| Author | Message | ||
     Mark Tennison New User Username: fixstuff Post Number: 13 Registered: 11-2020 |
Corniche DHC 1978-1980 pierburg pump, Solex carb, fuel tank between rear bulkhead and Luggage area. Been trying to identify the problem that my car will stall after being parked across the slope of our drive after about 30 secs to a minute of running. However if parked on the flat/level it will run continuously until turned off. The fuel lines have been replaced and the in-tank filter cleaned, the tank internals cleaned as much as poss, new Crossland filter, Flow & Return & one way valves checked, as I was doing experiments after fitting a new fuel sender I know the tank has 19ltrs in it which for my car turns off the low fuel warning light. (FYI I also know that you need to put 1.380 Ltrs of fuel in the dry/empty tank before fuel starts to flow through the in-tank filter and down the flow/feed pipe to the pump). Could it be that even with 19 ltrs of fuel in the tank when parked at an angle the fuel is moving to the opposite side of the tank from the in-tank filter and starving the fuel system. !? or something else ? Note: All of the above work was not done to solve this specific problem, its just to set the scene. Main reason was to remove ethanol sensitive hoses, blocked hoses, o-ring.... and replace fuel sender..... Your thoughts much appreciated. | ||
| Omar M. Shams Grand Master Username: omar Post Number: 2112 Registered: 04-2009 |
Try doing the same parking position with the tank half full and then see what the outcome is. | ||
| Trevor Hodgekinson Frequent User Username: wm20 Post Number: 227 Registered: 11-2006 |
Most likely the low oil sensor shutting down the engine. I had a very steep drive when at Lindfield and had the same problem. To get the car into the garage I had to stop at the bottom of the drive walk up & open the door then drive strait in. If I stopped on the drive , the engine would shut down before I got back in. If there was a passenger so I was there with my foot on the brake it would continue to run. Finally we worked out if I reversed in then nothing happened. | ||
| Larry Kavanagh Frequent User Username: shadow_11 Post Number: 757 Registered: 05-2016 |
Low oil pressure sensor is in the wiring loop to the twin SU fuel pumps on my Silver Shadow 11, maybe yours has a similar wiring setup. Check your oil level. Idling on a steep slope might cause the engine oil to drift to the end of the sump away from the oil pump intake strainer. | ||
| Robert J. Sprauer Frequent User Username: wraithman Post Number: 672 Registered: 11-2017 |
This is not a low oil problem. The sump float sits in its own cavity and is constantly submerged, offering plenty of oil in any position. I would look at sticky floats. | ||
| Larry Kavanagh Frequent User Username: shadow_11 Post Number: 758 Registered: 05-2016 |
I'm talking about the 3 oil pressure switches that are screwed into the front of the oil filter housing. The larger one works the pressure gauge and one of the 2 smaller ones (possibly the lower one but my memory could be defective) is wired to the fuel pumps on my car. I have twin SU pumps but maybe the Pierberg pumps are wired the same, I'm not familiar with the Pierberg setup. | ||
| Mark Tennison New User Username: fixstuff Post Number: 14 Registered: 11-2020 |
Oil level, quality and pressure all excellent. Tried putting another 15 ltrs of fuel in addition to the 19 ltrs (gauge indicated just above first white empty Mark) already in the tank so about 34 ltrs in total (gauge showing 1/4 full) (Takes 113ltrs max). No more problem, so looks like that somewhere below 33 ltrs need to be mindful of lefthand side down tilt.! I guess easy answer is to keep at least 1/4 fuel in tank. | ||
| Omar M. Shams Grand Master Username: omar Post Number: 2113 Registered: 04-2009 |
success!!!!! | ||
| Mark Tennison New User Username: fixstuff Post Number: 19 Registered: 11-2020 |
We celebrate to soon... did it again, I need to start eliminating potential reasons, Facet pump to be fitted today, I also plan to put a monitoring LED on the Coil 12v and fuel pump 12v I'll try to position these so they can be viewed while driving, depending how these behave may give me a clue. It's been suggested sticking float/needle valve anybody any experience of this on a Solex 4A1 ? . Any other ideas much appreciated. | ||
| Mark Tennison New User Username: fixstuff Post Number: 20 Registered: 11-2020 |
I don't think it's car tilt/slope related as I deliberately drove up some of the steepest roads in the area no problem. The other thing which may be a clue once stalled it can be started again almost immediately and then drive perfectly for several miles. | ||
| Omar M. Shams Grand Master Username: omar Post Number: 2117 Registered: 04-2009 |
If the tilt is not the reason for your intermittent failure then it sounds like the same issue I am working on right now with a 1978 Wraith II. On that car the ballast resistor is breaking down. One minute it works and the next - one of the connections is open circuit. | ||
| Mark Tennison New User Username: fixstuff Post Number: 32 Registered: 11-2020 |
Think I have in tank filter/strainer probs as I T'd in an auxiliary 1 ltr fuel tank just before the pump, I had the car running and sure enough pressure at the Solex carb started to drop from 3.5 psi to <1 psi, I turned ON the flow of the Aux unrestricted tank and the pressure went strait back to 3.5 psi. Now draining tank to inspect strainer.... I would like to find the pump relay but its not where the workshop manual says it is i.e. its not in the boot RH side, its not by the steering column RHD ! ? | ||
| Hubert Kelly Frequent User Username: h_kelly Post Number: 417 Registered: 03-2012 |
https://www.google.com/search?q=rolls+royce+silver+shadow+petrol+filter&client=tablet-android-samsung&prmd=isvn&source=lnms&tbm=isch&sa=X&ved=2ahUKEwj26qertYPvAhVYVRUIHVNSDpQQ_AUoAXoECA8QAQ&biw=601&bih=962&dpr=1.33#imgrc=0a8gam9UtckqWM | ||
| David Gore Moderator Username: david_gore Post Number: 3891 Registered: 04-2003 |
Hubert, I presume this image is what you were trying to post:   | ||
| Hubert Kelly Frequent User Username: h_kelly Post Number: 418 Registered: 03-2012 |
That's the one David, thanks | ||
| Hubert Kelly Frequent User Username: h_kelly Post Number: 419 Registered: 03-2012 |
Larry, saw another RRSS1 today, gold colour, covered in dust, close to the old Burlington Hotel Dublin, the car was heading in the direction of the city . Real nice to see the old girl out and about, I'll keep an eye on donedeal in case it hits the market. | ||
| Mark Tennison New User Username: fixstuff Post Number: 34 Registered: 11-2020 |
Removed the In-Tank fuel filter/strainer and found it to be very restricted with ultra fine particles. As standard the Facet Red Top pump I fitted has a 74 micron pre filter and after the pump but before the Carb is the Crosland 444 filter at 25 micron ?, then the Solex carb has its own pre filter ?? micron, so I think there is adequate filtration external of the tank. Rather than discard the In-Tank filter I modified it so that it would strain out anything larger than ~2mm this should ensure the pickup pipe ~7mm ID never gets blocked by a random large particle. Its far easier to change or clean the Facet filter than emptying the fuel tank to remove the In-Tank filter to clean or replace (BTW NA) ! So now rock solid 3.2 psi fuel pressure at the Solex Carb i.e. no rapid fluctuations, no gradual reduction of pressure 3.2 to <1 psi after 10-15 mins of idling and so far no stalling. Thanks for all your input | ||
| Larry Kavanagh Frequent User Username: shadow_11 Post Number: 761 Registered: 05-2016 |
Hubert, your sighting of a Silver Shadow near the old Burlington begs 2 questions: (1), was it kerb crawling and (2), what were you doing looking at an old girl near the Burlington? You do realise that the locality has traditionally been considered a den of iniquity! | ||
| Hubert Kelly Frequent User Username: h_kelly Post Number: 420 Registered: 03-2012 |
Larry I'm a frequent visitor to the Burlington road, but not for the above reasons. I drive the 39/39a route pretty regularly . Bye the bye Larry did ya see the the 1980 RRSS 2 that sold on done deal within 24 hours it looked good value at 5,500 euro. Took my own car our yesterday for local trip to shops , she hasn't been out for months.. | ||
| Larry Kavanagh Frequent User Username: shadow_11 Post Number: 762 Registered: 05-2016 |
Hi Hubert, It's good to drive these cars as regularly as possible. You inspired me to take my SS11 out today, took her for a 30 mile run and she performed well but I noticed a slight misfire nearing home, must have a look at the plugs and ignition, I know that the carbs are set up well but it could also be down to stale fuel. I might have seen that SS11 on DoneDeal, was it dark Blue? I've quit looking at classic cars online as I'm addicted and already have 10, some are driving and others are in various stages of restoration or decay and I'm renting garage space but not making great progress as I have too many ongoing projects. My brother Ken retired from Dublin Bus recently, he was a driving instructor based at Clontarf garage, you might know him but maybe not since you're probably working out of Donnybrook. | ||
| Trevor Hodgekinson Frequent User Username: wm20 Post Number: 229 Registered: 11-2006 |
Filters are generally fitted to protect the item next in line which would be the fuel pump and in particular the diaphragm valves So be wary of low fuel pressure , keep an eye on it, you might need an in line filter before the pump to replace the in tank one you have modified. | ||
| Mark Tennison New User Username: fixstuff Post Number: 35 Registered: 11-2020 |
"the Facet Red Top pump I fitted has a 74 micron pre filter and after the pump but before the Carb is the Crosland 444 filter at 25 micron ?, then the Solex carb has its own pre filter ?? micron, so I think there is adequate filtration external of the tank." |
