Installing hoses on barbed fitting

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WALSHIE

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Are there any tricks to installing 1-1/4" metal re-enforced rubber hoses used for raw water pickup on the engine?

I always struggle with this and since the strainer and heat ex-changer are below the engines, leverage is little to impossible to gain (brute strength).

Some suggestions I heard:
1) Dish washing liquid
2) Grease
3) Heat Gun
4) Heat Gun AND grease

What say you boaterEd experienced mechanics? Any pearls of wisdom on this subject?
 
When you say medal reinforced, I assume you mean a metal wire built into the hose.
If so, look at that wire as a spring. When you are holding a spring with each hand holding one end, if you twist the spring in one direction, the spring will expand in diameter. If you twist it in the other direction, it will contract.
With this in mind, twist the spring/hose onto the fitting and twist it in the direction that will expand the spring.
Heat and detergent will help as well. K-Y jelly may even be better.
 
In my opinion, no on the grease, no on the heat gun, yes on the dish soap. For those brutal sanitation hoses i used to heat up a jar full of water in the microwave, then submerge the hose end into the hot water for a minute or so. After thay usually slides right on
 
I try and stay away from lubricants that don't evaporate and get removed from the joint after install. That "OIL" will always be in the interface between the hose barb and the hose, it might comprimise the joint a little.
I have used the hot water method and K-Y as it is water based.
 
Dow DC-4 silicon lubricant. You can also get small amounts of it as "pure silicon grease" in the plumbing section of the hardware and home improvement stores. Also use it on your oil filter seals rather than engine oil (filter comes off easily) and pump impellers (gives lubrication on initial start will not wash away). Has no effect on rubbers and lubes really good.

http://www.aircraftspruce.com/catalog/cspages/dc4.php?clickkey=98808
 
Petroleum products may cause damage unless the hoses are rated for them. I have used dish soap. If you have room, hold the end of the hose in a bucket of warm water. That also helps. So while you're warming the hose, wipe the soap on the fitting with your other hand. Install the hose on the hardest end first.
 
Another thing, get a spare 1 1/4" hose union (on the cheap from a big box store) and use it first outside of the boat where it's more convenient just so the hose already has that initial expansion. Just throw it away or return when you're done with it.
 
The only rubber DC-4 will harm is silicon. Other rubbers are unaffected.
 
So why are the dimensions made so tight that everybody has these problems. They are designed for a clamp not a friction fit so there should be enough clearance for a slip fit. If they are designing it for a friction fit and everybody is defeating the friction with a lube why not just make it with less friction?
 
quote:
Originally posted by mdoherty

So why are the dimensions made so tight that everybody has these problems. They are designed for a clamp not a friction fit so there should be enough clearance for a slip fit. If they are designing it for a friction fit and everybody is defeating the friction with a lube why not just make it with less friction?

Click to expand...


Possibly partly because 3/4 of boaters almost never check tightness of ALL the hose clamps , so the tightness of the fitting in the hose allows some degree of backup safety margin. engine hoses permanently compress under the clamps and the clamps expand and contract with heat but can permanently stretch a bit , not to mention cheaper ones corrode and break.

And some clamps will not seal some hose applications if the fitting is not tight enough- Note the special Oetiker clamps or plastic ratchet clamps on outboards that seal fuel lines much better than conventional hose clamps.

To a go a degree farther , Aeroquip makes very tight barbed "Socketless" fittings of special one-way design to be used with their Socketless hose . No clamps needed once the barb is inserted , (though the couple Aeroquip blue Socketless hoses on my engines do have supposedly superfluous hose clamps over them for extra peace of mind due to overly conventional frame of mind.)

Here's what they look like:

http://aeroquipperformance.com/i-16532234-fce1512-aqp-socketless-fitting.html

http://aeroquipperformance.com/p-24060-hoses.html ( scroll down to Socketless Hose)
 
I tried and failed!

Simply unbelievable how difficult this task is! One connection would not go in, poor leverage of course. I need to re-visit. I was using a heat gun and grease but still no joy....but I'll get it, eventually!!
 
quote:
Originally posted by WALSHIE

I tried and failed!

Simply unbelievable how difficult this task is! One connection would not go in, poor leverage of course. I need to re-visit. I was using a heat gun and grease but still no joy....but I'll get it, eventually!!

Click to expand...


Sure the hose is the correct size? Not saying you made a mistake....just saying QA/QC on a LOT of stuff these days is lacking. A 1/32 to 1/16 of an inch will make a world of difference in a tight fit.
 
If you use the right hose nipples on the strainer you can eliminate this problem. Forespar nipples and the ones made by either Perko or Groco, I can't remember which off the top of my head, are sized correctly to allow the hose to slide on easily.
 
quote:
Originally posted by Stephen

Petroleum products may cause damage unless the hoses are rated for them. I have used dish soap. If you have room, hold the end of the hose in a bucket of warm water. That also helps. So while you're warming the hose, wipe the soap on the fitting with your other hand. Install the hose on the hardest end first.

Click to expand...


Murphy's oil soap is not petroleum base, I used it for years when installing 3/8 water lines on mainframe power supplies (there were a lot of them). We used the paste based product. I still us it working around cars on radiator & heater hoses.
http://en.wikipedia.org/wiki/Murphy_Oil_Soap

Ken
 
If you use the right hose nipples on the strainer you can eliminate this problem. Forespar nipples and the ones made by either Perko or Groco, I can't remember which off the top of my head, are sized correctly to allow the hose to slide on easily.
 
Went for round two and was victorious.

Key was....leverage! In the end, anything that's not "fixed", and/or I couldn't get a really good grip with BOTH hands, I had to remove and do on the bench (not really, I was on the boat). The hoses that went to the through hull and the engine could be pushed on (With lubricant) since they were "fixed" and I could do hanging upside down with one hand.

The good news is, I made secure connections, added new double clamps on everything and no longer have to remove these hoses as an annual chore to winterize...instead, I added a "tee" with a hose bib fitting. I was able to easily test the engines with turning a couple of valves....MUCH better.
 
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