New at this so please bear with me for the explanation.
The car's done 180k but over the last 40k is been progressively difficult to start needing several turns before firing, otherwise runs fine. Of late I have to pump the fuel primer bulb to get it to go. OK to start inside of 1hr after initial start otherwise back to the bulb.
I think its either getting air into the fuel or the pressure in the fuel system is able to fall when not running thus being a dog to start as the pump is initially starved. There is no fuel leak, any fuel smell nor can I hear any hissing noises after priming the bulb until its hard.
Its had a new primer bulb in case the one way valve was leaking, it wasn't.
I did read through the forums threads on cold starting, while interesting I'm confident its not battery, plugs etc.
Any ideas would be very much appreciated.
cheers
Edited by Dynamic Dave on 22/12/2009 at 01:06
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I assume by your description that this a diesel! If pumping the primer improves the starting then you must have air getting in somewhere. If its a Bosch pump, leaking injector return pipes can allow air in as for some inexplicable reason they are connected to the flow rather than the return.
Leakage in the fuel system wil not show up as escaping fuel as the whole system is under vacuum - except the afformentioned leak off pipes, they can appear wet. Have you changed the fuel filter recently, if not that can obstruct the fuel flow especially when the weather is as cold as it is now.
Faulty glow plugs will show as, difficult starting, clouds of white smoke when started and misfiring for the first 20 or 30 seconds.
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19? and the correct year is?
DD.
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Thanks for the replies
Sorry DD.... its 1993.... and yes Pete you guessed its a diesel, with a Bosch!
The glow plugs are not new, probably 80k old. I read you can test by removing and connecting across a battery but also read that that test didn't necessarily prove anything. Any views?
It does puff some white smoke on starting and can be quite 'lumpy' when initially fired from cold, I always figured that was just an old diesel thing.....may be an old diesel waiting for new glow plugs eh!
When I looked previously the no.1 injector top connection did look wet but didn't seem to smell much like diesel so figured it was just condensation/damp. If you can suggest a test for the glow plugs I'll do that and check for leakage at the same time. Assuming the pipe itseld isn't leaking and its a joint what it best to fix with?
Ref the leak off pipes - for a novice - once presssurised is the leakage pipe connected somewhere to the low pressure side otherwise where does the fuel/pressure go if not leaking out?
Many thanks
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You can test the plugs in situ but you need to take the links off, you only need to disconnect two two enable you to test them individually. You need a meter set to the 'ohms' range, connect it between the terminal and earth of ach one, you should get a reading of one ohm or less. If you don't have access to a meter, connect a piece of fairly thick wire to the battery + terminal and touch it on each plug terminal in turn, you should get a reasonable sized spark, no spark= duff plug.
The leak off pipes are connected to the inlet side of the pump, so when the engine is stationary if air leaks in it allows the fuel to run back to the tank.
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Hi Peter and Dynamic Dave
Thought you deserved an update. it's fixed thanks to your suggestions!
Given I could not find any fuel or air leaks I went for the easier option of testing glow plugs. Two provided no continuity/ohm test at all so I took them out (fortunately they were the easy middle two) and tested again across a battery... neither worked. Two replacements later and she starts fine. The initial smoke on start has now hugely reduced as has the lumpy misfiring like sensation.
With hindsight I think i was getting distracted by the fact that pumping the primer bulb did make it better hence thought it was a fuel problem. I reckon for whatever reason it helped when only one glowplug had gone but with two gone it didn't but I was already convinced it was a fuel related problem.
Anyway job done with little expense.
Thanks very much
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