Core Moisture

[Woodsmaster59]

I am looking at a mid 80 Jenne with teak strips mounted in the cockpit floor and seating area. There are indications on the interior that those have leaked. (headliner stained). How concerned should I be about the balsa core and how would I check for any serious damage.

[Woodsmaster59]

Also the fuel tank has been disconnected from the motor. The seller says that the fuel tank does not meet USCG standards because of the configuration of the tank itself. He told me that the outlet is on the bottom which is a safety concern. The tank is enclosed in glass and seems as if it would be a difficult refit. Thoughts?

[Woodsmaster59]

Temporary tank set up for systems check? Would it be safe to (rig if you will) a outboard tank with a return to hook up to this Yanmar to start it and see how she runs?

[HappyMdRSailor]

Originally Posted by Woodsmaster59

I am looking at a mid 80 Jenne with teak strips mounted in the cockpit floor and seating area. There are indications on the interior that those have leaked. (headliner stained). How concerned should I be about the balsa core and how would I check for any serious damage.

If after you remove the strips the deck does not flex, you are probably OK to not worry about extensive core damage... Clean out your fastener holes using the hex key drill method, pot with thickened epoxy... re-teak, or deck paint...

Originally Posted by Woodsmaster59

Also the fuel tank has been disconnected from the motor. The seller says that the fuel tank does not meet USCG standards because of the configuration of the tank itself. He told me that the outlet is on the bottom which is a safety concern. The tank is enclosed in glass and seems as if it would be a difficult refit. Thoughts?

This completely defies logic... Is this an OEM install, or some PO bastardization ????

Originally Posted by Woodsmaster59

Temporary tank set up for systems check? Would it be safe to (rig if you will) a outboard tank with a return to hook up to this Yanmar to start it and see how she runs?

Totally safe... you can use a 5 gal jug with 2 lines fed in the neck...

[Fiveslide]

Originally Posted by HappyMdRSailor

If after you remove the strips the deck does not flex, you are probably OK to not worry about extensive core damage...

He's just looking at it so I don't think he will be able to go to these lengths during his prepurchase inspection.

Assume the worst and adjust your offer accordingly is the only way. However, if you fix the leaks and even if the area goes a bit spongy one day I doubt it will be anything more than an annoyance and never affect the boat in any other way.


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[Nicholson58]

Originally Posted by Woodsmaster59

Also the fuel tank has been disconnected from the motor. The seller says that the fuel tank does not meet USCG standards because of the configuration of the tank itself. He told me that the outlet is on the bottom which is a safety concern. The tank is enclosed in glass and seems as if it would be a difficult refit. Thoughts?

Bottom pipe is OK for diesel. Is it gas? Gas must be on top. This can probably be modified.

Check the moisture with a meter from the inside of the boat.

[Woodsmaster59]

It is in fact a diesel motor. And yes on the core issue I am looking at it to buy, I just want a fixer upper not a multiyear project. So if the cockpit surfaces seem solid I should be able to repair and be ok? This is a install from the factory. I read a post from another Jenne owner that this is a common issue and repairs are fairly simple as long as the deck is firm.

[HappyMdRSailor]

Originally Posted by Woodsmaster59

It is in fact a diesel motor. And yes on the core issue I am looking at it to buy, I just want a fixer upper not a multiyear project. So if the cockpit surfaces seem solid I should be able to repair and be ok? This is a install from the factory. I read a post from another Jenne owner that this is a common issue and repairs are fairly simple as long as the deck is firm.

It really shouldn't be an issue... Even if there is more core rot than you would care for... Replacing the teak will reinforce is enough.... You simply need to remove what you can... dry it out... and stop further intrusion...

[a64pilot]

Originally Posted by Fiveslide

He's just looking at it so I don't think he will be able to go to these lengths during his prepurchase inspection.

Assume the worst and adjust your offer accordingly is the only way. However, if you fix the leaks and even if the area goes a bit spongy one day I doubt it will be anything more than an annoyance and never affect the boat in any other way.


Sent from my SCH-S738C using Cruisers Sailing Forum mobile app

Stupid question, but we "fix" voids in aircraft honeycomb by drilling holes and injecting a resin of some sort into the void, adds weight of course but does return structural integrity. In a case like this, couldn't you drill a couple of holes and inject epoxy until it ran from the other holes?

[HappyMdRSailor]

Originally Posted by a64pilot

Stupid question, but we "fix" voids in aircraft honeycomb by drilling holes and injecting a resin of some sort into the void, adds weight of course but does return structural integrity. In a case like this, couldn't you drill a couple of holes and inject epoxy until it ran from the other holes?

This is precisely the method... of many different degrees.... If you are not going to "scalp and replace" the core...

[Woodsmaster59]

You guys are freakin awesome. I love this place. Always people there with knowledge to offer advice. So...the seller (broker) told me that the fuel line to the motor is disconnected to the motor because the configuration does not pass USCG because it is plumbed from the bottom...I should suspect......???? He offered to allow me to run a temp auxiliary set up to try and start the motor. Are fuel tank leaks in factory install common? Full of sludge or excessive water maybe? Owner forum member with the same boat only 2 years older said these came with a "flexible" water tank that should be replaced. Anyone familiar with these?

[Stevens 47]

Originally Posted by Woodsmaster59

It is in fact a diesel motor. And yes on the core issue I am looking at it to buy, I just want a fixer upper not a multiyear project. So if the cockpit surfaces seem solid I should be able to repair and be ok? This is a install from the factory. I read a post from another Jenne owner that this is a common issue and repairs are fairly simple as long as the deck is firm.

If it was me I would have a really good look at a possible balsa wet core. You should determine if the core is wet or if it is leaking and how you would repair it. I do not want to sound an alarmist but core replacement is a big job. If the core is sound were are the leaks and staining coming from. The best way is to find someone with a thermo imaging (surveyor) device this will tell you if the core is wet.

[Stevens 47]

Originally Posted by a64pilot

Stupid question, but we "fix" voids in aircraft honeycomb by drilling holes and injecting a resin of some sort into the void, adds weight of course but does return structural integrity. In a case like this, couldn't you drill a couple of holes and inject epoxy until it ran from the other holes?

I would not do this with a wet balsa core. It is very hard to dry it. If its wet and has been wet for a while chances are that it will be in various stages of rot. No amount of resin injection will fix that and how did the water got into the core has still not been determined.

[HappyMdRSailor]

Originally Posted by Woodsmaster59

You guys are freakin awesome. I love this place. Always people there with knowledge to offer advice. So...the seller (broker) told me that the fuel line to the motor is disconnected to the motor because the configuration does not pass USCG because it is plumbed from the bottom...I should suspect......???? He offered to allow me to run a temp auxiliary set up to try and start the motor. Are fuel tank leaks in factory install common? Full of sludge or excessive water maybe? Owner forum member with the same boat only 2 years older said these came with a "flexible" water tank that should be replaced. Anyone familiar with these?

You can absolutely count on an "disconnected" fuel tank being full of crap... The ONLY way to get it clean is by "physically" scrubbing it down... Cut access to the tank, and investigate... Fuel tanks leak all of the time... Find out what it's made of and assess.... I would figure in $500 for a new tank, all your accessories and materials... That way if you find your current tank to be perfectly clean... leak free... and be able to be plumbed correctly... You will be a very happy camper!

Originally Posted by Stevens 47

If it was me I would have a really good look at a possible balsa wet core. You should determine if the core is wet or if it is leaking and how you would repair it. I do not want to sound an alarmist but core replacement is a big job. If the core is sound were are the leaks and staining coming from. The best way is to find someone with a thermo imaging (surveyor) device this will tell you if the core is wet.

Agreed !

Core replacement is filed under "one of the most extensive crap jobs ever"...

A drill bit, and or hole saw, are the crude tools here... We need to epoxy holes anyway... Might as well do a few exploratory pokes...

[a64pilot]

A couple of iff here, but if you could plug the water intrusion areas and if you could hole saw a few say 1" holes in the bottom, wouldn't it eventually dry out? May take a long time maybe even months, but wouldn't it dry out? Having to re-core a deck is one of the few things that make me pass on a boat, I've never done it, and don't want to learn