New Pitot tube assembly doesn't match old one

[CaliCash]

Hi everyone. I'm still fairly new to this site and am ADDICTED. Last season a buddy of mine accidentally broke the pilot tube assembly for the speedometer (the part that hangs down beneath the boat). I went and got a new universal one from westmarine (it's local to my house) and noticed the wholes don't match up. There are 2 parts to my question.

1. Is there anything special I need to do when drilling into the fiberglass/gelcoat when installing the new assembly?

2. What would I use to fill those 3 tiny screw holes that are currently there from the old pilot assembly?

Thanks in advanced fellas!

Edit: I fixed your title to piTot tube . . . QC

 

[smokeonthewater]

Re: New Pilot tube assembly doesn't match old one

Re: New Pilot tube assembly doesn't match old one

it's a pitot tube....

sand, clean and fill with 2 part epoxy....

Drill with wood bit and seal hole with 3m 5200 or 8200 sealant....

DO NOT use silicone EVER

Good luck and have fun

 

[CaliCash]

Re: New Pilot tube assembly doesn't match old one

Re: New Pilot tube assembly doesn't match old one

Sweet, thanks for the info! I'll be tackling this today when I get home from work. Kinda leery of filling and drilling holes into the hull, especially below the water line. Wish me luck!

 

[180shabah]

Re: New Pilot tube assembly doesn't match old one

Re: New Pilot tube assembly doesn't match old one

uhh - good luck...


What did you get to seal the old and new holes?

 

[CaliCash]

Re: New Pilot tube assembly doesn't match old one

Re: New Pilot tube assembly doesn't match old one

I just went to westmarine today and they told me 3M 4200 was the better stuff for this job. So that's what I got. Should I take it back and get the 3M 5200? They didnt have 3M 8200.

 

[tschmidty]

Re: New Pilot tube assembly doesn't match old one

Re: New Pilot tube assembly doesn't match old one

5200 is slightly better (supposedly more permanent) but 4200 will do the job.

 

[Philster]

Re: New Pilot tube assembly doesn't match old one

Re: New Pilot tube assembly doesn't match old one

You're good to go.

 

[QC]

Re: New Pilot tube assembly doesn't match old one

Re: New Pilot tube assembly doesn't match old one

4200 vs. 5200 is a constant debate, you're good.

 

[CaliCash]

Re: New Pilot tube assembly doesn't match old one

Re: New Pilot tube assembly doesn't match old one

Ya, I've been reading that. From what I gather, they both are good and will hold, but 5200 is slightly more permanent then 4200. As long as I dont take on water I'm good. haha. Again, thank you all for your help! I sure do like this forum!

 

[JimS123]

Re: New Pilot tube assembly doesn't match old one

Re: New Pilot tube assembly doesn't match old one

DO NOT use silicone EVER

Why?

There are silicone marine products specifically made for below the waterline. I agree that 5200 is the best, but why not silicone?

 

[cr2k]

Re: New Pitot tube assembly doesn't match old one

Also, after you drill new holes you will want to slightly countersink them to prevent the gelcoat from chipping off when you put new screws in.

Silicone is not good for constant water submersion. It tends to debond.
It is sticky as all get out when it is soft, but after it sets it can come off fairly easy. Always look for products that are made for under water or constant water sealing/bonding. It works good in the shower/bath because it is just a shield and the water runs off.

The silicone products that are made for below the water are usually not 100% silicone and are blended with other stuff for better adhesion.

 

[180shabah]

Re: New Pitot tube assembly doesn't match old one

never heardof 8200 - probably a typo.

Agree that 4200 is a better choice for the pitot screws. You will be replacing it again eventually, the 5200 would make it a real chore.

I would use an epoxy product for the old holes, but the 4200 will work.

 

[smokeonthewater]

Re: New Pilot tube assembly doesn't match old one

Re: New Pilot tube assembly doesn't match old one

Why?

There are silicone marine products specifically made for below the waterline. I agree that 5200 is the best, but why not silicone?

Simply put.... because 5200 is the best and is readily available..... after all while dry leaves will work to wipe with you would never choose them over charman.



as for 4200 it's no typo.... I'm not sure but I believe it is replacing 8200
I am certain that it exists however