Replacing cooling hose BHH1083
Victor Smith (Harvest Gold 1089) had the "S" shaped hose behind and under the carburettors fail and relates how to replace this difficult item. (Sep 08)

he heater to outlet pipe hose BHH1083 is located between the carburettors and the heater where it connects with the heater and it extends down below the carburettors to connect to the metal by-pass pipe 90611532 which runs forwards over the top of the engine. In this case the hose had failed at the bottom connection with by-pass pipe, just before the clamping point with the jubilee clip. You can see the compressed band from the clip on the pipe above and a close up of the failure is shown alongside.

Close up of the failure of BHH1083 heater to outlet pipe hose from which a jet of hot coolant was escaping as liquid and steam. You can see the hose has split at a point which is just behind the engine so conditions can get very hot in that area - conditions which give a rubber hose a very hard service life.

The routine for changing this pipe follows most of the operations set out on Sheets 2 and 3 of page 12.37.01 of the MGBGTV8 Supplement AKD8468. In summary they are:

Remove the remove the air cleaners, then remove the two screws between the carburettors securing the choke cable clamp to the front of the air box, detach the choke cable clip at the back of the offside end of the air box, disconnect the hose from the underside of the breather filter, remove the fuel feed next to the inline filter, disconnect the two breather hoses alongside the rocker covers, disconnect the vacuum advance pipe, remove the air box, remove the six nuts securing the

carburettor adaptor and gently break the seal and lift the adaptor off with a slight rocking action so you have the carburettors attached. You will then have access to BHH1083, the heater to outlet pipe, for removal and replacement. Reassemble.

It is a good idea to replace the whole set of hoses at the same time. Complete sets of either the string reinforced rubber or the new silicone hoses are available from Clive Wheatley. You will need to replace the coolant with anti-freeze - so for reference the capacity of the MGBGTV8 cooling system with a heater is 16 pints (9.08 litres). You will need up to 3 litres of anti-freeze.

Useful references

See a PDF version of this V8NOTE386, More

Summary of the manuals for the MGBGTV8, More

New cooling hose sets for the MGBGTV8 in reinforced rubber or silicone from Clive Wheatley. More
Copyright reserved by the V8 Register