how to get antifreeze thru wuthout an internal strainer?

[33ec]

Good morning. I recently purchased a new to me boat with a pair of detroit diesels. fresh water cooled with dry turbo's . This boat has barnegat style scoop strainers on the outside of the hull and no internal strainer for the raw water pump prior to the heat exchangers. it has 3" intake lines and not a lot of flexible pipe after the thru hull valve. My challenge is how to get the anti freeze thru the raw water side. I was thinking about simply removing the zinc from the trans cooler and hooking a bucket of antifreeze to that opening while cranking the engine to allow it to be pulled thru but this is only a 3/8" opening. I am concerned about damaging the inpellar due to low flow. I would also be able to hook up an air line to blow it out but am unsure if that would get all of the water. Does anyone else have a similar set up and if so, how do you winterize the drive engine raw water system? Large internal strainers are quite expensive and I really don't need them with the type of external scoops I have in addition to adding another large item to the engine room, Ii would rather not add them.

Doug

 

[alnav]

Doug, on my Cummins engine, the prescribed procedure is actually not to run the antifreeze through by running the engine even though I expect most, including me, do it that way. The book procedure is to drain the coolant by taking out the zincs, remove the raw water impeller and pour antifreeze into the topmost raw water hose on the engine that goes into the heat exchanger thereby filling the raw water system. I would think a similar procedure might work in your case but you'd want to plot out the raw water system carefully to make sure you can drain from the lowest point and are getting antifreeze everywhere it needs to be.

 

[rondds]

What about using a length of hose from the bucket to the tranny cooler that is a greater diameter? Pick up a larger diameter non-collapsable length of hose (west marine) and get it set up with larger diameter stuff all down the line? You can use PVC valves (instead of hose type gate valves).

Our buddy Dominic (ODS9) used to use a big rubbermaid storage container filled with pink for his Cat 3126s. He attached a valve to it like this one to the container...

and connected the appropriate diameter hose to the output side. Not sure what hose he used. There's this stuff, available at Home Depot (for sump pumps) but I'm not sure if it will withstand the suction created by the impeller...

 

[quality time]

I winterize a 56' Ocean with no strainers. We have barely enough hose to stick in a bucket after removing from the thru hulls. Could you buy a longer piece of 3" hose to temporarily connect to the engines?

 

[33ec]

thanks for the feedback. good suggestions. I do use a larger hose on the bucket of anti-freeze but the limiting factor is the zinc size. I have 1/2" zincs as well but on the wrong side of the rw pump. I like the idea of removing the hose prior to where the raw water enters the exhaust just past the turbo high up in the ER . this might work since my turgos are dry and my set up does not discharge throu a 'strainer' type fitting from the exhaust manifold into the exhaust system. there is a siply 1 1/2" hose that directly bypasses the turbo and goes from the maifold to the exhaust pipe. letting gravity drain the anit-freeze back down to the trans cooler at the lowest point might work and be pretty easy to do.. I am not too concerned about a little raw water in the mufflers as they are about 15" diameter and look like cherry bomb mufflers from an old 1970 dodge I once owned. thanks agin for the suggestions.

 

[Alex F]

I personally would consider two options:

1. Add the seastrainers. This would be a great long term solution. I honestly don't understand why would a yacht of your size be missing them. But, after seeing strainer after the impeller pump I'm not surpised.

2. If for some reason #1 is not working for you, at least this year, then I would use Al's suggestion. I did it this way on my 1st SR. It was fine the following spring, so the procedure works.