Cooling circuit plumbing after PRT installation

I know the PRT is not a new topic but it seems there are still some doubts on the right plumbing, specially concerning the ehating matrix connections.
Some people complain for poor heating after PRT installation.
I did this dwg and I've already posted it in another forum, I've already exchanged with david, who agrees with this plan.
So I'd like to share it with you. I can share the dwg by mail if someone is intrested, just PM to me your email adress.
The heating matrix connection is quite strange, both inlet and outlet hoses are branched to the 2 main pipes going to the pump !

Yes, this is the correct flow diagram.:yesnod:

If you look at the diagram the heater flow comes from the 4 way connection that is fed from the pumped (hot) engine outlet. This also feeds the original (steel pipe) thermostat bypass circuit.

The heater return joins the other steel pipe, which is the original radiator(cool) return to (and controlled by) the original thermostat.

The other thing to note is that the inlet flow to the heater matrix is connected to theoffside of the two heater pipes on the bulkhead.

Note also that the flow through the radiator is reversed by fitting the PRT. This doesn't cause any problems.

david aiketgate wrote: Yes, this is the correct flow diagram.:yesnod:

If you look at the diagram the heater flow comes from the 4 way connection that is fed from the pumped (hot) engine outlet. This also feeds the original (steel pipe) thermostat bypass circuit.

The heater return joins the other steel pipe, which is the original radiator(cool) return to (and controlled by) the original thermostat.

The other thing to note is that the inlet flow to the heater matrix is connected to theoffside of the two heater pipes on the bulkhead.

Note also that the flow through the radiator is reversed by fitting the PRT. This doesn't cause any problems.

Please excuse my ignorance, but what is PRT??? :huh:

Start Google or Yahoo or wichever engine you use and tape " MG Rover PRT"

Note also that the flow through the radiator is reversed by fitting the PRT. This doesn't cause any problems.

David: this is another topic I'd like to exchange.
I see some discrepancies depending on the source. of infos
Usually the hot water enters from the TOP of a radiator and left cooled from the BOTTOM in the opposite side, this also is the natural cross flow of cold water.
The purge has also to be in a calm zone to favourite air separation.

The dwg from the Serv Manual

The hot water hose (#4) is connected on the left side where is the purge tap (# 9)

This is another well known diagram that I coloured IT'S DIFFERENT FROM THE SERV MANUAL

the radiator water inlet is in the TOP BUT on the right side

this meets this picture

and this radiator drawing, with the inlet on the top left and purge on the top right

I've not changed the hoses connections when I fitted the PRT, I did one hose at a time

bryan young wrote: Please excuse my ignorance, but what is PRT??? :huh:

i found this explaned it for me :blush:
http://www.mgf.ultimatemg.com/group2/common_problems/hgf_pages/cooling_system_modifications.htm

Titanium wrote:

Note also that the flow through the radiator is reversed by fitting the PRT. This doesn't cause any problems.

David: this is another topic I'd like to exchange.
I see some discrepancies depending on the source. of infos
Usually the hot water enters from the TOP of a radiator and left cooled from the BOTTOM in the opposite side, this also is the natural cross flow of cold water.
The purge has also to be in a calm zone to favourite air separation.

The dwg from the Serv Manual

The hot water hose (#4) is connected on the left side where is the purge tap (# 9)

This is another well known diagram that I coloured IT'S DIFFERENT FROM THE SERV MANUAL

the radiator water inlet is in the TOP BUT on the right side

this meets this picture

and this radiator drawing, with the inlet on the top left and purge on the top right

I've not changed the hoses connections when I fitted the PRT, I did one hose at a time

Yes, it seems that the original radiator layout is not normal. With the hot coolant entering at the bottom nearside.



Most radiators have the hot coolant enter from the top and return cool from the bottom.

The PRT (pressure relief thermostat) installation swaps the oem setup to top entry/ bottom exit. This setup works without problem. I have had this radiator setup for two years without any effects.