The Classic Machinery Network

I wonder if any Gardner expert out there can help me? The revs do not drop quickly enough when the the driver comes off the accelerator in our 5HLW-powered Bristol. This makes changing up a gear on hills problematic. An external examination shows that the governor advance lever is held tight against the accelerator linkage and there is no lost movement at any point - if you take your foot off the pedal it all snaps back quickly. Anyone any ideas why the revs don't drop immediately?

Many thanks!

Hi Nigel and welcome to CMN my initial guess here would be that the fuel rack could be sticking slightly, spray some freeing oil in it and see if that helps; the one company that I worked for had an 8LXB powered 400 series Sed/Atk that once broke down on one of the local services, a quick spray of freeing oil and movement of the rack and it was off again with no problems.

Jeremy

Hi Jeremy
Thanks for your input there. The rack is free, that was our first port of call and in fact all the linkages are free and well lubricated. I'm wondering if its an internal to the governor or fuel pump problem perhaps?

Nigel

If the revs pick up quick but dont drop quick and it holds revs with out hunting I would think the governor is working ok as it is govening and the problem is internal fuel pump problem
As far as I know the governors job is to tell the motor what speed to run, how quick the motor reacts to that speed is more the fuel side
But I really dont know anything about these


Paul

nigelrbfurness wrote:Hi Jeremy
Thanks for your input there. The rack is free, that was our first port of call and in fact all the linkages are free and well lubricated. I'm wondering if its an internal to the governor or fuel pump problem perhaps?

Nigel

Offhand I can't recall if its weights in the governor or not but I think that it is; I wonder if the springs that return the weights have gone weak over time?
What happens if you rev the engine and using your finger physically move the rack back to the tick-over position; does it die off quicker then?

Jeremy

Hi,
Long time since I worked on these but have you lubricated the injector pumps

Don't bother with freeing oil, you wont spray it in there anyway

On the side of both injector pumps you will find a small screw, (2 BA) , I think.

Inject about 30 cc. of engine oil into the three cylinder pump and 20 cc. into the 2 cyl. pump. (This should be done every major service).

This will lubricate the racks, or "sliders" as Gardner called them and also seep into the governor housing to oil the governor.
Fred

Thanks Fred never ever done this on a Gardner before perhaps this was not on the LX range on which I worked? The two aluminium covers were missing from the 8LXB pump that covered the rack where the two parts of the pump joined each other on which I had to free the sticking rack on.

Jeremy

Jeremy Rowland wrote:Thanks Fred never ever done this on a Gardner before perhaps this was not on the LX range on which I worked? The two aluminium covers were missing from the 8LXB pump that covered the rack where the two parts of the pump joined each other on which I had to free the sticking rack on.

Jeremy

Hi Jeremy,
The pump lubrication never changed from the 1940s 3 LWs and 6 LWs that I worked on in the Smith excavators, or the 8 cylinder marine units from that era which I looked after, right through to the 6 LX units we had in the Guy Big J tractor units from the late 1960s into the 70s.
I'll see if I can find my old 6LX manual. It should be in the garage somewhere
Fred

FOWLER MAN wrote:

Jeremy Rowland wrote:Thanks Fred never ever done this on a Gardner before perhaps this was not on the LX range on which I worked? The two aluminium covers were missing from the 8LXB pump that covered the rack where the two parts of the pump joined each other on which I had to free the sticking rack on.

Jeremy

Hi Jeremy,
The pump lubrication never changed from the 1940s 3 LWs and 6 LWs that I worked on in the Smith excavators, or the 8 cylinder marine units from that era which I looked after, right through to the 6 LX units we had in the Guy Big J tractor units from the late 1960s into the 70s.
I'll see if I can find my old 6LX manual. It should be in the garage somewhere
Fred

Did Gardner ever change anything Fred?

Hi Pete,
As you say, Gardner fiercely resisted change.
Below is the page from my 6HLX manual from the 1960s showing the oil filler plugs in the pump gallery covers, ( No.6 in the diagram).
The manual says check every 12,000 miles.