Leaky AFPR

[PonyGTrider]

Hello folks!
Just wondering, I’ve been seeing lots of people are using Kirban 5005 FPR and they’re saying “No problems”. Am I the only one having leaking issues with it? No big adjustments that could over stretch the diaphragm yet I went thru two diaphragms replacements.
What coul be wrong with it? the spring? Am I twisting the metal part in the middle of the diaphragm separating it from the rubber disc while adjusting the L wrench set screw? Can anyone describe or share the internal parts of that FPR, to see if I’m missing something? Perhaps a bearing ball on top in between of the adjusting screw and of the disc? I see a round dish pocket… This is what I have.
thank you all

 

[manicmechanic007]

Only advice I can offer is vaseline around the screw holes and the outer portion of the viton. You could massage the adjusting screw to a light rounded polish. You could also adjust it with the pressure bled off. Then recheck a few times to get it right. Good luck and buy the diaphragms in pairs

 

[90sickfox]

I run a kirban but don't want to take it apart. I've been using it for about 5 years no issues. I run ethanol free fuel. I took it apart when I first got it and replaced the little allen screws with stainless ones.

What does the bottom of your adjusting screw look like ?

 

[PonyGTrider]

Only advice I can offer is vaseline around the screw holes and the outer portion of the viton. You could massage the adjusting screw to a light rounded polish. You could also adjust it with the pressure bled off. Then recheck a few times to get it right. Good luck and buy the diaphragms in pairs

Thanks for the advice, I’ll do what you suggested

I run a kirban but don't want to take it apart. I've been using it for about 5 years no issues. I run ethanol free fuel. I took it apart when I first got it and replaced the little allen screws with stainless ones.

What does the bottom of your adjusting screw look like ?

Thank you for replying. The aluminum disc is definitely getting marked by the adjusting screw which is a typical set screw. The disc and the tip of the set scre both have a radius recess which could accommodate a bearing ball and that’s what I will do. Don’t know if that is causing the center of the diaphragm to leak, maybe the set screw is dragging the disc and spring twisting the little metal plate causing it to de-bond from the rubber/silicon of the diaphragm. Will see

 

[90sickfox]

Looks like there should be a ball in there.

 

[PonyGTrider]

Looks like there should be a ball in there.

I think so too. I polished the burs in the aluminum disc pocket and polished the little pocket on the set screw tip, placed a ~0.290" bearing ball with a dab of synthetic grease and boy what a difference! The set screw turns effortlessly without dragging and digging into the aluminum disc. Now all I need is a diaphragm replacement hopefully that little fix would make a difference on the leaking issue.
Thanks for commenting.

 

[Mustang5L5]

I thought i took pics of my Kirban when i pulled it apart last year, but I don't think I did.

I dont recall a ball in there though, but don't quote me on that.

 

[PonyGTrider]

I thought i took pics of my Kirban when i pulled it apart last year, but I don't think I did.

I dont recall a ball in there though, but don't quote me on that.

I’m almost positive there was not a bearing ball and that definitely is a flaw on kirban’s design or end product quality. After this small fix I assembled using a previous diaphragm that as far as I know was vacuum leaking. I left it on my bench under 15 inches of vacuum and after about two hours I still seeing the same vacuum value… Son of a gun I thought that diaphragm was shot!!! Will it leak at fuel contact??? I have no idea and we will see.