Having bother with my Doda pump again . Don’t use it that much but sometimes I prime it then pto on & away it goes but sometimes like today it will prime but pto on it just lets go of liquid . The liquid is foamed up when I take pipe off indicating drawing air but I just can’t see where . Is my mechanical seal buggered? It does leak a bit
Doda not pumping
- Thread starter valtraman
- Start date
- Location
- South West
We had a doda give no end of issues and the parts for them now are mighty expensive.
Ended up with a Bauer, seems like twice as much metal and very good output, more than the doda!
Ended up with a Bauer, seems like twice as much metal and very good output, more than the doda!
- Location
- South West
Alright throw another mechanical seal in it and see what happens. You’ve answered your own question in your OP….Well that was a great help cheers
- Location
- South West
Prime it up and turn the tractor off dead. If you can hear it hissing (air leak) as it’s running back down in to the lagoon then the mechanical seal is gone, the froth will just be where the impeller was spinning round ‘whipping’ up and slurry left there after she lost prime. The only other thing it could be is hole in your suction pipe. Do same as above, prime it up and listen, trace back any holes…
mechanical seal is relatively simple; just need to take everything off to get to it so if your impeller or chopper etc is marginal it’s probably the right time to just change it while it’s off…
mechanical seal is relatively simple; just need to take everything off to get to it so if your impeller or chopper etc is marginal it’s probably the right time to just change it while it’s off…
Prime it up close handle then switch off? There’s no other hydraulic valves or anything on it. Suction hose is new
- Location
- South West
Yeah prime it up so it’s ready to go, close the valve and turn everything off and see what you can hear. If you can hear air by the mechanical seal it’s leaking there; have a listen to the Bauer couplings too… if you can hear any air there’s potential that’s the issue.
Worth doing that before spunking 350 on a mechanical seal and it being a Bauer leaking…
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- Location
- South West
Done that before just to keep us going!Or wedge a glove under the closing ring for an extra seasons use out of that rubber
Change both the O rings,that’s the 6” one for the suction hose and the 4” one for the primer pot. Check the fitting on your suction hose is actually tight in the hose.
Doda are one of the cheapest pumps to run,most only give bother from neglect,miss use or objects that shouldn’t be in slurry.
Doda are one of the cheapest pumps to run,most only give bother from neglect,miss use or objects that shouldn’t be in slurry.
Which seal are you referring to? The mechanical seal or the O rings?
Is your lay flat that clamps on the pump tight with no movement?
- Location
- South West
If you can hear air leaking around the shaft area it’s nearly certainly the mechanical seal then. But for the sake of an extra few quid I’d do all the seals/gaskets on the ‘slurry’ end of the shaft being that you’d be getting that far to do the mechanical seal anyway. A doda mechanical seal is inherently easy to do, aslong as you’ve got heat and a good set of pullers you’d have it changed on your own in a couple hours..
Seals on lay flat are good , nice & tight clamped up . Air is sucking from mechanical seal area . I’m stripping into it to get impeller off to see seal
- Location
- South West
Might of already been asked but how full (or empty) is the lagoon?
sounds like you’ve found the issue being able to hear an air leak around the seal area but if your lagoon is particularly deep it may struggle to pull it that far up the bank. I’ve had it in the past where you can prime in the morning but can’t in the evening once you’ve nearly emptied it, when it’s like that we don’t turn it off and once it is going return it to the pit when changing fields etc so not to loose prime
It’s only a 6ft draw , primes up quick but must be drawing that much air it just lets go off it . Previous contractors never had an issue . Am finding gritty bits & few wee stones in pump so thinking that won’t be great for the pump
- Location
- South West
It should draw up to about 4 meters before it refuses so you’d be alright there.
stones/grit won’t be great for the pump but that’s more veins and outer case that will wear more than the mech seal.
we found mechanical seals go sometimes for no apparent reason and other times cling on in there even with a length of string wrapped round the back round the shaft, it’s one of them. As the mechanical seal is only a few hundred quid I’d throw new seals, gaskets and mechanical seal on it and see what happens myself, I’d put money on it sorting it…no point just doing the mechanical seal when the other seals and gaskets are already off and cost pence in comparison, if you’ve got that far may as well do a proper job of it