Dengie Boy Posted January 10, 2010 Share Posted January 10, 2010 Hi all I have an 87 rangerover classic fitted with a EFI V8 (early lucas flapper type) see pic below. The engine had started knocking once warm so i purchased another running V8 which i knew the history of and had even driven the rangie. I took this known good V8 and stripped it, to give it a clean, paint and replace all the oil seals. I also stripped the oil pump and fitted a new spring and overhauled the top end. Bottom end was left complete as all looked good and had previously a new cam and followers fitted. Once it was rebuilt i took the V8 out of my rangie and replaced it with the good one I rebuilt. As soon as it was replaced and all fluids checked I started it up. It took a while to start, but it started and ran but seemed like it was missing and was running a bit rough. The next day ive gone out to put a timing light on to set the timing, but now it wont start not even trying to fire. Ive checked for compression, checked all injectors and the fuel pressure with a gauge at the fuel rail, and taken out all the plugs and they are moist with the smell of petrol, so im sure its not fuel related. Ive checked the Air flow meter as per handbook and that reads ok. Ive checked each HT lead at the plug end and im getting a spark. Ive been through setting the timing, from setting the crank at the TDC mark and making sure piston no1 is TDC and the rotor arm is pointing at no1 HT lead. Ive checked the firing order of the leads and the blue cap and rotor arm look good. As the engine is being turned over the timing light is at TDC on the crank mark, but it still wont fire. I know you can be 180degrees out with fitting the distributer (which ive refitted countless times) but it cant be if the crank and no1 piston are TDC while the rotor arm points to no1 HT lead, can it?? Just spent 10hours going through all this and i still cant source why it wont fire , as compression + fuel + spark at correct time = combustion Any help or thoughts please?? Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 10, 2010 Share Posted January 10, 2010 Sounds to me like the plugs have fouled, especially if visibly wet with fuel. You could stick them in the oven at 150C for a while to dry them out properly and then re-fit, try again. Or a new set of plugs, up to you *edit* Lovely looking engine BTW Quote Link to comment Share on other sites More sharing options...
Dengie Boy Posted January 10, 2010 Author Share Posted January 10, 2010 Thanks Bowie69, but all spark plugs are new. Once i took all the plugs out to discover they were all moist with petrol, I cleaned and dried them off before putting back. I have also removed them and tested all the plugs to make sure they spark and all seem ok. Quote Link to comment Share on other sites More sharing options...
Dengie Boy Posted January 10, 2010 Author Share Posted January 10, 2010 Edit; no good looking loverly if it doesnt go! Quote Link to comment Share on other sites More sharing options...
SteveRK Posted January 10, 2010 Share Posted January 10, 2010 On the basis that you are getting fuel (as evidenced by the wet plugs) and you are getting a spark i would look the the throttle position sensor as a starting point - this is critical to proper fuelling. Plugs can get wet from over fuelling and under fuelling - it just takes longer for the plugs to get wet when a weak mixture is being fed. And then there is the cold start extra air valve that can stick open or shut. Stuck open will cause rough running as the engine warms up. Stuck shut might make it run too rich to start from cold as extra fuel is fed as a consequence of the extra air valve that is 'meant to be open' Quote Link to comment Share on other sites More sharing options...
Dengie Boy Posted January 10, 2010 Author Share Posted January 10, 2010 On the basis that you are getting fuel (as evidenced by the wet plugs) and you are getting a spark i would look the the throttle position sensor as a starting point - this is critical to proper fuelling. Plugs can get wet from over fuelling and under fuelling - it just takes longer for the plugs to get wet when a weak mixture is being fed. And then there is the cold start extra air valve that can stick open or shut. Stuck open will cause rough running as the engine warms up. Stuck shut might make it run too rich to start from cold as extra fuel is fed as a consequence of the extra air valve that is 'meant to be open' I have tried adjusting the throttle potentiometer whilst starting and been through its entire range with no difference. Also checked the extra air valve with an ohms meter and got the correct resistance so think thats ok. Thing that puzzles me is that its not even coughing, spluttering or trying to fire Quote Link to comment Share on other sites More sharing options...
Ally V8 Posted January 10, 2010 Share Posted January 10, 2010 Rover V8's are dreadful to start on wet,fouled plugs.We tend to take out 4 and crank the engine with the fuel pump disabled.Then replace the 4 plugs with any old non wet plugs to hand and try starting it.Usually it will fire up on the 4 dry plugs and then clear up and run on 8.Thats if nothing is wrong,but before you start remove the connector to the cold start injector on the plenum - its not needed. On top of my workshop woodburner there is a pile of probably 100 old plugs,hanging around for this job,I should throw most of them away - but a flooded v8 can be a pain and new plugs are expensive.BTW once its up and running on 8 you can usually refit the 4 wet ones and fire it up again to get them to clear. Quote Link to comment Share on other sites More sharing options...
paintman Posted January 11, 2010 Share Posted January 11, 2010 Take main lead off dizzy cap & hold about 6mm from block (use insulated pliers!). Turn engine over. Should be good spark. Remove dizzy cap. Hold same lead about 3mm above centre of rotor arm. Crank. Should be NO spark. Try to turn rotor arm with fingers. It should turn about 20deg. When released it should go smartly back to its original position. When resetting the timing did you make sure that the valves on No1 were both closed along with the other points you mentioned? Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted January 11, 2010 Share Posted January 11, 2010 I know you can be 180degrees out with fitting the distributer (which ive refitted countless times) but it cant be if the crank and no1 piston are TDC while the rotor arm points to no1 HT lead, can it?? Yes it can & it wont start if it is 180 out. Although you have checked that the dizzy is in the right place and the crank is TDC it still could be 180 out ........... you must also check that the valves on No1 are closed (i.e. rocking) ........ or another quick way is to turn the crank until you have the dizzy looking at no1 and the crank at TDC .......... then turn the crank through anthoer 360 degress to TDC and reset the dizzy to look at No1. simples Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted January 11, 2010 Share Posted January 11, 2010 Full flapper EFI diagnostics in the technical archive - agree it sounds like a timing misadjustment somewhere and typical RV8 fussiness over plugs. Quote Link to comment Share on other sites More sharing options...
Andrew Cleland Posted January 11, 2010 Share Posted January 11, 2010 I had a problem like this on my 110, a 3.9 with standard Lucas 14CUX injection. It was working fine, then when I came to leave work it fired-up, ran for a few seconds then died. After that I'd try to start it and it would occasionally fire on the starter, but never run. It turned-out to be the fuel pump relay being faulty - the AA man (yes, I gave up trying to fix it myself - it was cold, raining, dark and I was tired so I called them out and went for a kebab in the meantime) had a handy little tool that plugged in-place of the fuel pump relay and allowed him to manually turn the fuel pump on and off as he cranked the engine. Worked a treat to get her running again and I had a spare relay in the tool box. Anyhow, what I'm saying is suspect the electrics and particularly the fuel pump relay (and maybe you also have diode pack on the flapper system). AndyC. P.S. Engine does look nice! Quote Link to comment Share on other sites More sharing options...
j55ptk Posted January 11, 2010 Share Posted January 11, 2010 The oil pump will not self prime so will not pressurise the hydraulic lifters. You need to remove the oil pump cover and fill the gaps around the pump gears with vaseline. Do not use grease. This will prime your pump, the hydraulic tappets will open the valves and it should run as good as it looks. Quote Link to comment Share on other sites More sharing options...
Dengie Boy Posted January 11, 2010 Author Share Posted January 11, 2010 Thanks fo the replies everyone, im now going out to try again, and im not coming back until it runs paintman; tryed them suggestions but i didnt check valves were closed, as i checked that no1 piston was at the top then thought the valves must be closed. hope thats right bullbar cowboy; going to try that this evening thanks fridgefreezer; EFI diagnotics not too much of a problem as i have a workshop manual but like you said im sure its timing related. andrew cleland; checked fuel pump, relay and fuel rail pressure and injectors so 99% sure its not fuel related thanks. j55ptk; when rebuilding i filled the oil pump gears with vas to prime the pump and the first thing i checked when it started was the oil pressure thanks. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted January 11, 2010 Share Posted January 11, 2010 Incidentally, I had one of those AA handy little things to make the fuel pump run - it's called a bit of wire with a male spade terminal on each end Quote Link to comment Share on other sites More sharing options...
ramon alban Posted January 11, 2010 Share Posted January 11, 2010 Your wet plugs may have been caused by continually trying to start the engine so the cold start injector has been pumping fuel every time the engine cranks. As 'Ally V8' mentioned, a flooded engine is a pig to fire up. If so (and perchance) there may be no evidence that the fuel is coming from the normal injectors. If they are not firing, then there are three possible reason 1 the trigger signal from coil negative to the ECU has not been reconnected 2 the ECU is broken 3 the wiring loom/ECU multiplug connector is not seated or some earth connection is missing, or some other wiring loom issue. For a unique and comprehensive analysis of all the EFI components have a browse thro this archive. http://www.vintagemodelairplane.com/pages/Rover_Technical/EfiComponents01.html Quote Link to comment Share on other sites More sharing options...
meathumper Posted January 12, 2010 Share Posted January 12, 2010 I had the same problem, after a rebore and complete rebuild. In the end I found it was flooding, and ended up controling the fuel by taking the fuel pump fuse out and in and out and in at the right time, until it fired. It took me about a week of killing batterys to get it fired mind. Yes you can get the dizzy 180 out with no1 at TDC but like someone has said if both valves are closed on no1 then its right. Oh nice job on the engine. Quote Link to comment Share on other sites More sharing options...
Dengie Boy Posted January 12, 2010 Author Share Posted January 12, 2010 YES IT STARTS!!!! The problem?.............Faulty "over-run fuel shut off relay" now removed and repeatedly hit with FBH Thanks ramon, although ive got the workshop manual, ive got your page bookmarked as some useful info there Quote Link to comment Share on other sites More sharing options...
Quagmire Posted January 12, 2010 Share Posted January 12, 2010 Is a FBH the same as Land-Rover special tool No.1 ? Quote Link to comment Share on other sites More sharing options...
ramon alban Posted January 12, 2010 Share Posted January 12, 2010 The problem?.............Faulty "over-run fuel shut off relay" now removed and repeatedly hit with FBH Which I guess is pretty much the same as this suggestion: the trigger signal from coil negative to the ECU has not been reconnected Also, How was it faulty? Not responding to vacuum? Vacuum not connected? Relay contacts permanantly open? Did you destroy a good relay, one wonders? Did you replace the faulty relay or simply join the wires to bypass it? Reason I ask, is, those relays with little or no load, dont usually croak! Quote Link to comment Share on other sites More sharing options...
Dengie Boy Posted January 12, 2010 Author Share Posted January 12, 2010 Hi ramon I did test the trigger signal from the coil negative to the ECU as per workshop manual. Voltmeter between pin 1 on ECU plug and earth, crank engine and measured 6-9 volts fluctuating. This travels through pins 30 and 87 on the fuel shut off relay, so thought all ok. But looking at the wiring diagram i noticed the relay also supplies a vacuum somewhere which i couldnt locate or dont understand what it is or for, as i had a spare relay on the shelf and thought "I wonder?" Just replaced it with a known good one and hey presto it started so thought thats a faulty relay which needs attention from a FBH Dont know why this relay was faulty as all ive done is an engine swap but mighty glad its running as i thought i might of left something out from the rebuild Just to add the relay had been fitted for the past 10 years ive owned her and it was/has been covered in mud Quote Link to comment Share on other sites More sharing options...
Andrew Cleland Posted January 13, 2010 Share Posted January 13, 2010 ...i had a spare relay on the shelf and thought "I wonder?" Just replaced it with a known good one and hey presto it started Relays - the work of the devil, I wonder if Mr Lucas invented them!?! AC. Quote Link to comment Share on other sites More sharing options...
ramon alban Posted January 13, 2010 Share Posted January 13, 2010 -- looking at the wiring diagram i noticed the relay also supplies a vacuum somewhere which i couldnt locate or dont understand what it is for, as i had a spare relay on the shelf and thought "I wonder?" Just replaced it with a known good one and hey presto it started so thought thats a faulty relay which needs attention from a FBH.Just to add the relay had been fitted for the past 10 years ive owned her and it was/has been covered in mud OK! At the getgo of these systems, Bosch/Lucas had to devise a way of making a combustible mixture available when the engine was on Overrun (typically, fast downhill with throttle shut) and by using the very high vacuum generated on overrun, open a valve to allow in more metered air and thereby correct the mixture, thus averting unburned fuel popping and banging in the v. hot exhaust system. Time moved on and Rover decided to eliminate the problem in later systems, like yours, by having the vacuum operate a vacuum controlled relay to cut the engine running signal from coil neg to pin 1 of the ECU. Now with therunning signal absent, the injectors never opened on overrunn so no uncombusted fuel passed thro' into the exhaust. Same result, no popping and banging and a bonus of slight improvement in emissions and economy. Its not quite as simple as it sounds, indeed the science behind it is quite deep, but I have made a decent stab at a full explanation. Most owners dont give a damn about this but when things go wrong, as they did with you, an understanding of whats happening brings clarity to the issue - so read this study at your peril: http://www.vintagemodelairplane.com/pages/Rover_Technical/Overrun02.html Oops! Your mud covered relay had good reason to croak irrespective of its lightly loaded function. Tee hee! Quote Link to comment Share on other sites More sharing options...
Dengie Boy Posted January 13, 2010 Author Share Posted January 13, 2010 Most owners dont give a damn about this but when things go wrong, as they did with you, an understanding of whats happening brings clarity to the issue I agree about having an understanding of how/why it works, as it makes finding the fault a lot easier!! Read your article at least 10 times to get an understanding of it many thanks for you knowledge ramon. Found my vacuum switch bolted to the drivers side fuel rail with a vacuum pipe running to the back of the plenum chamber then to the fuel regulator. Quote Link to comment Share on other sites More sharing options...
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