How to fit a rubber bulb primer into a metal fuel line?

Refueler said:
The only bit I will concede on this - we use setups that usually do not have pumped fuel lines. EG - my Perkins has a tank that in use - the mid level is about level with the fuel filter on engine ... so its gravity fed and when fuel is low - its drawn by the engine mounted 'lift pump' ... there not being any pump in the tank.
But most cars have a pump at the tank to feed the system.
Also the car usually stays reasonably level unlike a boat that can roll / pitch etc.
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It's not as common as it used to be to have primer bulbs on cars, because more and more are fitted with electric pumps in the tank, as you say. Some years ago, many cars did not have an electric pump in the tank, the lift pump was built into the high pressure injector pump body. Without the primer pump these were generally impossible to bleed. It's funny, reading some of the posts here, to think that the horizontally mounted primer bulbs on older cars used to manage to suck diesel almost the full length of a car, from a tank under the boot floor, up and over the inner wing and deliver it to the injector pump. Yet, once fitted to a boat, it won't draw fuel a few feet, more often than not downhill, unless it's mounted in a specific orientation, fitted with fire proof covers and indestructible fuel lines.

It's also worth noting, that probably the biggest factor determining how the valves in the primer bulbs operate, is the operation of the pump itself. As you mentioned earlier, the fue in the bulb will force the valves to open and close.
 
Mercury Rising said:
Motor manufacturers use spring clips, on hose, on metal pipes. And all vehicles use high pressure fuel systems these days.
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But the hoses and spring clips are only used on the low pressure side of the fuel system. Anything after the high pressure pump will be either metal, or crimped hydraulic type hose.
 
PaulRainbow said:
It's not as common as it used to be to have primer bulbs on cars, because more and more are fitted with electric pumps in the tank, as you say. Some years ago, many cars did not have an electric pump in the tank, the lift pump was built into the high pressure injector pump body. Without the primer pump these were generally impossible to bleed. It's funny, reading some of the posts here, to think that the horizontally mounted primer bulbs on older cars used to manage to suck diesel almost the full length of a car, from a tank under the boot floor, up and over the inner wing and deliver it to the injector pump. Yet, once fitted to a boat, it won't draw fuel a few feet, more often than not downhill, unless it's mounted in a specific orientation, fitted with fire proof covers and indestructible fuel lines.

It's also worth noting, that probably the biggest factor determining how the valves in the primer bulbs operate, is the operation of the pump itself. As you mentioned earlier, the fue in the bulb will force the valves to open and close.
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I am going to risk being ridiculed now ....... but an ex girlfriend of mine ran out of fuel and I sorted a few gallon into her tank to get her going.
How did I get the fuel from tank to engine ? Believe it or not - and I swear this to be true ... I took a clean rag .. bunched it up round the tank filler ... pressed lips hard on and blew like hell into the tank ... Couple of goes at that and engine fired up ...
 
VicS said:
Because the little valves are not sprung,. They rely on gravity to make them fall closed on to their seats
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Yeah, I've got a siphon like this, the bulb has to be vertical to get the siphon going.

It might just be the spring is knackered in the valve, but that's how it works.
 
Sorry. My mistake. There was another thread about a T piece to a heater.
However, his fuel line will be low pressure so regular fuel line clips, as used by the motor industry will be perfectly correct.
The other suggestion for a barbed tail will introduce two extra olive joints into the system, which themselves could be subject to failure.
 
Mercury Rising said:
Sorry. My mistake. There was another thread about a T piece to a heater.
However, his fuel line will be low pressure so regular fuel line clips, as used by the motor industry will be perfectly correct.
The other suggestion for a barbed tail will introduce two extra olive joints into the system, which themselves could be subject to failure.
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No problem. We seem to have some sort of misunderstanding, i have already suggested fuel line clips and even recommended the first ones in your post #3
 
On some engines (eg my Perkins 4108) the lift pump, primary filter, secondary filter, injection pump priming bolts etc are all most unconveniently spread all around the engine: in these cases it is quite useful to have an OB priming bulb with long rubber "arms", so one can move the bulb and pump from positions all around the engine body
 
Roberto said:
On some engines (eg my Perkins 4108) the lift pump, primary filter, secondary filter, injection pump priming bolts etc are all most unconveniently spread all around the engine: in these cases it is quite useful to have an OB priming bulb with long rubber "arms", so one can move the bulb and pump from positions all around the engine body
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The 4-107 priming is useless ... its a thin lever job that supposedly operates the lift pump. I've used it in the past and even disconnected pipe to see if it 'squirts' .... ZERO !!

I must fit a priming bulb !!
 
Roberto said:
On some engines (eg my Perkins 4108) the lift pump, primary filter, secondary filter, injection pump priming bolts etc are all most unconveniently spread all around the engine: in these cases it is quite useful to have an OB priming bulb with long rubber "arms", so one can move the bulb and pump from positions all around the engine body
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Thanks.

I'm looking at fitting a bulb to a 1967 BMC Commander engine.

Your 'wandering lead' type of thing could be very useful.
 
Refueler said:
The 4-107 priming is useless ... its a thin lever job that supposedly operates the lift pump. I've used it in the past and even disconnected pipe to see if it 'squirts' .... ZERO !!

I must fit a priming bulb !!
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That's exactly the situation with my (2) BMC Commander engines.

Trying to bleed with the lift pump lever is a waste of time.
 
NealB said:
That's exactly the situation with my (2) BMC Commander engines.

Trying to bleed with the lift pump lever is a waste of time.
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I was told by an engineer - the the lever only works at a certain position of the engine stroke .. that you need to turn engine till you feel the lever has resistance ...

Tried that .... still zero !!!
 
Refueler said:
I was told by an engineer - the the lever only works at a certain position of the engine stroke .. that you need to turn engine till you feel the lever has resistance ...

Tried that .... still zero !!!
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Oh yes .... I know that one, and, just like your Perkins, my old BMC's don't respond to a slight rotation with the starter.
 
As the lift pump is driven from the camshaft the cam driving it could be 180 degrees out (ie. the cam lobe could have lifted the pump lever. The cam rotates at half engine speed)

so most handbooks could have a warning such as this from the Perkins 1000 series engines.

Operate the hand priming pump located on the bottom of the fuel lift pump on the engines' right side. Note: If the priming pump does not function it is possible the cam lift lobe is up. Turn the engines crankshaft one full turn clockwise. Retry priming pump.
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Mercury Rising said:
As the lift pump is driven from the camkshaft the cam driving it could be 180 degrees out (ie. the cam lobe could have lifted the pump lever. The cam rotates at half engine speed)

so most handbooks could have a warning such as this from the Perkins 1000 series engines.
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Yes .... I think every boat I've had (and there's been quite a few now), has had that sort of advice in the engine handbook.

(Well ..... except for the: Heron, National 12s, Solo and Supergrad)
 
NealB said:
Yes .... I think every boat I've had (and there's been quite a few now), has had that sort of advice in the engine handbook.

(Well ..... except for the: Heron, National 12s, Solo and Supergrad)
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I think I learnt this when I was about 12. Some people obviously take a bit longer.
 
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