John Bracher Posted July 31, 2015 Report Share Posted July 31, 2015 Hi Gents. I have now been using my 1974 CR for @1 year, but this is my first post (as opposed to 'The Last Post), such Irony!!! I had the (apparently mandatory) 'petrol smelly' boot, a while back, and so decided to attack it! No signs of leaks, checked all fittings,monitored with Talcum powder, A4 inkjet paper, but no witness marks! Still smelly, so changed all the hoses/rubberwork, and removed and cleaned the tank (inside and out). Also replaced the Bosch filter (unknown age). The hose from the Pump to the PRV (original PRV) was a cotton braid covered one, approx 12" long (unknown age). Maybe this was 'sweating'??? As the hose supplier I used was limited on hose types/stock, I ended up with a PTFE lined, stainless braided of 24" length. The result is, while the car runs fine, and NO SMELL. BUT it sounds like a Bugler is signalling from my boot when the pump is running!! By moving/wiggling the braided hose around, I can (almost) play a tune! I believe this to be 'the known resonance issue', as it goes away if I put the old hose back on. Q. Has anyone tried using same/different length of plain '7.9mm SAE J30 R9 cordan fuel hose' (or similar) or 'Bio Proof' fuel hose to dispel the noise, or do I really need a Diaphragm type PRV??? Obviously, the hose (£15) would be my preferred option, but would like to avoid that 'in addition' to an eventual £120 for a new PRV!! Your advice is appreciated! JB Quote Link to post Share on other sites
Prefect Posted July 31, 2015 Report Share Posted July 31, 2015 I bought the RTR Diaphram PRV never a C sharp since still a faint whiff though???? Quote Link to post Share on other sites
snowric Posted July 31, 2015 Report Share Posted July 31, 2015 or from malcolm at prestige injection. Both work. Quote Link to post Share on other sites
Andrew Smith Posted August 1, 2015 Report Share Posted August 1, 2015 Given this only started when you changed the hose I would suggest the PRV is ok, so speak to Revingtons and ask for a shorter rubber PTFE lined hose before throwing money into a diagphram PRV. Cheers Andrew Quote Link to post Share on other sites
Lockley210 Posted August 1, 2015 Report Share Posted August 1, 2015 Had the same issue with the orchestra in the boot and cured it by fitting a 2m long hose from pump to prv. Cheers Mark Quote Link to post Share on other sites
John Bracher Posted August 1, 2015 Author Report Share Posted August 1, 2015 Thanks for the speedy responses! I will have a go with some 'longer/shorter' hose, with temporary ends, before getting them properly crimped (if successful!) While I am 'in there' I am tempted to strip and clean out the PRV? Anybody had any severe FUBARs doing this? Do the pressure settings escape during dismantling? (I have no pressure gauge, so can't rectify, if this is the case) An additional observation, while driving with the hose 'blaring' I was aware of a 'buzzing' noise from around the metering unit/bulkhead/under dash area, which I presume to be the copper fuel lines ('alto' section of the orchestra)? Lastly, (and this may be imaginary), although I only drove the car about 8 miles, the fuel gauge appeared to drop more than usual? This, however, may just be me forgetting the 'cost of ownership'.......! Any suggestions/thoughts?? Quote Link to post Share on other sites
astontr6 Posted August 1, 2015 Report Share Posted August 1, 2015 Dear John, The rubber hose used in the UK is usually the R7 type of the SAE spec.J30 which in the US has been superseded by the R9 over 5+ years ago! The petrol smells that people experience is caused by permeation through the wall of the hose. The R9 hose meets the very low permeation allowed in the SAE spec, its about 3000% less than the R7! This requirement meets the standards of many US States. Gates in the US are one of the market leaders for this product called Barricade but its seems to be unobtainable here in the UK through their distributors for their injection hose type,It can be used with 100% Methanol and Ethanol fuels. I tried to obtain Codan 3/8" hose but have been unable even after speaking to their Rep. If you know where let me know? I now am waiting for a friend of mine to send me some 3/8" Gates from Canada. Regarding PTFE Hoses, the ones that I saw for sale at the IWE etc. are for 1000 psi + rating, which in my view are totally the wrong type of spec. I would not use smooth bore hose but use convoluted PTFE hose rated at 150 psi which would have some flex in it etc. The noise that people hear is caused by the pulsing of the Bosch pump on the Lucas PRV, which produces this harmonic noise. Bruce. Quote Link to post Share on other sites
John Bracher Posted August 1, 2015 Author Report Share Posted August 1, 2015 Hi Bruce. Sounds like we (collectively) are both 'grazing our foreheads' on the Cordan brickwall! I have ordered some SAE J30 R9 hose from these guys http://www.advancedfluidsolutions.co.uk, to do some short term testing in the meantime. I too, had little/no joy in finding 'known genuine' Codan hoses here, so have contacted the Danish parent company. I know some folks in Denmark, so may contact them, if no joy from Codan. By all accounts EBay is littered with counterfeit product, so am avoiding that route! What fun!! Quote Link to post Share on other sites
astontr6 Posted August 1, 2015 Report Share Posted August 1, 2015 Hi John!, I spoke to AFS and I was unhappy that their product is unbranded and is also supplied without a C. of C. Therefore I did not order any of their product! Regards, Bruce. Quote Link to post Share on other sites
John Bracher Posted August 2, 2015 Author Report Share Posted August 2, 2015 Hi Bruce. Agreed, but my intention is only to use this as a 'test' I want known product for the final fit. I have ordered 2m and will reduce the length (possibly until it is short enough to go into the bin!) Q. Have you ever stripped a PRV? Good/bad/useless waste of time? I am looking for something to do til my goods arrive (and don't want to mow the grass!) BTW, I have had a response back from Cordan UK, asking me how much 7.9mm ID 3133 hose I want to buy? I will post their answer if it is sensible/viable. JB Quote Link to post Share on other sites
astontr6 Posted August 2, 2015 Report Share Posted August 2, 2015 Hi John, Yes I have but I have never had any problems with mine, it is the original one! Years ago on another car a 2.5 PI Saloon, we stripped one down because it was playing up (low pressure) and found a piece of crud causing the problem. Therefore in my view if you have good pressure at the M/U, I would leave it alone. I have also been taking to some of the racing boys at Silverstone, last week, about fuel hose, hoping that they were using R9 but they still seem to be using R7! Re: The harmonic noise. In my experience the more soft and flexible the hose the less lightly do you get the noise. In had to change my last hose because it became very hard with age/using unleaded fuel and I start to get the noise. Then I changed to a new soft hose R7 rated at 150psi no more noise. Bruce, Quote Link to post Share on other sites
John Bracher Posted August 2, 2015 Author Report Share Posted August 2, 2015 Well, to avoid 'other duty' I decided to strip down the PRV. What a hoot! Access is not what it could be, next time I take the tank out of a TR, I will refurbish the entire car!! Anyway, PRV out, cleaned (strainer had apparently been doing it's job), and re-assembled. Refitted, and began playing 'musical hoses' (quite literally!!) In a 'strapped up figure of eight' position, fired up and ran engine for 5 minutes, all I can hear is the fizzing of the pump!! Joy!!! Quick check for leaks. End of joy! Slightly leaking PRV to union joint!!! Only slight, but I suppose the resulting explosion would also only be 'slightly' devastating! So, PRV once again currently stripped down, needing replacement washers.... (as per brown book) -- note to self, RTFM next time..... Hey ho! Beer time....... Quote Link to post Share on other sites
astontr6 Posted August 2, 2015 Report Share Posted August 2, 2015 John, Glad you have sorted it out and are happy! Bruce. Quote Link to post Share on other sites
mike3739 Posted August 2, 2015 Report Share Posted August 2, 2015 Well done, beats doing the other job Cheers Mike Quote Link to post Share on other sites
John Bracher Posted August 5, 2015 Author Report Share Posted August 5, 2015 Gents, an update. I have obtained some genuine Codan hose SAE30 R9 7.9mm. It works, and all I can hear while the pump is running, is the 'zizzzzzzz' of the pump. Engine running, no change, 'zizzzzzzz' and thrummmm/puff puff (twin exhausts). Have tried 18" up to 2 m, no resonance.buglers! length appears irrelevant, (you see, it is true! ) My only issue now, is that I cannot get a good 'bite' between the hose and the tails?? I can do the hose clips (proper size and type) up until they bottom out. The hose then still turns on the tail, fortunately, with no leaks, even between the pump and PRV! I am not comfortable though, with the lack of 'physical security'. I believe this 'issue' is due to the internal coating on the R9 hose, as I can lock an R6 hose 'tight'. Does anybody have any ideas, do you think crimped ends would be better? I am trying to get some smaller bore hose, but am concerned over fuel volume if too small?? Has anyone used replacement/larger/different tails and fuel tank connections? Hmm, just want to put the boot floor back in and drive........ Quote Link to post Share on other sites
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