Raw Water Intake Hoses from Genset and Engine Question

[Panamajames]

Both raw water hoses intake have 1 inch bubbles on the outside of the hoses in several places. Kohler generator has only 60 hours on it but is 5 years old. Should I replace the hoses. They are very thick and not sure why this is happening to the hoses. I am a little new to maintenance issues. Please tell me what you think. Thanks.

[James S]

I'd replace them.

[Panamajames]

The hoses look brand new except for the bubbles .. They are not very high bubbles nor very big 1" Not soft on bubbles either.. Thanks for reply.

What is causing this. Old age?

[James S]

Sounds like some surface delamination...are they distributed in such a way that they look like some solvent or something else was spilled on them…splatter pattern?
If the bubbles are thin skinned and not deep they may not be an immediate concern.
I would replace them in any case....I just wouldn’t want to have them in the back of my mind any time the valves were open...these are the things that sink boats at the dock.

[Panamajames]

Yes they are thin skinned.. They are just in certain places. Not alot but what is interesting is that the hose for engine and generator a close to each other.. The hose on genset is 60 hours old and 5 years. They both have the same rises on them.

Seacocks are closed as I am away from the boat for a week. Thanks for your help.

[James S]

Sure sounds like something may have been spilled on them.....any pics?

[GordMay]

A brain aneurysm is an abnormal bulge in a brain artery that develops where the blood vessel wall is weakened.
Visualize the artery as a water hose. If the rubber in a section of the hose becomes thinner, the hose will develop a balloon-like bulge at that point. While the hose may still work, water pressure could cause leaks in the stretched-out hose wall or even cause the hose to burst.
Similarly, a brain aneurysm may allow blood to leak into the subarachnoid space around the brain, causing damage to brain cells. The brain aneurysm also may rupture, causing a serious and perhaps fatal stroke.
Were it as cheap and easy to fix a brain aneurism, as it is to replace a water hose - would you?
Why not replace the substandard hose (anticipating a positive answer)?

[Solitude]

You will spend more time trying to find out why the have a bulge than replacing them. You'll sleep better at night too.

[Panamajames]

I will replace the hoses Thanks everyone... Good advice

[Panamajames]

The blister and rises on the genset and engine raw water intake hoses could be from ENGINE HEAT.. I noticed blower was not working properly so I opened engine room door and blew fan into it.. Previous owner may have let engine room get hot and THUS THE BLISTERS ON OUTSIDE OF HOSES.... What do you think please....The blower is squealing so I turned it off.. and opened door to put fresh air in.

[osirissail]

Definitely caused by heat. These are suction hoses, not pressurized hoses. Anything heating the hose excessively will cause blisters. Re-route the new hoses away from heat sources. If a heat blisters degrades the wall of the hose, it might allow air to be sucked into the hose and result in insufficient cooling water getting to the engine/genset.

[James S]

I wonder if this was caused by high heat...what other damage or degradation may have occurred in other areas....seems like that’s a lot of heat!

[Panamajames]

I just got the boat several weeks ago and have 20 hours on the engine since.. I realize now after all this discussion since they are not pressure hoses they are heat blisters. Not terrible high or wide 1 inch. I will wrap with heat resistant tape and fix the blower. The previous owner neglected this I realize now.
And myself for 20 except I opened the engine room door and blew air with a large fan in while I was motoring .

The comments everyone made helped me figure this out.. I appreciate everyones help very much.....

I bought the boat fully loaded at a very good price so I did my own amateur survey.. I knew I would run into a few things like. I like to understand things fully so this is an adventure for me.

[James S]

I'm a little bit confused...is this a water cooled engine?

If so I'm surprised there would be a fan necessary to cool the engine compartment sufficiently to stop blisters from forming....am I missing something?

[Panamajames]

Let me explain.. The blower in the engine compartment died on me , at least it was squealing like a stuck pig so I turned it off.. I simply opened the door and used the fun to prop open the door so it would not swing. Then I decided why not turn on the fan and blow out hot air. I did not do that for the hoses just general cooling.. Yes water cooled. Probably does not do anything but heat up the cabin but it keeps my back bedroom a little cooler. Just a temp thing due to fact blower either needs come WD or replace the bearings or the whole thing.

Water cooled Yanmar, yes sir Regards James