So who has cracks in their bilge gel coat?

sfergson727

Well-Known Member
PLATINUM Sponsor
TECHNICAL Contributor
Oct 12, 2007
12,916
Washington Park Marina, Michigan City
Boat Info
'89 Sea Ray 390 Express
'00 Sea Ray 185 BR
Engines
mercruiser 7.4L inboards
Mercruiser 4.3L/Alpha 1
I was getting the boat ready for spring, which includes cleaning the bilge (one of my least favorite activities).
I hadn't cleaned the silt from when I drained the engines, so it sat over the winter in a dismal state...no water just dirt. Doing so, I was, for the first time, able to see some cracking that has occurred on the bilge floor.

IMG_5600.jpgIMG_5598.jpgIMG_5599.jpg

These photos are taken while laying on top the port engine, looking at the bottom of the hull, next to the stringer for the engine mounts. The cracks DO NOT go upwards into the stringer.

My mechanic believes that they are superficial, just the result of too much gel coat sprayed into the radius, but I wanted to see if any of you are experiencing the same issue, and your thoughts as to how common this is.

I am going to have them grind out some of the cracks to investigate whether they penetrate the fiberglass below, and yes, I am going to clean the bilge.

Thanks in advance for your thoughts,
Scott
 
Last edited:
Is that just gel coat or has it also been painted?


Sent from my iPhone using Tapatalk
 
OMG Scott! You better sell it!

Simple Spider Cracks. Clean the bilge and let it go...
 
Last edited:
Very common. Not a structural problem. Clean and touch up with bilgekote.
 
Very common. Not a structural problem. Clean and touch up with bilgekote.

Clean up, yes. Coat with bilgecoat, not so sure. I seem to recall someone knowledgeable (FrankW?) stating that SR uses a bilge gel coat infused with wax, or some other surface lubricant, that makes overcoating ineffective. If so trying to overcoat it might it cosmetically worse.

I don't know if this is an accurate recollection, but I do know I had a heck of time getting our Doc signboard to stick to bilge gel coat using epoxy. So there may be some truth to it.

Henry


Sent from my iPad using Tapatalk HD
 
Guilty as charged. Bilge gelcoat does have a wax component so it repels water and oil.

You are on the right track, Scott. The cracks should be ground out to verify they are in the gelcoat only (seems like I remember you hit an obstruction sometime in the past) leaving the area rough with a good tooth for new gelcoat. Then the repair area needs to be scoured with acetone on an abrasive pad then bilgecoat can be brushed on. Use care with the acetone cleaning and go well outside the area where the gelcoat will be brushed on. If you don't it will not bond and at some future point the gelcoat painted over the old bilge coat will flake off where the wax was not cleaned away.
 
Thanks Frank, and to all the others who chimed in. I did hit a log a couple years ago, and it was that side of the boat that took the brunt of the hit.

Have a great weekend.
 

Forum statistics

Threads
112,942
Messages
1,422,695
Members
60,926
Latest member
dander88
Back
Top