Cafelat Robot Seal Failure?

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EbenBruyns

#1: Post by EbenBruyns »

I've been using my Robot everyday for about a year now, 2 shots a day with the occasional shots for friends. In the last week I've had it leak out the top of the seal twice. The first time I put it down to over filling, but this morning I'm certain it wasn't over filled.

It leaked the first time towards the end of the shot and it "popped" the seal. Today it "popped" the seal as soon as I released the levers at the end of the shot. I heard a popping sound.

The seal looks fine to me when I inspect it visually. I take it off about every 6-8 weeks to give it a clean. I've never re-lubed it and I'm wondering if it might need some lube?

Is there some general guidelines around this? I thought I might have to replace it, but since it looks fine and most people seem to get a much longer life out of their seals than a year, I thought I'd ask to see if what the latest learnings are around robot seals.

Jonk

#2: Post by Jonk »

There are a few threads about this. Some have needed to replace the gasket yearly, but many of us have gotten more use from our seals. It might look fine but probably different from a new one. Just buy a few and replace when needed, the new ones feel smoother to use so you'll get your money's worth.

EbenBruyns (original poster)

#3: Post by EbenBruyns (original poster) »

I have a few spares (when you live on a boat you learn to stock up on spares). I compared it to a new one and it's definitely stretched compared to the new one. I've replaced it and lubed it so I'll see how that goes. I've kept the old one just in case it wasn't the seal. I'm struggling to understand how a stretched seal would behave the way it does, but I guess there's a difference there and the new seal fits much, much tighter.

Ken5
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#4: Post by Ken5 »

Same thing happened to me after almost a year and a half. Water coming out above and a popping sound feeling. My gasket was also larger than the replacement. When I put the new one on the handles 'seemed to lift without any resistance, seemed different than with the one I took off, but I did not feel like putting the old one back on to see. Can only guess that the larger size may have been the reason.

The popping sound I am 'guessing' that the gasket tip may have bent up during the shot, creating the leak, and the sound when lifting was when it bound enough to the basket to make it snap back to normal position? Just a guess.

Ken

I watched the movie adrift the other night. I have a lot of respect for people that sail the world.

EbenBruyns (original poster)

#5: Post by EbenBruyns (original poster) »

The seal also felt softer. I'm guessing that because it's more pliable it was able to bend in ways that it shouldn't. I'll report back in a few days. If this solves it I guess I'll be ordering a few more spare seals.

Adrift, that's the one with the young couple? It can get hairy out there, but it's not as scary as you might think... We've been in some BIG stuff, but boats are strong, good seamanship makes a difference too.

jpender

#6: Post by jpender »

It is curious how what looks like a good seal isn't so good. One thing I've noticed with my old seals is that the outer shape is slightly different. On a new seal the edge is straight or even slightly flared from top to bottom. But the seals that leak, in addition to being larger overall, have a rounded shape in certain places on the outer face. I've wondered if this keeps them from properly engaging.

New seal:


Old seal (a particularly bad one):



My seals typically last about 10 months and really should be changed before that but I've been stubborn about it. I'm on my 4th seal in three years. Actually, after only about two months they no longer allow me to lock in as easily as compared to a brand new seal. I've tried lubing and sometimes that offers short-term symptomatic relief.

I've thought about replacing the seal more frequently. Hey, it's just $5-6. I love that smooth-as-silk operation from a new seal. It's been three months since I last replaced my seal and while it's not close to leaking that silky operation is gone.

EbenBruyns (original poster)

#7: Post by EbenBruyns (original poster) »

The shape is the same as the new one, apart from being stretched and softer. I think it's not unreasonable to replace the seal annually, that's what I did with machines on land... I'm just so used to my setup being bomb proof...

Ken5
Supporter ★

#8: Post by Ken5 »

EbenBruyns wrote:Adrift, that's the one with the young couple? It can get hairy out there, but it's not as scary as you might think... We've been in some BIG stuff, but boats are strong, good seamanship makes a difference too.
Yes, from a true story. Good Seamanship is huge!!! I grew up on Long Island and a friend of mine had a 45+ sailboat with Lea-boards and heavy ballast. We were able to go through all the shallow channels. Boat looked like a huge whale with flippers. Lol

John, my gasket did not look like yours either. :( I remembered seeing your photo and it was the first thing I looked for.

jpender

#9: Post by jpender »

EbenBruyns wrote:The shape is the same as the new one, apart from being stretched and softer. I think it's not unreasonable to replace the seal annually, that's what I did with machines on land... I'm just so used to my setup being bomb proof...
Did you check all the way around? On my old seals they look fine around most of the outside. It's just in spots that it's odd. I get some whitish discoloration in places as well.

Ken5
Supporter ★

#10: Post by Ken5 »

Sharp all around, with minimal discoloration. I kept it somewhere, if I find it I can post a photo if you are interested.