Leaky heater matrix

Site Subscriber Joined: 23 Jan 2005 Posts: 502

Off on a trip in the car tomorrow. 400k mostly motoway. Want to use the 19 as I have family + luggage + golf clubs etc, which can go into the trailer. (Must fit a tow ball to the Pugeot).

Anyway I have been losing a small amount off coolant. And checking around the car, I noticed some white traces on the bottom of the heater matrix. But itâ€™s not wet so a small leak.

So on the way home I stop by Renault to ask the price of a new one and find they have one in stock for 100 â‚¬, which I took. Now reading around the forum A: itâ€™s not surprising that Renault had one for the 19 as it also fits Clioâ€™s ect. B: The things a total pain to fit. Shocked

No time to change it so Iâ€™ll put it in the trailer add some leak sealer to the coolant and hope for the best. Cool

Has anyone had one start to leak really badly e.g. Explode? Crying or Very sad

The thing has a copper pipe so with the cast iron block and alloy head its no wonder the coolant goes brown.

Forum Moderator Joined: 02 Mar 2004 Posts: 19978

I have yet to see one explode. The leak out, which can range from a light mist which you need to look colsely for to a small puddle on the floor mat in the morning. Never seen out pouring out.

In fact I have seen one go bang but the headgasket was away on that car and the pipes burst and the rad had swollen right out due to the pressure.

Site Subscriber Joined: 23 Jan 2005 Posts: 502

Well the old girl made it. 1000 km in all.

On the way back the trailer had a table lashed on the top and was well loaded down. Makes the rear feel a bit hoppy as the Koni`s are a bit stiff. Keep on good roads it`s OK.

The radiator sealer seems to have worked for the moment.
On starting in the mourning I could smell coolant as the heater warmed up but itâ€™s stopped.

Changing the matrix is a nightmare. Left hand drive so the pedals and steering column are in the way.
A.C. evaporator filling up the hole behind the engine with the fan.

Renault fun. Got the thing now so will give it a go.

Newbie Joined: 17 Nov 2004 Posts: 13

it's not that bad. if i could do it, so can you. the pedals are on the way, but, if you unscrew the dash bolts, just pull it inwards just enough the matrix to slide in front of the pedals, you'll be ok. you don't need to take the dash out.

also, use a latex glove for engine compartment hoses to stop the coolant spil. that 'll save you from flushing the coolant.

At least, that' for F3N

Site Subscriber Joined: 23 Jan 2005 Posts: 502

Got it changed after a lot of work. Smile

Pics.

The heater box inside the car is fixed with two bolts from the hole under the screen just like the non AC cars. The one on the left is holding down the end of the AC evaporator box, the one on the right is under it!
You can raise it up a little but not enough to get at the bolt. Confused

Now to remove the box you have to open the gas pipes, like get the AC repair van around or go to a garage the remove the gas, and then back after you have finished the recharge it. 100 quid for nothing. Mad

Managed to break the plastic around the bolt. Wink

By supporting the dash on straps through the doors and releasing the nuts under the steering column I managed to get the heater box back and around enough to slide the matrix out. Thanks for the advice from JohnelP.

Fixed the right side of the heater box back with a large self tapping screw from under. Wink

Water must sit under the Evaporator box causing the screen to mist after the cars been parked in the rain; have to run the AC on recycle to clear it. So I drilled a small drain hole.

Why was it leaking?

Coolant has been sitting in the bottom of the box causing the copper to go green.

But the real problem is the seal on the pipes as they pass through the cast plate on the inlet outlet end.

If your matrix is blocked up, these brass spring things that are inside for some reason must be hard to clear.

Web Page Name

Think I over did it with the pics. to big; last one as a link.

Forum Moderator Joined: 02 Mar 2004 Posts: 19978

good job. doesn't look to bad tbh, considering ac systems are normally a big pain!

Well done matey.