3.9 v8 Discovery wont start....

[LANDYTIM]

Parked it up on Friday night to do the brakes. Did those tried to start it no luck...

Its got a spark to all plugs. They all had petrol on when pulled out. WOnt even fire....  :x

Any ideas anyone?

Cheers

[LANDYTIM]

still not started, had a mate look and he said it could be flooded so pulled out plugs, squirted a bit of oil down the bore and....... still not starting....

[J.D.]

Timing belt snapped?

[LANDYTIM]

Nop ive been over everyting I can think of (not that im a mechanic by any means!)

There is nothing obvious. I only parked her up and put on new discs and pads at the front!

[J.D.]

Ok, i don't know what you have checked so I will start from the beginning:

Plugs, dizzy, coil, rotor arm, fuel pump, leads, timing belt, air flow meter, the fuel cut out button under the dashboard on the drivers side.

[LANDYTIM]

Plugs, dizzy, coil, rotor arm, fuel pump, leads, timing belt, air flow meter, the fuel cut out button under the dashboard on the drivers side.

plugs cleaned and back in, good as new. all plugs sparking fine. coil obv ok. new rotor arm. fuel on plugs and can hear fuel pump go when ignition is turned on. new ht leads on yesterday. timing belt ok. air flow meter discon and tried, no change. the recon no change. HOWEVER, I cant find the fuel cut out button, but would fuel pump go if it had cut out??

Cheers

[Rossko]

I think the fuel cutout is on the engine side of bulkhead, passenger side.  But no,pump would not run if it had tripped.
Check voltage at coil +ve when cranking, you want more than 9V.  Less than that suspect immobilliser spider or body earth straps

[andrew2986]

Hi,

Any luck yet?

where are you in essex ?

If you need someone else to help stare under your bonnet give me a shout, im off with the kids this week (half term) Mine is a 97 V8, happy to pop over if its not to far

Andy

PS

on mine the fuel cut off button is behind the washer bottle on the bulkhead, but, as Rosko said the pump wouldnt run if it was off.

[Thrasher]

I hope you timing belt isn't "ok" .... 'cos the 3.9 has a timing chain ;-)

Check coil - mark sure you are getting a good fat spark, not a weak one.

This one is worse, your alarm spider has died. You can bypass it by jury rigging up the coil to the battery......

[LANDYTIM]

Had a mechanic friend look at it yesterday and he said it may just be flooded. Did as he said and she fired but the battery is now dead from keep turning it over! Is it likely that it is this?

[andrew2986]

its possible, can you not jump it from another car ?

[LANDYTIM]

Hoping for a jump pack to turn up. No other cars here at the moment Mums away for two weeks, very luck due to the fact there is a Discovery stranded in her back garden!! :twisted:

[J.D.]

Speaking from experience I have yet to find a jump pack which is able to turn over a Land Rover for any length of time mate, they don't seem to have the cranking amps in them.

[DoubleTop]

When I first got mine, the battery was dead, rather than buy a new battery for something that might have been a waste of time, I got a jump pack as at least I could use it for other things.  I could start mine 10-15 times using the pack, and put some air in the tyre that kept going flat.  Mines a Black and Decker something or other with a air compressor.

DT.

[LANDYTIM]

had another play a minute ago and she will now fire but pops back though the air filter.....

[J.D.]

Sounds like a dropped valve or a loose tappet mate. Mine unscrewed a tappet adjuster not long ago and had those symptoms.

[LANDYTIM]

Lucky its a Land Rover or it would be gone by now. What should my next step be?

[J.D.]

Take the rocker covers off and check the tappets. Im not that familiar with V8s as I am with diesels but I assume it would be relatively similar.

Just check there isnt a loose / snapped tappet. If there is, tighten it up to the specified clearance and / or replace it and it should be fine. If not, its a head off job.

I beleive the air flow meter can sometimes cause this problem, but like I said, im not too hot on the LR petrol engines.

If you want a better explanation, feel free to bell me at the workshop - 0772 508 5775.

[LANDYTIM]

GOING TO DROP ALL THE OIL AS WHAT IS IN THERE NEEDS CHANGING AND I9S TOO THICK ANY WAY. COULD THIS HAVE CAUSED THE VALVES TO STICK?? ALSO CANT GET THE DRAIN PLUG OUT THE SUMP, ANYONE KNOW WHAT SIZE IT IS? 28??

[hairyasswelder]

Timing belts, adjusting tappets????? Only on Diesels  :-.

Try sneaking this into Range Rover section, more V8's in there  :?

 :-k the sump plug is either 24 or 27mm, cant remember which but 28mm is not a standard size,

If a tappet has failed then you need a new hydraulic lifter, yes the oil can make a difference.

How was it running before it failed to start?
Have you changed/altered anything?
Plug leads all back on correctly?

[burgerman]

 Had similar issues when i had mine, turned out to be the temp sensor for the cold start,   Basicly was dumping in tooooo much fuel and flooding without even firing, a very short tow got it going most times till i worked it out and changed the sensor,   Just a thought  :-k

[LANDYTIM]

Its an auto so I cant even give it a little tug down the road! Nothing was changed engine wise between it being turned off and not starting. The only thing I did was change front discs and pads..... Will take a look in the Range Rover section.

[LANDYTIM]

Couldnt get the sump plug out so had to drop the whole sump, drill the plug, insert bolt and wind out (with the help of a 4ft bar!)

Going to remove rocker covers aswell. Gaskets leaking so another job done too!

Got new steering damper aswell as old one was <edit>

Going to change all oils and filters.

Then hopefully by then I may have found the problem!

[trecfive]

Have you been stop-starting the car over a short period without letting it get up too working temperature?. If so you have flooded it, plane and simple. The cure, remove all the plugs , heat them up with a blowlamp or put them on the gas ring on the cooker(you can then remove two at a time and they stay relatively warm) replace all eight, a charged up battery ,and it should fire up, run lumpy for a while then even out to that nice v8 burble. If it was running nice before,it should still  run nice now. How do i know? been there before.

[LANDYTIM]

Just changed the oil to see if its any better. Sump plug was rounded so had to remove sump and get bolt out. Can anyonw tell me what torque the sump bolts and drain plug should be? Can see it in the Haynes!  :roll:

Cheers
Tim

[Budgie]

Never used a torque setting on a sump plug. Just nip it up until it seats properly, undo it again if you're not sure as it should come off with a normal spanner.

As you've replaced the ignition leads since this all started, make sure they are going to the right cylinders. The backfires through the air filter could be caused by the plug in one cylinder sparking while in the inlet valve is open, meaning you have the wrong ignition lead on it.  ;)
Pull all the leads off the dizzy cap and start again, referring to your Haynes Manual for the correct location of the leads on the dizzy cap.

[LANDYTIM]

Ok ill check the leads, we replaced them one at a time to avoid a wrong l#ead but I will check anyway!

Tim

[J.D.]

Timing belts, adjusting tappets????? Only on Diesels  :-.

Did say I wasn't familiar with V8s. I've worked on one and that was only to replace the water pump, all the trucks I work on are diesels.

[hairyasswelder]

Timing belts, adjusting tappets????? Only on Diesels  :-.

Did say I wasn't familiar with V8s. I've worked on one and that was only to replace the water pump, all the trucks I work on are diesels.

Thought so  ;) wasnt knocking you but 90% of disco's are diesels, thats why I said try Range rover section as 90% are V8's  ;)
(90% is a rough number not an exact figure  ;) )

[LANDYTIM]

Have you been stop-starting the car over a short period without letting it get up too working temperature?. If so you have flooded it, plane and simple. The cure, remove all the plugs , heat them up with a blowlamp or put them on the gas ring on the cooker(you can then remove two at a time and they stay relatively warm) replace all eight, a charged up battery ,and it should fire up, run lumpy for a while then even out to that nice v8 burble. If it was running nice before,it should still  run nice now. How do i know? been there before.

How long should the plugs be heated for with a blowlamp?