Page 1 of 2

Rotax 2 stroke pulse pump

Posted: Thu Jul 22, 2010 10:03 am
by Boet
On my inspection rounds, I often see Rotax pulse pumps not installed correctly. Underneath the pump is a very small hole thas must point downwards. This is a breather hole that gets rid of the 2 stroke oil that finds it`s way into the pump, via the pump action thru the crank case of the engine. If you install the pump vertically, over time it will start filling up with oil. up to the half-way mark. IE: Only HALF of your fuel pump will then be working properly. How do I know? I made the mistake, and learned the "exiting way" ! Now you do not have to make the same mistake. Learn from it. :wink:

Re: Rotax 2 stroke pulse pump

Posted: Thu Jul 22, 2010 11:00 am
by Grumpy
Your picture shows a horizontal installation. Is that correct?

Re: Rotax 2 stroke pulse pump

Posted: Thu Jul 22, 2010 12:18 pm
by Biggles
The pulse pipe is the one that comes into the centre of the housing and should be mounted in such a way that any oil that makes it too the pump should be able to flow back down the pipe to the engine. Mine is mounted correctly (horizontal) but lower than the engine so if it did get oil it would accumulate in the pipe (am I right?). I have taken this pipe off and found the pipe was clean. But on my list of things too do.

Re: Rotax 2 stroke pulse pump

Posted: Thu Jul 22, 2010 6:32 pm
by Boet
Grumpy, yes, horizontal is correct. Biggles, valid point. If it sits slightly higher than the pulse take-off point in the case, some of the oil will run back. It is a slight "oil mist" we are talking about here, so it will take some time to get serious. But then better safe than sorry. What? :wink:

Re: Rotax 2 stroke pulse pump

Posted: Fri Jul 23, 2010 9:50 am
by Grumpy
Boet, can/should one open and rinse out this oil in the pump at all? or better just leave well alone?

Re: Rotax 2 stroke pulse pump

Posted: Fri Jul 23, 2010 10:24 am
by Tobie
Very interesting, mine is installed horizontally and with the centre pipe on top. I have recently seen oil accumalating outside around this pipe and thought it may be due to a little leak from the oil reservoir nearby which I couldnt find. Maybe that centre fitting is seeping oil and is it ok if the pump is installed with the pipe on the top side or should it be underneath.

Re: Rotax 2 stroke pulse pump

Posted: Fri Jul 23, 2010 1:18 pm
by Boet
Tobie, the oil seep is normal. That is the oil that HAVE to seep, otherwise the pumping action will be impaired = loud silence. The copper elbow must face down. Look carefully, it has a very small hole in it. Grumpy, keep your grubby paws out of da thang. You will just bugger it up completely. :wink:

Re: Rotax 2 stroke pulse pump

Posted: Fri Jul 23, 2010 1:36 pm
by Grumpy
Boet wrote: Grumpy, keep your grubby paws out of da thang. You will just bugger it up completely. :wink:
Yo Yo Yo, Amper vloek ek noy jou moer, oubaas. (**) (**) See my pump installation. Nou Hoe nou?

Re: Rotax 2 stroke pulse pump

Posted: Sat Jul 24, 2010 5:23 pm
by Biggles
Grumpy, I would make an upside down L bracket that uses the same mounting pionts and then mount the pump horizonatlly on the bracket, so you are rotating the pump 90 degrees. So the pulse inlet is at the bottom and you won't have too mess with fuel lines iether.

Re: Rotax 2 stroke pulse pump

Posted: Sat Jul 24, 2010 5:26 pm
by Biggles
If you are going to pull a pump appart you might aswell get a sevice kit and replace all the goederkies while your at it (!!)

Re: Rotax 2 stroke pulse pump

Posted: Sat Jul 24, 2010 5:32 pm
by Boet
Ik heg gezeght jonge. Maak er van wat je wilde. :wink:

Re: Rotax 2 stroke pulse pump

Posted: Sun Jul 25, 2010 3:55 pm
by Grumpy
Boet wrote:Ik heg gezeght jonge. Maak er van wat je wilde. :wink:
Answer my question instead of confusing me with this garbage ## ## Aashlog !! (**) (^^) (^^)

Re: Rotax 2 stroke pulse pump

Posted: Mon Jul 26, 2010 10:20 pm
by Boet
Grumpy, turn the damn thing right way up. Make an aly bracket, using the same mounting point. Should not be too difficult? Refer to first post. ## ## ##

Re: Rotax 2 stroke pulse pump

Posted: Mon Jul 26, 2010 10:55 pm
by Oupa-G
Valuable info,also new to me but makes a lot of sense thanks Boet

Cheers Oupa-G

Re: Rotax 2 stroke pulse pump

Posted: Tue Jul 27, 2010 6:34 am
by Cloud Warrior
But then why does Solowings mount the pump vertically as standard? :?