LCJ Posted March 23, 2013 Share Posted March 23, 2013 Hi folks My 300tdi has developed a problem. It will idle happily at start up. If I then drive a few hundred metres down the road and change up the gears the power drops off until eventually the engine cuts out. If I stop the vehicle before it cuts out the idle is rough but recovers to normal soon enough. However, if I rev it it revs up fine but then coughs once at the end of overrun. If I start the vehicle on the drive way, don't move it but rev it it works fine. The fact it's idling normally makes me think its the fuel pump but can anyone else suggest anything else? Thanks all! Quote Link to comment Share on other sites More sharing options...
LCJ Posted March 23, 2013 Author Share Posted March 23, 2013 Ps timing is fine - belt replaced c.3000 miles ago and done then Quote Link to comment Share on other sites More sharing options...
steve b Posted March 23, 2013 Share Posted March 23, 2013 How new is your fuel filter ? In this cold weather any water in the filter may freeze and partially block it , either that or as you say the lift pump is failing cheers Steveb Quote Link to comment Share on other sites More sharing options...
TheRecklessEngineer Posted March 23, 2013 Share Posted March 23, 2013 In this order: Fuel filter, Lift pump, Fuel lines. Replace the fuel filter first, then when it's running after the change crack the bleed screw on the top of the housing. If it's a good solid 'pulse' of diesel you're all good. Otherwise, suspect the lift pump or the fuel lines. Quote Link to comment Share on other sites More sharing options...
LCJ Posted March 25, 2013 Author Share Posted March 25, 2013 Thanks for the help chaps. Am attempting to change the lift pump now but cannot for the life of me get the new pump anywhere near enough to the block to get the bolts in. I've tried turning the engine over slightly but to no avail. Is there a secret to getting the wretched thing to fit? Thanks all Quote Link to comment Share on other sites More sharing options...
western Posted March 25, 2013 Share Posted March 25, 2013 is the new lift pump identical to the existing one ? is there a thick black plastic spacer block on the old pump ? or a raised area on the plate it bolts to on the engine. cam lobe maybe preventing it bolting up, turn engine so the lobe high point is facing inwards to engine centreline, the pumps need a good push to get the bolts started IIRC. Quote Link to comment Share on other sites More sharing options...
LCJ Posted March 25, 2013 Author Share Posted March 25, 2013 Pump certainly looks identical, no spacers or raised bits on old or new. Have tried moving the cam round but no joy. I can get the pump lever in with the pump flush to the block but sat too high up,but when I push the pump down to line up the bolt holes the pump is pushed away from the block.. Quote Link to comment Share on other sites More sharing options...
western Posted March 25, 2013 Share Posted March 25, 2013 sounds like the operating arm that the cam works is holding the pump off, the bolts should be long enough to get them started then as you tighten the bolts it should all pull together. Quote Link to comment Share on other sites More sharing options...
TheRecklessEngineer Posted March 26, 2013 Share Posted March 26, 2013 As far as I recall, you need to be fairly brutal to get them together. As you tighten it up the arm compresses the spring inside the pump. Quote Link to comment Share on other sites More sharing options...
Frax Posted March 26, 2013 Share Posted March 26, 2013 Are you sure you are not trying to force the pump leaver to the wrong side of the cam ? Quote Link to comment Share on other sites More sharing options...
LCJ Posted March 26, 2013 Author Share Posted March 26, 2013 Thanks for all responses,am going to attack it again tomorrow and try using the bolts to tighten things up. Lever goes on top of the cam, right? (according to Haynes book of lies and the how-to on here at least) Quote Link to comment Share on other sites More sharing options...
western Posted March 26, 2013 Share Posted March 26, 2013 lever just sits against the cam, not on top or inside. Quote Link to comment Share on other sites More sharing options...
steve b Posted March 26, 2013 Share Posted March 26, 2013 (edited) Yep , if you get one bolt started by allowing the pump to rock over at a slight angle then straighten it up to get the second one started then wind them in gentle and even it should seat to the gasket with just the spring pressure of the arm , the bolts are a bit short , hence the rocking to one side edit to add I think the point of contact for the lever is around 11o'clock on the cam Ralph cheers steveb Edited March 26, 2013 by steve b Quote Link to comment Share on other sites More sharing options...
LCJ Posted March 27, 2013 Author Share Posted March 27, 2013 It works! Got the pump fitted (who designed such awkward access to them!?) turned they and it started after a few splutters but now it drives superbly. Thanks to all who responded - ver much appreciated with donation to forum on the way Quote Link to comment Share on other sites More sharing options...
western Posted March 27, 2013 Share Posted March 27, 2013 good to read you got a good result. Quote Link to comment Share on other sites More sharing options...
steve b Posted March 28, 2013 Share Posted March 28, 2013 good to hear Cheers Steveb Quote Link to comment Share on other sites More sharing options...
LCJ Posted March 31, 2013 Author Share Posted March 31, 2013 Spoke too soon! Symptoms are worse than ever now. Sounds like its missing and has flat spots. Fuel lines seem fine, so any more suggestions please?! Quote Link to comment Share on other sites More sharing options...
steve b Posted March 31, 2013 Share Posted March 31, 2013 ...it could be a faulty new pump, it does happen. With it ticking over crack the bleed screw on top of the filter , a good healthy squirt shows the fuel pump/lines etc are ok If that checks out , maybe check the air intake/filter etc , hoses can delaminate inside. cheers Steveb Quote Link to comment Share on other sites More sharing options...
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