Do you flush your heat exchanger?

[rondds]

Yes, boiler valves! I'd prefer ball valves. Someday. All the other parts are bronze. Brass is probably not the best for salt water applications (dissimilar metals in an electrolytic environment). Still another reason to climb in the bilge, work the seacocks and take it all in at least once a week.

Man you've got a TON of room btwn those engines! How's that? What's the beam on your boat? I'm 12.5" and can barely get my forearm btwn the risers!

BTW, with all the restrictions, the flow from the exhaust is visually the same as when pumping seawater. I do not rev the engines at all. Run at dead idle speed for about 3-4 minutes.

 

[sprink56]

Yes...she's a "fat bottom girl"....14'...:thumbsup:. I have a neighbor 2 slips down with a 2006 38 'dancer who came aboard and couldn't believe the difference between his and mine. His beam is 12'-6"...he told me that in the new ones you have to get to a 43' 'dancer to get a 14' beam.

Speaking of di-electric...you don't have that much going on that a little teflon tape & pipe dope won't handle.:thumbsup:

 

[Nehalennia]

I like it in principal. The only thing that I am even slightly dubious about is the frictional loss across the check valve. This thing is not full port and will restrict the raw water flow.

When we test back flow preventers in fire and plumbing supply lines we use a differential pressure gage. As time go's by these things are bound to become crudded up in as much as the baskets in the strainers do. We usually end up taking back flow devices apart and servicing them annually. If this rig has no way to be serviced/cleaned I wouldn't trust it.

They're $80ea. Just replace them every year or two. Seems simple enough.

 

[rondds]

Speaking of di-electric...you don't have that much going on that a little teflon tape & pipe dope won't handle

That's precisely what I thought at the time of install. I didn't use any dope, only teflon tape.

14' - that's a BEAST! Man, I wish. The mid'90s vintage 370 'dancers have 12.5' but you can stand btwn the motors.

 

[sprink56]

They're $80ea. Just replace them every year or two. Seems simple enough.

I hear you but remember in my case "your" year or two is 8~10 months for me...way down here at 26 deg N. Lat. we do boating 12 months.:thumbsup:

 

[rondds]

Sprink
Did you ever get those numbers from Sherwood?

 

[wileecoyote]

Yes, boiler valves! I'd prefer ball valves. Someday. All the other parts are bronze. Brass is probably not the best for salt water applications (dissimilar metals in an electrolytic environment). Still another reason to climb in the bilge, work the seacocks and take it all in at least once a week.

Man you've got a TON of room btwn those engines! How's that? What's the beam on your boat? I'm 12.5" and can barely get my forearm btwn the risers!

BTW, with all the restrictions, the flow from the exhaust is visually the same as when pumping seawater. I do not rev the engines at all. Run at dead idle speed for about 3-4 minutes.

You arn't kidding about the room. I was thinking the same thing when I looked at the pic. You could put another cabin in that room. Like Ron said, your arm will barely fit between the manifolds on our "little" boats! ( mines not quite 12') Hanging upside down I can barely touch the forward bilge pump, trust me I know! :smt021Taking out the batteries is another adventure.:smt089 Nice compartment you have there Sprink!

 

[sprink56]

Sprink
Did you ever get those numbers from Sherwood?

Yes...30 GPM for most big block Chevy's. Some of the HP/Racing applications are a bit higher. The impellers are delivering the volume logarithmically... as the RPM increases so does the GPM up to the rated capacity which is about 30 GPM.

The tech people at MPI say that in real world applications that they can run a 7.4 or a 8.1 up to about 2000 GPM before the raw water pump starts to implode a 5/8" garden hose. Given that, running 1: 7.4/8.1 on city water through a garden hose at idle would in my opinion be pulling almost 100% fresh water with the seacock open.
Any thing above idle would begin to pull raw water into the mix.

 

[sprink56]

You arn't kidding about the room. I was thinking the same thing when I looked at the pic. You could put another cabin in that room. Like Ron said, your arm will barely fit between the manifolds on our "little" boats! ( mines not quite 12') Hanging upside down I can barely touch the forward bilge pump, trust me I know! :smt021Taking out the batteries is another adventure.:smt089 Nice compartment you have there Sprink!

I guess I better start checking for stow-aways.:thumbsup:

 

[rondds]

Sprink
Thanks - that's great info. I'm not so concerned about the raw water pickup b/c my seacocks are closed, but it's nice to know that the impellers are not being starved for water. The orefice on the boiler valve is certainly not 5/8" and the washing machine hose is (I think) closer to 1/2". But I'm not getting over 700rpm anyway so by my guesswork, I'm doing fine.

Thanks again!

 

[Asureyez]

The short answer is yes we salt water boaters have to flush (De-Scale) our Raw water cooling systems in the mains, the genny and the A/C units at least once a year.

Flushing with fresh water after every use, with aboat that's in the water, nah thats for whimps!

I take a week end day during the winter and de scale the lot, it takes all day, not hard work just time for the chemicals to work. OH, well getting to that damn Starboard raw water pump is another story, but later on that.

Year round keep the zincs changed, bond wires tight and enjoy boating. One Day a year clean the cooling systems.

If anyone needs a step by step on how to do this let me know and I'll write it out for a Cummings CTA .... also for A/Cs if needed.

Here is the juice I use in Concentrate form, Jim can probably get it for you, it's about $75 bucks a gal here:

http://trac-online.com/pdf/TDS-Barnacle_Buster.pdf

http://trac-online.com/pdf/TDS-Barnacle_Buster.pdf

 

[Alex F]

Given that, running 1: 7.4/8.1 on city water through a garden hose at idle would in my opinion be pulling almost 100% fresh water with the seacock open.
Any thing above idle would begin to pull raw water into the mix.

sprink56,
Thanks for the info, this is great news. This is important for me b/c I'm leaving my seacocks open.

 

[Hoo'sdave]

Have you guys seen these?It's a Perko Flush Pro The link describes how it works
I've heard good and bad but have not purchased one myself, I'm able to flush out my heat exchanger through the Muffs.

I install 2 on by boat yesterday.Tested after we had been out in the afternoon.I think that work just fine.$82 each warranty for 5 years

 

[Chris R]

The short answer is yes we salt water boaters have to flush (De-Scale) our Raw water cooling systems in the mains, the genny and the A/C units at least once a year.

Flushing with fresh water after every use, with aboat that's in the water, nah thats for whimps!

I take a week end day during the winter and de scale the lot, it takes all day, not hard work just time for the chemicals to work. OH, well getting to that damn Starboard raw water pump is another story, but later on that.

Year round keep the zincs changed, bond wires tight and enjoy boating. One Day a year clean the cooling systems.

If anyone needs a step by step on how to do this let me know and I'll write it out for a Cummings CTA .... also for A/Cs if needed.

Here is the juice I use in Concentrate form, Jim can probably get it for you, it's about $75 bucks a gal here:

http://trac-online.com/pdf/TDS-Barnacle_Buster.pdf

http://trac-online.com/pdf/TDS-Barnacle_Buster.pdf

Can you give me a quick lesson on "how" you use this stuff? I've looked and can't find anything. I don't want to invest the money in the product if it's going to be a logistical dead end.