Fuel Pump Ticking

[Cutrog1]

When I switch on, without starting the engine, the pump naturally pumps rapidly, but slows to a slow tick once per second. Is this normal and I presume this is why there are drain holes at each end of inlet manifold?

 

[Bob_Spidell]

Normal (more-or-less). The pump will click rapidly to fill the carburettor float bowls, then slow to once-a-second or two (or three) when the floats close their valves and pressure builds up. The pressure drops slowly--I think due to some internal leakage in the pump--then the pump will fire again. If the pump continues to pump rapidly after 5-10 seconds it's usually caused by an air leak on the inlet side of the pump. The drains on the intake manifold are to drain leftover fuel from 'wall-wetting' on a cold start.

 

[Cutrog1]

Thank you so much..... I was of course getting the usual 18 mpg before covid lockdown anyway, but it's a long time since I have been able to go out for a long journeyand all I do is play in the garage. Mind you, she is looking better than ever.

 

[Healey Nut]

The drain holes in the manifold are there for if you flood the engine trying to start it , you wouldn’t want a whole load of fuel going bang at once should it decide to fire .

 

[Cutrog1]

Thanks fellers. So.......I have now spent some time with a friend yesterday tuning carbs with colourflow and suction gadgets. All set up perfectly on a warm engine and drove better than it has ever done....took out ALL spark plugs and colours were perfect on all......yesterday!
Today...started cold and felt like one or even two pots not firing!! Once warm...it felt better......but not sure...

This is where I was two weeks ago when I thought I had a problem with pots five and six. ie. When I removed sparkplug lead on 5 and 6 it made no difference.! I suspected head gasket (water between cylinders?). Removed head and took it to a trusted specialist who said there was a significant warp ......so he skimmed.

Now I have exactly the same problem. I WILL NOT ADJUST THE CARBS AGAIN! Any ideas?? Timing good.....about 3/4 inch before top dead centre. (10 degrees I presume)

By the way...removing 5 and 6 plug leads has no effect on tickover.

 

[Healey Nut]

Both my BJ8s ran rough for the first couple of minutes after starting until the engine temp started to build and fuel pressure became stable etc .
Healeys run best hot and should be set up to run at peak temp of around 180/190 degrees .
Did you check the valve clearances when hot after doing the head work ?

 

[Cutrog1]

Thanks...
No, haven't checked the rockers.....will do. 12thou cold is the measure. (?).However, having had the identical problem prior to their removal....I live in faint hope.
I wonder if to temporarily block off both the engine breather pipe on the rear filter and the servo pipe.

How about float levels?

 

[DerekJ]

As the saying goes, most carb problems are electrical. Check and or replace coil, rotor , ignition timing etc, etc. It’s difficult to set the carbs correctly unless you have a lot of experience. Might be worth on a rolling road specialist.

 

[Cutrog1]

As the saying goes, most carb problems are electrical. Check and or replace coil, rotor , ignition timing etc, etc. It’s difficult to set the carbs correctly unless you have a lot of experience. Might be worth on a rolling road specialist.

Thanks for input but everything checked out ok on timing, dwell angle etc etc...

 

[Healey Nut]

So correct me if I’m wrong but ......you had the head skimmed (ie removed material) you bolted everything back on including the rocker shaft etc and didn’t set the rocker clearance ?
what do you think has happened to your rocker clearance by skimming the head ?

 

[Cutrog1]

So correct me if I’m wrong but ......you had the head skimmed (ie removed material) you bolted everything back on including the rocker shaft etc and didn’t set the rocker clearance ?
what do you think has happened to your rocker clearance by skimming the head ?

Misunderstanding....of course I reset the tappets. All 12thou.

So .... Today I decided to turn the slow running jet screw up one turn.....improvement!! But she now sits idling on 1000rpm.....not a real problem....but would prefer 800rpm

Not sure if it's just cos it's hot today ...I will see what happens over the next few days.
Thanks again for all being there.

 

[Madflyer]

On another Thread they showed a MOSS TEC using a vacuum gauge for timing and valves etc. READ more you may want to try it I bought a gauge on Amazon $ 22.00 comes tomorrow. I will try it on my TR6 more to come. MF

 

[Cutrog1]

As I stated in an earlier message I used both a colour flow kit and the vacuum gauge when setting up the carbs perfectly.
Currently I am allowing a couple of days to test with the slow running adjustments idling at 1000rpm....and will report back.

 

[Cutrog1]

Hey fellas! I have the answer! I took off the servo pipe from the carb inlet manifold and popped a cork in the hole. Perfect tickover....cylinder 5 and 6 fluttered when I removed the plug leads....lovely jubbly.
My friend questioned the rubber pipe I had used for the servo connection. I changed it for an old original one and following it's installation, everything perfect!!! I had mistakenly erred in my use of the wrong type of rubber hose!
Thanks to all....back on the road and running very smoothly and with grunt!