Junglie Posted November 27, 2021 Share Posted November 27, 2021 (edited) Going on from my mystery fuel leak that wasn's amystery to anyone but me... I've replaced the fuel pump on my snarling beast of a 12J. And what an utter pig of a job it was outside in the sleet. Everything is reassembled but...no start. So two questions if i may. Could someone please confirm which connector is which on top of a new(er) style mechanical fuel pump like this. Second, is there some arcane bleeding or priming I have to do? I cranked the engine with what I thought was only the suction side connected, expecting to see fuel spurt out the other side...and it didn't. Actually there's a third question as well. if there's a fuel cutoff solenoid, where would it be? Because there are a couple of loose wires flapping around, one of which I don't recognise and I'm wondering if it's come off something important... *Important(?) note* Mine does not have the insulator block shown in this drawing - just a big 6 bolt steel plate with 2 studs that the pump bolts straight on to. And the pump which came off had a different arrangement of unions on the top - they come out sideways rather than upward. Does this matter? Cheers, Simon Edited November 28, 2021 by Junglie Sensible picture Quote Link to comment Share on other sites More sharing options...
Sigi_H Posted November 28, 2021 Share Posted November 28, 2021 Don't know exactly about the 12J, but on the 11L (200 Tdi) the bleeding screw is at the top of the fuel filter housing. Not at the pump. Quote Link to comment Share on other sites More sharing options...
monkie Posted November 28, 2021 Share Posted November 28, 2021 To answer you questions: (1) I would imagine that it will follow the same style as your older pump. Put your thumb over the end to check if there is suction or not. (2) see the bleeding procedure below. (3) you require a 12v supply to the solenoid on the injection pump that is live with the ignition on. This should be a white wire. You will have air in the system from what you have described. You'll need to bleed the system, including the injection pump. It's a stupid system on the pre tdi engines as the fuel return goes via the filter which can put air back in the system. 1. Disonnect the pipe at the fuel filter that supplies fuel from the lift pump. Manually pump the hand lever on the lift pump to confirm that you get a good spurt of fuel. If no fuel, turn the engine a small amount as the Camshaft may be in the wrong position preventing you from manually priming the pump. If this doesn't work the pipe from the fuel tank to the lift pump is full of air, you can turn the engine over a few times to draw fuel from the tank. This will create a mess if the pipe is disconnected from the lift pump so be prepared or place a suitable container to catch the fuel. 2. Once confirmed, reconnect the pipe on the filter, then slacken the bleed screw on top of the fuel filter housing. Pump the lever again until you see a stream of air free diesel trickle out of the bleed screw. Close screw by nipping it up. Don't over do it or you will strip the thread. 3. Turn the ignition on to open the solenoid in the fuel injection pump. Allowing fuel to flow into the injection pump. Undo the small (8mm IIRC) bleed screw on top of the fuel injection pump. Again prime the lift pump manually until you see a stream of air free fuel coming from the bleed screw. Carefully nip up the bleed screw. 4. Again check the bleed point on top of the fuel filter. It should be air free, but double check. Now attempt to start the engine. It may take a few seconds longer than normal as it will have to clear the air out of the high pressure lines to the injectors. Quote Link to comment Share on other sites More sharing options...
Junglie Posted November 29, 2021 Author Share Posted November 29, 2021 Thanks guys. I'll try bleeding it tomorrow (and will probably cheat with a bit of suction) but... Did my question about the insulator block make sense? The replacement pump had dire warnings about reusing the insulator block (their term for the part labelled "NSS" above) and how the world would end if the pump was fitted without it. But mine didn't have the block in the first place so how could I reuse it? I'm wondering if I have actually mullered the pump - definitely should have checked the length of the actuator arms on the old and new I've also ordered an overhaul kit for the old pump now, so I'll either pop that up for sale later or simply replace the broken new one with an overhauled old one... Who said Landies were easy to live with? If I'd had a match I'd have set fire to the damn' thing yesterday. Quote Link to comment Share on other sites More sharing options...
monkie Posted November 29, 2021 Share Posted November 29, 2021 There have been some posts about this on here. It affects the stroke of the pump. Compare you new pump with the old one in terms of length of the arm that goes to the Camshaft. Quote Link to comment Share on other sites More sharing options...
Junglie Posted November 29, 2021 Author Share Posted November 29, 2021 2 hours ago, monkie said: There have been some posts about this on here. It affects the stroke of the pump. Compare you new pump with the old one in terms of length of the arm that goes to the Camshaft. Yeah, I'll do that when I've taken it off. Cheers. Quote Link to comment Share on other sites More sharing options...
Sigi_H Posted November 30, 2021 Share Posted November 30, 2021 On 11/29/2021 at 1:13 AM, Junglie said: If I'd had a match I'd have set fire to the damn' thing yesterday. Could it be that you would soon have regretted it? 😁 Quote Link to comment Share on other sites More sharing options...
Junglie Posted December 1, 2021 Author Share Posted December 1, 2021 On 11/30/2021 at 3:19 PM, Sigi_H said: Could it be that you would soon have regretted it? 😁 Probably - it's a diesel so it would have wasted the match and added to the frustration.., (I love it really. But sometimes it's just AAARRRRRGGGGHHHHH!!!!) Quote Link to comment Share on other sites More sharing options...
Junglie Posted December 5, 2021 Author Share Posted December 5, 2021 Replaced the replacement fuel pump which was broken. The actuator just flaps around and doesn't do anything. This time I used one from Allmakes 4x4 which came with the spacer and it works fine. Did everything back up. Primed the pump by hand and confirmed it squirts fuel. Yay. Put suction on the front cylinder injector, turned the key to open the solenoid and sucked until no air bubbles came through. Happy days. So why won't the bloody thing start? It doesn't even try to start. It just turns over until the battery is flat. Which is a lot of cranking... I am utterly cheesed off. I love this Landy but my God it tries my patience... I also had forgotten how revolting diesel is. Quote Link to comment Share on other sites More sharing options...
western Posted December 5, 2021 Share Posted December 5, 2021 Remove the fuel stop solenoid, extract the spring & plunger, put the solenoid body back in & reconnect the wire, then see if it starts, If it does start & run, you found s duff stop solenoid, to stop the engine you will have to stall it, Then replace the complete solenoid with a new one. Quote Link to comment Share on other sites More sharing options...
hurbie Posted December 5, 2021 Share Posted December 5, 2021 oh , and you do need the glowplugs to be hot , or it will never start with this weather ... Quote Link to comment Share on other sites More sharing options...
monkie Posted December 5, 2021 Share Posted December 5, 2021 30 minutes ago, hurbie said: oh , and you do need the glowplugs to be hot , or it will never start with this weather ... That is a very good point. If you've confirmed there is diesel coming out of the high pressure lines when you crank the engine over (assuming both timing and compression are correct), preheat is a must. The older pre-tdi diesels simply will not start without it. Quote Link to comment Share on other sites More sharing options...
Junglie Posted December 5, 2021 Author Share Posted December 5, 2021 Thanks chaps. I've run the glowplugs for about a minute - she does like a bit of pre-heating... Compression and timing should still be good as the only thing I've done is remove and replace the fuel lift pump. I did find earlier that the wire feeding the stop solenoid was broken, but I replaced that and it's good. So frustrating that all this is just a stopgap until the V8 goes in. Quote Link to comment Share on other sites More sharing options...
monkie Posted December 6, 2021 Share Posted December 6, 2021 Have you verified that the glow plugs are actually working though? Quote Link to comment Share on other sites More sharing options...
Junglie Posted December 6, 2021 Author Share Posted December 6, 2021 4 hours ago, monkie said: Have you verified that the glow plugs are actually working though? They were, and she's always been a good starter after a bit of preheat. Even after sitting around for a week or more without being run. Quote Link to comment Share on other sites More sharing options...
steve b Posted December 6, 2021 Share Posted December 6, 2021 crank it over with the injector pipes cracked off at the injectors to check flow. Bleeding this type of pump is usually done with prime lever and bleed screws on the inj. pump opened . One on rotor head and one on pump body , 8mm/5/16"AF head. Don't overtighten. Steve Quote Link to comment Share on other sites More sharing options...
monkie Posted December 6, 2021 Share Posted December 6, 2021 30 minutes ago, Junglie said: They were, and she's always been a good starter after a bit of preheat. Even after sitting around for a week or more without being run. You need to check that they are still working. Check for 12V feed at the plugs while someone holds the key in the pre heat position. Then remove each glowplugs and energise them from a 12V supply to check they glow red hot at the tips after around 5 or 6 seconds. Any that fail to glow red hot or don't glow evenly at the tip, renew the whole set of 4 with new quality ones. I use Beru. Quote Link to comment Share on other sites More sharing options...
monkie Posted December 6, 2021 Share Posted December 6, 2021 It is a simple unfused circuit on a pre TDI diesel, but there are still components that can fail, so must be checked as above. The supply from the main positive bus on the starter motor solenoid terminal goes to the ignition switch via a thick brown wire. It goes from the ignition switch to glow plug number 4 via brown with red trace. The ignition switch can fail as can the glowplugs. Be very careful not to accidentally short the glow plug terminals on the cylinder head or you will melt your wires! 1. Compression is good 2. Timing is correct 3. Fuel injectors are supplying fuel 4. Glow plugs are correctly working to pre heat. 5. Starter motor turns engine over fast enough. A 12J is a simple engine. If all of the above are true. It will fire and run. Quote Link to comment Share on other sites More sharing options...
Junglie Posted December 6, 2021 Author Share Posted December 6, 2021 It's all good advice, thanks. I know compression is good, timing hasn't been touched and the starter turns over fast enough. I tested the glow plug circuit already (though admittedly not the plugs themselves as I'm wary of snapping them). Pretty sure it's a simple (simple - ha!) problem of getting fuel to the injectors. I'm going to revisit the bleeding process and do it all a bit more methodically before anything else. Quote Link to comment Share on other sites More sharing options...
monkie Posted December 6, 2021 Share Posted December 6, 2021 5 minutes ago, Junglie said: It's all good advice, thanks. I know compression is good, timing hasn't been touched and the starter turns over fast enough. I tested the glow plug circuit already (though admittedly not the plugs themselves as I'm wary of snapping them). Pretty sure it's a simple (simple - ha!) problem of getting fuel to the injectors. I'm going to revisit the bleeding process and do it all a bit more methodically before anything else. Repeat the bleeding procedure then remove the high pressure pipes from the injectors and get someone to turn the engine over as you watch for fuel coming out of the pipes. Quote Link to comment Share on other sites More sharing options...
Junglie Posted December 6, 2021 Author Share Posted December 6, 2021 2 hours ago, monkie said: Repeat the bleeding procedure then remove the high pressure pipes from the injectors and get someone to turn the engine over as you watch for fuel coming out of the pipes. Exactly what I was planning to do, but great validation, thanks. Quote Link to comment Share on other sites More sharing options...
Junglie Posted December 7, 2021 Author Share Posted December 7, 2021 This is driving me effing insane. Go back and do it all by the book: Crack banjo on top of the fuel filter and pump the little lever. Lots of fuel comes out. Crack bleed nipple on DFS pump. Turn key to open solenoid and pump the little lever. It's like opening an artery. Crack unions on injectors one at a time and pump. Fuel leaks out. Remove a glow plug and turn it to pre-heat for 30 secs. It's bloody hot. Pop a boost pack on the battery for good measure and crank it over, cos it has to start, right? Nope. Squirt some easy start down the intake (I know, but I'm getting desperate) and try again. It fires two or three times and then nothing. I know I'm taking this lump out and replacing it woth a V8 but I haven't had time to do everything I need to first and I need the damn' thing working! I'm tempted to ring the RAC and tell them it won't start but it isn't taxed or MOT'd and they might get shirty about it. I'm also tempted to ring a local garage and get them to come and take it, fix it and MOT it all at the same time, but that really goes against the whole ethos of having a Landy in the first place. @monkieI've followed your advice and I'm still stumped. Gentlemen (and ladies if there are any here) I am open to just about any suggestion right now. Quote Link to comment Share on other sites More sharing options...
monkie Posted December 8, 2021 Share Posted December 8, 2021 Okay, so just to confirm: 1- you have bled the fuel system as described and confirmed there is air free fuel in the system. 2- you have confirmed that fuel is being pumped to the injectors by slackening the high pressure pipes at the injectors as someone cranks the engine over. 3- you have confirmed 12V is supplied to the glowplugs as someone holds the key in the preheat position. 4- you have removed all 4 glowplugs and energised them to confirm they glow (visually red/yellow hot) uniformly at the tips. Are all 4 points true for your check list? Quote Link to comment Share on other sites More sharing options...
Junglie Posted December 8, 2021 Author Share Posted December 8, 2021 4 hours ago, monkie said: Okay, so just to confirm: 1- you have bled the fuel system as described and confirmed there is air free fuel in the system. 2- you have confirmed that fuel is being pumped to the injectors by slackening the high pressure pipes at the injectors as someone cranks the engine over. 3- you have confirmed 12V is supplied to the glowplugs as someone holds the key in the preheat position. 4- you have removed all 4 glowplugs and energised them to confirm they glow (visually red/yellow hot) uniformly at the tips. Are all 4 points true for your check list? Yep, though I think I may need to do #2 again before I give up as I was working solo, which isn't ideal. Quote Link to comment Share on other sites More sharing options...
steve b Posted December 8, 2021 Share Posted December 8, 2021 If you have diesel and no air out of bleed screws , tighten up and slacken one injector pipe at the injector and crank over , once diesel starts coming out they will often fire and run on the other three Steve Quote Link to comment Share on other sites More sharing options...
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