Cracks in coolant hose

[Irish Rambler]

I'm sorry if I sound confrontational but why all this mental masturbation ?
Hoses should be throroughly checked in spring and autumn and it should be a part of your automatic check list every time you do your engine checks.
As regards losing coolant when you change hoses or drain the system, you've got a boat worth thousands of dollars and your whingeing about putting valves on because you might lose a few dollars worth of coolant ?
You don't need to over complicate the issue by fitting valves you simply need to concentrate on doing your maintainence checks thoroughly. K.I.S.S
You should also bear in mind that coolant contains a lubricant and cleaner which keeps your main engine water pump lubricated and coolant galleries clear, changing it periodically is also part of your maintainence.
I'll probably now get banned from TF for plain speaking.

 

[dhays]

I'm sorry if I sound confrontational but why all this mental masturbation ?

That is just how I roll I'm afraid.

Hoses should be throroughly checked in spring and autumn and it should be a part of your automatic check list every time you do your engine checks.

I think your approach to inspection and maintenance is admirable and something that I should try emulating.

As regards losing coolant when you change hoses or drain the system, you've got a boat worth thousands of dollars and your whingeing about putting valves on because you might lose a few dollars worth of coolant ?
You don't need to over complicate the issue by fitting valves you simply need to concentrate on doing your maintainence checks thoroughly. K.I.S.S

I don't believe I was complaining about the cost of replacing coolant but maybe I did? My motivation for adding valves on the heater coolant circuit wasn't cost but safety and convenience.

You should also bear in mind that coolant contains a lubricant and cleaner which keeps your main engine water pump lubricated and coolant galleries clear, changing it periodically is also part of your maintainence.

That is also an excellent point.

 

[SteveK]

Installing valves will only provide a means of servicing the hoses and isolate the engine during servicing.

Any indicator of a leakage will have occured before you have a chance to turn off the taps.

Irrigation companies use air to flush lines of water. If you were to replace the 30 feet of lines I would consider that setup to reclaim most of the coolant. Or a shop wet vac .

Replacing all the hose is your decision to make. So far what you have shown I would not be ready to replace all hose. The only picture you have shown is one location of cracking where the hose is attached and bent, to me that is to be expected as a stress point, but that alone does not warrant a complete change out. I would have to see all hose termination points and along any runs showing more cracks.

The only repair I would do with available information is to cut off about a foot of hose, install a valve to connect the new hose section. Do the same with the return as that must also be a stressed connection point in the hose. mostly straight runs with no age cracking are still functional. IMO

 

[Irish Rambler]

Apologies for being abrupt.
Determine the cause of the problem and modify it if necessary.
Record all details in your boats maintainence file.
Job done.

 

[dhays]

Replacing all the hose is your decision to make. So far what you have shown I would not be ready to replace all hose. The only picture you have shown is one location of cracking where the hose is attached and bent, to me that is to be expected as a stress point, but that alone does not warrant a complete change out. I would have to see all hose termination points and along any runs showing more cracks.

The only repair I would do with available information is to cut off about a foot of hose, install a valve to connect the new hose section. Do the same with the return as that must also be a stressed connection point in the hose. mostly straight runs with no age cracking are still functional. IMO

That is an idea. The reason for my urgency is that the one hose in particular I think has been weeping coolant. It wouldn't surprise me if most of the hose is just fine. There are places where they do look very bad, both at points where they bend.

Unfortunately, most of the hose is not very accessible. This makes it very hard to inspect. My thought was that by the time I daylighted all of the hose I would have done 75% of the work needed to replace them.

Still, your idea of simply replacing the bad sections has merit. The hoses make bends in three places, at both end of the hoses, and at one point where they make a 90 degree term. I may be able to more easily access that midway bend point and see what it looks like there. If it looks good, then simply replacing a couple worn sections may be an option to consider.

As always, you guys come through with alternative ideas that I wouldn't have considered.

 

[BruceK]

Often you can buy hose sections at auto shops to match existing. Doesn`t have to be an exact match. You can trim length etc to get the section you want. Sometimes you cut what you want out of a longer piece. Can save a lot of hassle getting OEM stuff which is no better.

 

[dhays]

Update:

So I decided to use some valves. Today I drained the existing coolant into two 5 gallon buckets and sealed them. I plan on reusing the coolant. I had about 1 cup of wasted coolent in the process and about 1/2 cup that spilled and I had to wipe up with shop towels. All in all, not too bad. I used a hand pump to get out about 3 gallons from the upper reservoir into a bucket. Then used the drain plug on the coolant collection tube to drain most of the rest using a Poly hose into a bucket sitting in the bilge.

I used a 45 degree Brass street elbow on the engine and a SS mini valve connected to that. The biggest challenge is getting a directional fitting like an elbow to end up pointing in the right direction. I used the same combination on the return connection into the coolant collection tube.

As soon as I even bumped the cracked hose in the original picture, it started to leak fluid. So I discovered this problem not a moment too soon.

Ran out of time so tomorrow I'll refill the engine with coolant and then run the engine and check for leaks. It is tight, then the next step will be trying to inspect the rest of the hose. I may be able to get away with just replacing either end of both hoses.

 

[luna]

Update:

I used a 45 degree Brass street elbow on the engine and a SS mini valve connected to that. The biggest challenge is getting a directional fitting like an elbow to end up pointing in the right direction. I used the same combination on the return connection into the coolant collection tube.

As soon as I even bumped the cracked hose in the original picture, it started to leak fluid. So I discovered this problem not a moment too soon.

Ran out of time so tomorrow I'll refill the engine with coolant and then run the engine and check for leaks. It is tight, then the next step will be trying to inspect the rest of the hose. I may be able to get away with just replacing either end of both hoses.

I suspect that mounting the valve on a Brass 45 degree street elbow is a mistake as brass is very weak and has no business supporting the weight of a valve and the hose, in a cantilever condition on a rattling diesel engine.

I would replace the brass with the strongest steel fitting I could find, likely from a hydraulic shop.

C lectric in post #12 has mentioned his experience with the same thing.

You should also expect an increase in the time to heat the water tank due to the reduction in the coolant flow as a result of the mini valve. A full port valve of the proper size fixes this problem but results in more mass rattling around on the end of the 45.
If it was me, I’d mount the full port valve on the floor and run new quality hose everywhere.

 

[dhays]

I suspect that mounting the valve on a Brass 45 degree street elbow is a mistake as brass is very weak and has no business supporting the weight of a valve and the hose, in a cantilever condition on a rattling diesel engine.

Yup, definitely a possibility. I will see what happens.

 

[Comodave]

What will happen is the brass will fatigue and break. That is why I recommended no valves. If I were to put valves in I would use a short piece of hose and then the valve and then the rest of the hose. If you are going to leave the valves connected directly to the engine then use a steel fitting. If doing a short piece of hose to the engine then secure the weight of the valve to something strong off the engine so it won’t be flopping around.

 

[twistedtree]

If the ends are cracked all the way through, then I would definitely replace all the hose.

 

[RT Firefly]

Greetings,
Mr. C. I too would be worried about mounting a valve directly to the engine and agree that IF valve(s) are used, they should be remotely hard fastened with a rubber hose inter-connection (My post #27).

 

[dhays]

I think the concern is warranted, but I've seen examples of Tony Athens using these same street elbows on engines for the same application.

 

[luna]

With all due respect to Tony Athens, does Cummins, Yanmar, Volvo, or anybody else use brass fittings wound into the block/head, and connected to and supporting a valve and hose?
Cat as far as I know does not, everything is steel.

 

[Flatswing]

i replaced mine with silicon heater hose & good quality SS valves (with safety locking handle) in line adjacent to stringers so no vibration. Really no reason not to be able to isolate the water heater coolant circuit.
I save the bags from Bota Box wine (seems I have quite a few!) The bags are double thickness food grade heavy plastic. One can pry the valve out carefully with a large screwdriver then they can be easily refilled with old oil, antifreeze, etc. then push the valve back in and they seal perfectly. I keep a dozen or so on board for changes or emergencies while cruising as they take up no space when empty.

If you want to dispose of antifreeze, typically any municipal transfer station/ landfill will take for free - same section as old paint, used oil etc.

 

[dhays]

I save the bags from Bota Box wine (seems I have quite a few!) The bags are double thickness food grade heavy plastic. One can pry the valve out carefully with a large screwdriver then they can be easily refilled with old oil, antifreeze, etc. then push the valve back in and they seal perfectly. I keep a dozen or so on board for changes or emergencies while cruising as they take up no space when empty.

That is a great idea.

If you want to dispose of antifreeze, typically any municipal transfer station/ landfill will take for free - same section as old paint, used oil etc.

I reused the coolant. I did a test of the coolant and it was in pretty good shape but I will add a point of Fleetguard's DCA4 to adjust it a bit.

 

[Hobbit]

If you add valves make sure all fittings and valves are stainless. Use a shopvac to catch the flow when changing lines. Also use better quality hose. IMHO

 

[Comodave]

Advertising bot, no need to reply.

Could well be. We can let the mods check it out.

 

[SteveK]

Could well be. We can let the mods check it out.

I count 5 posts so far all pushing a source for clamps without any other input.

 

[Irish Rambler]

I'd like to make 2 points. 1, is that during this discussion nobody mentioned cleaning the coolant system with radiator/engine cleaner after re installing the valves and hoses and before refilling the system with coolant.
Whenever we do any work on the cooling system it's standard practice to maintain the system in pwo, or, if no faults every 5 years as part of our preventive maintainence schedule.
2, I would never, ever, use clamps for the simple reason that everytime you use one ,some of the little micro fibres that re-enforce the hose wall will be broken and over time these lead to a weak point in the hose wall.
Why risk the ship for a ha'porth of tar ?
You paid thousands for your ship so why quibble over a couple of hundred to keep it in top condition.