The Scenario -
Attempting to replace inner rear beam straps on '97 NACRA 6.0NA. Despite all firm but gentle efforts, bolts are apparently seized (one already broken). Going forward, I would like to apply some penetrating lubricant in attempt to remove the remaining bolts without damage. (Note - Not planning to reuse bolts; just want to avoid having to drill/re-tap all of fasteners).

The Problem statement -
Not having a lot of experience with fiberglass, I have a concern that the penetrating lubricant could degrade the strength of the fiberglass structure at this critical area.

The Request - I am interested to know if anyone can share experiences with penetrating lubricants that have proven to be:
A) fiberglass-safe
B) fiberglass-UNsafe.

Any reports of either will be helpful.

I have heard some testimony about those below, but interested obtaining in all available info.
- PB Blaster
- 3M penetrant? (3M Multi Purpose Spray Lubricant)
- Boeshield T-9


Thanks in advance.
Mark

PB Blaster - I have used it on catamarans for years with no problem
just wipe off any that gets on the gelcoat/fiberglass

let soak for a few days - bang on the bolts and even try to tighten them a smidge to break them free if they won't turn

I have also hear/but never tried using some acid to free frozen bolts (like sno bol) and i use that stuff on my hulls to clean them

Agree, the use of penetrating oil should have no impact on the fiberglass. Just be careful to not get it all over the place or it will turn the deck into a skating rink.

sm

PB Blaster = Best Shot. No harm to fiberglass that i am aware of.

--
Kenneth Purdy
Hobie 16
Nacra 5.2 (2)
Banshee
First Coast, Florida
--

Might consider using a battery powered impact driver, after the penetrant has had time to work, and try MN3's suggestion of bumping the bolt both directions to break it free.

Quote

Note - Not planning to reuse bolts; just want to avoid having to drill/re-tap all of fasteners).

You should def run a tap through the groves and inspect for wear

Years back, i took off a beam to replace the dolphin striker and discovered my beam bolts were loose and wobbly when threaded without the beam. Just typical wear and tear on a salt water cat, sailed hard and often (regardless of amount of after sail washes)

Ended up drilling out, and adding helicoils to every beam bolt hole on the boat (8). Also ran a die over the bolts and i seem to recall replacing them all (or some?) in the end too.

I highly recommend using lots of tef-gel after you clean the threads - the stuff lasts and works great and seems to eliminate bolts from freezing up if you use enough product - best stuff i have tried

Sorry to bring this thread back around...Just my two cents...

I believe that PB Blaster is the best available PENETRANT.I first found it about 3 years ago and it is all that I use now.

It uses capillary action to "follow" threads on a stuck object such as spark plugs,pipes,nuts/bolts,hub caps etc.It breaks the surface tension of a rust bond-that's how it is able to seep past stuck rings in a cylinder,it also works excellent if you have a stuck journal bearing because it will "pull" itself upward to the top of the bearing if you can only spray into the side of it and it creeps throughout the whole seizure with the capillary action to break the rust bond.

I don't think it is expensive at all because of the results you get,you dont have to mix anything together,you just point and spray and it has a pinpoint stream,not a mist.Some places may have liquid wrench cheaper than PB but when I last bought LW it was around $3 for 9 or 10 oz. and PB cost's me $4 (+ -) for about 15 oz. and it come's in a spray can while LW comes in a small tin dropper can.I like LW for small jobs where I can't have a mess or need only a drop or 2.

All in all it's good stuff and at a fair price for the results it delivers,it IS expensive compared to spray lubricants,but they are 2 different things,for 2 different jobs.

Try a can on your "Really tough projects" and post your results.And as with any PENETRANT give it reasonable time to do it's job.It took it a LONG time to get seized...schramm...

It doesn't compare to WD-40- because that's a lubricant.WD-40 is great for lubricating mechanisms and lite moving parts,but it is not really in the class of penetrants...