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Installation and Review: Mountain Performance Inc, Stage 1 & 2 Supercharger

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INITIAL HOSE REROUTING
1. Remove the thermostat housing leaving all 3 large hoses attached to the housing (top hose from Radiator,
side hose engine block manifold and lower hose to lower port on the front heat exchanger). See Figure 3.

2. Unplug & remove the temperature sending unit (don’t loose the copper washer) from the thermostat
housing.


Places the thermostat in my vice to get a good firm grip on it and quickly realized that the metal was so soft is was gouging it.
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Added a towel on both sides to protect it, and unscrewed the sending unit.
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3. Remove and discard the short small hose that was connected to the RH side of the throttle bodies. Note
that the short small hose has 2 different size spring clamps. The larger one is used on the throttle bodies. (Done Previously in Teardown)

4. Heat the thermostat housing with a torch (careful not to melt the hoses). Remove the small silver nipple
from the housing with vise-grips in a twisting motion. See Figure 4.


Ditched the rags so they wouldn't catch on fire and broke out the torch to heat things up. There is a small lip on the bottom of this nipple. Make sure you put the Vise-Grips in this lip or there is a good chance you will collapse the tube rather than extracting it out.
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Once its good and hot start twisting it back and forth to loosen it and then pull up and it will pop right out.
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5. Use red Loctite to coat the small aluminum plug provided. 1 end of the plug is slightly smaller. Install the
end 1st. Hammer the plug into place. See Figure 5&6.

6. Install the M12-1.5mm bolt and copper washer provided in the kit into the thermostat housing where you
removed the sensor. See Figure 7.


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Once its coated and in place
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POUND on it till it goes all the way into the housing.
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And then pound on it some more till it is flush.
And then screw in the new bolt with the coper washer in place
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Finished Thermostat Housing.
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7. Remove the large hose of the RH side of the bulkhead that connects to upper port on the front heat
exchanger and leads to the rear heat exchanger. This is a 2 piece hose. See Figure 8.


The hose on the bottom right is your target for removal.
But I found it easier to just remove both of them.

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Since the lower hose is connected to the heat exchanger in the tunnel, I guessed there would still be some anti-freeze left in there and wrapped it with some towels.
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Sure enough, just as soon as I removed the hose, out came the fluid.
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After it seeped out for a few minutes I was ready to proceed again.
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8. Disconnect and discard the steel joiner, clamp and the straighter of the 2 hoses. Cut 1” from the end of the
hose with tight 90 deg on it. See Figure 9.




The other end of the double hose
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Loosen the clamp and slide in a screwdriver to break it free.
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And this is what you get once it's removed.
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Here is the steel joiner that needs to be removed.
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Last edited:
Measure back ONE INCH.
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I marked it with a White Marker.
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Cut it with a hack saw
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Didn't like the rough edges that the hacksaw left, so I went back and clipped the edges clean with a pair of dikes.
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9. Install this modified hose between the same 2 points where the 2 piece assembly was installed. The 90deg end goes to the front top heat exchanger. Use narrow OEM clamps on both ends. See Figure 10.


Removal and modification were easy and straight forward.
But getting this baby back into place and connected the lower clamp was a bear. The hose just did not want to mate up with the lowercoolent pipe, and when I finally got it on, the clamp didn't want to sit properly around the hose. Turns out there is a small metal brace right behind the hose that was pushing against the clamp trying to stop it for being seated where I wanted it.

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The hose slides into place pretty easily
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Trouble begins when you can't push the hose down onto the tube.
It has to be PULLED down using needle nose pliers.
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I also found it easier to make a small incision on the protective band around the hose to allow the hose to stretch over the tube easier.
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And she is on.
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Reconnecting the hoses on the top was a no brainer.
 
The best thing any 4-sroke yamaha guy can purchase is the rollover valve. Keep the oil in the motor where it belongs... Hey Chris, your going to help make my install a breeze. When your done with Slash send him to utah. I have plenty of root-beer.(decaff):face-icon-small-sho
sorry have to have high octaine
 
10. Remove the OEM pipe style manifold from the front of the engine case. See Figure 11.


Top center is the OEM Pipe Style Manifold that has to be removed and replaced.
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Held in place by a single 5mm Alen Bolt
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Remove the bolt and disconnect the hoses and it slides right out.
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11. Remove the O-ring from the OEM manifold and inspect it for damage. Reinstall the GOOD o-ring onto the new billet manifold. New manifolds had a 3rd hole on the face. This hole is 1/8” NPT. It is plugged when
you use the standard GEMS fuel control. It is utilized when you use our standalone Fuel-Pro™ system.


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12. Install the new billet water manifold. Use the large OD 6mm washer, the small OD 6mm washer and the M6x16mm Flange head bolt provided. NOTE: The Larger washer is next to the bolt head, with the smaller one under it. (It helps to put a dab of silicone between the 2 washers to hold them together for future service). See Figure 12 & 13.


This is the new manifold.
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Slides right into place.
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Inserting the large washer that will hold the manifold in place.
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And the new bolt that holds the washer and locks down the manifold.
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13. Connect the small line coming from the LH side (water pump) to the 45deg nipple on the LH side of the manifold.

14.
Connect the 12mm “U” shaped hose going to the Oil cooler to the 1/2” elbow on the manifold using the OEM worm clamp.

15.
Install the new 8.5” long ¼“ hose provided to the ¼” 90deg elbow in the water manifold. Secure this with the smaller of the 2 OEM spring clamps.

15.5
If using the Fuel-Pro™ controller install Fuel-Pro™’s water temp sensor into the 1/8” npt port on the manifold face.

16. Install the OEM water temp sensor into the new manifold; be sure to reuse the OEM copper seal washer. See Figure 14.


Reconnecting the pre-existing hoses.
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This is the new hose that is supplied in the kit.
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It gets attached and routed beneath the large hose and then back upwards.
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And the last step was supposed to be installing the OEM Temp Sensor, but I did that early on while the manifold was already out of the engine.
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17. Remove the black 14mm oil return hose that led to the side of the OEM oil tank from the engine block just below the oil cooler.




This lower hose is the next one to go.
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Same hose from the side of the engine.
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Possibly the easiest part of the whole project so far.:face-icon-small-hap
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End Result
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PTO INSTALL
18. Remove and discard larger plastic plug in side cover. See Figure 15.


Craked it just a bit and it started to weep, thought I might get a load of oil, but almost none came out.
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19. Remove the RH Side Motor Cover. 1 Black Bolt (marked with a triangular arrow head in the aluminum cover) and 11 Silver Bolts (note position of 1 black bolt) (also note position of the stator wire bracket).


I was VERY SURPRISED that all of these bolts were just FINGER TIGHT!
There was almost NO Torque required on any of them.
Have to think someone at the factory failed to tighten my engine
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Very common for thos bolts to feel somwhat loose or snug, usually the only one being tight would be the black one. Remember, hold onto that cover going on and off, it can be tricky getting the idler shaft and dowels to line up just right if you havent done it before.
 
They use a loctite on that one vs none on the others. The others do need to be torqued down to spec though, although when taking them out once you break the initial torque thye remove very easy, giving them the not so tight feel although they are set to spec.

When drilling your holes with the template, take your time and let the drill do the work, try not to shove and push like crazy. Its a soft metal and will grap and twist as it exits and can cause some sore wrists, especially with the whole saw for the blower as the top edge will cut the very edge of the subframe if the holes are in the right place.

I could go on and on with tips the instructions dont have, but thats true for any kit out there. Have fun and take your time. Seems like your on the right track.
 
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