MSR Whisperlite Universal -- Pump Compatibility Problems

MSR has generally* made all of their stoves compatible with all generations of MSR fuel pumps. Any MSR stove could use any generation of standard pump, and any generation of standard pump could be used with any stove. It appears that MSR has broken with that custom with the new Whisperlite Universal.

Just for fun, I thought I'd try an older pump with the Whisperlite Universal. Much to my surprise, the fuel line would not go into the pump.


Do you see the problem? The aluminum block on the fuel line of the Whisperlite Universal is too wide to clear the red plastic portion of the pump seen to the right. In fact, if you look closely, you can see that I've chipped the red plastic.


Take a look at the below photo.

The fuel line on top is from a Whisperlite Internationale. The fuel line on the bottom is from the Whisperlite Universal. Notice how the Internationale's aluminum block is asymmetric. There is a good deal less aluminum on the side opposite the catch arm. The narrowness of the block on the side opposite the catch arm allows the fuel line to clear the red plastic portion of the pump shown in the earlier photos. Note that there's even a hair of clearance.


So now what? I suppose the real question is: "Did MSR do this by decision or by default?" In other words is MSR deliberately making their new stove so that it will not work with prior versions of their fuel pump or did it just end up that way? It seems odd that they would not support backward compatibility with their pumps. I think that I will write to MSR and ask if they're aware that their new stove can not be used with prior versions of their fuel pump. Comments?

HJ

*The Dragonfly being the exception.

 

Maybe so it does not work with the clone pumps from China but more likely that pump is not safe and is costing MSR too much in bad press and returns having it in the market.

 

The question also has to be asked Does the international fit the universal pump?
Can bet that in the near future only the universal pump will be available.
This is a good way to sell more stoves just like throwing away all the spare parts 5 years after a car was manufactured. I drive 2 20+ year old cars We wont quote the age of some of my stoves

 

It looks to me like the end of the tube is a bit longer on the old style hose and it may not fit in the universal pump.

If so, that too bad. Does not bode well for replacing pumps in the future.

 

There isn't a "Whisperlite Universal pump". In other words, there is no pump specifically made for the Whisperlite Universal (WLU). The WLU uses the current generation of the standard MSR pump, i.e. the "Duraseal" pump. The Duraseal pump is definitely "portable" between all of MSR's current stoves (except the Dragonfly of course).

What I'm noting is that the WLU won't work with previous versions of the standard pump. The WLU definitely does not have a stove-specific pump the way the Dragonfly does.

HJ

 

Yes, the Internationale does fit into the current generation standard pump.

The Whisperlite Universal isn't introducing anything new in the pump department. The current generation of the standard MSR pump, the Duraseal pump, came out about 4 or 5 years ago. The Whisperlite Universal just makes use of what MSR already had available.

HJ

 

OK, sorry.

May MSR just figures all their old pumps are crap, so why worry.

 

Just use an Omnifuel pump then, and you're all set.









HJ

 

I have tried the Whisperlite Universal's fuel adapter with old red & black pump, a gray & black pump, and a yellow pump. It does not work with any of the older pumps. I don't have one of the original white pumps, or I'd try it with that as well.

HJ

 

Hey, HJ, obviously the older MSR stoves had the cleaning wire sticking out like a sore thumb. Also notice that the new Universal version's hose looked slightly smaller and that the hose will not kink since the connector just turns without putting strain on the hose itself? As Steve of MSR puts it, its been redisigned so perhaps backward compatibility was not considered.

Ron

 

I wonder if they have a reason to not want people to flip the old pumps to release pressure? I do it all the time and don't know a reason but there might be one?

 

Heya HJ
I'm very intrigued with the notion that you can simply use the Universal with an Omnifuel pump. It occurs to me that you could also use the Universal as you've shown here with one of the replacement pumps for the Chinese TK800 stove. The TK800 pumps go for about $25 with shipping included and are really pretty well made. They have the Lindal valve connector (I hope that is the right term), so they should screw right on to the Universals threaded connector.

Curiously I have to report that at the OSG, MSR rep Steve spied my TK800 pump floating about in my backpack stove box and was really interested in it. I wonder if wheels were turning in his head along these same lines?

Here's a link to a post I made on the pump when it was called the S9:
https://classiccampstoves.com/posts/126169

Thanks for these pictures and thoughts on the WLU!
Cheers,
Gary

 

Ron,

Everything you're saying is true about the new Whisperlite Universal, but the only thing that prevents backward compatibility is about 0.5mm worth of thickness on the aluminum block on the fuel line.
Old pump with old aluminum block:


Old pump with new aluminum block:


See that little "lip" on the edge of the aluminum block? File off about 0.5mm of that lip and you've got backwards compatibility. I wonder if it's something they overlooked. I wrote an email to what I think is Steve's address and let him know. We'll see if he replies.

HJ

 

I can think of no reason not to flip the pump either on the old Whisperlites or the new Whisperlite Universal. The flip stop is so much better. Other companies specifically call for a flip stop and even go so far as to print ON and OFF on the appropriate sides of the pump. It beats me why MSR doesn't join the crowd especially with the Whisperlite Universal which freely rotates at the connector to the fuel adapter. It's so nice not to have gasoline spray all over your hands when you unscrew the pump.

HJ

 

Hi, Gary,

It just seemed natural to try an Omnifuel pump with the Whisperlite Universal. The Universal has a standard 7/16ths UNEF threaded connector, so it should mate with any other device with the same connector. It worked. In fact it worked really well. I think the stove was actually easier to run on liquid fuel with the gas adapter than with the standard MSR pump. The gas adapter has a very fine "touch" to it. I was able to get a very low boil with liquid fuel.

And that was on kerosene! I think the WLU is the best liquid fueled valve-at-the-bottle simmering stove to come out of MSR in at least twenty years. The only thing that simmers better is a valve-at-the-burner stove like the Dragonfly. I'm truly impressed with the WLU.

I've already sent the stove back to MSR, so I won't be testing any other pumps. I definitely would have liked to have tested it with a Brunton All Fuel or the like.

Usually a reviewer gets to keep the stove, but in this case prototypes are in short supply, and I had to agree to return the stove to MSR. Dang! This one would have been a keeper.

The other thing I'd like to have done is longevity testing, particularly with kero. It's all well and fine to boil maybe 10 liters of water with kero over a week and a half. But that's not really a durability test. I'd like to have done a few boils every couple of days for 6 months. Then I'd know if the WLU is truly reliable on kero. I will say though, for the kero testing that I was able to do, the stove performed very well.

HJ

 

Speaking of simmering, here's what I think is going on.

Take a look at this photo.

That's the WLU on the left and the WLI on the right. Now, look at the generators. The WLI's is straight up and down in its orientation. Compare that to the WLU's. The WLU's sort of curls over toward the lip of the burner "pan" (burner bell?).

Now look at this photo. I've just started a burn here, and the stove is still warming up.

Do you see how it's already glowing red under the generator? The geometry of the pre-heat loop creates a pocket, a pocket that traps heat. I think this heat pocket allows the stove to trap enough heat that it can continue to vaporize fuel even at a lower flame. That's my surmise anyway.

Whether I'm right or not, it works. The current Whisperlite Classic and Whisperlite Internationale are no where near as good at simmering.

HJ

 

Flame shots:

High flame.


Medium flame.


On the current Whisperlite stoves on the market, the photo marked "medium flame" is about as low as you can go.

Now look at what the WLU can do.
Low flame.


That's pretty darn good for a valve-at-the-bottle stove. That flame is reminiscent of the MSR stoves of old, the pre-Shaker Jet stoves.

Like I say, I haven't seen anything this good out of MSR in terms of flame control in about 20 years.

HJ

 

Looks like a bit of short work with a file or Dremel and you're in business, no? Other than the on pump/connector valve, I don't really see what difference a pump assembly would make if the pressures are equal. I know that during startup on some(Coleman) there is an air fuel mix going on, but once it's warmed up and back pressure from vaporization is occurring, shouldn't all things be equal? I'm not a fan of plastic pump rods and have thus far stayed away from MSR for that reason alone. My original Nova pump is built like a tank. I was going to convert ALL my remote bottle stoves to work with it until I got the price for the CEJN connectors. I haven't given up on it, but am waiting for a truckload of those connectors to roll over in front of my house. I agree that flip stop is where it's at. Purging the fuel line is a must in my book. Especially with kero.

I think your right on the money with the generator geometry HJ.

Mike

 

They wouldn't let you keep it because they know you're gonna buy one. Cheap bastages! LOL

Mike

 

I recall Prescall mentioned the lack of wow factor on one of the wlu threads, I agree. I had not realised that your stove was a prototype. Is it possible the legs won't be quite so "plain Jane" looking on the production stoves.