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BaBaLoO

DIY heater core

Does anyone have any tips or notes on how to replace the heater core for a 3 outlet heater? looking to replace it in the next couple days. thanks

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Try to set up a video before you start so we can all get a good laugh and hear some @#$% words. You will know what a sardine feels like. :yahoo:

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Try to set up a video before you start so we can all get a good laugh and hear some @#$% words. You will know what a sardine feels like. :yahoo:

hahaha ya I bet. my main concern is if I have to take the sub panel off?

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The problem with a how-to of this nature is that everyone's boat is different. My sub is a PITA to find all the screws buried in the carpet. Then the whole box pulls out in one piece. Once I get that far, the core is right there.

The case itself has 2 screws on the end to remove the core. But you will most likely need to remove the whole case from under the dash to have enough room to do that. As I recall there are like 4 bolts holding the case to the dash wall. Pull the hoses, unhook the wires & pull it all out. Your wires may need to be cut, in which case you might chose to install some plugs to make them easily removable. If the hoses are too tough to remove, then cut them close to the core. Then you can work on it out from under the dash.

Be sure that your core is mounted so that the inlet/outlet hoses are on the bottom side. Then you can install some radiator flush Ts or quick release fittings in the lines in the bilge to make it easy to drain in the future.

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The problem with a how-to of this nature is that everyone's boat is different. My sub is a PITA to find all the screws buried in the carpet. Then the whole box pulls out in one piece. Once I get that far, the core is right there.

The case itself has 2 screws on the end to remove the core. But you will most likely need to remove the whole case from under the dash to have enough room to do that. As I recall there are like 4 bolts holding the case to the dash wall. Pull the hoses, unhook the wires & pull it all out. Your wires may need to be cut, in which case you might chose to install some plugs to make them easily removable. If the hoses are too tough to remove, then cut them close to the core. Then you can work on it out from under the dash.

Be sure that your core is mounted so that the inlet/outlet hoses are on the bottom side. Then you can install some radiator flush Ts or quick release fittings in the lines in the bilge to make it easy to drain in the future.

Cheers thanks Bill, ill give it a shot this week.

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yup 2 hours in and I already want to burn the thing down. I cant even get the sub box off! the screws are behind the box and there is no way I can get to them. I wanted to just the box in to free it up from the screws!!! I cant barely get to the 4 bolts you were talking about to remove the whole case. Before I try to attempt again is there anyway to get case out, and disconnect everything without removing the sub box( stock sub box from malibu) or should I just take it in to bu and get them to do it. what am I looking at to get it done by a pro if I supply the core??

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one more thing

:blowup::mad: :mad: :rant: :rant: :Frustrated: :frustrated: :Frustrated:

anyone in the vancouver bc area have any experience changing one out?

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one more thing

:blowup::mad: :mad: :rant: :rant: :Frustrated: :frustrated: :Frustrated:

anyone in the vancouver bc area have any experience changing one out?

Hey, You are supposed to be making us a movie!

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HEhe, ouch. Sounds like knuckles are gettin bloody over there.

Wish I could help you. Like I said, every boat is a bit different. My sub box is not stock, but the screws are embedded in the box carpet going in at an angle to the floor. Then there is a trim piece on the left side wall that has to be removed (on my 05), that has like 2 easily spotted screws with washers.

No way I could get behind my sub box without removing it. First time took me a couple hours. Second time took like 3 minutes. I really had to hunt for those screws in the carpet. Since then I've done it on an 08 Vride too, and went thru the same issues finding all the screws.

Good luck getting yours out.

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If I decide to just put in a t valve to close it off and replace later would the fitting be 5/8? and would I just have to cap off the hose thats bringing water to the core or both hoses?

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Not sure of the diameter. But 5/8" is close. You will need to join the two hoses together. I've done that just using a small piece of PVC or copper tubing.

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Yes, it's 5/8"

You can do it with home depot parts... (they are flush with these right now for spring)

one of these

9e770d23-e499-414e-ac47-29c58326319d_300.jpg

with one of these in the middle

925030_1486055_290.jpg

and one of these on the other side:

2979013_3635084_290.jpg

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Yes, it's 5/8"

You can do it with home depot parts... (they are flush with these right now for spring)

one of these

9e770d23-e499-414e-ac47-29c58326319d_300.jpg

with one of these in the middle

925030_1486055_290.jpg

and one of these on the other side:

2979013_3635084_290.jpg

awesome thanks for the pics.

Bill, do you mean both in and out hoses?

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awesome thanks for the pics.

Bill, do you mean both in and out hoses?

You should have 2 hoses on the core.... pull them & use the fitting like Shawn described to join the 2 together. Actually I'd forget about the valve & just join the two. You want the water to flow (like it does with the core in place) so I don't see any point in putting a valve on it.

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You should have 2 hoses on the core.... pull them & use the fitting like Shawn described to join the 2 together. Actually I'd forget about the valve & just join the two. You want the water to flow (like it does with the core in place) so I don't see any point in putting a valve on it.

yeah, what he said. forget that middle pieces. female on one hose, male on the other, screw together.

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I'm having my local dealer replace the 3 outlet heater core in my 08 23. They said it's a $160 part... Is this true? seems kind of steep to me.

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Yea, it's true. They get a lot when you call it a "marine" part. I've replaced them with car heater cores for like $25 & never had another problem with it. You'll have to bring your core into a local auto parts store to get them to cross reference it.

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These cores tend to be similar to an older Ford core, specifically the 5/8" short straight hose attachment lines. On the larger heaters the cores are longer than many auto parts stores will carry, so you might end up deciding to make a spacer rather than keep looking for the exact core. A simple plastic 5/8" heater hose splicer also works well as a bypass device. The typical automotive core is not made to handle hard corrosive lake/river water for very long, thus the life expecancy is pretty short. They really hate frozen water and many fail due to that as the solder is pretty weak. Over winter, they need to be filled with antifreeze or dry. I have a shut off valve to stop the water going through the core when not needed, so that is only open in spring / fall, or when the CFO requests heat.

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