Frozen pss shaft screws - any ideas on how to remove?

[samoorelex]

I'm looking for suggestions on how to unfreeze the allen head screws in my PSS shaft seal.
The seal leaks when the prop turns > 1000 RPM's way more than it should.

Does anyone have a good suggestion on how to unstick these guys?

I need to loosen these allen screws so I can compress the seal.
I had the system redone last June as per the 6 yr maintenance when we were on the hard.
I'm a long way from the yard or I would be back there.
I'm in a marina but I can't get any work done because of COVID.
We would really like to get moving north in a couple of weeks and this is a mess.

Here is what I have tried so far:
Allen wrenchs - broke one, bent one (not the sturdiest)
Heat (put soldering iron on the allen screw) trying to melt any loctite
Lubricant (50/50) mix of ATF and Acetone - PB Blaster as well
Taping allen wrench with hammer

As I understand it, there is a second allen screw under this one. The top one serves as a lock -doing a fine job if I might add.

I have one suggestion - get a dremel tool and a diamond bit. Drill out the screw not touching the threads. I'm not sure I'm skilled enough to not ruin the threads.
We are still in the water.

I'm interested in any and all suggestions.
It's possible just to run with the leak but I hate pouring copius amounts of seawater in the bilge.

Looking for an epiphany.
Sam
Sabre 402

[slug]

Originally Posted by samoorelex

I'm looking for suggestions on how to unfreeze the allen head screws in my PSS shaft seal.
The seal leaks when the prop turns > 1000 RPM's way more than it should.

Does anyone have a good suggestion on how to unstick these guys?

I need to loosen these allen screws so I can compress the seal.
I had the system redone last June as per the 6 yr maintenance when we were on the hard.
I'm a long way from the yard or I would be back there.
I'm in a marina but I can't get any work done because of COVID.
We would really like to get moving north in a couple of weeks and this is a mess.

Here is what I have tried so far:
Allen wrenchs - broke one, bent one (not the sturdiest)
Heat (put soldering iron on the allen screw) trying to melt any loctite
Lubricant (50/50) mix of ATF and Acetone - PB Blaster as well
Taping allen wrench with hammer

As I understand it, there is a second allen screw under this one. The top one serves as a lock -doing a fine job if I might add.

I have one suggestion - get a dremel tool and a diamond bit. Drill out the screw not touching the threads. I'm not sure I'm skilled enough to not ruin the threads.
We are still in the water.

I'm interested in any and all suggestions.
It's possible just to run with the leak but I hate pouring copius amounts of seawater in the bilge.

Looking for an epiphany.
Sam
Sabre 402

The beauty of Allen head fasteners is that they are easy to drill out

The Allen head self centers the drill bit

Drill them out

Use a sharp bit turning at very slow speed

If you want to give extraction one more try use a Torx bit , slightly larger than the Allen head

Drive the bit in with hammer , then give it a try

Sometimes I can break the fastener free

[Jim Cate]

Since these screws are usually set with Loctite, try using more heat than you can get with a soldering iron. From memory you need to get the temp up to somewhere between 200 and 300 F to break down the Loctite.

Jim

[jamhass]

We replaced our PSS seal last year. Same problem. Solution involved heat, penetrating oil, more heat, impact driver, more heat ... ALL applied with patience and gentle persuasion. Don't drill except as last resort, or plan to replace the entire seal.

[Fuss]

Not the final solution but to buy you some time....Why does it leak? How old is it. Is it leaking out the breather or the carbon surface? Can you re tension by moving the boot forward? As you broke an Allen wrench and bent one, I would suggest they are not good enough quality. Small Allen wrenches must be very good quality or you will get problems.

[Pizzazz]

Another temporary solution to get you going is to put a disk between the shaft and gearbox. A piece of starboard should do but there are special couplers available as well. I have never seen one of these leak by the way. It is a very unusual situation.

[gonesail]

if there is such a thing as a hardened hex bit then get that and use small breaker bar to turn the screw. in addition to heat to release the loctite.

[south4320]

Use a good quality allen key socket that fits a 1/2 inch drive socket wrench
I recently replaced my shaft seal and it was relatively easy but I couldn't undo it with an ordinary allen key.

[a64pilot]

Jest and beat, best in this example means an impact, one of the sockets pictured above is a good choice.
Do NOT drill, not as long as an Allen wrench will work, you only drill when you can’t get a tool to work cause it’s stripped, then you drill, cause you have no choice.
Odds of drilling it out and not affecting the threads is small, if you drill expect to drill and tap or install an insert.
Surely the collar is available as a single piece, maybe order one?

Assuming you get them out, flip the screws so that the one that “bites” the shaft isn’t used twice, they are only good for one use.

[Dymaxion]

You may have luck using a cordless drill/driver and correct snug fitting Allen bit. NOT an automobile repair impact driver, Milwaukee or Dewalt handyman version. Keep it pressed solidly into the screw and let the impacts do their work.

[Scrimshaw4]

The shaft seal can leak for reasons other than lack of comression. Sometimes it will happen as a result of contamination on one of the surfaces. Try pushing the bellows back and inserting emery paper between the disks and rotating the shaft. The water will also flush the disks when you separate them. Just a thought.

[SV__Grace]

Originally Posted by Dymaxion

You may have luck using a cordless drill/driver and correct snug fitting Allen bit. NOT an automobile repair impact driver, Milwaukee or Dewalt handyman version. Keep it pressed solidly into the screw and let the impacts do their work.

Having an older, european boat I have lots of experience with stuck screws!

I do have a recently installed PSS and can confirm it uses two screws, the top as a locking screw.

Cautionary note- I've broken many bits and stripped many screws trying to get them out with a Home Depot cordless Ryobi impact driver. Only try it with a hardened bit that fits tightly in the allen screw.

I've had better luck with lots of heat and banging on the screw with an old school hand held, knuckle-bruising, non-electric impact driver like this

BTW, the best penetrating oil I've found, recommended by the boatyard guys, is Aero Kroil

There have been times for me when the process of using the above was beyond my patience and it was more efficient and effective to drill it out. If you damage the threads a correctly sized tap will fix that (I've had to invest in SAE and Metric tap and die sets), and a screw extractor makes it easier (be sure it's good quality and hardened as well, I've broken them too!).

BTW- I do have a small leak that I thought was the PSS but the yard traced it to the seal between the fiberglass and shaft log (tube) the that PSS is clamped onto. It will need to be removed and reinstalled sometime in the future but the size of the leak is small for now.

[Russ]

PB Blaster and patience. Remember to spray, tap the screw to set up vibrations, and wait an hour or so. The Key to these is to treat them like a tap and die tool. Back out as far as you can then retighten and back out again and repeat till it finally gets loose. Mine took an hour to get out with gentle persuasion. This is NOT a job for a Breaker bar or Impact driver, you'll break it off deep inside for sure.
And YES a PSS Seal is not supposed to leak AT ALL! Once out, the inner set screw came out easily.
Russ

[MJH]

Originally Posted by samoorelex

I'm looking for suggestions on how to unfreeze the allen head screws in my PSS shaft seal.
The seal leaks when the prop turns > 1000 RPM's way more than it should.

Does anyone have a good suggestion on how to unstick these guys?

I need to loosen these allen screws so I can compress the seal.
I had the system redone last June as per the 6 yr maintenance when we were on the hard.
I'm a long way from the yard or I would be back there.
I'm in a marina but I can't get any work done because of COVID.
We would really like to get moving north in a couple of weeks and this is a mess.

Here is what I have tried so far:
Allen wrenchs - broke one, bent one (not the sturdiest)
Heat (put soldering iron on the allen screw) trying to melt any loctite
Lubricant (50/50) mix of ATF and Acetone - PB Blaster as well
Taping allen wrench with hammer

As I understand it, there is a second allen screw under this one. The top one serves as a lock -doing a fine job if I might add.

I have one suggestion - get a dremel tool and a diamond bit. Drill out the screw not touching the threads. I'm not sure I'm skilled enough to not ruin the threads.
We are still in the water.

I'm interested in any and all suggestions.
It's possible just to run with the leak but I hate pouring copius amounts of seawater in the bilge.

Looking for an epiphany.
Sam
Sabre 402

I just viewed a penetrating oil test on You Tube and Seafoam came out the winner. Give it a try.

~ ~ _/) ~ ~ MJH

[bongo]

As mentioned above, more heat if it has red Locktite. If corrosion is the issue heat and dab beeswax to the threads, it wicks right in. High quality Allen socket and impact tool. If galling is the issue, good luck. If you need to drill it out, I’ve had good luck with left handed drill bits/easy-outs. Drilling stainless steel requires at least high speed steel drill bits, lubrication, low speed high feed rates. DON’T break the bit! I’ve spent a career getting stuck fittings apart, and they almost always do, (almost)