Raw water hoses/garden hose connection

I was working on putting a garden hose connection on my raw water intake last night and discovered that my cooling hoses are in really bad shape (on the inside).   I also seem to have an assortment of types of hose.   I'd like to replace the hoses, and add the garden hose connection, but would like to know what type of hose to use, and why?    I am guessing that the wire reinforced hose is the stuff to get so that the suction from the rwp does not colapse the hose?

For my original garden hose Idea, I put a brass tee in the thru-hull to strainer line, but this seems really cumbersome with having to remove the doghouse and floor section to access.    How have you guys done the cold water connection?

Pardon the foolish question - is there a check valve somewhere, if not why doesn't the hose water just flow out the raw water pickup?

I was wondering the same, but I guess once the engine is running the pump will suck all water....

Oh, and if you want reinforced water line hose with a blue stripe to match your boat, check out Jamestown Distributors. Most other places sell hose with a green stripe.

With the exception of the circ pump to stat housing hose, a PCM 351w uses 1" hose throughout. Jamestown sells sticks of 12.5' in addition to 50'... call and they may sell it by the foot as well.

63 Skier wrote:     Aha, thanks! I wouldn't have expected that to work, too easy for the water to drop and pump to suck air, learn something new every day. On my '63 I disconnect a hose and clamp the water hose in the end, have to be careful to turn the water on and start up at the same time.

Not much water is needed in the driveway!!! BTW, if you do use a check valve, be REAL careful on it's CV rating. It's real easy to screw things up on the suction side of the RWP.

CV:
"Cv Factor— Coefficient of volume. Amount of liquid in gallons per minute (at 60° F, specific gravity of 1) that passes through a fully-open valve with a 1 psi pressure differential. Higher Cv factor means a higher flow rate."

dont forget that even with a reenforced wire hose the outside faucet might only deliver 5 or 6 gal per minute at best you might still starve the motor

I have no idea whats needed but my house delivers decent street water pressure and volume and when my boat is running on it at 2200 or so ive seen my black rubber hoses flatten out . im sure that your right that it is fine at idle and just above and there is no need to run them at 4k in the driveway . i was just asking him to be aware of the issues that someone could run into. if i remember correctly this has been addressed in a previous thread where i was made more aware of the issue

You might also want to try

surplusunlimited.com - sells by the foot at about 1/2 of West Marine
discountmarinesupplies.com - sells by the box

Thanks fibersport.   I will check Skidim and surplus unlimited.   I think I have it rigged ok to do my winterizing now, but will want to put in new hose once the stringers are done and the engine is cleaned up.   I'd like to run on the hose long enough to troubleshoot the lack of Idle issue that I am having currently also.

Dreaming wrote: anybody know how many BTUH the engine produces at idle?   that might give us the answer to 63's question...

Gasoline has 114,000 btu/gallon. I don't know the fuel burn at idle, maybe 2 gal/hr.? If you know the fuel burn, you know how many btu produced if you assume all the fuel is combusted.

But - I'm not sure it matters in this case. It's pretty hard to overheat a raw water cooled engine even if water flow is reduced, as long as all passages are getting some flow. That's why I ask if there is any mechanical issue with the low water flow, I've always assumed it was fine if there was decent flow from both manifolds.

peter1234 wrote: I have no idea whats needed but my house delivers decent street water pressure and volume and when my boat is running on it at 2200 or so ive seen my black rubber hoses flatten out .

Thats one reason why a simple tee in the line works so well. Any volume of water that the RWP calls for beyond what the hose can supply will be made up by the air from the intake grate/scoop. Thats a better situation than collapsing a hose, which could cut the water supply off completely.

63 Skier wrote: What is the concern on running less water flow? As long as there is some water flow, and flow out of the exhaust pipe or pipes, it should be enough to keep things cool for warmup before oil change, winterizing, or other. Am I wrong, is there something that might be harmed if the engine flows 4 gal./minute instead of the 7-8 it might flow when in the lake?

Youre exactly right- there is no concern with pulling less water through the engine when on the hose. So long as you draw enough in to 1)keep the engine cool and 2)lubricate the impeller, youre golden.

The bucket method works great if youre trying to test your RWP, but for simple running on the hose, it sure seems like a clunky way to do things.

I still have never been able to use the T that came installed on my SAN. My only guess is that the RWP cannot overcome gravity in the 6 inches or straight vertical prior to the strainer. I even blocked the intake grate once to no avail. I just take the hose off after the strainer as Greg described and run off the hose. My impeller test comes free with the bucket of RV A/F after running for a while on the hose.

I am extremely lame in that I have already winterized the SAN. I got eleven whopping hours on my boat this year. Most of the lakes around us are just coming off "no wake" this week from the high water this year. The Pony has been on a trailer since June....

Ok...I'm digging this one up...

Someone said that the hose for a PCM 351 is 1" (except for one hose). This may be a silly question, but is that inner diameter or outer? West Marine lists both sizes...