Strange interior heating problem SORTED

[BigDaddy]

Did you try a hose directly into the matrix?

[Joez4]

Did you try a hose directly into the matrix?

I couldn't get the hoses off they were really stuck on and I couldn't reach very well, I did contemplate cutting them off and replacing them but couldn't find them anywhere, anyway from what I've read regarding the design of the matrix directly flushing it has little effect but is worth a try I guess

[BigDaddy]

Well I back flushed the matrix today. Took a bit of fiddling to get the hoses off but a hose pick set from euro car parts (£2.40) sorted it pretty quickly.

I bought a clear hose so I could see what came out and man the amount of dirty crud was unbelievable. In fact some of it looked like stones from the garden which I don’t really understand. Either way after I’d ran the hose for a while and turned it on and off a few times with my inline hose valve (very useful), the water finally ran clear after 3 buckets worth. I refilled the matrix with coolant, hooked it all back up and bled the cooling system the best I could. I’m never sure if I’ve bled it properly but I tried my best.

Not been for a long run in it yet but even just going round the block I can feel there’s a big improvement. Hot air out of the middle vent is now actually hot so hopefully there’ll be no more complaints from passengers.

Definitely worth back flushing the matrix though if anyone is considering it, it’s easy enough to do.

[enuff_zed]

some of it looked like stones from the garden which I don’t really understand.

That's what radweld looks like when it is put in a cooling system.
Well done for shifting that!

[BigDaddy]

Yeah I think the previous owner had put either rad weld or k seal in there to try to solve the radiator hose leak. I just replaced the hose instead as the radweld hadn’t sorted the leak, it just clogged up the matrix etc with crap. A new hose is only £30 and takes 5 minutes to fit so he should’ve just done that.

Anyway after a bit more of a test run the passenger side is still not blowing hot. A lot of rubbish came out of the matrix but maybe there’s just more in the system, or it’s a pesky air lock that I couldn’t remove. In fact once I started pumping the water through the matrix there was a massive bubble into the bucket. which presumably was the old airlock that was causing me issues before. I guess it’s back. Damned difficult to eradicate.

Either way I know the matrix is a million times cleaner that it was now so that’s something at least.

[enuff_zed]

Yeah I think the previous owner had put either rad weld or k seal in there to try to solve the radiator hose leak. I just replaced the hose instead as the radweld hadn’t sorted the leak, it just clogged up the matrix etc with crap. A new hose is only £30 and takes 5 minutes to fit so he should’ve just done that.

Anyway after a bit more of a test run the passenger side is still not blowing hot. A lot of rubbish came out of the matrix but maybe there’s just more in the system, or it’s a pesky air lock that I couldn’t remove. In fact once I started pumping the water through the matrix there was a massive bubble into the bucket. which presumably was the old airlock that was causing me issues before. I guess it’s back. Damned difficult to eradicate.

Either way I know the matrix is a million times cleaner that it was now so that’s something at least.

As I said before, the inlet and outlet of the matrix are at the same end. So eventually the water will just give up trying to get to the far end and head off down the outlet pipe. To a small extent, forcing water in at a higher pressure than normal may even serve to compress the crud into the far end of the matrix.
Street had some success I believe by rigging up a pump and circulating some kind of heating system cleaner round the matrix. But even then I don't think it was a total cure.

[BigDaddy]

Well I did pump the water into the outlet to try and get it to flow against its usual path and it was at least a partial success as a lot came out. But there presumably is still more in there. I’ll probably run around in it for a bit then repeat the process. It wasn’t too tough and maybe it needs a few goes.

I don’t want to give up yet!

[enuff_zed]

Well I did pump the water into the outlet to try and get it to flow against its usual path and it was at least a partial success as a lot came out. But there presumably is still more in there. I’ll probably run around in it for a bit then repeat the process. It wasn’t too tough and maybe it needs a few goes.

I don’t want to give up yet!

Just a thought, and definitely not something you want in the whole system, but a friend managed to clear a similar blockage in an old Landrover by pumping a load of Viakal in there and leaving it overnight.

[BigDaddy]

Well it’s pretty easy to isolate the matrix and I could pretty easily do that so I’ll give that a go next time I think. Only £3 for 500 ml as well! Thanks for the tip.

[Street]

Not sure if this works but this was my setup. I got it back to about 70% on the passenger side. Jeff mentioned in the video enhanced it when he did it by introducing a heating element to the bucket to keep a constant warm cycle.

[BigDaddy]

That looks pretty decent idea and not difficult either, could I just ask what sort of pump you used? I think I’ll give it a try if that worked for you. 70% heat would be a lot better than nothing.

[Street]

That looks pretty decent idea and not difficult either, could I just ask what sort of pump you used? I think I’ll give it a try if that worked for you. 70% heat would be a lot better than nothing.

It was this one for £21. Discontinued but it was a few years ago and must have been superseded by something better by now.
https://amzn.eu/d/a8uiQvN

[BigDaddy]

Thanks! Yeah, looking on Amazon there are plenty of similar pumps. A 500 watt water heater isn’t much money either. Did you just leave it running for a few hours then? I could always set it up on a Sunday morn and leave it for the day.
Looks like a mad scientists experiment in a way, the kids will love it.

[Street]

Exactly! Get all scientific with a thermometer and keep measuring the output

I left it running overnight for a few consecutive days. Each morning back flushing with the hose to clear out anything that became dislodged.

[BigDaddy]

I just flushed the matrix again, swapped hoses a few times and did it both through the inlet and outlet. The inline hose valve I bought is quite good as it allows you to repeatedly turn it off and on which seems to dislodge more dirt. Anyway I got a load more crud out of there today. I will give it another flush in a few days time then do the pump thing I think. It is nuts just how much crap there is in there but then I guess a radweld bottle holds quite a lot of gunk, plus the car is 20 yrs old and I have no idea what the previous owners put into it.

I can’t help think the matrix is almost like a filter for any crap in the cooling system. I only drove it for 10-15 minutes after the last flush and it accumulated a load more stuff in there which must’ve swished round and then got trapped in the matrix. I hope that a couple more flushes will get most of the crud out of the system.

Passenger side is no longer blowing cold at least. It’s not hot but it’s not cold, so it has improved. I think anyway, the weather is a bit better so it’s hard to say really, but I think it’s improved. Drivers side was always pretty hot but now that as far as I can tell is a bit hotter as well so the flushing thing has been worth it so far I think, I just need to get more intensive.