Trap primer issues

charliechicago

Hello to all. I have an issue with a "water saving trap primer" in a house that is/was spilling water from the air ports that prevent siphoning. Originally they had a bad leak coming from the trap primer so they called someone over and he cleaned out, I think, the main drain. It helped a lot but it still leaked so he came again and did something. That helped more but it still was dripping a little from the ports. I came and took off the 1/2 male adapter on the bottom and found a lot of gunk but no blockage in the line going out to the trap. When I put it back, it didn't drip like before but when the cold water shut off, it splashed once, right out the ports and it wasn't doing this before. This trap is fed from the water going to fill a toilet. The only thing that changed is when I was working on the trap I closed the water to the toilet and then opened it again when I was done. When I meter down the water feeding the toilet then it works fine but the customer doesn't want that. I know that before I closed it, it was more open then I have it now that I metered it down but maybe not as much as when I opened it all the way after I cleaned it out before testing?
The trap primer feeds some sort of trap behind the wall that I can't access or see very well. One thing I noticed is that it only comes down out of the primer 2 inches before it turns and I saw in the instructions on a new trap primer that I have that there should be a minimal of 12 inches. This is an old house and its been there for a while. Its located in the beams in the basement. Any suggestions would be appreciated. Thank you, Michael.