Brass Bushing Sealant...?

[charliehows]

My somewhat ancient hydraulic helm pump seems to have developed a leak in the very tight space between the alloy end casing and the brass bushing that carries the 'o' ring steering shaft support. The brass bush slides out without much pressure but its a fairly tight engineered joint. My question is; what, in your opinion, is the correct sort of sealant I can apply that may help seal this leak.

couple of considerations; 1;its a non-pressurized unit (swash plate piston pump)- theres an open vent in the fillercap; 2;there are no heat issues 3;fluid used is dexron atf

[boden36]

Perhaps the best way may be to machine the hole and press in an oversized bush (or even a slightly oversize bush without machining the hole if it is unworn.
Otherwise you could try machining a groove in the outer diameter of the bush to take an 0 ring.
Maybe simpler to first try a Loctite or similar bush retainer but make sure the parts are surgically clean first.


Regards,
Richard

[a64pilot]

A bushing that is a press fit has become loose?
you you can have it knurled, or of course replace it, stake it, or if I understand the issue, put it in with red Loctite.
One of the uses for red Loctite is to secure bearings in, it works better than you may think.
However if I understand your issue, I’d stake it. You can stake with a marking punch put the punch between the bushing and what it fits in and smack it, it will upset the metal slightly and make for an interference fit.

[charliehows]

i put it back together yesterday with hylomar - dont know if its going to hold up - i used to use it on shovelhead valveguides - freeze the guide, put the head in the oven, bit of hylomar, slide her in. One consideration is being able to remove it again - thought about loctite but i'm not sure which type would both seal and allow future removal. Thanks for your thoughts.

[a64pilot]

Anything that can be heated to 400f will cause red Loctite to deteriorate to pretty much powder, but you can play hell with it if you can’t heat it.
Freezing the guide and heating the Head was the magic of the valve guides, the hylomar didn’t hurt, but wasn’t necessary.
Use to bore and resleeve Kawasaki 900’s back in the day, froze the sleeves and heated the block, drop in fit, but when temp equalized, they weren’t coming apart. Just make sure you get it in all the way quick, if it stuck halfway you knew what you were going to be doing the rest of the day usually.
We could take Kawasaki 900’s all the way to 1327 without stroking the crank.

[Compass790]

Loctite 609 is a bush retainer that works

[charliehows]

The bush doesnt have any propensity to come out - it is, after all, a hand driven, low pressure unit with no longitudinal force acting on the bush. I'm reluctant to use a high strength adhesive where a sealant is the appropriate tool - I dont care how well the bush is held in, just that it leaks a bit.
let me try to put the problem more succintly; I wonder if there is a product that will act as a sealant without making future removal of the bushing very difficult? Most loctite products seem to focus on retaining or bonding, with sealing as a byproduct of those functions; I'd prefer to use something that is designed to seal without forming a strong adhesive bond - kind of like the idea with a good knot - it has to hold but it also has to undo...

[Compass790]

Loctite is a name that frightens people but the adhesive comes in many different strengths. Loctite doesn't actually mean it locks it really tight None of them really make it impossible to remove a bush. Some grades make it a lot harder like 609 or 272. I have no relationship to Loctite, just a lot of experience with the goo since the 70's.However now I understand you want a low strength sealant. just plain silicone may work or Loctite master gasket or Loctite hydraulic pipe sealant or Omnifit or Permatex gasket replacement. I'd suggest hydraulic pipe sealant after re-reading yr post

[charliehows]

Originally Posted by Compass790

Loctite is a name that frightens people but the adhesive comes in many different strengths. Loctite doesn't actually mean it locks it really tight None of them really make it impossible to remove a bush. Some grades make it a lot harder like 609 or 272. I have no relationship to Loctite, just a lot of experience with the goo since the 70's.However now I understand you want a low strength sealant. just plain silicone may work or Loctite master gasket or Loctite hydraulic pipe sealant or Omnifit or Permatex gasket replacement. I'd suggest hydraulic pipe sealant after re-reading yr post

I LOVE loctite - held various of my harleys together very well over the years...I'll take a look at the hydr. pipe sealant - might be just the ticket...thanks

[mickt243]

Might pay to try loctite 567 ‘master pipe sealant’ , it’s effectively a tube of thread tape and is designed to act as such, it will only seal minor gaps, but it prevents galling and allows for future disassembly. I have used I to seal friction fit low pressure parts in the past and it worked fine - but be aware, it is not a retaining compound, in some instances it can assist a friction fit joint to self disassemble....