Servicing and Rebuild of MSR Standard Fuel Pump

Fuel Pump Maintenance & Rebuild

Required materials: MSR Whisperlite Expedition Stove Service Kit

Parts: Assembled PumpWL pump_parts overview_01

Parts: Disassembled PumpWL pump_parts overview_02

Lubricate the pump cup

1)  Push plunger in halfway so that arrow 1 (printed on plunger shaft) is lined up with the plunger bushing

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2)  Twist the plunger counterclockwise (arrow 2) until you hear it click free

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3)  Pull out to remove the plunger (arrow 3)

4)  Remove pump cup and firmly press the new cup onto the plunger tip

5)  Rub MSR pump cup oil onto the pump cup

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6)  Reinsert the plunger by holding the plunger shaft and align the top of the plunger bushing with arrow 1 on the plunger shaft

7)  Align the plunger bushing legs with the locking holes in the pump body

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8)  Push the plunger and plunger bushing into the pump body until the legs snap into the locking holes

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Replace the fuel tube O-ring

1)  Remove the plunger (see above)

2)  Using the jet & cable tool, rotate the fuel tube bushing counterclockwise and remove

3)  Remove the fuel tube o-ring using a safety pen (or the end of the fuel line)

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4)  Replace the o-ring and fuel tube bushing, and re-assemble


Replace the control valve O-ring

1)  Using the jet & cable tool, loosten the control valve stop nut

WL pump_control valve_01

2)  Unscrew and remove the control valve

 

3)  Replace the o-ring, and re-assemble the control valve


Replace the pump seal

1)  Remove the pump seal

WL pump_pump seal_01

2)  Replace the pump seal. Ensure that the pump seal seats properly over the rim on the pump body. Use a small amount of the pump cup oil to help seat the seal.


Clean and replace the check valve

1)  Turn the check valve counterclockwise and remove the check valve assembly

2)  Clean the cavity and seal of any debris

3)  Replace the check valve assembly


Replace the fuel tube and filter

1)  Pull fuel tube and filter out of the pump body

2)  Push new fuel tube into place firmly

WL pump_fuel tube_04


Replace the fuel bottle O-ring

1)  Remove and replace fuel bottle O-ring if damaged or worn

WL pump_bottle cap_01


 

Servicing and Rebuild of MSR Whisperlite International (pre-2012)

Stove Maintenance & Rebuild

Required materials: MSR Whisperlite Expedition Stove Service Kit

1)  Unscrew the priming cup and remove the priming wick.

2)  Remove the fuel line from the mixer tube.

3)  Remove the fuel line from the stove leg. With a little maneuvering the line is easily removed from the stove leg, no force needed. Take care to not bend the generator tube.

4)  Unscrew the jet using the jet & cable tool, and remove the shaker needle. Take care to not bend the generator tube.

5)  Pull the cable out of the fuel line using the jet & cable tool.

WL rebuild_fuel line_07.jpg

6)  Reinsert the cable and slide it back and forth inside the fuel line using short strokes (do this about 20 times). Remove the cable when done. This step loosens and debris that may be inside the fuel line.

7)  With the cable, jet, and shaker needle removed, insert the end of the fuel line into the pump and fuel bottle.

8)  Pressurize the fuel bottle with 10-15 pumps.

9)  Open the control valve fully and flush 1-2oz of fuel through the fuel line into an appropriate container (such as a second fuel bottle).

10)  Fully reinsert the cable into the fuel line. There will be about 1/2 inch of cable remaining out the end of the fuel line. Set the fuel line asside.

11)  Slide the stove legs down off the mixer tube / burner head assembly.

WL rebuild_stove breakaway_01

12)  Dissasemble the burner. Unscrew the top screw and separate the mixer tube from the burner. The burner separates into 9 pieces. Keep the pieces in order to make assembly easier.

13)  Whipe down each piece to clean away any loose material. Careful not to bend.

14)  Reassemble the burner making sure that the pieces go back together in the correct patern (Alternate crimped rings and flat rings to get a coregated structure). Snug down, but don’t fully tighten the screw at this point. The mixer tube will be oriented to the correct position when the fuel line is re-connected.

WL rebuild_burner_02

15)  Reposition the stove legs onto the mixer tube. ORDER MATTERS! See photo for correct assembly to have a level stove. Note the angle of the stove legs (leg 1 angles down, leg 2 is strait, leg 3 angles up).

WL rebuild_stove legs_01.jpg

16)  Replace the shaker needle and jet. Be sure to use the correct jet for your stove. The type is indicated on the side of the jet. For my stove, the jet type is IG or K.

WL rebuild_jet_03.jpg

17)  Feed the fuel line through the leg 2 and re-insert the generator tube into the burner and the jet into the mixing tube (reverse of step 3).

18)  Seat the fuel line / burner assembly into the correct position and tighten the burner screw.

19)  Replace the priming wick and priming cup.

20)  Fire up the stove and keep on cooking!

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Winter at Ottaway Lakes

Day 1: Happy Isles to Merced Meadow (March 26, 2014)

This was my third snowshoing trip up Happy Isles into the Yosemite high country. The climb is always a challenge, and this year it was wet and snowy. NOAA had issued a winter weather advisory for the area we were heading into, calling for winds above 30 mph and significant snowfall above 6,000 ft.

IMG_6813Flurries were already falling as we packed up our gear and started up the trail. When we reached the bottom of Nevada Falls it was snowing steadily. By the time we crossed the top of the falls, the snow was falling fast and the wind was begining to pick up. As we continued up the ridge above the falls, we passed a group of day hikers heading back to the valley. It was clear the weather had caught them by surprise.

My legs were feeling the load of a full pack and 5,000 ft of climbing out of the valley as we crested the ridge. The snow was now about 6 inches deep as we made our way past Mt Starr King.

We made camp near Merced Meadow. It was snowing hard as we set up camp and retrieted into our tents. The snow turned to rain as the sun set.

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Crossing the top of Nevada Falls

Day 2: Merced Meadow to Lower Merced Pass Lake (March 27, 2014)

I woke up to the sound of an owl hooting near by. Snow continued to fall last night until sometime after I fell asleep. The air was chilly and the sky blue when I climbed out of the tent.

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We hit the trail around 9:00 AM. The trail was burried under about 8 inches of snow as we made our way through long stretches of redwoods, sagging under the weight of fresh IMG_6891snowfall. After a few miles, the trail begain to climb towards Merced Pass Lake. As we climbed, the snow became deeper until we were setting new tracks into knee deep powder.

Clouds began to cover the sky as we came up to Lower Merced Pass Lake. The lake was frozen over and covered in a thick layer of snow. We made camp at the lake edge.

As the sun began to set, I cleaned up from dinner and climbed into the tent. The air was still and the temperature had dropped significantly as I climbed into my sleeping bag for the night. The sound of sleet falling on the tent started up as I drifted off to sleep.

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Camp at Lower Merced Pass Lake

Day 3: Lower Merced Pass Lake to Lower Ottoway Lake (March 28, 2016)

The night was cold.

When the sun started to shine, I could see that the inside of the tent was covered in frost. It looked like the inside of a freezer. Getting up was a challenge. Every move knocked frost from the sides of the tent down on me. I felt like it was snowing inside the tent!

Outside, the sky was clear and the air brisk. My boots were icy and stiff, but warmed up quick as I moved around making breakfast and coffee.

IMG_6955We started up the trail putting first tracks in the deep powdery snow as we made our way up to Lower Ottoway Lake. The day warmed up quickly, and the snow became soft and heavy under our feet. Along the way we got a view back towards the valley. The south face of Half Dome looked like just another distant rolling hill of the High Sierra.

Ottoway Lake was covered in snow with an outlet stream flowing slowly down towards the valley. At the edge of the lake we stood at the base of three large peaks that towered above (Red Peak, Ottoway Peak, and Merced Peak). The view was fantastic!

We hung out at the lake for a while, eating lunch before heading back to camp at Merced Lake. It was a warm, quick hike back.

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Lower Ottoway Lake

Day 4: Lower Merced Pass Lake to Happy Isles (March 29, 2016)

IMG_7018It was another cold night. The sky was cloudy as we packed up camp and made our way back to the car. The hike back was down hill and fast. We quickly decended out of the snow, and were back on snow free trail as we made our way past Mt Starr King towards Nevada Falls. All the snow that had fallen on our first day out had melted in the last couple days.

Back at the car, the clouds grew thicker and a light rain began to fall as we loaded up and headed back home.


See more photos from this trip on Flickr!

Mosquitoes and Thunder Storms

Day 2: Vernon Lake to Tiltill Valley (June 9, 2013)

Morning at Vernon LakeI woke up with the sun again this morning to a canopy of mosquitoes staring down at me from the other side of my tent’s mesh. The morning quickly warmed up as I lay there looking up at the pests until it was too warm for me to stay in the safety of my tent. It wasn’t long after climbing out of the tent before I felt the first bite.

I gathered up my cooking supplies and made my way to a nearby sunny rock overlooking the lake. Direct sun made for a hot start to the day, but it kept the mosquitoes down to a manageable level.

After breakfast we hit the trail. It was 9:30AM and the temperature was already approaching 90°F as we made our way up an exposed granite face towards the ridge. This was the last major climb of the trip.

Looking down at Vernon Lake

Looking down at Vernon Lake

There's a trail through there somewhere...

There’s a trail through there somewhere…

Crossing the ridge brought us into another stretch of forest recovering from fire. The chaparral was above head level and the trail was in serious need of maintenance. The hiking turned into bushwhacking. As we descended through the chaparral we were giving some beautiful views of Hetch Hetchy Reservoir Valley.

We descended down a long series of switchbacks into Tiltill Valley. We stopped here for lunch and a water refill. It was about 1PM and I had already burned through most of my 3.5L supply. I also took the time to rinse off the thick layer of dust that coated my face. The water was cold and refreshing.

As we packed up from lunch we heard a faint rumble of thunder in the distance. After a few more rumbles we determined that the storm was heading in our direction. The map showed the trail moving into more exposed terrain, so we decided to make camp here at Tiltill Creek rather than risk being caught on open granite.

Tiltill CreekWith my tent up, I climbed in just as the first rain drops began to fall. It was quite warm in the tent, but with thunder cracking over head, I thought we had made the right choice.

The storm was louder than wet. The wind picked up as the thunder carried on and the drizzle stayed heavy enough to keep us in the tents. This continued for a couple hours, but by 5:30PM the wind died down and the sky cleared up just in time for a spectacular sunset!

The mosquitoes made it another early night. I was hopeful that they would stay in the high country as we descend to the reservoir the next day.

Photo Credit: Paul

Sunset at Tiltill Valley (Photo Credit: Paul)

Day 3: Tiltill Valley to Hetch Hetchy Backpacker Camp (June 10, 2013)

Mosquito TerritoryThe sun returned early the next morning bringing with it mosquitoes and humidity.  We took care of breakfast and packing up camp quickly. This was probably the worst morning of mosquitoes. The trail took us strait across the valley through tall grass, marshy ground, and a thick cloud of mosquitoes that were un-phased by the DEET. We moved quickly!

The mosquitoes hassled us until we got out of the valley and well over the ridge onto more exposed ground. It was a relief to get a break from swatting and slapping at the little winged beasts. As we worked our way down the switchbacks towards Rancheria Falls we passed a large group of hikers heading up to Tiltill Valley to do some trail maintenance and invasive species removal. The mosquitoes were certainly going to give them a hard time…

Rancheria Falls

Rancheria Falls

Rancheria Falls was a tent city. This must have been the staging area for the trail crew. From the falls, the trail moves above the shore of the reservoir several miles before returning to the dam. This was probably the most scenic stretch of the trip with many great views of the valley and crosses a couple waterfalls. It was a great stretch to finish the trip on!

Hetch Hetchy Reservoir

Hetch Hetchy Panorama

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Don’t miss the first part of this trip!

Find more photos on Flickr!

Hot Hot Hetch Hetchy

We rolled into Hetch Hetchy Friday evening just before the gates closed at 9PM. After grabbing our permit, we made our way to the backpacker camp. It was warm and the sky was clear as we set up camp for the night. The weather for the weekend was supposed to be hot, so we were planning on getting an early start to beat the heat.

Day 1: Backpacker Camp to Lake Vernon (June 8, 2013)

Crossing O'Shaughnessy Dam

Crossing O’Shaughnessy Dam

I woke up with the sun at about 5:30AM. Hugues and Paul arose shortly after and we hit the trail by 7AM in an effort to climb out of the reservoir valley before it got too hot.

The wind was blowing hard across the reservoir as we crossed the dam and started up and out of the valley at 7:30AM. The temperature had already reached 80°F!

The climb out of the valley was steep and hot, but we made it to Beehive by 10AM. From here we took a short detour to Laurel Lake for lunch and a swim. At this point the temperature had reached 95°F. I was the first one in the lake and the water felt amazing!

Laurel Lake

Laurel Lake

After a swim and some lunch, we continued towards Lake Vernon. Much of the trail was through forest recovering from a wild fire several years ago. The recovering forest had a fair Granit slabs towards lake vernonamount of standing water to support enough mosquitoes to keep us moving at a quick pace.

As we approached the hottest part of the day we cleared what remained of the forest and made our way across granite slab with sparse tree cover. The sun was beating down hard, but we were getting close to the lake where we would set up camp for the night.

Once at the lake, it wasn’t long before we found a nice campground with a fire ring in a small cluster of trees. We dropped the packs and headed for the lake. Vernon was a bit colder than Laurel Lake, but after hiking in 95°F weather it was just the refreshing swim we needed!

Lake Vernon

Lake Vernon

Relaxing by Lake Vernon (Photo Credit: Paul)

Relaxing by Lake Vernon (Photo Credit: Paul)

Backcountry PizzaAfter a swim and some lake side relaxation, I made my way back to camp to set up my tent and take a much needed nap.

It was still early when I started preparing dinner, but I was baking pizza so I needed the extra time. This was the first trip in CA that I was able to build a twiggy fire on my Fry-Bake because of the ever-present fire restrictions, so I took advantage of it! After baking to perfection, I chowed down on a pizza in the backcountry!

As the daylight faded, we managed to clean up from dinner just before the mosquitoes attacked… The sun had just set, the wind died down and the skeeters came out in full force! Even my 100% DEET didn’t seem to phase them, so we retreated to the tents for the night.

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Find more photos from this trip on Flickr!

Lake Vernon Camp

Lake Vernon Camp

Tenaya Lake and Beyond!

Day 3: Tenaya Lake & Snow Creek Cabin (March 29, 2013)

Frosty TentsThe morning was very cold with a thick layer of frost covering the tents, so we didn’t waste time packing up and getting on our way. Once we got out of the small valley we camped in the temperature warmed up significantly. The sun was out and a few clouds floated overhead.

The four miles between camp and Tenaya Lake were mostly down hill and went by quickly. We arrived at Tenaya about noon. The lake was frozen over with a layer of blue ice. We could see ski tracks crisscrossing the surface.

Ice covered Tenaya Lake

Ice covered Tenaya Lake

From Tenaya we were going to follow Tioga Pass towards Snow Creek cabin. Before we could continue down the road, we first had to cross the wide outlet of Tenaya Lake and there was no bridge… We found a section that was fairly shallow and would let us cross to a snow free patch of river bank.

Tenaya outlet crossing

Stepping out of the boots onto the cold snow was accompanied by a few yelps of shock. The snow bank held us about a foot and a half above the water and the first step down was taken with visions of the snow breaking away under foot flashing through my head. The water felt surprisingly warm compared to the snow moments before, but after a few steps the cold crept in and my toes began to tingle, each step getting a little shakier as the cold water numbed my feet. Back on the dry river bank we stopped for lunch and let our feet dry and warm up in the sun. The air temperature was quite pleasant.

Making our way down Tioga Pass

Making our way down Tioga Pass

After lunch we started our way down Tioga Pass towards the Tuolumne Meadows Trail. We were getting the full force of the afternoon sun as we made our way down the road. The sun had made the snow quite soft which made for slow going with the snow shoes. Hiking was hot and slow, but offered some spectacular views of Clouds Rest.

Clouds Rest's granite face

Clouds Rest’s granite face from Tioga Pass

Once we reached Tuolumne Meadows Trail, we left the road and started descending towards Snow Creek Cabin. The trail was marked by license plates attached to trees high above snow line. We lost the trail markers as we descended from the ridge where we found the stream that the cabin was supposed to be by.

The exact location of the cabin is not clearly marked on maps and does not appear on the Tom Harrison map that I had. So we were following GPS coordinates that we found online along with a vague description of the location of the cabin. We found the intersection of the Tenaya Lake and Tuolumne Meadows trails. From there is was a matter of fanning out and playing a game of hide-and-seek with a cabin. We wondered the woods for 15 to 20 minutes before I spotted the cabin peaking out between the trees!

Snow Creek Cabin

Snow Creek Cabin

The cabin was far greater than any of us imagined! It was two floors complete with a wood stove in the living area, a kitchen (no plumbing or electricity, but it did have a propane stove!), three bedrooms, outhouse, and an ample supply of dry wood! There were cards, board games, books, dishes, and even a guitar! We were the only ones there, so we got a fire going and enjoyed a warm evening in a backcountry cabin.

Snow Creek Cabin - Living Area

Living area

Kitchen

Kitchen

Warming up by the fire

Warming up by the fire

Day 4: Descending Snow Creek Trail (March 30, 2013)

Bridge over Snow Creek

The next morning we closed up the cabin and started our way down Snow Creek Trail to the valley floor. This trail descended gradually for a couple of miles before we started down the 108 switchbacks to the valley floor. The descent was steep and offered great views of the valley below, but I was very glad we didn’t climb this route our first day out.

It wasn’t long before we were back at the car and on the road back to the Bay Area. The end of amazing trips is always sad, but it was a great feeling to have conquered Clouds Rest in the snow!

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Don’t miss out on the first half of this trip!

For more photos check out the album on Flickr!

Descending Snow Creek

Descending Snow Creek

Clouds Rest 2.0

Having been defeated by snow conditions the previous year, we were back in Yosemite to attempt a summit of Clouds Rest in the snow. The goal once again, was to loop the valley starting at Happy Isles trailhead and climbing up-and-over Clouds Rest on our way to Tenaya Lake, returning via Tioga Pass and the Snow Creek trail to complete the loop.

Day 1: Happy Isles to JMT Cutoff (March 27, 2013)

Vernal Falls as seen from the Mist trail

Vernal Falls as seen from the Mist trail

This winter had been warmer and dryer than the previous. This was evident as we made our way up the Mist trail towards Little Yosemite Valley (LYV). Most years, this trail is still closed in March due to icy trail conditions. Not a problem this year.

Using the Mist trail cut about 1.5 miles off the distance to LYV where we had camped the year before. This year however, we continued a short ways past to where the John Muir Trail split from the Clouds Rest summit trail.

We made camp near this junction. The ground was mostly free of snow, and there was a stream flowing nearby for water. It was about 4:30PM as we made camp and it began to rain.

The next day we would be attempting the summit of Clouds Rest!

Day 2: Clouds Rest Summit Day (March 28, 2013)

The morning was cool, and the tents damp from the nights rain. We didn’t waste much time breaking down camp as we wanted to give ourselves plenty of time to summit Clouds Rest.

We hit the trail at 9:00AM. The sky was partly cloudy. It wasn’t until after the main switchbacks that we needed to put on snowshoes (The previous year we were in snowshoes starting from LYV).

Climbing Clouds Rest

The condition of the snow was very good as we worked our way towards the summit. The weather was on our side as we made the final steep push that had turned us back the year before. Where there had been a sheet of ice, there was now dry steps leading us to the summit.

We made it!

Winter Summit - Clouds Rest

On the summit of Clouds Rest (9,931 ft)

On the summit just after noon, we could see for miles. The sun was out, but dark clouds were hanging in the distance.

With another summit under our belts, we turned our attention to getting down before more weather moved in. We made our way off the other side of the summit, down the knife edge.

Paul making his way off the summit with Tenaya Lake in the distance

Paul making his way off the summit with Tenaya Lake in the distance

Camp night 2 (Photo Credit: Paul)

Camp night 2 (Photo Credit: Paul)

From the summit, we made our way into the neighboring valley for camp. The valley was deep with snow, and it took some time to build a sturdy platform for the tent. We were once again camping near a stream, though this one was buried under about 4 feet of snow.

The clouds moved in for night two of weather and it began snowing. As daylight faded, large, heavy snow flakes began falling and we retreated to the tents.

It had been a long day of snowshoeing, but the satisfaction of completing the summit was immense! The next day we would be making our way to Tenaya lake then onward to Snow Creek Cabin.

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Continue with the second half of this trip HERE!

Check out more photos on Flickr!