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'91 430/DP-c raw water inlet hose type

M

motorheadted

New member
Hello all; this is my first post on this forum, so please bear with me as I don't know all the proper terms for some parts.
The raw water intake from the o/d comes in thru the transom plate on the port side as a 1.5" hose nipple. Ahose is connected there, and runs fwd to the input of the pwr steering oil cooler. From the cooler, another hose (factory molded heavy wall) continues fwd to the raw water pump inlet.
At some time in the past, I had replaced the aft hose with some stock heavy wall, wire inbedded water hose. After that I installed a "T" in that hose for a neutra-salt feed. Now I want to install another "T" in the same hose for a engine flush input, but with that addition, the hose will no longer make the required bend necessary to connect to the rear nipple. so.
was this hose originally a factory molded one, like the front part? ( I've been to 3 different dealers, and this hose does not exsist in their parts books)
Is there another type of hose the will work in a suction enviroment, but is more flexible ??

Ted
 
Ayuh,.... Ribbed or corrugated wire reinforced hose bends easier than solid straight walled wire reinforced hose,....

Probably available at most auto parts stores,...

38417-7370615.jpg
 
A flushing "t" should have 2 valves, one inline to stop flow from drive, the other to allow flow from the flusher hose. I use a red brass hose bib installed in a reducer for the flush hose. I'd like a bronze one, but can't find one, so I replace the brass hose bib every 3 to 5 seasons. This allows a short section of garden hose to a bucket for flushing. NEVER hook the raw water inlet directly to a pressure source, i.e. directly to the hose. Always use a 3 to 5 gallon bucket with the water source hose running freely into the bucket and a hose to the engine to draw water as it wants. My 5.7L FWC MERC draws water at idle slower than the hose source feed @ 650 idle, but at any RPM much above that the engine draws more water than the dockside feed can supply. This of course, is just my situation, your situation may vary. I flush my engine (actually just the HE and elbows) ever couple of trips and use Saltaway a couple of times a season and at winterizing time. For my setup, 2 1/2 gal of antifreeze winterizes my system ( raw water pump, H/E, elbows and mufflers)....the other 1/2 gal gets dumped into the bilge after I get it dry.
 
Ted, I’d suggest using an OEM hose.
The Volvo Penta seawater pump is engine mounted! Anything upstream from this pump is “suction”!
The automotive corigated hose will not be collapse proof against suction!


Also, I would not install any type of diverter valving that could become restrictive to the seawater suction path!


.
 
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+DAXX !!! Just typed a looooooooooong response and lost it due to timing-out on this site!!! Got some new hardwall water hose and that went on. Still wont flush with muffs, can't find a decent "T" to install in aft hose. VP factory hose obsolete, not available. Bummer!!!!!!!!!!!!!
 
Bob: before we moved 2.5 yrs ago, we were on a canal, boat was on a lift. I installed the Neutra-salt system and used that at the end of each run. If ,for some reason, I needed to run the engine, I just dropped the boat far enough into the water so the water inlet was submerged.
At our new house (not waterfront) the boat is on a trailer, hence the need for a different method of flushing/running the engine. The muff method would be the simplest way to go.
 
Ted, have you inspected the aluminum water neck fitting?
These are a wear item and need to be replaced routinely.
NOTE: some C drive water neck fittings are plastic!

With the boat on the trailer, you should only need the garden hose muffs!




.
 
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Rick: re; water neck fitting, I have not yet removed it. I had previously replaced it when I first got the boat. I had reversed-flushed the suction line at the pump input connection last week, and got tons of water out of the drive water inlet ports, also a couple of small geckos !! I tried the muffs again a couple of days ago, with various rube goldburg straps, etc to try to minimize water escaping from around the muff cups. Still had too much water escaping to my liking. Had engine running, but after about one minuet , had no water at pump. so I shut it down.
 
FWIF.... after having my engine overheat briefly when a plastic bag wrapped itself over the gill one one of my previous boats, I converted that boat and my subsequent ones to thru hull water pickup. My current, most trouble free setup has an oversized wedge shaped scoop on the outside of the hull. I use the one with the removeable SS screen and the door that opens for cleaning. The inhull hardware consists of a SS 1/4 turn marine ball valve that is screwed directly onto the threaded thru hull fitting. The "T" is bronze. The hose bib valve is screwed into a 1 1/4" to 3/4" reducer. Both this part and the hose bib are not readily available to me in marine grade materials ans are replaced every 3 to 5 seasons. Flushing or winterizing makes use of a 3 or 5 gal bucket with a free running water hose and a 4 ft section of garden hose that screws onto the bib. The only thing to look out for is to be sure that the hose bib valve is TIGHTLY closed less you get a vacuum leak while running. A better solution would be to have a second 1/4 turn in series ( directly on the "T") with the hose bib and reducer. I had space issues so I didn't do that. My engine is a MERC and has the raw water pump belt driven on the bottom of the engine. If you were to do this on a Volvo with a direct drive pump, you would need to route the hose from the inlet aft to the transom and then around towards the front of the engine. You end up with a couple of feet more inlet hose than stock, but if you use marine grade suction rated (wire reinforced) hose, you won't have any hose issues. The raw water hose on my boat, as shown below, makes a gentle complete 180 degree bend around the side and back of the engine and then forward. This system or a minor variant of it have been used by me for over 45 boating seasons with no issues on various Volvo drives.
 

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Bob: Thanks for the info on the thru-hull water pickup. I may end-up doing that.

Rick: are you familiar with the old ('90s) trim & tilt system with the round digital gauge ? If so, I'll start another thread.

Ted
 
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