Replacing Bennett Hydraulic Lines

SmokyMtnGrady

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Greetings,
It has been a while. Last summer I did a bonehead move wiring batteries in parallel and nearly burned my boat down. In that event I melted my trim tab hydraulic lines. I have a few questions and maybe you guys have the answer.

Boat is 2008 228. Tabs factory installed.
I only need to replace the lines. At west Marine they sell hydraulic lines in 20 foot lengths.

Do any of you know the length of the lines in this boat?

If the port side is longer than 20 feet, do you know of other sources for the tubing?

I am assuming one would want a single continuous tubing from the pump to the actuator?

Any other tips on replacing the lines?
 

Halfhitch

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Bob,

They are a low pressure, low volume system. It is perfectly OK to just cut out the burned piece and install a coupler. If the burned section that you need to cut out is long enough that you don't have enough slack to pull the ends together, you can just use two couplers and put back a section the same length you cut out. I am imagining just a burned spot where a battery cable passed over it which could easily be pulled together. Most any auto parts store or trailer supply store has the couplers since that same tubing is used on a lot of trailer brake systems.
 

SmokyMtnGrady

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Bob,

They are a low pressure, low volume system. It is perfectly OK to just cut out the burned piece and install a coupler. If the burned section that you need to cut out is long enough that you don't have enough slack to pull the ends together, you can just use two couplers and put back a section the same length you cut out. I am imagining just a burned spot where a battery cable passed over it which could easily be pulled together. Most any auto parts store or trailer supply store has the couplers since that same tubing is used on a lot of trailer brake systems.

Thanks! When I removing the burned up lines I noticed they were kind of flimsy as it were. When you mention trailer brake lines I was like ding ding ding. That's what the stuff reminds me of for sure.
 

Parthery

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In the past, Tabman would have known the exact length and helped you get your hands on them. RIP

But - it might pay to reach out either to GW Customer Service or to Bennett....they may know the exact length and/or make you a deal on replacements.
 
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glacierbaze

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The hydraulic pump(HPU V351) is mounted somewhere near the transom, so it is unlikely that you can't reach your tab with 20 feet of tubing. The system is self-bleeding, so when you get it repaired, just run the tabs full up to full down a few times.
 

Ky Grady

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The hydraulic pump(HPU V351) is mounted somewhere near the transom, so it is unlikely that you can't reach your tab with 20 feet of tubing. The system is self-bleeding, so when you get it repaired, just run the tabs full up to full down a few times.

His is located where mine is, in the cabin, starboard side box, 20' would be tight avoiding any 90° bends.
 
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Parthery

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I've never had one either where the pump wasn't either under the console or in the cabin.
 

DennisG01

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I think location all comes down to the manufacturer and the styling/configuration of the cockpit. Before Grady, I had never heard of the motor being mounted anywhere BUT the transom. Actually, in MY Grady, it's mounted at the transom. And, working in the industry, I see A LOT of boats (and have owned quite a few, as well!). But in our specific area, a Grady "style" boat is not that popular.

But along with what was said above, I don't see why you couldn't splice it. When installing dual cylinders, you install a T connector - not much different than a barb splicer. However, I wonder if the barb was installed in only one tube... would it affect the speed at which the two tabs operate? For some reason, and somebody feel free to correct me, I thought I remember reading that the tubes should always be the same length (left to right sides) to avoid this? If that's true, then having the barb (restriction) in only one tube could do the same thing.
 

Halfhitch

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Actually you never use a barb fitting for these lines it reduces the internal diameter causing a restriction and will leak. The lines are actually a nylon product and is used extensively in the air brake lines on heavy trucks. The nylon material is compatible with a wide range of fluids like oil, brake fluid and such. The product is considered a tubing so is measured as an O.D for fittings and such. The Bennet lines are 1/4 in. O.D. The compression fittings are different from copper compression fittings in that there is a brass sleeve inside the fittings that support the internal diameter and a compression ferrule on the outside so a sufficient compression load can be applied to prevent leakage. Do not use a copper tubing compression fitting as it will leak as a barb type will also. Here is a link to the proper fitting. There are several views of the fitting from different angles so you can see inside. The price seems silly but I did not shop for pricing. The best place to find them is at a truck shop for heavy trucks if you have one nearby.
https://www.amazon.com/Legines-Bras...mpression+fitting+for+1/4+inch+nylon+air+line
 

DennisG01

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Actually you never use a barb fitting for these lines it reduces the internal diameter causing a restriction and will leak. The lines are actually a nylon product and is used extensively in the air brake lines on heavy trucks. The nylon material is compatible with a wide range of fluids like oil, brake fluid and such. The product is considered a tubing so is measured as an O.D for fittings and such. The Bennet lines are 1/4 in. O.D. The compression fittings are different from copper compression fittings in that there is a brass sleeve inside the fittings that support the internal diameter and a compression ferrule on the outside so a sufficient compression load can be applied to prevent leakage. Do not use a copper tubing compression fitting as it will leak as a barb type will also. Here is a link to the proper fitting. There are several views of the fitting from different angles so you can see inside. The price seems silly but I did not shop for pricing. The best place to find them is at a truck shop for heavy trucks if you have one nearby.
https://www.amazon.com/Legines-Brass-Tubing-Fitting-Compression/dp/B0773LXX9L/ref=sr_1_2?ie=UTF8&qid=1550784139&sr=8-2&keywords=compression+fitting+for+1/4+inch+nylon+air+line
Yes, 100% correct. As soon as I read the first few words of your post I kicked myself. I've installed enough trim tab systems over the years to where I should have known better than to generalize! I've never "spliced" that tubing, but am certainly familiar with the type of fittings you are referencing. Thanks for the correction.
 

SmokyMtnGrady

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You guys are on it! After several phone calls , I have it. Bennett makes the length specific to my boat. It's 25 feet long. They don't retail it and Grady doesn't supply the part either. So between Grady, Seeles Outboard in Mt. Pleasant and Bennett I am getting a custom order set with ferules, compression fittings and 25 feet of tubing x2. I am thankful all involved agreed to help me out. On the open market you can buy 20 foot lengths and kits but not 25. I think because I am the original owner and It's a Grady it all worked out. Who knows? I am grateful for everyone here giving some advice. I am thankful for Grady, Bennett and Seeles all working towards a solution for me.