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Ray Zeffert
New User
Username: rayzef

Post Number: 7
Registered: 4-2006
Posted on Thursday, 16 October, 2014 - 07:32 pm:   Edit PostDelete PostView Post/Check IP

Hi All, need help please
V8 was misfiring, would not start. I had the car on the dyno showed hi resistant leads, so all leads and plugs were replaced.Plugs were burnt. Compression test showed all is OK, back on the Dyno and all was well. After a week would not start and still misfires and torque non existent!
Any help would be welcome as cannot think of anything else to renew, points are OK.
Thanks
Ray Z
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Bob uk
Unregistered guest
Posted From: 94.197.122.78
Posted on Friday, 17 October, 2014 - 05:53 am:   Edit PostDelete PostView Post/Check IP

Were the plugs white.

Should be coffee coloured.

Check fuel pump ticks when the iignition is turned on. If not tap steel body of pump with a screw driver handle.

If pump ticks then remove carb dash pot and look for Petrol in main jet with bright light. No fuel means usually stuck float. Tap float bowl with handle. Not likely that one stuck float will stop engine from starting but will cause no power.

I assume by dyno you mean electronic tuning equipment with an ossciloscope, and not roller driven by the rear wheels to show horsepower.

If the ignition system has been repaired/serviced properly using electronic tunning equipment then I assume the no start must be fuel. However check the ballast resistor for the coil.

An easy check is to squirt a bit of petrol down the intake by opening the choke flap and squirting. Allow choke flap to shut then start engine if the engine fires and runs momentarily then it's fuel that is the problem.

Warning never squirt petrol into an engine while being cranked. Before cranking the engine move the petrol container well away from the car. Do not throw petrol into the choke, careful squirt it in. Do not leave rags in the valley of the engine if petrol is spilt. Be very careful.

(Message approved by david_gore)
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Paul Yorke
Grand Master
Username: paul_yorke

Post Number: 1286
Registered: 6-2006
Posted on Friday, 17 October, 2014 - 02:39 pm:   Edit PostDelete PostView Post/Check IP

If you are getting fuel up . . .

Condenser. New ones can be bad out of the box, so watch out for that.

Carbon centre contact in cap missing.

Distributor BOB weights seized / seizing.

Are you getting good sparks at the plugs?
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Bob uk
Unregistered guest
Posted From: 94.197.122.92
Posted on Saturday, 18 October, 2014 - 05:36 am:   Edit PostDelete PostView Post/Check IP

Bob weights for an advance.

(Message approved by david_gore)
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Ray Zeffert
New User
Username: rayzef

Post Number: 8
Registered: 4-2006
Posted on Saturday, 18 October, 2014 - 01:25 pm:   Edit PostDelete PostView Post/Check IP

Thanks for all the tips on what to check. Booted over quicker after initial failure, got the motor hot and it never missed a beat, idles OK. All pumps and carbs working fine. Will take for a drive Sunday and see if the problem returns, it could be valve stem seals as it was standing for a long time, will keep fingers crossed.
Thanks again for the help
Ray Z
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Ray Zeffert
New User
Username: rayzef

Post Number: 9
Registered: 4-2006
Posted on Saturday, 25 October, 2014 - 07:50 pm:   Edit PostDelete PostView Post/Check IP

Hi All
It turned out to be a simple answer, fresh fuel! The fuel in the tank was at least 12 months old. The engine ran very smooth after the re-fill but still lacks power going up hills, so that is the last part to solve. Never thought of old fuel, such a very simple answer.
Ray Z
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Jan Forrest
Grand Master
Username: got_one

Post Number: 689
Registered: 1-2008
Posted on Saturday, 25 October, 2014 - 09:48 pm:   Edit PostDelete PostView Post/Check IP

You don't indicate what part of the world you live in, but I'm guessing that it's a bit warmer than the UK. A couple of years ago I bought a small convertible that had been stood unused for at least 4 years which I trailered home. After fitting a newer battery (actually a small old mobility scooter battery) it started first turn of the key to reveal that the tank was round 3/4 full.

However our Summers had been less than brilliant during that time, so few of the lighter components had evaporated. As the car wasn't going to be used for a couple of months I drained nearly all of it and chucked it into the Shadow. It ran normally, just as the convertible had.
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Ray Zeffert
New User
Username: rayzef

Post Number: 10
Registered: 4-2006
Posted on Friday, 07 November, 2014 - 08:46 pm:   Edit PostDelete PostView Post/Check IP

Jan I live in Australia, the fuel lasted 10 months!
Since my last email the fuel pump failed and was burntout at one end. We have installed a SU pump which was a direct replacement. The only problem is finding the Points Syc tool, seems like the 8 cylinder version is not available but the 6 cylinder is!
It was close to 40c today but next week seems cooler so will try new pump up hill to see if it improves the torque.
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Bob uk
Unregistered guest
Posted From: 94.197.122.93
Posted on Saturday, 08 November, 2014 - 06:21 am:   Edit PostDelete PostView Post/Check IP

Ray

check the filter in the tank and the filter before the pump near the tank.
These filters are very good at filtering so good that they block up.
Refer to manual for instructions. These filters get overlooked at service time.

(Message approved by david_gore)
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Ray Zeffert
Experienced User
Username: rayzef

Post Number: 11
Registered: 4-2006
Posted on Wednesday, 12 November, 2014 - 11:40 am:   Edit PostDelete PostView Post/Check IP

Bob
Thanks, went the whole hog, tank was removed, cleaned and all new filters installed if needed. We will take the Cloud for a run through the hill Thursday to test the new pump. Then will fit electronic ignition, to complete the rebuild. Only a re-wire where needed, leather and paint to go!!
Ray Z
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Bob uk
Unregistered guest
Posted From: 94.197.122.76
Posted on Thursday, 13 November, 2014 - 06:35 am:   Edit PostDelete PostView Post/Check IP

The filter in the tank that is attached to the drain plug is a simple mesh that can be washed out. The next filter is a desposable element that is changed. If the petrol you are using is clean then this filter is probably unnecessary. I assume that the SU pump filters are clean because you have repaired it. The carbs have filters where the fuel enters the float bowl.

It is important for the correct operation of the pump that the filters on the suction side are free flowing and that any rubber pipes in the suction side are not collapsing or the insides falling apart. Use hose marked sae fuel. Originally RR used Smith's petro flex which is hard and expensive to get and wasn't that good.

I would hang fire on electronic ignition because if the dizzy is ok and set right the only advantage will be not having to set the points every 12000 miles. The car won't run better or use less fuel because of electronic ignition.

However if the dizzy is worn electronic ignition accepts wear better than points within limits that is.

Remember that spark plugs just light the fire, and do not make power. However some people will suggest that stronger sparks make more power.

My dizzy (shadow 1974) is blessed with a single points which means only one set to buy. I think yours has two sets to split the dwell. My points were fitted in 1986 and apart from an odd file up and dwell setting up have never failed.
the advocates of electronic ignition will quote how reliable electronic is in comparison to points which is true but it is not that wider gape. Plus electronic ignition does fail and when it does it is difficult to repair especially at the side of the road. Whereas points can be fixed with minimal test kit and tools. I keep a finger nail sand paper stick in the car.

(Message approved by david_gore)
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Mark Taxis
Frequent User
Username: mark_taxis

Post Number: 78
Registered: 4-2007
Posted on Friday, 14 November, 2014 - 06:38 pm:   Edit PostDelete PostView Post/Check IP

On the subject of old fuel, I had the same problem with my MK6 it had only 1/4 tank of fuel and had been sitting idle for about 3 months, it refused to start, after much mucking around I drained the tank and refilled with fresh fuel problem solved.
I was talking to the local garage and he informed me that the unleaded starts going off after 2 weeks but the high octane (95 &98) has a 6 month shelf life. Since then I have always made sure that the tank is left full of the higher octane fuel if the car is not going to be used for some time.
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Jan Forrest
Grand Master
Username: got_one

Post Number: 698
Registered: 1-2008
Posted on Friday, 14 November, 2014 - 10:10 pm:   Edit PostDelete PostView Post/Check IP

On the subject of 'stale' fuel. Once again I've bought an old vehicle (a small 2-stroke motorcycle) that has been stood for over 3 years. It starts and runs on the old fuel and oil that have been in the tanks since it was taken off the road.
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Paul Yorke
Grand Master
Username: paul_yorke

Post Number: 1316
Registered: 6-2006
Posted on Saturday, 15 November, 2014 - 06:31 pm:   Edit PostDelete PostView Post/Check IP

Fuel definitely makes a difference and does go stale.

It is also one of the easiest things to change and eliminate as a cause. If you are too tight to waste it, feed it back into the tank a gallon at a time once you have the car running properly, or use it in your 2 stroke mower. I use it in our steam cleaner.

I hate old fluids, lubricants, and fuel and are the first things changed when recommissioning RR&B cars. IMHO it's just plain foolish not to.

We've had lots of vehicles in over the years which have come out of storage and the owners or other garages 'have tried everything' but can't get it running smoothy (or at all sometimes) and it's turned out to be fuel that is the problem. :-(
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Bob uk
Unregistered guest
Posted From: 94.197.122.84
Posted on Saturday, 15 November, 2014 - 09:36 am:   Edit PostDelete PostView Post/Check IP

I think UK petrol is different from other countries. Because my Honda lawn mower. I buy 20 litres in a jerry can which last the year. I have about 2 litres left from January and it's fine. But it is a Honda engine which is about the best available.

However if I had a cloud (I wish) that I had just brought as a non runner, any petrol I would drain and run my Jeep on it. Because it's a RR. And that SU pump can burn out the coil if the filters are full of clag.


The tank filter connected to the drain plug is fitted to many brit vehicles and I spent a stupid 4 hours trying to get a Austin J4 van to run properly when all that was wrong was that the tank filter was blocked with clag. ( Builders van so it's bound to have dirty fuel).

To clean dirty tanks remove and put nuts and bolts inside and shake.

But before take out the fuel float else it will get smashed up.

To remove all fumes and petrol. Fill tank with soapy water to the top and overflowing. Then empty.

To repair holes solder copper patch on. A hot air gun will just give enough heat to melt the solder, then using a small flame blowlamp run a bead of solder along the edges.

Use killed spirits or bakers fluid and solder paste and plumbers solder.

Cut copper pipe and bend it flat heat up to cherry red and quench in vinegar. This will clean and make the copper malleable so that it can be formed easily to the exact shape. Then tin both surfaces with solder paste. Sweat the patch with heat in place. Then run the bead and wipe while molten with a damp rag.

Quick wire brush up and thick coat of gloss black enamel or ICI chassis black which was invented especially for this sort of application. Brush it on.

Most brit stuff the screws for the sender are 2 BA. About 5mm dia.

Or radiator shops also do fuel tanks.

Other ways of flush are nitrogen argon and co2. Or maybe exhaust fumes.

(Message approved by david_gore)
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Ray Zeffert
Experienced User
Username: rayzef

Post Number: 12
Registered: 4-2006
Posted on Saturday, 15 November, 2014 - 08:53 pm:   Edit PostDelete PostView Post/Check IP

Mark
Thanks for the information on 95, 98 octane I use 98 and had about 15ltrs left in the tank for 10 months, I did not drain but filled with fresh 98 approx70 ltrs and some upper cylinder head lubricant,with new electronic fuel pump all is well but still lack power up hill.Will install electronic ignition in a couple of weeks and hope it cures poor starting and lack of power.
Thanks for the help
Ray Z

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