View Full Version : Heater Core Replacement DIY w/ Pictures

07-11-2013, 09:07 PM
So, I thought my heater was bypassed because the PO winterized it. Hooked it up and went skiing. Heater core leaked and boat filled with hot water VERY quickly. So I decided to replace the core. Boat is a 2002 X-Star w/ HeaterCraft 200H heater.

Phillips screw driver
Wire cutters (for zip ties)
Electric screwdriver (makes life much easier)

Heater core- $100 from Heatercraft, $34 from NAPA Auto Parts. Part number is 660-3100
Some 1/4" or 1/8" adhesive backed foam. Around 2" wide, you need about 2 feet of it
OPTIONAL: 5/8" hose or clamps if yours are broken.

Note- I took the kick panel off, this could probably be done through the sub hole if you have it.

1) If you have it, remove the sub-woofer under the dash.

2) Disconnect the wires for the engine control module and the perfect pass. The connectors for the ECM are shown below. (I took the actual units off the kick panel, this was not necessary.) You push down on the piece near my thumb in the picture. On the other connector, lift up on the plastic loop to remove the connector.

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0017.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0017.jpg.html)
http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0016.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0016.jpg.html)
Sorry for the lousy pics

3) Remove the two phillips screws on the lower left of the kick panel.

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0020.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0020.jpg.html)

4) Cut the two zip ties securing PP wires at the top left of the kick panel

5) Remove the panel. To get it out, you have to lift it up and then slide the bottom out. Make sure the wires that come over the top left do not get caught. Cut the zip tie holding the heater hose onto the back of the vent, and slide the hose off.

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0021.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0021.jpg.html)

6) Look up at the heater. On the right side, you will see two phillips mounting screws into the fiberglass. Remove these. It is not necessary to remove the left side mount

7) Remove the (4) screws holding the mount for the heater.

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0024.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0024.jpg.html)

8) Remove the (4) screws holding the black left cover onto the heater

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0023.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0023.jpg.html)

9) You can now see the core. Loosen the hose clamps on the water lines and pull the hoses off (I had to cut mine)

10) On the bottom of the heater, between the two hose connections, there are (2) more screws. Remove these.

11) Remove the metal plate that slides in over the hose connections (you have to lift it up and out). Its the tan/brown piece in this pic

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0026.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0026.jpg.html)

12) Slide the heater core to the right, keeping it level

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0028.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0028.jpg.html)

13) Prep your new core. I happened to have some of the exact foam that the old core had, but I’m sure it could be found at the auto parts place or home depot. Stick the foam around the edge of the core. I also put some little strips around the hose connections.

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0029.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0029.jpg.html)

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0032.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0032.jpg.html)

14) Slide the new core into the hole. It is important to keep the core level when you slide it in, otherwise it will not insert all the way.

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0034.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0034.jpg.html)

15) The cut outs on my metal plate were a little too narrow for the new core, so I hit it with a grinder to open it up. this is the piece

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0033.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0033.jpg.html)

16) Slide the metal bracket into the core. It fits with the two screw holes down, and the vertical wall to the right.

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0036.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0036.jpg.html)

17) Screw the metal bracket in from below

18) Use the (4) screws to install the black cover onto the side of the core

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0041.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0041.jpg.html)

19) Use the (4) screws to install the bracket to the core. Don’t tighten the screws all the
way, leave some play in the bracket.

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0042.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0042.jpg.html)

20) Use the (2) screws to install the bracket to the fiberglass, then tighten the ones that attach it to the heater.

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0043.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0043.jpg.html)

21) Attach the heater water lines

22) Reinstall the drivers kick panel. Before doing this, I stuffed the wires that go over the left side up against the heater. This kept them out of the way. Make sure you rout all your PP wires over the top of the panel. Again, the panel top needs to go in first then slide the bottom in. I had to wack it with my hand to get it to go all the way in. Push the panel down to seat it. It will need to go down further than you think.

http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0044.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0044.jpg.html)
http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0045.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0045.jpg.html)
http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0046.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0046.jpg.html)
http://i1090.photobucket.com/albums/i367/will199207/Boat/DSC_0048.jpg (http://s1090.photobucket.com/user/will199207/media/Boat/DSC_0048.jpg.html)

23) Reinstall the two screws at the bottom left of the kick panel. If its all the way seated, they should go in easily to their old holes.

24) Reinstall your sub woofer (don’t forget to connect the wires). It helps to have an extra set of hands hold it from behind.

25) Connect the ECM and perfect pass.

26) Zip tie the PP wires to the two plastic loops at the top left of the panel.

07-11-2013, 11:24 PM
does the heat only come out of the one vent, thanks for post with pictures. looking to install one but not sure where to put the unit

07-12-2013, 01:36 AM
The heat comes out of there and a vent on the passenger side. The tube runs around the bow

07-12-2013, 08:22 AM
Nice work and thanks for the NAPA tip.

07-12-2013, 08:41 AM
Nice thread. I replaced the heater core on my 1996 205 last fall. The steps were the same, except I had the 100 series heater. The only difference is the 100 series has the 12v blower (looks like a bilge blower) in the box with the core. I had to remove the entire 100 series box which was only 4 screws. Then I had to drill some rivets and replace the core. I could not find the 100 series core replacement anywhere so I had a local radiator shop repair it. Made me feel good to support the shop, he is truly the "little man".

05-18-2016, 12:30 PM
@willg, Any chance you still have these pictures and can make them available again? I think this thread is exactly what I need to guide me through a heater core replacement on my boat. Thanks!

05-20-2016, 03:40 PM
@willg, Any chance you still have these pictures and can make them available again? I think this thread is exactly what I need to guide me through a heater core replacement on my boat. Thanks!


05-24-2016, 02:03 PM
Thanks willg!!! I will be working on this project this weekend.

05-24-2016, 09:50 PM
Had the same thing happen this weekend....boat filled with hot water. I'm going to go cheap and bypass for now, but will probably replace the heater in the off season.