Help (re)installing heater

[Jordan22]

So, the previous owner removed the heater in favor of placing a large subwoofer in the driver's footwell area. My plan is to move that subwoofer over to the battery locker on the port side which has just enough room to still access the batter switch.

I'm looking for help re-connecting the heater hosing from the engine to the heater. The previous owner left some of the hose in place but it looks in pretty rough condition so I plan to replace it. See here and here for images of the detached hoses I found that was left inside the engine compartment.

Can anyone please help me confirm where the intake and return hoses should be connect? I'm assuming it the two places that are capped off as shown here?

Also, are there any minimum spec requirements for the heater hose? It seems like silicone is more durable than rubber, so is something like this going to last the longest?

Any help is much appreciated as always.

Thanks,

Jordan

[justgary]

Your images inline (for imbb, use the HTML link and delete everything except the part in quotes for IMG SRC):

Yes, those are the two heater points on the engine.  Use 5/8" automotive heater hose from a big box store.

[Rednucleus]

I'm assuming the old heater core will be used. Before hooking the lines I would first make sure the core is not eaking - maybe put 5-10psi air in a closed loop and see if it holds before getting a leaky core surprise.

Edited March 29 by Rednucleus

[Jordan22]

1 hour ago, Rednucleus said:

I'm assuming the old heater core will be used. Before hooking the lines I would first make sure the core is not eaking - maybe put 5-10psi air in a closed loop and see if it holds before getting a leaky core surprise.

Yes, using the original heater core. I already hooked it up to the battery (without any water) and the fan is working at least.

I'm not quite sure I follow exactly how I would run your test. Would you mind elaborating a bit? Last thing I want is hot water spraying all over the boat.

[Jordan22]

2 hours ago, justgary said:

Your images inline (for imbb, use the HTML link and delete everything except the part in quotes for IMG SRC):

Yes, those are the two heater points on the engine.  Use 5/8" automotive heater hose from a big box store.

Cool thanks for the imbb trick.

So, when you say those are the two heater points is one of them sending out how water and then the other is returning the water back from the heater core? If so, which one is which? 

[Rednucleus]

@Jordan22 if there are already hoses on the heater core, just need to cap off one and put some air pressure on the other with a valve to close the system, ideally wih a guage to watch for pressure drop. Don't go crazy with the pressure so you don't damage the core. If air pressure doesn't drop you don't have a leak. 

[justgary]

3 hours ago, Jordan22 said:

Cool thanks for the imbb trick.

So, when you say those are the two heater points is one of them sending out how water and then the other is returning the water back from the heater core? If so, which one is which? 

Send out of the block is the lower one in your photo.  Return is the upper one, just above the J-jose.  Note that it is possibly more common to see the send nipple on the intake manifold, just behind the thermostat cover.

On the heater end, it doesn't matter which is which.  I agree that testing the core with maybe 8 PSI is a great idea.  If it is out of the boat, just block one port with your hand and lip lock the other port.  If it ruptured because of a freeze, you will know instantly.  The odds of some tiny little leak are pretty small; it will either hold pressure or have a big split somewhere.

[shawndoggy]

The heater could be relocated to the observers compartment and you could leave the sub. Sub is going to sound 100% better under the helm than isolated from the cabin in the observers compartment. You could get heat to the captain with a pull out hot tube. 

[justgary]

2 hours ago, shawndoggy said:

You could get heat to the captain with a pull out hot tube.

Heh heh heh.  I have no need for a sub, so I put my heater under the dash.  I rarely tell anyone that I have heat on my feet and legs.  It is rare that we even really need a heater, so my wife always forgets that she could use one of the tubes for herself.  If it is particularly chilly and I'm wet, I put a towel over my legs and hog all the hot tubes.