Go Back   The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club Forums > Technical Help Forum
Register FAQ Image Gallery Members List Calendar Mark Forums Read
Notices

Reply
 
Thread Tools Display Modes
Old 11th August 2019, 13:13   #1
Barry Emmens
Newbie
 
Rover 75

Join Date: Dec 2015
Location: Trowbridge
Posts: 24
Thanks: 0
Thanked 10 Times in 4 Posts
Default V6 will not start

I have decided to hang onto my 2.5 V6 connie auto despite it still refusing to start.
Just to bring the saga up to date the vehicle was parked on the drive following a fault free run of about 20 miles and the following day cranks over but refuses to start. I have carried out the following:
New in tank filter with new seals and the modified clip fitted.
Crankshaft and camshaft sensors replaced with new components.
Fuel pump primes for approximately 10 seconds when ignition is turned on.
Fuses checked and tank half full of fuel.
Inertia switch checked and not triggered.
ECU dry.
I have checked at the schrader valve and can detect no fuel at this point and I am fairly certain that no petrol is being delivered. Whatever has broken must have happened during the trip and did not prevent the engine from running but prevents it from starting. Any other suggestions welcome.
I have one further question: Can any member recommend a company who could collect my Rover from my home address in Trowbridge and deliver it to MJN Motors in Brislington so that Mark could have a look because I am completely out of ideas.
Thank you,
Barry.
Barry Emmens is offline   Reply With Quote
Old 11th August 2019, 19:56   #2
T-Cut
This is my second home
 
Rover75 and Mreg Corsa.

Join Date: Nov 2006
Location: Sumweer onat mote o'dust (Sagin)
Posts: 21,751
Thanks: 341
Thanked 3,660 Times in 2,924 Posts
Default

Quote:
Originally Posted by Barry Emmens View Post
I have checked at the schrader valve and can detect no fuel at this point and I am fairly certain that no petrol is being delivered.
If you're certain there's plenty of fuel in the RHS (pump side) of the tank and the pump runs for several seconds with the ignition on, then logic suggests the pump itself is faulty. If the pump was pumping, the Schrader valve would exhibit a 50psi level of fuel.

You said earlier that you'd added some fuel to the tank. Was this around a litre or a larger amount? The pump has to be submerged enough to flood the priming valve or it can't pressurise nor transfer. The gauge reading isn't much help here.

TC
T-Cut is offline   Reply With Quote
Old 12th August 2019, 08:11   #3
SD1too
Doesn't do things by halves
 
SD1too's Avatar
 
Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model.

Join Date: Mar 2007
Location: Former Middlesex
Posts: 20,265
Thanks: 1,587
Thanked 3,749 Times in 3,181 Posts
Default

Quote:
Originally Posted by Barry Emmens View Post
New in tank filter with new seals and the modified clip fitted.
Hello Barry,

I know that you are convinced that the cause doesn't lie with the filter but all your evidence suggests that it does, particularly the ten second priming which is much too long.

I don't have experience myself of 'fuel filter syndrome' but others who have separated the filter housing report that it is extremely difficult to reassemble it without the seal becoming slightly displaced.

I am pleased to read that, despite your arthritis (mentioned in your earlier thread), you have succeeded in renewing the crankshaft and camshaft sensors. With that in mind, this is what I think you should do next:
  1. Place a voltmeter across the fuel pump terminals during cranking to confirm that it is obtaining a supply (as I advised in your first thread).
  2. Remove the filter canister again and slowly dismantle it, looking for anything which might cause a pressure loss in the filter. Reassemble slowly and with great care. Fit the clip.

It is easy to believe that a simple thing cannot possibly be the cause of a problem. More often than not, it is.

Simon
__________________
"Whatever is rightly done, however humble, is noble."
Sir Henry Royce.
SD1too is offline   Reply With Quote
Old 12th August 2019, 12:33   #4
Barry Emmens
Newbie
 
Rover 75

Join Date: Dec 2015
Location: Trowbridge
Posts: 24
Thanks: 0
Thanked 10 Times in 4 Posts
Default

Thank you both for your replies.
I have added 2 gallons of fuel to the tank and I have timed the priming of the pump at 3 seconds. I will check the operation of the pump whilst the engine is cranking over tomorrow. Very worried about taking out the fuel filter again and hope I don't have to.
Barry Emmens is offline   Reply With Quote
Old 12th August 2019, 14:56   #5
SD1too
Doesn't do things by halves
 
SD1too's Avatar
 
Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model.

Join Date: Mar 2007
Location: Former Middlesex
Posts: 20,265
Thanks: 1,587
Thanked 3,749 Times in 3,181 Posts
Default

Quote:
Originally Posted by Barry Emmens View Post
... I have timed the priming of the pump at 3 seconds.
That's more like it Barry!
Quote:
I will check the operation of the pump whilst the engine is cranking over tomorrow.
Thank you. You may need an assistant to turn the key as you keep your ear close to the pump. That will tell us whether or not the crankshaft sensor and pump are working.

Simon
__________________
"Whatever is rightly done, however humble, is noble."
Sir Henry Royce.
SD1too is offline   Reply With Quote
Old 13th August 2019, 09:19   #6
Barry Emmens
Newbie
 
Rover 75

Join Date: Dec 2015
Location: Trowbridge
Posts: 24
Thanks: 0
Thanked 10 Times in 4 Posts
Default

I have a feeling that I know what the reply will be but, this morning I put an AVO on the pump connections and had 12 volts for about 3 seconds whilst the pump primed and 12 volts during cranking of the engine and for a brief period when I stopped. I could clearly hear the pump humming during the priming period and for a second when I stopped. Tacho needle is moving slightly also.
Are we looking at a filter problem still.
Barry Emmens is offline   Reply With Quote
Old 13th August 2019, 10:45   #7
SD1too
Doesn't do things by halves
 
SD1too's Avatar
 
Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model.

Join Date: Mar 2007
Location: Former Middlesex
Posts: 20,265
Thanks: 1,587
Thanked 3,749 Times in 3,181 Posts
Default

Well Barry, you've replaced the camshaft and crankshaft sensors both of which have the potential to prevent the engine from starting. You've proved that the fuel pump is working and so is its relay. You have petrol in the tank yet no fuel escapes when you briefly depress the plunger in the Schrader valve.

I think the evidence points to the filter assembly don't you?

Congratulations on owning an AVO by the way!

Simon
__________________
"Whatever is rightly done, however humble, is noble."
Sir Henry Royce.
SD1too is offline   Reply With Quote
Old 13th August 2019, 15:08   #8
T-Cut
This is my second home
 
Rover75 and Mreg Corsa.

Join Date: Nov 2006
Location: Sumweer onat mote o'dust (Sagin)
Posts: 21,751
Thanks: 341
Thanked 3,660 Times in 2,924 Posts
Default

You mentioned new seals fitted as well as the Fabled Orange Clip. Did this include the thin Oring around the filter cap? The old ones certainly go stiff over the years and even a new one can fail if it becomes displaced or kinked slightly during reassembly. Here's mine (not in the fitted position for clarity):



Only a new Oring will cure this situation.
Less than 50psi fuel pressure at the Schrader valve will prevent ignition.

TC
T-Cut is offline   Reply With Quote
Old 13th August 2019, 17:16   #9
Barry Emmens
Newbie
 
Rover 75

Join Date: Dec 2015
Location: Trowbridge
Posts: 24
Thanks: 0
Thanked 10 Times in 4 Posts
Default

Yes, I fitted the complete kit which included the large thin o ring under the cover. Pretty sure that I assembled it correctly but I will check it out this week.
I have put a couple of gallons of fuel in the tank but the car is on a steep drive facing down and I am not convinced that the pump pick up is not sucking air.
There is no trace of any fuel at the schrader valve.
Barry Emmens is offline   Reply With Quote
Old 13th August 2019, 18:41   #10
T-Cut
This is my second home
 
Rover75 and Mreg Corsa.

Join Date: Nov 2006
Location: Sumweer onat mote o'dust (Sagin)
Posts: 21,751
Thanks: 341
Thanked 3,660 Times in 2,924 Posts
Default

Quote:
Originally Posted by Barry Emmens View Post
I have put a couple of gallons of fuel in the tank but the car is on a steep drive facing down and I am not convinced that the pump pick up is not sucking air.


Presumably it would usually start in that position, so I'd have expected two gallons to resolve a possible pick-up issue. Still, who knows.
With the pump verified running and sufficient fuel in the RHS there should be fuel at the Schrader valve. No fuel at the Schrader also suggests a blocked line, a blocked filter or the pump ain't pumping. None of these is likely. Leakage of the seal, however, is. But to have no fuel at all at the Schrader is unusual.



TC
T-Cut is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 17:20.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright © 2006-2023, The Rover 75 & MG ZT Owners Club Ltd