Before I toss this March 809 in the trash...

[BrewDrinkRepeat]

... can anyone offer any other advice or insight on how to get it to work consistently? I've tried every mounting orientation, every priming method, hot water, cold water (as a test; pumping cold water is useless to me) and the damn thing still loses its prime if the breeze changes direction.

As you can see from the photo, I currently have it in what is the most popular orientation (sideways, with the inlet on the bottom). I prime it by opening the first output valve (the one w/ no hose attached), and then I sssllllooowwwwlllyy open the top output valve to pump hot water up to the mash tun. Nine times out of ten it loses prime within five or six seconds, and the tenth time out of ten it loses prime with none of the output valves open at all.

I am mechanically inept, and I am perfectly willing to accept that I'm still doing something wrong here. If anyone can enlighten me I'd really appreciate it; otherwise I'm probably going to try a Chugger and give up on this thing. (BTW this is an older one with the smaller flow rate, if that makes any difference.)

Thanks in advance!

 

[beaksnbeer]

Try opening the in side then open the out side only 1/2 way

 

[BrewDrinkRepeat]

Thanks, done that already. I read that you need to open the output very slowly, and especially with hot water not to open it all the way. I barely get it cracked open before it cavitates, and sometimes it loses it before I open the output at all...

 

[day_trippr]

A few million March users out there ought to turn in their pumps, eh?

How 'bout a useful picture of the pump head? Can't see anything important in the one that's posted...

Cheers!

 

[amandabab]

it might be pumping more than those plastic disconnects can supply. what is the internal diameter on those?

 

[day_trippr]

I might be wrong (I blame the picture ) but it appears that the pump head is rotated to about the worst possible configuration possible - with the input at 12 o'clock. Try putting the input at 6 o'clock and see what happens.

As for the plethora of bits surrounding the pump, you might simplify that down to nothing but a straight shot of hose on the input side and a single valve on the output, and then lose all those plastic bits. If you can get a simple configuration to work, then you can experiment with all that extraneous stuff and see what breaks it...

Cheers!

 

[BrewDrinkRepeat]

A few million March users out there ought to turn in their pumps, eh?

No, not at all. To be clear, I'm only talking about this pump, which I just want to punch. My rig is very basic, I only (want to) use the pump to get hot water to the mash tun, which sits right above my HLT (total height from pump to mashtun is just shy of three feet, something this pump should be able to easily handle).

I might be wrong (I blame the picture ) but it appears that the pump head is rotated to about the worst possible configuration possible - with the input at 12 o'clock. Try putting the input at 6 o'clock and see what happens.

No, the input is at the bottom, and on the top side are two outputs -- one that leads nowhere (a "bleeder valve" of sorts for assuring the prime) and the top one leading to a ball valve that has my output hose connection. A better photo below...

what is the internal diameter on those?

They are the standard polysulfone QDs from More Beer, for 1/5" ID tubing, so the ID of the QD looks to be ~3/8", give or take.

As for the plethora of bits surrounding the pump, you might simplify that down to nothing but a straight shot of hose on the input side and a single valve on the output, and then lose all those plastic bits. If you can get a simple configuration to work, then you can experiment with all that extraneous stuff and see what breaks it...

Good idea, but not one I can do today -- I'm in the middle of a "more manual than I would like" brewday.

 

[Chrisl77]

What size nipple is on your kettle? I don't know if its just the pic but it looks like you have a bushing in that valve to reduce down to the nipple?

 

[day_trippr]

Restrictions on the input side are to be avoided, and it's best to maintain 1/2" ID on the input side at least. The pump instructions I received with my 815s said not to put an elbow directly on the pump input...

Cheers!

 

[brewingmeister]

Ditch the elbow and the valve on the input.

 

[amandabab]

3/8 is too small on the input side. I use 5/8 barbs with 1/2" Id.

Also if you must have an elbow right at the input side, use an elbow and a close nipple not that street-L. street L's are cast and have a small ID on the male thread end.

 

[mpcluever]

Ditch the elbow and the valve on the input.

Agreed. No need for a valve on the input as you should never be restricting the input and the valve on the kettle will stop the flow. I have an elbow on my input and it works fine. If mine won't work, I just open that sample/priming valve with the pump off until water flows out. Once I get water out that valve, it works every time without fail.

Edit: my elbow is a street and works fine.

 

[outside92129]

The CPC self sealing disconnect is causing me big worries. It may have a 3/8 input (which is another problem) but it's not a ball lock and the pin-shutoff mechanism will cause significant flow reduction. Note that morebeer says it's ideal for glycol, but no mention for beer/wort into a pump. I have some of these for cooling water, but i wouldn't use it for wort, you should use camlocks instead.

http://morebeer.com/products/cpc-female-12-mpt-shutoff-valve.html?site_id=9

 

[mdgagne]

Goal on the input side is to have as little restriction as possible. Ideally, this means nothing less than 1/2 inch ID between the source vessel and pump input. I have this with my pump and when I open my source (Mash tun) wort will flow from the tun through the 4 feet of tubing, through the pump, and most of the way through my output tubing (4 feet). I then turn on the pump and throttle back the flow with the valve on the pump output.

 

[mpcluever]

The CPC self sealing disconnect is causing me big worries. It may have a 3/8 input (which is another problem) but it's not a ball lock and the pin-shutoff mechanism will cause significant flow reduction.

Agreed. Those quick connects restrict a lot of flow, especially if they have the shutoff built in.

 

[BrewDrinkRepeat]

Good tips, thanks! I'll do a water test one night this week without the ball valve or elbow and will report back. (I don't recall reading to avoid elbows on the input, but I might have just missed that bit...)

The QDs have no internal shutoff, they are simple disconnects. I have plans to replace all of them throughout my system with camlocks in the coming months, but I have a few other more important brewery purchases to worry about first (a pH meter, and I think my Ranco is about to die as it keeps tossing up E2 errors if I don't keep it set to Celsius.).

 

[outside92129]

Just to humor us, can you try it without the QDs as well?

 

[jtejedor]

Man I have to admit when I read all the stories of people having a heck of a time keeping their march pumps primed I was a little hesitant to get one. Don't know if it makes much different but I got the new one Morebeer sells that is supposed to have more flow. I have never once had one single issue with losing prime. I have the stainless disconnects from morebeer. Very simple setup just the 1/2 silicone tubing going to the in with a pretty short run, valve on the output side and kind of a long run of tubing up to the wort chiller. I don't have a stand for it I just have it on the floor pumping away and never had one bit of trouble with it losing flow. If it is a flow issue I believe you can purchase the higher flow head from morebeer to basically upgrade your model to the high flow one. Probably cost you a lot less then buying a whole new pump.

 

[LordUlrich]

If you are only pumping out of your HLT I would connect the pump inlet directly to the ball valve on the HLT. No disconnects elbows or tubing. I do this and have tried to get my pump to cavitate and need to close my valve all the way to get it to cavitate.

 

[outside92129]

brewdrinkrepeat - Did you solve your pump issues?

 

[BrewingChemist]

if you still want to get rid of it, let me know! I'd give you money for it!

 

[BrewDrinkRepeat]

Hey all, sorry for the delay. Didn't have time to get out into the brewshed to work on this until last night. I was able to eliminate the elbow and the QD from the setup, but I had to leave the ball valve in as that was the only thing I had available to allow me to connect the hose to the pump. (Pics below.) So far, so good -- testing with ambient-temp water the pump never lost its prime or cavitated. Hopefully this continues with hot water (I have read that these issues can happen more easily with near-boiling water, not sure if that's true or not.)

Thanks everyone for your suggestions, and I do want to apologize about the thread title -- that was a 90F day brewday, super-high humidity, inside of a brewshed that topped 100 as soon as one burner was lit. I hate summer, I hate heat, I hate humidity... I was cranky and irritable and had already lost 5 gallons of fluid before I even started to mash. At some point I think adding insulation and drywall, and a window A/C unit to the shed is a must. If I want to keep brewing in the summer, that is.

 

[Foosier]

Just one thought to add. I was watching a buddy use his pump to move water from the HLT to his mash tun and he kept having priming issues. We kept adjusting the configuration of the lines, to no avail. Finally we realized the issue was the boiling water was bubbling air directly into his center mounted dip tube. This air would build up about every minute or so in the pump head and break the prime. We solved the issue by killing the burner while pumping.

Do you use a center mounted dip tube? If you do you might want to watch out for you dip tube picking up air from the boil.

 

[BrewDrinkRepeat]

Typically I start recirculating the hot water while the burner is on, to get the pump and tubing preheated to avoid losing too much temp. while pumping to the mash tun. Once I hit my strike temp, however, the burner is off and then I redirect the output to the mash tun. And through all of this I don't get to boiling temps, my strike temp is normally in the upper 160s to mid-170s depending on the batch and target mash temp.

 

[grathan]

I've always hated priming the march pump. Lately I just take the garden hose and shoot water back through all the lines and pump so they are full and then turn it on. instant prime.

 

[DRog00]

I've had my troubles with pumps in the past, but since I hard plumbed my setup, I have had zero problems. My pump is located about 12" below my dip tube, with the pump motor mounted up, head mounted down. I recirc back into the mash tun at the end of the mash, and additionally after I am done boiling for cooling (plate chiller whirlpool). I have noticed that when the wort is at boiling temps, there is some cavitation, however, it never stops pumping.

(mine is mounted like this, but this isn't my setup

)

How many feet of line do you have above the head of the pump?

BTW, cavitation is real. At boiling, the pump will basically pull a vacuum which causes near boiling wort to boil again, creating an air pocket.

 

[brew2dan2]

I have had some issues as well, and figured out that if I prime with the pump sideways, and ALL ball valves open, I can get prime once I see water in the outflow hose. I'm also super paranoid about cavitation, as it makes me feel like I'm breaking the pump. My setup has 3 ball valves, but the only one not fully open is the pump valve, monitoring the flow. FWIW, I recirc my mash in a blichmann 10 gal, where I think the dip tube is less than 1/2" ID - could be totally wrong - and don't have problems. Hope you get yours figured out soon!

 

[BrewDrinkRepeat]

The ball valve on my HLT is about 18" - 20" above the inlet of the pump (guesstimate, I never actually measured it but it's a good distance).

 

[day_trippr]

[...]FWIW, I recirc my mash in a blichmann 10 gal, where I think the dip tube is less than 1/2" ID - could be totally wrong - and don't have problems. [...]

fwiw, the stock Blichmann dip tubes are fabricated from 1/2" thin wall stainless tubing with an ID of 7/16"...

Cheers!

 

[WalterAtMarchPump]

Sorry I missed this thread...no sure how I didn't see it but going over the postings the members have hit all the bases with tubing/fitting size and orientation etc....the only thing I can add to this is for you to take the pump head apart and make sure that the Teflon thrust washer is still there...they do wear out over time. And if its gone then the impeller could be rubbing up against the housing and dragging...possibly de-coupling.
If the washer is gone shoot me a PM or email and i'll get one out to ya.