| Author | Message | ||
     Robert Gardner Experienced User Username: bobg Post Number: 20 Registered: 12-2012 |
How much effect would it have on the car if it is operating on a generic single fuel pump and not the original dual pumps designed for the car ? Car is a 72 Shadow | ||
| Brian Vogel Grand Master Username: guyslp Post Number: 994 Registered: 6-2009 |
Many do, even with the dual pumps, if one side has failed but the other is still chugging along. That was the case for SRH33576 and I've had many others tell me that they had similar situations when it came time to tear down the pump for a rebuild. The two most common alternatives I know of people using are a Facet Red Top fuel pump or Airtex 8016 pump with a 3.5 PSI pressure regulator (this arrangement also works for Cloud/S era cars). After all, US delivery (and several other markets as well) went to the Pierburg rotary vane single pump while home market (and, again, several other markets as well) cars stayed with the dual SU on the Shadow II/T2. When working on LRK37110 I took the opportunity to add a stop valve in the fuel line just outside the US spec fuel tank so that I could cut off fuel for any "forward of the tank" work in the future. The arrangement of the European spec tank on SRH33576 didn't make this change necessary. I've never dealt with an original series Shadow with US delivery in this arena, so I don't know whether this even applies, but it doesn't hurt to consider it. Brian | ||
| Brian Vogel Grand Master Username: guyslp Post Number: 995 Registered: 6-2009 |
It also appears that there are several Facet Gold-Flo models that meet the workshop manual specs for our cars without the need for a pressure regulator. The Airtex E8016S has a 2.5 to 4.5 PSI pump output range, 30 GPH free flow output, so it's a good fit from the required pressure/volume perspective, too. Brian | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 3054 Registered: 4-2003 |
Better still, relocate the fuel tank to the roof and rely on gravity feed. Then again, why bother with all this fuss in the first place when the correct fuel pumps are easily bought brand new ? | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 894 Registered: 9-2004 |
Why not use them at all. Just run the car on LPG better for the engine and the environment. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 3055 Registered: 4-2003 |
Better still CNG, as methane has the CO2 advantage over LPG and petroleum. As fuel taxes head towards CO2 output, LPG will become more expensive per mile than petrol, and CNG (methane) will cost half. | ||
| Brian Vogel Grand Master Username: guyslp Post Number: 996 Registered: 6-2009 |
1. The SU fuel pump is far more prone to vapor lock if you drive in either a very warm or high altitude environment. 2. Either of these pumps can be installed as a backup pump upstream of an SU and can pump fuel through it if it suffers vapor lock. It goes without saying that power is switched off to the SU if this is being done. 3. A replacement SU AZX 1405 pump costs approximately $295 US at Empire British Car & $275 US (sans shipping and VAT) at Burlen. 4. Two replacement EPK 300 pump rebuild kits currently go for $102 USD (sans shipping and VAT, and don't forget to switch out the supplied varistors for diodes). 5. A new Airtex ES8016S is just under $30, while the Facet Gold Flo 476087E is about $80 and installation of either is simple (and reversible, should anyone desire). Either works perfectly. 6. Pierburg rotary vane pumps, which were OEM, are no longer obtainable and must be replaced upon occasion. [The original questioner lives in the United States, so LPG is a non-starter as far as any reasonable ease of availability goes.] | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 3056 Registered: 4-2003 |
Yet again anything but the right part goes it seems, especially to save a few small dollars. The next owners of these cars may elect to go to a specialist for maintenance only to be turned away because of the plethora of alterations. The specialists I know let out very interesting arrays of four-letter expletives as a minimum when a bodgie drives in for work. By the way, brand new SU pumps are available locally in Sydney and at very reasonable prices. Not that they are at all troublesome even after 35-70 years. | ||
| Brian Vogel Grand Master Username: guyslp Post Number: 997 Registered: 6-2009 |
If a part performs its function, perfectly and without issue, it is "the right part" whether it came from the factory or not. Using them is not a bodge in any meaningful sense of that word. Any professional who uses 4-letter expletives over the use of fully functional and simple to replace aftermarket parts is not one I, or many others, would call a professional. The original questioner clearly has an SU fuel pump that is either in a condition that would not permit rebuilding or simply does not want to do so. He asked a legitimate question and it has a legitimate answer. Getting all pissy because he wishes to go a route you would not choose yourself helps no one. This is your personal bugaboo. Would that you'd just let go of it and allow others who don't share it to have civil and informative conversations. It will probably be a cold day in hell before that happens. Brian | ||
| Chris Miller Prolific User Username: cjm51213 Post Number: 218 Registered: 5-2013 |
Hi Richard, > SU pumps are available locally in Sydney and at very reasonable prices Not if you include the airfare from the U.S. necessary to fetch them. The cost of an item includes everything necessary to deploy it, which usually includes getting it to where it can be used... Chris. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 3058 Registered: 4-2003 |
Ah, Chris, but we are in Australia. Have it your own way. I must point out that people are invariable citing substitute spare parts. Aftermarket parts are something completely different being legitimate replica components as opposed to substitutes which may do the job sometimes. I do note a 4-letter expletive in the post last but one, albeit with a y added. | ||
| Chris Miller Prolific User Username: cjm51213 Post Number: 219 Registered: 5-2013 |
Hi Richard, > Ah, ... but we are in Australia. as all the best people are. But the original poster who is trying to resolve a real problem is not, so prices in Sidney are less helpful, unless you're offering to become an agent for Sidney exporting, which might be a beneficial service, and possibly a good business opportunity for you. You should quote a price for that part delivered. Maybe the original poster will buy it from you. Most "expletives" are not bad words; they are old words dating from pre-Norman (pre-1066) Anglo-Saxon inhabitants of England, which after the Norman invasion in 1066, were subsequently disparaged for their lack of fluency in French. These words became a "reverse shibboleth" for the non-Norman under-class, and the prejudice inflicted on their users is why they carry the superstition "bad" today. So the "expletives" are generally far and away the more authentic English vernacular. But I am guilty of "thread drift", and "vocabulary" is not a topic that I should responsibly introduce into a thread which is clearly not discussing linguistics, or cultural assimilation and migration. NB: not discussing vocabulary. Chris. | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 1246 Registered: 6-2006 |
Robert as a professional I would recommend staying with the original ones for quite a few reasons. longevity and being able to maintain them if you wish or need. (Please don't start screaming about rally and race cars use them so they must be great. They get swapped out like everything else on race cars so longevity and noise levels are not an issue.) Most replacement pumps sound like you've left a vibrator or electric razor running under your seat. Not pleasant at all. Also for vehicle resale value. Whenever a purchaser starts looking at a car and they start to spot things been swapped out for any reason it will plant the seeds of doubt about a cars maintainence and repair program and this can knock thousands of pounds off the value of a car. Original tried and tested parts are available. A bit more expensive in the short run but better and cheaper in the long run. If you mean can you use a single SU pump. Yes - but not recommended. IF you do decide to go down the cheaper type pump route, the engine will run the same. (Which I guess is what you may have been asking.) As an aside, I think you will find that Pierburg pumps were fitted to vehicles with a recirculatory fuel system not because of where they were destined for. And another: in the past driving a car that needed continual maintenance every journey and were a death trap and s**ting in the street was also not considered 'bad'. I think most reasonable people would accept that doesn't mean it's ok today though :/ | ||
| Brian Vogel Grand Master Username: guyslp Post Number: 998 Registered: 6-2009 |
I will simply note, again, that I answered the exact question posed by Mr. Gardner who is not unknown either to me or several other regulars here. He has owned the car in question for several years and is familiar with what is "correct." I, too, am familiar with what is "correct" and can and have answered questions about that when they are posed. When I see the phrase "generic single fuel pump" that rules out SUs as part of the answer. I know of individuals who have both of the pumps I've mentioned running on Rolls-Royce motorcars and that are doing so without issue. I have also asked about excessive noise and both report that they notice nothing out of the ordinary (except the missing "ticks" of the SU when it's quiet enough to hear it priming the carbs). It is not my place to enforce my vision of correctness on anyone. There is a difference between "correct" and functionally fully satisfactory or identical. People who are asking about alternatives know precisely what they're asking about and why. Defining aftermarket parts as only replicas of the originals is idiosyncratic, particularly when the part in question is something like a pump. Many aftermarket parts from major players in that market segment are not always visually identical, sometimes not even similar, to an original but can be fitted to perform their function with kits specific to the intended application. With Rolls-Royce and Bentley motorcars most aftermarket parts are not visually similar and are acknowledged as alternatives/substitutes. That doesn't make them substandard or "a bodge" (though, obviously, some can be so). Taking into account where a given questioner may be located when formulating an answer should be thought of as common courtesy. I participate on other forums where people from many countries post. I try to tailor my answer to their specific circumstances as much as my knowledge of those allows. With regard to the Pierburg pump. TSD4210 (the Silver Wraith II Owner's Handbook) states the following with regard to fuel pump: Cars destined for countries other than Canada, Japan, and the U.S.A. - Twin SU Electric Cars destined for Canada, Japan, and the U.S.A - Single Pierburg rotary vane electric, check valve mounted forward of pump I realize that the Pierburg system recirculates and the SU does not as I've got cars with one of each. Brian | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 3059 Registered: 4-2003 |
SU pumps are fairly generic in the UK and Australia for a start. Your SRH33576, neither of European nor US specification, surely has or has had one being an English-delivered car even if converted to left hand drive. Sure, these cars certainly drive very well with half the fuel pump U/S, flat tyres and no hubcaps, but it begs the question why. | ||
| Brian Vogel Grand Master Username: guyslp Post Number: 999 Registered: 6-2009 |
Yes, as I clearly stated I've got cars with each pump style. SRH33576, which started out life as pure European spec with a UK delivery has a dual SU pump. LRK37110, which was a U.S. delivery car right here in Virginia has a Pierburg. I have rebuilt the dual SU on SRH33576, and posted extensively on the RROC-US forums on same. SUs are far from generic in the U.S. as far as either parts or full replacements go. The fact that the cars can drive very well with one of the two dual pumps completely non-functional pretty much proves that they do not need anywhere near to the maximum output capacity of the dual setup. It is nice to have a backup, but far from essential. I doubt that most owners, or their mechanics, are religiously listening to both halves of a dual SU pump on a routine basis to know whether one half has died. If they were, there wouldn't be the myriad stories of only one having been working, probably for years if not decades, that are out there. A single fuel pump appears to be adequate for most of the motor vehicles traversing the planet, and can also be so for a Rolls-Royce or Bentley. No one's mentioned flat tyres, lack of hubcaps, or other things utterly unrelated except you. Why you choose to throw these non sequiturs out on a regular basis is known only to you. They certainly have nothing whatsoever to do with the question asked nor any fruitful discussion. They appear to be attempts to cast aspersions, and fail miserably. Brian | ||
| David Hughes Experienced User Username: wedcar Post Number: 44 Registered: 7-2004 |
The original question was - how much effect would it have on the car? Simple answer is, if the output pressure and flow are the same as the original it should have no effect on the cars performance at all. However, by using non standard parts for any car, time and usually money is spent "making it fit". In my experience using correct parts saves time and gives correct performance. Regards David | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 3061 Registered: 4-2003 |
Pardon me, but SRH33576 is not of any European-specification. It is of English specification. There is quite a difference. | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 1247 Registered: 6-2006 |
I'm not sure why you are having a rant but it appears to be directed at me. I am not sure why you feel the need to note that you have answered the exact question posed. Not sure if you are telling somebody else or yourself. Hope you weren't telling me because if you were you shouldn't flatter yourself so much. TBH I'm not interested in your replies. I am on here because I'm interested in answering Robert's question. Firstly, although you cunningly point out that you "have answered Roberts exact question", it does not mean mean that you have answered it fully. If it is not answered fully, it can not be considered to be answered Correctly. Just because you don't like my opinion or others opinions you should not take it so personally. You make your own decisions and let Robert make his own. But let everybody make educated decisions. I recommend that at each annual service you check that both sides are working. Disconnect one side and test the other, then swap the 12v feed over and check the other side. You will instantly know if it is just running on one side. No need to remove and rebuild the pumps to find out. Why bother? Because even if one side fails the next day, you have a fighting chance of making it to the next service before the other side fails. So much easier and cheaper than breaking down. | ||
| Bob uk Unregistered guest Posted From: 94.197.122.91 |
Mr Treacy! One would have to weld a roof rack to the car otherwise the tank will fall off the roof. Which is definitely a mot failure. Forgot Facet pumps have a poor reputation amongst the hot rod guys for bad quality control. I asked a hot rod guy yesterday while dribbling over exotic hot rod parts. (Message approved by david_gore) | ||
| Bob uk Unregistered guest Posted From: 94.197.122.88 |
I have to go with Paul Yorke on this one. I said that facet at £38 was a no brainer, that pump doesn't fit and a £100 one is needed. I have had a good look at the facet pump and they look not as good as a SU double pumper. SU pumps last 100k miles and 15 years so properly overhauled the SU is not unreliable. My car is 99.9% "bog standard" it even has English air in the tyres. The only bits changed from std are the radio. RR parts aren't that expensive when checking out other makes. A wheel cylinder for my Cherokee cost £54 and a No plate lamp assembly £26. £26 for badly made sh**y plastic rubbish. When I first got my car I disliked various mechanical aspects, but after 25 years I have come to understand why RR designed the car so, and modifications such as facet pumps Will devalue the car. Things like kunifer brake pipes, braided hoses and stainless exhaust are OK and expected but to me a facet pump changes the flavour of the car. (Message approved by david_gore) | ||
| Brian Vogel Grand Master Username: guyslp Post Number: 1000 Registered: 6-2009 |
Paul, It is utterly rich for me to be lectured, by anyone, to "make your own decisions and let . . . make his or her own." Would that this were a universal philosophy. It seems to be indulged less and less in these parts. Condescending pronouncements about correctness, rather than functional fitness, are intended to shut down independent decision making based upon all options and information offered. I never claimed to have answered any query fully. As was so accurately observed by Robert Heppe: A sensible person realizes that all principles that can be expressed in a statement of finite length are oversimplified. Of all the things I can be accused of, lack of thoroughness is very seldom one of them. Brian | ||
| Bob Reynolds Prolific User Username: bobreynolds Post Number: 148 Registered: 8-2012 |
I bet the OP wishes he'd never asked now.  | ||
| Jan Forrest Grand Master Username: got_one Post Number: 633 Registered: 1-2008 |
The real question should be "What would Royce do (fit) if he were alive today? The answer is simple: The best available proven technology regardless of source! | ||
| Bob Reynolds Prolific User Username: bobreynolds Post Number: 149 Registered: 8-2012 |
I think Crewe had already abandoned that philosophy by the time of the Shadow! | ||
| Robert Gardner Experienced User Username: bobg Post Number: 21 Registered: 12-2012 |
My My, Just look what I've started! This thread would never have taken on a life of its own had I worded my question a bit more clearly. When I purchased the car, it had the single pump on it already, which I did not even realize until late last year. Anyway, I did however purchase an SU Pump shortly thereafter, but have just not gotten around to installing it. So I guess my initial question is just "is it ok for that thing to be on there ?" I know now that it is, but installing the new pump would be far more beneficial in the long run. Thank you all for your useful information. Now, off to contemplate what my next question should be. | ||
| Mark Aldridge Prolific User Username: mark_aldridge Post Number: 148 Registered: 10-2008 |
At the risk of stirring a hornets nest, I see that Facets are sold as replacements for the obsolete Pierburg pumps by the UK specialists. Are these OK with a recirculating system or would something like a Holley vane pump be better ? Mark | ||
| Brian Vogel Grand Master Username: guyslp Post Number: 1012 Registered: 6-2009 |
Mark, David Hughes put it most directly in the middle of this thread: "Simple answer is, if the output pressure and flow are the same as the original it should have no effect on the cars performance at all." There are many cars on which recirculating fuel systems were used (I'd venture to say most, in fact, since the advent of fuel injection). Fuel pumps have no problem "chugging right along" rather than operating "stop and go." It would be interesting to know if the Holley vane pump would "sound more like the Pierburg did" if its output pressure is no more than 5 PSI (or thereabouts). Rotary vane pumps are supposed to be quieter than diaphragm types, but I don't hear that on my cars. There's a distinct difference in the sounds, the ticking of the dual SU versus the hum-whir of the Pierburg, but I wouldn't say the Pierburg is quieter. Carter and Mallory also make rotary vane type fuel pumps. If you're replacing a Pierburg do post again regarding what you've gone with and what was required to fit it. Brian | ||
| Bob uk Unregistered guest Posted From: 94.197.122.88 |
Recirculated petrol systems do have the edge on pressure regulation. The amount of extract power require is small. And it stops vapour locks. My car is lpg which needs no pump. I never noticed my SU ticking when I used to run on mucky petrol inferior smelly exhaust liquid fuel that washes oil off during cold starts, mind you what with the radio and wife and daughter I can't hear any mechanical noise. (Message approved by david_gore) | ||
| Brian Vogel Grand Master Username: guyslp Post Number: 1014 Registered: 6-2009 |
Bob, I can't hear either the dual SU pump or the Pierburg pump at any time during "typical driving conditions," including being at a stop. The only time I can hear them is in the garage or driveway when I'm about to start the car and the engine is not yet running. This is sans radio or familial background conversation. Brian | ||
| Bob uk Unregistered guest Posted From: 94.197.122.81 |
When my daughter was very young I was driving a Rover P6 3500S and I could hear a strange sucking noise which sounded like a vacuum leak. It was her sucking a bottle. When the wife and daughter get going they run out of full stops and commas. Then they start phoning friends. I've got use to it. Maybe the pump could be fitted by the rear fuel filter. (Message approved by david_gore) |
