heater matrix cleaning

Jimbo

1978 260z in yellow
Club Member
hi everyone.
i thought i would share a tip on cleaning out your heater matrix if its a bit blocked.
i took mine out as it was pretty much doing nothing and after flushing it through back and forth i managed to get flow through it but only a quarter of it heated up when flushed with hot water.
so i left mine filled with coca cola for 3 days just sat outside (on the advice of my dear mother of all people).
i flushed it out today and the **** that came out you just wouldn't believe!!:eek:
must have been about a cups worth of dirt and grime and rust came out of it.
i kept flushing it backwards and forward until it ran clear and now three quarters of the matrix gets hot.
im going to try the coke again for a few more days to see if any more comes out but its definitely worth a try before buying a new one.
 

Farmer42

Club Member
If you still have heating problems after flushing through, check that your inlet and outlet hoses under the dashboard are in good condition especially the right angled outlet one.

I had a similar problem earlier on in the year and went through all the same pullava as you with removing & flushing only to find that the right angle outlet hose had collapsed thus restricting the flow and stopping the matrix getting the hot water through it. It doesn't need to be kinked much to do this.

You can get a replacement hose from this lot:
http://www.carbuildersolutions.com/uk/CatalogueRequest

A lot cheaper and easier than ordering from the US.
 

Jimbo

1978 260z in yellow
Club Member
thanks for the info and link farmer42
funnily enough i ordered a 90 degree hose off ebay to replace mine as it had collapsed and it came from carbuilder solutions.
they sell quite a lot of interesting stuff dont they as i had their catologue through the post this morning and have been thumbing through it most of today.:thumbs:
 

Fairlineguy

Club Member
I have all ways used brick cleaner from the local diy store .its a mild acid so care has to be take to flush well .
You will find if you take it in to be done professionally they also use an acid to clean and flush them out.
Mind you I had my Z heater matrix re cored locally for £90
 

Jimbo

1978 260z in yellow
Club Member
thats good to know.
does the cleaner not react with the copper/brass the matrix is made from if its acid?

i actually use wickes own brand patio cleaner as a derusting solution as its really good at dissolving rust.
however im not sure i would trust it in the heater matrix
 

Fairlineguy

Club Member
I don't leave the brick cleaner in it for hours .it works fast
Started using it years ago when I had a boat and the water cooled intercoolers would
Block up with calcium deposits.
Never effected the copper solder but brought them up like new.
Mined you my best use for it is in my rental property for getting rid of the calcium
Deposit that builds up in the toilet pan.Lol
 

Russell

Club Member
what is the best way to get the heater matrix out?

Mine is completely bypassed from the engine bay and have been thinking about getting it going again. Not just going to plumb it back in though as it was probably bypassed for a good reason!
 

Farmer42

Club Member
It must be a common thing on 260Z 2+2's cos mine was also bypassed.

Normally the matrix is ok, it's the water valve that leaks. If you can avoid taking the matrix out I would cos it's a pig of a job and you need to be a contortionist to do it. I would connect it up first and put a bowl or a blanket on the floor to catch any water leakage and then look where the water (if any) leaks from. It will save you a lot of time and expense (speaking from bitter experience). You should also check the right angle hose to the outlet under the dash cos if it's kinked, the heater wont work.

If you do need to remove it, the driver's seat and the steering wheel need to be removed first to give you room underneath. You then need to disconnect all the rubber hoses, the heater control cable and remove the water valve. You will also need to remove the metal pipe & bracket that goes through the firewall. This should then expose the plastic cover to the matrix.

There are a few screws to undo to remove this cover and the heater matrix should slide out with a plate on the front. It's really fiddly to get out past the clutch pedal.

Getting it out is the easy part, putting it back in is a real challenge.

Good luck with that one!!
 

Jimbo

1978 260z in yellow
Club Member
In my 260 I managed to get it it by removing the panel in the drivers side footwell which is held in with screws and a flappy bit that you will need to detach from the control box (simply unhooks)
Then I removed the heater pipe work the.valve assembly and the piece that goes through the bulkhead
With all that removed the heater matrix slid right out no issues.
I didn't remove the steering wheel or the centre panel.
It is an awkward job as I'm fat and struggle in the footwell.
 
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