fashion for reassembly. Tap the edge of the clutch side case with a rubber mallet to free it from the block. Be careful not to ruin the gasket when removing the side case. Use a 10mm socket to loosen the five clutch spring-bolts from the clutch hub assembly. (They have a color resembling brass) The clutch plates will now slide out of the basket and a 27mm socket will be needed to remove the bolt inundefined the center of the clutch basket. A second set of hands help here by keeping the ATV immobilized from rolling. Note that putting the ATV in a high gear will aid in loosening the clutch basket bolt. Next, to the right of where the clutch basket was, you will find a small sprocket for the oil pump. This sprocket will now slide right out of its position, but notice the marking KCY on the outer side of the sprocket for reinstallation purposes. You now will notice a set of sprockets forworking the undefinedoil pump and clutch basket right between the two items. You will also see the timing chain behind them, and a 27mm bolt in front of them. While your second set of hands is there have them hold a 17mm socket on the crank bolt (opposite side) while you loosen the 27mm bolt in front of the sprockets. Look at the top end of the cylinder where you see the camshaft, timing chain, and timing chain sprocket with the two 6mm alan bolts holding the sprocket to the cam. Make sure you are still top-dead-center through the timing window and note the marks on the sprocket. This helps match up the same holes in the sprocket to the same camshaft holes for later assembly. Now, unscrew the 6mm cam/sprocket bolt and rotate the crank to the next cam/sprocket bolt and do the same procedure.



Return to the bottom end of the motor, take out the 10mm bolt holding the left timing chain guide (black), and slide out the guide. Remove the upper timing chain sprocket from the chain, and partially lower the chain so that it creates enough slack to take it off the lower sprocket. When the timing chain is off the lower sprocket, it will freely slide out of the top of the cylinder near the camshaft location. Lower your timing chain down to the bottom sprocket from the top of the cylinder. Reinstall the chain on the lower sprocket first and then the upper sprocket, while making sure your timing marks are lined up the same as before. In order to install the chain, the timing chain tensions adjuster must be loosened. The tension adjuster is located on the right rear, exterior of the cylinder. It extends off the rear of the cylinder wall and has two 8mm bolts on each end and one phillips screw in the middle. Loosen the two bolts to increase slack in the timing chain, and slide the sprocket on the camshaft. Insert the two 6mm allen bolts in the sprocket, and then tighten the two timing chain tension bolts back into place. Begin installing all the parts you removed in an order of last off, first on, using the removal process paragraphs above as your reference guide. And that should do it...wheeeew;)
 

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Discussion Starter · #4 ·
I leaned on the kick start after taking the timing tensioner lifter out. the crank turned some and the cam didn't. How the heck do I make sure I'm timed right putting it all back together with the new cam chain? I can set the crank by its marks, but how do I know about the cam ? I know it's out of wack.
 
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