description/difficulty of FWC install?

[JonnyQuest]

Got some new photos of engine compartment

JQ - The bulkhead in front of the engine appears to preclude the crank mounted pump unless you are able to modify it. The rather large alternator isn't going to be happy sharing a belt. You may be a good candidate for an electric pump, either bulkhead or thru hull mounted. The good news is that you appear to have a space for a vertical exchanger. Let's see a few more pictures. Attached is picture of my salt water pump. Hanley

Got back to the boat today and shot more pics of the engine compartment to assess the feasibility of MMI belt driven FWC system or Indigo's electric pump FWC system. I shot a ton of pics so I will only post a link to them here. I'm thinking the electric pump system may be looking more appropriate here.

Link: http://gallery.me.com/thomasbaileyjr#100139

What do ya'll think?

Thanks again, JQ.

[ndutton]

JQ,

Please forgive me if I assume skills not in evidence but it seems to me the engine box could be extended forward a few inches quite easily. I believe the actual carpentry would take maybe a couple of hours. It would afford you all the room you would need at the flywheel end of the engine for an additional pump (required for FWC).

[Kelly]

FWC electrical pump

Here's a photo of a quick installation of an electrical pump in the fresh water side of a FWC circuit. It is located in a cockpit locker about 2-3 feet from the manifold at about the same height as the engine. One of the blue hoses runs to the header tank which is installed just on the other side of the locker box (plywood walls). I chose the Johnston pump used by Indigo in their FWC kit.

I have not run sea trials but am satisfied with dock trials thus far. The pump is currently wired through a dedicated circuit breaker on the main electrical panel before I eventually install it with current coming from the ignition circuit. For now, I have to manually flip on the switch to power the pump. I also continue to chase and replace smaller circuit plumbing fixtures in order to minimize overall resistance to flow.

[hanleyclifford]

JQ - Kelly has posted a nice picture of the bulkhead option for the antifreeze loop. You certainly have the room for it. I agree with Neil's comment about extending the panel in front of the engine forward. Then you could run your mechanical salt water pump right off the crank. At the risk of emptying the barracks I would suggest that two mechanical pumps are usually the best arrangement if you can fit them into the space and don't mind the additional cost (which is considerable). Hanley

[ndutton]

Kelly and others,

When installing an electric pump on the ignition circuit (totally logical) please consider the added amperage on the circuit. This could involve replacing the ignition wiring to a larger gauge wire and perhaps a higher rated ignition switch, fuse or breaker, etc.

Of course, size matters but motors can be a significant draw, especially at 12V.

In the electrical industry it's a code requirement that circuits are designed to carry a maximum of 80% of their rated capacity in amperage. So, if you have a circuit comprised of 20 amp components (12 gauge wire, 20 amp breaker) the maximum allowable design load on that circuit is 16 amps. It's a policy that results in a trouble free system.

[hanleyclifford]

Neil's comments about loads in ignition circuits call into question the continued use of standard keyed ignition switches. I have always been suspicious of them and most recently have done away with them on my boat. Also, a #14 wire just ain't gonna git it anymore what with the addition of electric fuel and water pumps. I have resorted to the equivalent of a #10 wire thru a bat handled switch to oil pressure switches, which I now carry as spares much like a fuse backup. A separate momentary button handles the starting circuit.

[ndutton]

Hanley mentions a component I hadn't considered and learning more about his system on this thread I should have remembered.

In his case - and perhaps others - most everything engine related goes through an oil pressure safety switch. The rated amperage of the switch is a factor too.

Since I don't think there's much choice regarding the amperage of oil pressure switches, if there's a need, a N.O. relay of sufficient ampacity is a solution.

[hanleyclifford]

Some numbers for oil pressure switches. NAPA # OP 6624, also 6620 and 6626. I have been carrying both fuel and water pumps as well as instruments and ignition on one of the above but after reading Neil's comment above I'm going to calculate the loads. Either a relay or multiple switches on the "oil pressure distribution block" may be in order.

[JonnyQuest]

JQ,

Please forgive me if I assume skills not in evidence but it seems to me the engine box could be extended forward a few inches quite easily. I believe the actual carpentry would take maybe a couple of hours. It would afford you all the room you would need at the flywheel end of the engine for an additional pump (required for FWC).

In theory, yes. But The Admiral flipped out when I consumed some of that space already when upgrading the battery system--doubled the size of the bottom step which pushed into her domain--the salon/galley/stateroom/guest quarters/basement/attic/etc...

I'm going to have to make do inside the existing confines of the engine compartment.

(Besides, I suck as a carpenter)

[JonnyQuest]

Here's a photo of a quick installation of an electrical pump in the fresh water side of a FWC circuit. It is located in a cockpit locker about 2-3 feet from the manifold at about the same height as the engine. One of the blue hoses runs to the header tank which is installed just on the other side of the locker box (plywood walls). I chose the Johnston pump used by Indigo in their FWC kit.

I have not run sea trials but am satisfied with dock trials thus far. The pump is currently wired through a dedicated circuit breaker on the main electrical panel before I eventually install it with current coming from the ignition circuit. For now, I have to manually flip on the switch to power the pump. I also continue to chase and replace smaller circuit plumbing fixtures in order to minimize overall resistance to flow.

Thanks for the photo here. is the pump oriented horizontally? I was assuming that it had to be vertical, but i am learning to never make assumptions.

The increased electrical load is a consideration, and I have a friend that is good with electrical who I can solicit to help me on-site. I do have a push-button starter switch, but need to check the wire gauge again--probably needs to be upgraded along with fusing.

how big is the header tank (got a photo?) and can it be placed in the locker box as well? What are the installation limitation for this? (if any)

Thanks again and Happy Thanksgiving to you all.

[hanleyclifford]

Ain't nobody happy unless...

That being the case you should focus on the electric options. If you choose the Indigo pump they want you to use it for the antifreeze side. If you choose the thru hull mounted baitwell pump like mine you can use your engine pump for the antifreeze. Either way you need exchanger and header tank. With your layout I recommend the combination from Moyer Marine or Indigo. I also recommend you eliminate as many angle fittings as possible. The electric pump should be on an oil pressure switch. You may be able to incorporate some features from my Engine album.

[hanleyclifford]

A header tank is nothing more than a pressurized reservoir with a cap for adding antifreeze. The hose from the neck under the cap goes to the overflow tank which also feeds the system as needed. Here is a picture of mine, but is probably not right for you. It seems you would do better with the exchanger/header tank unit.

[ndutton]

In theory, yes. But The Admiral flipped out when I consumed some of that space already when upgrading the battery system--doubled the size of the bottom step which pushed into her domain--the salon/galley/stateroom/guest quarters/basement/attic/etc...

I'm going to have to make do inside the existing confines of the engine compartment.

(Besides, I suck as a carpenter)

Two valid reasons and you have my admiration for listing them in the proper order.

Regarding a header tank, you may not need one other than the HX itself. The purpose of a separate header tank is to provide a fill point for the antifreeze that is at the highest point of the FWC system. Most heat exchangers - and ALL the HX's I've seen for the A4 - have an integral pressurized fill cap. The 2 instances I can think of where a separate, higher fill point is needed is when a water heater is installed and the hoses to and from are routed higher at some point than the HX, and the case where there's insufficient space above the HX to conveniently pour antifreeze into it. If neither of those situations apply there's no need for a separate header tank.

[Kelly]

Thanks for the photo here. is the pump oriented horizontally? I was assuming that it had to be vertical, but i am learning to never make assumptions.

The increased electrical load is a consideration, and I have a friend that is good with electrical who I can solicit to help me on-site. I do have a push-button starter switch, but need to check the wire gauge again--probably needs to be upgraded along with fusing.

how big is the header tank (got a photo?) and can it be placed in the locker box as well? What are the installation limitation for this? (if any)

You're welcome for the photo. I'm a huge fan of illustrating the descriptions!

The pump is oriented horizontally in accordance with the included instructions that you can find here. The manufacturer allows for both horizontal and vertical installation with a preference for upward-directed output flow.

I do not have a photo of my header tank but it resembles the one in Hanley's recent photo. The header tank would need to be the highest point in the circuit for obvious overflow considerations. And as a basic electrical, plumbing, sailing and life philosophy, I always try to keep the distances between fixed points to a minimum. Right-angles in the plumbing are to be avoided as well.

P.S. Neil: Ampacity?! Really?

[ndutton]

Neil: Ampacity?! Really?

Yeah Kelly, get me talkin 'tricity and I get in the zone. Guess I'm a product of my industry.