Leaking heater matrix

[MCBladeRun]

Hi guys

Had a lot of good stuff put on the car and I guess I was due a problem. I was doing the gearshift lever bushings and one of the screws that held down the gaitor plate fell into the passenger footwell and that's when I noticed the damp in the carpet.

So I removed the carpet and there was a bit of a damp patch? Turns out there's a coolant leak from either the matrix or the pipe connections - I can't tell at this time.

Would it be the case that I could connect the in/out coolant pipes together temporary while I remove the matrix for a service?

Has anyone done this without removing the dash? This seems like a winter job to me

 

[jonbills]

You can connect the pipes in the engine bay.
Mine leaks like that, always has done but only happens when the heater controls are set fully cold (so I leave it on half hot).
I think it is the valve.

 

[Geoff-R]

I was going to say the valve looks like it could well be past it and could be the reason for your leak rather than the heater core. I would bypass it for the time being then remove the valve and inspect before going down the route of removing the dash to get the matrix out.

 

[Rob Gaskin]

Usually the valve. The matrix will come out of the box when you have removed one side.

 

[MCBladeRun]

Cheers guys, I'll connect the pipes in the engine bay as jonbills suggests - I do have it set to cold only.

The valve you say, is that it in the picture with the wire going to it from the controls?

I saw on the fsm that the matrix does pull out once you remove the side panel. But if it's that valve I guess that is a dash removal?

Are these pipe valve and other components available or are they a universal part? I am also thinking about doing an Aircon mod to the car so, don't know if these old matrix and fan box are worth keeping / restoring?

 

[Paul_S]

I bought my replacement valve from here https://www.amayama.com/en/part/nissan/27116e4400 if that helps.

 

[Rob Gaskin]

Yes that's the valve, but you don't need to take the dash out. I've removed two heater boxes with dash in situ.

Lots of cars run with the pipes connected and heater bypassed. I've done it and some race cars do too (remove heater to reduce weight).

 

[IbanezDan51]

Its very rare that those valves don't leak... Every 240Z ive had ive replaced them.

 

[MCBladeRun]

Thanks for the replies gents.

Would I need some form of cap to go on each pipe in the engine bay area? Or do I take it back to the pipework I think is mounted onto the engine IIRC?

Thanks for the link Paul_S

 

[Rob Gaskin]

Just get a piece of new supple pipe and bend it into a 'u' shape and connect it to the pipes that were connected to the heater. Or have I misunderstood you?

 

[MCBladeRun]

Hi Rob, that's what I needed. Just didn't know if it was a bad idea to connect the 2 pipes together. Some flow and return systems don't like that sort of thing - but I am more used to central heating circuits in houses than I am of vehicles

 

[Alphabettispaghetti]

Would it not be easier/make more sense just to change the valve?

 

[Rob Gaskin]

Hi Rob, that's what I needed. Just didn't know if it was a bad idea to connect the 2 pipes together. Some flow and return systems don't like that sort of thing - but I am more used to central heating circuits in houses than I am of vehicles

In a house you need a least one rad in the circuit I'm told. On a car you have that anyway. I've done it on two cars and it was fine.

 

[MCBladeRun]

Would it not be easier/make more sense just to change the valve?

Could do, but I want to stop the leak for now - so car can still be usable. And when valve part arrives I can put it back together and see if I've cured the problem. I wouldn't want to remove the dash at present. Hence, winter job

 

[Rob Gaskin]

Could do, but I want to stop the leak for now - so car can still be usable. And when valve part arrives I can put it back together and see if I've cured the problem. I wouldn't want to remove the dash at present. Hence, winter job

You don't need to take the dash out just the centre console area with the controls levers and vent.

 

[MCBladeRun]

You don't need to take the dash out just the centre console area with the controls levers and vent.

Ah, I see. Thanks Rob, thought it was a bigger job. I've ordered that valve part - gosh they're expensive elsewhere! Over £100 in some places. Going to get some 3/8" pipe tomorrow and try to isolate the problem.

 

[Rob Gaskin]

It's a PITA but definitely doable without removing the dash. If you are just doing the valve no need to take anything out but the valve.

 

[AliK]

There's a GREAT alternative matrix and write up below if of interest ...

https://www.classiczcars.com/forums...ive-escort-core-into-260280/?&page=3#comments

 

[Farmer42]

If you want to stop the water leak in the meantime, you need to join the 2 pipes that come out of the block in the engine bay together. One is Y shaped and bolts to the side and the other is a stub that comes out the rear. Both should have pipes going through the bulkhead to the heater and these need to be disconnected.

When you try to replace the valve, I would recommend removing the seat and steering wheel as this will give you better access.

 

[MCBladeRun]

If you want to stop the water leak in the meantime, you need to join the 2 pipes that come out of the block in the engine bay together. One is Y shaped and bolts to the side and the other is a stub that comes out the rear. Both should have pipes going through the bulkhead to the heater and these need to be disconnected.

When you try to replace the valve, I would recommend removing the seat and steering wheel as this will give you better access.

I've a left hand drive, so just the passenger seat I take it?

Cool, I thought there was something that came off the engine block. 3/8" pipe is right?