How To : Remove And Install An Engine

[90GTVert]

Engine Removal And Installation

Steps will vary depending on model and engine type, but the general process should be similar for all scooters.

Removal

I started by removing the screw that holds the battery cover in place. Mine is now a phillips head screw, it used to be a screw with an 8 or 10mm head.


I have to pry the cover up with a flathead screwdriver.


With the cover removed, you can see the battery.


Pull back the covers on the terminals to expose the phillips screws holding the ring terminals on the battery. Remove the negative (usually black) cables first, then the positve cables.


Pull the wires out of the way.


Be careful not to lose the nuts inside the battery's terminals.


I like to reinstall the screws and nuts so I don't lose them.


Now I use the key to remove the access panel. This would normally let you check or fill the oil resevior on a Triton, but I no longer use my oil injection system so I use it to access the spark plug or just to reach through for other tasks.


Then I remove the seat and storage tub for better access.




Now I remove the clamp attaching the airbox to the carburetor, and separate them from each other.






The stock airbox also has 2 bolts holding it to the CVT cover that need to be removed.


With the clamp off and bolts out, the airbox can be removed and put aside.


It's been a long time since it ran, and I can see there is no fuel in my filter.


Remove the clamp and take off the fuel line. It is a good idea to have a catch pan handy even if you think there is no fuel in the line. You may need to clamp this line off with vise grips or a clamp or plug it with a bolt.


Now I disconnect the harness from the auto-enrichener.


I then disconnect the vacuum hose. This is also when you would want to remove the oil injection hose, but I have plugged that port on my carburetor.


Now I create some slack in my carburetor cable to make later steps easier. Here you can see the position of the cable nut and locking nut on the carburetor as I have them adjusted for riding.


Unscrew the locking nut.


Screw the cable nut all the way in.


Remove these screws and carefully pull the cap and throttle valve assembly out of the carb.


Loosen this phillips screw (hard to see for grease) and pull the carburetor from the manifold. Be sure that nothing catches or is still attached.




Get a catch pan and unscrew the float bowl drain screw until fuel flows out of the drain hose at the bottom of the bowl. When the flow of fuel has stopped, tighten this screw back up.


I like to put something in the intake manifold just to be sure no debris finds it's way in.


Now I still need to get the throttle valve off of the cable. Compressing the spring will allow the cable to be pushed downward and then out of the groove in the throttle valve.






Now I just pull the top of the carb off of the cable.


Reinstall the throttle valve and other parts along with the cap and set the carb aside. (I'll show you this process in more detail later.)


Now I remove the spark plug wire.


Then I need to disconnect all cables coming from this harness.








Disconnect the power cable from the starter.


Remove the 8mm head bolt to disconnect the ground wires from the CVT case, being careful not to lose any washers.


Remove the 8mm head bolt holding the rear brake cable bracket on the bottom of the CVT cover.


Compress the rear brake lever (the one shown here, not the one on the handlebars) and remove the nut at the end of the cable so you can pull the cable out of the lever and barrel inside it.




Remove the barrel from the lever and take the spring off of the brake cable so you can pull it out of it's guide in the case.




I reassemble this as well to make sure no parts wander off.


Now I put my scoot up on a stand. This is actually just a stool with a towel over it to help avoid scratching any paint. I just pick it up and place it there, you may want to have a friend help or use another method. Be sure it is secure, you don't want the scoot falling on you. Sometimes I use a ratchet strap for added stability.


I now remove the nut from the bolt going through the frame and motor mount. I leave the bolt in place for now.


I then remove the nut and bolt from my rear shock absorber and move it so it no longer supports the scooter. The scooter will drop when the shock is removed so be sure you are capable of holding it with one hand or have a friend help you here.




Now I use a rubber mallet to tap the motor mount bolt out. Always use rubber so you don't damge your threads. You shouldn't need much force.


Once it is tapped out a little, you can pull it from the other side. When this bolt is removed your engine will drop. Be prepared to support it and be careful.




Now I can set the engine assembly on the work bench for later.


Installation

Now I put my scooter back up on my "lift" and secure it with a ratchet strap this time to show you.


Pivot the engine up with one hand and insert the bolt through the motor mount and frame with the other.




Now I lifted the engine and attached the rear shock.


Now the scooter can come down again.


I then reinstalled the exhaust.


Reconnect the engine harnesses.




Reconnect the wire to the starter.


Slide the carb back into the intake and tighten the clamp to secure it.


Run the throttle cable through the carb top.


Put the spring over the cable and compress it so you can install the throttle valve assembly to the cable.




Install the throttle valve assembly into the carburetor as I showed you before and reattach the carb top.


Reinstall the vacuum line and oil injection line if so equipped.


Reinstall the fuel line and clamp.


Connect the wires to the auto-enrichener.


Slide the airbox back on and install the clamp. I don't have my CVT done yet, so I can't bolt it to that now.


You also want to adjust the slack back out of your carburetor cable now.

Put the rear brake cable back through it's guide.


Install the barrel in the lever and put the spring through, then attach the nut and adjust your brake until it will stop the tire from moving. You will prob need to farther adjust this later.