STEEL RAILS

Mar 22, 2022
77
hunter legend nj
Hi Guys I have 1987 hunter 40 ft legend with a Ynamar 4jh-e engine
Problem is the boats inner steel rail that the engine mounts on is rusting
badly to the degree that the rust come off in thin layers
That can be dome with that type of problem short of pulling the engine an replacing the inner rails
with stainless steel rail then remount everything
Please advise Rick
 

JamesG161

SBO Weather and Forecasting Forum Jim & John
Feb 14, 2014
7,770
Hunter 430 Waveland, MS
Clean the rails, prime it with Rustoleum Rust Preventer, and paint.
Jim...
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
23,159
CAL 35 Cruiser #21 moored EVERETT WA
Rick.
Get into the engine bay and assess the condition of the metal used. How much metal is remaining. You are talking about metals that are 35 years old. I suspect you have no knowledge of how the boat has been cared for over the past 35 years.
  1. Was the boat sunk at one point in time?
  2. Was there a time when salt water sat in the bilge at the level of the mounts?
  3. What is the condition of the mounts?
You ask should I be replacing the part that supports the engine and ties it securely to the hull? Depends on the level of corrosion that is destroying or has destroyed the metal. Corrosion is like a cancer. Rust is the evidence that your metal parts has the cancer.

Paint covers the rust, but does nothing to make the engine secure.

Only you can assess the level of strength/weakness and so decide if the condtion renders the boat safe or at risk for you and crew.
 
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capta

.
Jun 4, 2009
4,935
Pearson 530 Admiralty Bay, Bequia SVG
There is no reason at all to pull the engine. Just build yourself an A frame strong enough to lift the engine, and hoist it up high enough to replace the engine frames. Cheap, easy and safe.You may have to undo a few hoses, but probably not many more electric wires than the cables to the starter.
 
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Mar 22, 2022
77
hunter legend nj
What do you mean by engine frame ???
do you mean the 4 steel an rubber engine shock mounts if so they look to be ok
the problem lies in the steel rail that they mount to
 
Mar 22, 2022
77
hunter legend nj
John I agree with that your saying is there any type of material that i can attach to the rails to give some added strength
or is there a compound that i can purchase an mix up an pour over the rusted steel sealing it of an giving it added strength ????
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
23,159
CAL 35 Cruiser #21 moored EVERETT WA
Rick. Simple answer is No. If the steel is there and has deteriorated to a point that the strength is compromised, then you will need to replace the material to return the expected strength.

Note different manufacturers use different means. My boat has thick fiberglass stringers that run along the base of the engine space. Other boat owners have wooden stringers. It sounds like your manufacture or a previous owner installed steel over fiberglass. They appear to have lasted 35 years. You can lift the engine as wisely suggested by @capta. You can replace with painted steel. I would think SS would not be advised. This might need to be researched with a marine engineer. You could inquire with your manual to see what was spec'd.

Put some pictures of the issue here. With out some concrete information it is all speculation.
 
Mar 22, 2022
77
hunter legend nj
Ok thanks John so what you are saying is the steel rails that are there may only be bolted down to the inner fiberglass stringer i will have to take a close look at this if that the case then i can lift the engine a little an maybe remove the rusted steel rails an install new st steel rails an also new motor mount at the same time
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
23,159
CAL 35 Cruiser #21 moored EVERETT WA
Yes. It is all starts with a careful "Inspection".

A nice bright flashlight. A tool to measure the thickness of the material.
How the mounts are secured to the boat.

Take pictures.
 
Mar 22, 2022
77
hunter legend nj
Hi John I will be going to her this coming week end
to get pictures an develop a plan of that can be done
Why did you state that you would not use stainless steel to remake the rails
i would of thought that would be the best material
 

JamesG161

SBO Weather and Forecasting Forum Jim & John
Feb 14, 2014
7,770
Hunter 430 Waveland, MS
Why did you state that you would not use stainless steel to remake the rails
I would have said the same.

Try not to mix metal types that are in contact on the boat.

If your mounting bolts are regular Carbon Steel, the stay with similar rail.
You noted Rust on the rails, thus not Stainless.
______
Your rusty rails can loose almost 50% of their thickness before I would worry.
Jim...
 
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Mar 22, 2022
77
hunter legend nj
Well that is something to consider to use similar type of materials on it i did not notice an rust on the motor mounts may be st steel
An you may be correct in saying that the rail still may be good even if 50 % of it is rusted away
will be taking my veneer along to determine the thickness of the good metal left
considering that the 4jh-e yanmar uses 4 motor mounts using 8 bolts to attaché it to the rails

This all started then i was winterizing her an looked at all the rubber hose that should be replaced after 35 yrs

I will be going to her this week end an can better check things out an get pictures of it
Thanks Jim
 
Jan 19, 2010
12,568
Hobie 16 & Rhodes 22 Skeeter Charleston
Would it make sense to bolt a zinc to the rail? Someplace low so the zinc would be in contact with water in the bilge?
 
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JamesG161

SBO Weather and Forecasting Forum Jim & John
Feb 14, 2014
7,770
Hunter 430 Waveland, MS
Would it make sense to bolt a zinc to the rail? Someplace low so the zinc would be in contact with water in the bilge?
:plus:

You can also connect the keel bolts to the same Zinc , with an insulated wire.

Jim...
 
Mar 22, 2022
77
hunter legend nj
Well it may not work for the eating away of the engine rails is do to rust

the Zinc is used to prevent the electrolysis of the metal

I realty don't know that much about it
 

JamesG161

SBO Weather and Forecasting Forum Jim & John
Feb 14, 2014
7,770
Hunter 430 Waveland, MS
Well it may not work for the eating away of the engine rails is do to rust
This is true.

Did you ever see a galvanized fence post or roofing metal?

Why did they Zinc coat them?

So it would not hurt having the rails connected with another sacrificial metal.

Jim...
 
Mar 22, 2022
77
hunter legend nj
Well i can give it a try when i rebuild the rails an the engine mounts
i can attach a battery cable to the steel engine rails then attach the zinc to the other end of the cable an put it down in the bilge an wait to see that happens it ez enough to do
worth giving it a try
 
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