Upsizing raw water engine SeaCock, Strainer, White Steam Smoke

[Blitz]

Maine Sail,
My project is part of upsizing the internal strainer from a plastic 3/4" Sherwood strainer to a Groco ARG 1000 (1") for an Yanmar 3GM raw water cooled engine (I think you recommended this Groco Strainer somewhere). With this, I was thinking I should up-size the Sea Cock to at least one inch, but it seems on your Winterizing video your engine Sea cock may be much larger - but then again you have a totally different engine.

I'd like to stick with Marelon since that is what I've had for over 30 years on my boat without any issues and trying not to add additional metals below the waterline if I can.

I was curious, if you have ever tested the MF 849 Marelon valve which is the one with the flange? (I have a MF 849 currently at 3/4" but that makes the Marelon Thru-hull at .660" ID)

Do you also recommend upsizing engine raw water intakes from 3/4" to 1" in the OEM 93 series or should I go larger? It should be noted that I have a Raritan 6 Gallon Hot Water Heater with 3/4" NPT without any diverter valve for heat exchanger water.
I do get a little bit of white steam exhaust when running at 2,800 RPMs.

Thanks for your help, testing and suggestions.

 

[jssailem]

@Blitz you can save $50 to $125 and get the 750 . 3/4 inch hoses.
Plenty of water for your engine. Get the full flow 90 degree fitting.

 

[Blitz]

Thanks - I was planning on the full flow fitting for the flow into the internal strainer, but after the strainer it has to be stepped down due to the tiny piping on the engine's raw water cooling water pump.

 

[jssailem]

Neal "Tiny Piping"? What engine are your running?
The concern is can your water pump draw water in through the strainer. Too big of a strainer and your pump can not get it filled let alone draw it to the engine.

 

[Blitz]

Neal "Tiny Piping"? What engine are your running?
The concern is can your water pump draw water in through the strainer. Too big of a strainer and your pump can not get it filled let alone draw it to the engine.

Yanmar 3GMD which is raw water only - see original post

Bigger strainer would be no different than drawing out of a bucket, it can easily draw it to the engine.

I'm going by memory since not at boat but I think the hose attaching to the sea water pump is like 5/8", which means it's much smaller inside diameter going into the pump.
Also, any white smoke which is most likely steam is minor and only when pushed at high rpms.

 

[Blitz]

@Blitz you can save $50 to $125 and get the 750 . 3/4 inch hoses.
Plenty of water for your engine. Get the full flow 90 degree fitting.

I know this is old, but thought I should note: The odd thing is that if I use a 3/4" Groco Strainer such as their ARG-755-S or ARG-750-S there is no Groco full flow 90 degree fitting with 3/4" NPT for 3/4" hoses. Seems odd.

Full Flow NPT Bronze Hose Barb | GROCO

GROCO Full Flow NPT Bronze Hose Barb Fitting.

www.groco.net

 

[jssailem]

Oh. You want a 3/4 Hose ID.
Well you are correct.
I am not sure but I would hazard a guess. It has to do with the thickness of the bronze needed to support the 3/4 threaded part and the strength for the 90 full flow turn.

 

[genkinyc]

I had the same issue when re-powering my boat recently. I put the original and beautiful bronze groco arg-500 strainer to one side, and purchased a smaller and much lighter Vetus plastic strainer.
I'm very happy with it, because it's smaller, lighter and easier to fit without adding all the additional piping bends, and it solved my issue, allowing an upsize of pipe diameter into the engine.

Might work for you, take a look here.

Strainers

Strainers

www.vetusmarine.com