Series 3 Cooling System - a couple of questions.......

Hello all,
Having worked through many items trying to tidy things up, its time to turn my attention to the cooling system.
Its a 1973 88inch but with a later 2.3 petrol engine (code 11H), the cooling system needs an overhaul with hoses that have been bodged with joiners and some are now starting to crack, hose clips close to rusting through and theres a grumble that seems to be coming from the water pump.

A couple of Q's if I may:

1. The parts book lists two thermostats available, one 74 degrees and the other 82 degrees - which would be classed as standard fitment?

2. I've no radiator cowl or shroud fitted, so pretty sure the 4 blade fan isn't doing a great deal other than moving air around the engine bay - I can get hold of a second hand one, but would appreciate opinions on whether to take the opportunity, whilst I've got a few bob available and sorting everything else, to go for a Revotec electric fan conversion.

Temp gauge sits towards the upper half of the gauge, and rises when ticking over but never gets into the red - although quite close. Rad doesn't seem that old and looks in good order .

Thanks in advance.

Even if you do away with the 4 blade fan if water pump bearings are going you need to change it.82 degree stat is a good choice if you have a working heater and use it in the winter. Some folk fit 74 in summer and 82 in winter personally if your not towing 82 should be ok all the year round in the uk.

Many thanks for your reply Blackburn, I've already ordered new pipes, clips and water pump - so it's getting changed whatever. Have ordered both thermostats too, but wasn't too sure which to fit.
Also I neglected to mention that the heater is not working. No blower fan fitted and the heater matrix has been bypassed by the PO. Would the better option be the 74° thermostat then, as mainly summer use?
Thanks.

I'd stick to the standard 82 'stat personally. There's either a coolant problem or there isn't, a lower stat will just help mask any issue until it gets worse.
Give the radiator a good reverse flush and make sure you can see through it front to back with no blocked areas

Plus one with kermti's post. No problem running with out a cowl in the UK. Most of the cooling air going through a rad is mostly from the forward motion of the vehicle.[ unless it's a tractor or other slow mover ] Which is why things warm up more if just running at a stand still.

tottot said:

Plus one with kermti's post. No problem running with out a cowl in the UK. Most of the cooling air going through a rad is mostly from the forward motion of the vehicle.[ unless it's a tractor or other slow mover ] Which is why things warm up more if just running at a stand still.

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I'd feel better with a cowling on it though.......those metal fins are like blender blades.

Many thanks all for your input, rad will get a good flush whilst everything's apart.

Rodeo Joe said:

I'd feel better with a cowling on it though.......those metal fins are like blender blades.

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Dont I know it.......lost a set of meter leads to the fan not too long ago!

Causing me a bit of grief this one..........wonder if i can pick some brains please?

I've done the following:

1. New water pump, new gaskets, all new hoses, new thermostat (82°) and new radiator.

2. Fan controller fitted to top hose for electric fan.

3. Previous owner had bypassed the leaking heater matrix, by running a short hose from the 2 outlets on the thermostat housing (this looks like a 90/110 bottom housing with a series top housing, according to the parts manual) - see pics attached. This has been renewed.

4.Coolant added very slowly (took just short of 7 litres) and some added to expansion tank/bottle.

5. No leaks!

Now the problem!

1. I'm unable to get the drain plug from the block, dispite spending ages today trying to shift it, its all rounded off.

2. There appears to be no flow through the radiator - thermostat must be opening as the top hose gets hot and the fan controller brings the fan in, but only top inch of rad is hot the rest stone cold as well as bottom hose (obviously),

Assume there is an airlock somewhere, coolant at the PO bypass fix and at the temp sender in the head. Given hoses a good squeeze.

Temp gauge gets into red, even with fan running.

Any suggestions regarding bleeding, without using the block drain plug.
Thanks in advance.

the heater take of link pipe cut it in 2 and bung both ends,if you remove top hos and fill till it over flows youll know its full you could also look at the bypass thats the hose that goes from thermostat housing to water pump,if you remove the cast elbow you can see if its a large hole or a smaller one ,the smaler one sends more through the thermostat, whack the drain plug till it mushrooms a little then hammer a socket on to it,the shock will help loosen it

jamesmartin said:

the heater take of link pipe cut it in 2 and bung both ends,if you remove top hos and fill till it over flows youll know its full you could also look at the bypass thats the hose that goes from thermostat housing to water pump,if you remove the cast elbow you can see if its a large hole or a smaller one ,the smaler one sends more through the thermostat, whack the drain plug till it mushrooms a little then hammer a socket on to it,the shock will help loosen it

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Old skool! Love it!
(Those two hoses might chafe unless OP does summat about em!)

jamesmartin said:

the heater take of link pipe cut it in 2 and bung both ends,if you remove top hos and fill till it over flows youll know its full you could also look at the bypass thats the hose that goes from thermostat housing to water pump,if you remove the cast elbow you can see if its a large hole or a smaller one ,the smaler one sends more through the thermostat, whack the drain plug till it mushrooms a little then hammer a socket on to it,the shock will help loosen it

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Lovely, many thanks for pointing me in the right direction, that's done the trick - airlock gone and all good now.