Gast 1550 won't turn

[mudr]

I looked and could not find any answers in old threads. I have a dry vane 1550 that I got up and running this year. It took some tweaking but finally got my releaser working. Everything worked for one day and I went put and found the pump off (out of gas) but also the pump would not turn.

I assumed bearing and pulled it open, but the bearing is fine, and also everything spins as soon as I get pressure of the side/end cap. However, it looked like I got some moisture into the pump (moisture trap had maybe a cup of sap in it when I found it, not a lot). The vanes were gummy. I cleaned things the best I could with isopropyl and put it back together. As soon as I tighten down the bolts, it binds up and won't turn. As soon as I back off the screws 1/4 turn, Things spin.

Any suggestions? Need a better cleaning? I didn't get in and clean the inside of the other "end cap", cam that be gummed and cause the problem?

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[Haynes Forest Products]

Mudr I have played with the same problem and found that 2 thing can cause it. There is the problem with the side plate alignment I ended up pulling the role pin so the plate could move slightly.

Now the side lash nut the one with the 4 spanner holes is what caused me the most trouble. the slightest over tightening of this nut will cause the pump to bind up and stall the motor. Yes I could spin it by hand but as soon as the motor kicked in it stalled tripping the breaker.

[MT Pockets Producer]

Did you have the pump apart to clean to prior to using it this season and if so were there any shims between the face plate and body? They look like a gasket and are made of Mylar. Gast sells them and they are color coded based on thickness. Very few thousanths thick. I had to put one on one of our pumps and made it out of Mylar window film I had laying around. That was three years ago and it has worked fine. It may help with the binding. If memory serves me correctly it was about .003 thick.

[mudr]

I tore down now to clean (think I didn't do good enough job though). Shim was there and is back in


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[Haynes Forest Products]

Mudr you started by saying you got the pump up and running. Was it working properly before cleaning. I say back the round threaded nut out a smidge.

[mudr]

It was working fine. Then it stopped turning, and then I pulled it apart. I do not think is a situation where I "fixed it till it broke", as it was broke before I did my first attempt at cleaning.

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[MT Pockets Producer]

After thinking a bit I do recall having a similar issue on our second 1550. I ended up putting a block of wood on the end of the shaft and giving it a wack with a hammer and it moved things just enough to free it up. I read in previous threads that others had to do that as well. Ours do not have the lash nuts the Haynes mentioned.

[mudr]

Good to hear another suggestion.

I do not have the same nuts as Haynes either (I think) but will check tonight.

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[Haynes Forest Products]

MT pockets does have a good point. I have had them give me fits after re assembly after rebuilding. Now the lash collar is small with 4 holes around it so it doesn't stand out. OH and one side is metal to metal and the other has the colored Mylar shim its not a gasket. :mad:

[MT Pockets Producer]

Any luck with your pump mudr?