1.8t into mk1 heater matric plumbing

Hello folks,

 I seem to recall from somewhere that when installing the coolant pipes from the 1.8t engine (BAM in my case) into the mk1 heater matrix, a bypass is required as to avoid blocking the flow when the mk1 heaters are turned off. I presume that the mk4 platform matrix had an internal bypass. Can anyone confirm ? If so, do I run a pipe between the heater inlet-outlet pipes so that the water can keep flowing if the mk1 heaters are switched off ?

cheers

phil

yeah what it is the mk2/3/4 matrix isn't closed off when the heaters are set to cold, instead theres a flap inside the airbox to divert the air flow round it.

so ideally you should put a T piece in just after the matrix feed so coolant can still flow when heaters are set to cold, I found the perfect thing on a MK3 automatic but have a mooch round you should find something

Hi guys,

Sorry to comment on an older post. but I was wondering if you could elaborate on the advice rubjonny gave? I am currently putting a BAM into a mk2 Scirocco and have the same issue with the heater matrix plumbing!

My question would be,  Do you need two T pieces between the feed and return to the heater matrix, positioned just before the heater cut off flap?

If I am thinking about this wrong would it be too cheeky to ask if you could draw the setup and post a pic :/

Cheers guys!

How.many T pieces you need depends on how you have the coolant system setup

Imagine the heater.matrix as a loop allowing coolant to flow, if you close the valve this stops the flow. You need to T in before the valve a pipe which can bypass the matrix and allow coolant to flow again. If there are no spare outlets you can out another T on the output pipe from matrix and link it back in there

Hi Gandalf,

As above really, with mine I ended up getting 2 tee pieces. This allowed me to have the feed to and from the matrix but the tees allowed a bypass pipe to be installed before they entered the matrix. That way if you close the heater it bypasses and maintains circulation. 

It's been a while but I seem to recall thinking it wasn't necessary after I did it as the bam coolant layout had a bypass in it somewhere anyway but it didn't do any harm

Hi Guys,

Thank you both very much for your very fast responses!
I will have a good look at the system and try to find the bypass already in there! But will also order a couple of t pieces just in case!

By the way how much of an animal was the BAM conversion in the end? Worth getting a LSD?

Again Thank you both!