JJC Posted December 15, 2014 Report Share Posted December 15, 2014 Anyone know if the flexible hose going to the MU is unleaded proof? Part No 214890. JJC Quote Link to post Share on other sites
flatlandsman Posted December 16, 2014 Report Share Posted December 16, 2014 Probably, but if you'e asking as your own hose has perhaps started to split then just maybe it's just old!! These cars were designed to have a life of around 15 years or so, and if your hose hasn't been replaced in a while, then it's reached the end of its service life. Quote Link to post Share on other sites
astontr6 Posted December 16, 2014 Report Share Posted December 16, 2014 HI! If you are still using the original hose(s) the answer is certainly not! What makes this dangerous is that the material disintegrates from the inside out often bits of rubber compound will stick the poppet valve(s) on the injectors. When the filter OE Lucas gauzes have been removed from the injectors on re-con injectors. There is also a problem with hoses that were replaced in the 1990's with the introduction of unleaded fuel. What was OK in the !990's for unleaded will not be OK for 2010 fuel onwards, as the formulae has changed, some what. The fuel on sale today is much more aggressive on those rubber compounds. At present I do not know what is the recommended spec. for rubber type hoses but I have noticed that Southern Carb. advertise low pressure fuel hose(s) that are resistant to todays fuels. The Goodyear Hose web site would be a good starter for the spec and hose type for high pressure! Some people are already using PTFE -S/S Braided Hose which will be resistant to modern fuels, as used in the Aerospace Industry. If you go down this route do not use smooth bore PTFE, only use convoluted type ( this is the flexible type, rated at 200psi max). This is because you may induce the dreaded harmonic fuel pump/release valve noise. Bruce. Quote Link to post Share on other sites
Nick Jones Posted December 16, 2014 Report Share Posted December 16, 2014 You want hose to SAE J30 R9 specification, which is resistant to petrol with ethanol, though the older R6 seems to do ok as well . Nick Quote Link to post Share on other sites
JJC Posted December 16, 2014 Author Report Share Posted December 16, 2014 You want hose to SAE J30 R9 specification, which is resistant to petrol with ethanol, though the older R6 seems to do ok as well . Nick Thanks - I now know what question to ask when I ring up to order a new one. JJC Quote Link to post Share on other sites
astontr6 Posted December 17, 2014 Report Share Posted December 17, 2014 Nick--------Thanks for the spec number! JJC-------- Upon checking that spec. I would only use the R9 type as it is the current spec for cars being manufactured today and is designed for 10% Ethanol. Also beware of old stock?? It might be better to go to your local hose assembler than going to a TR parts supplier. Bruce Quote Link to post Share on other sites
Stanpartmanpartwolf Posted December 17, 2014 Report Share Posted December 17, 2014 Excellent advice. A side issue that frequently arises: some female BSP unions on new hoses have seriously undersized bores, sometimes down to 4-5mm. ALWAYS check against your original hose before fitting, as the constriction can spoil fuel flow. A carefully wielded drill often helps. Quote Link to post Share on other sites
geoffd Posted December 17, 2014 Report Share Posted December 17, 2014 Some discussion here could be of interest http://www.locostbuilders.co.uk/forum/9/viewthread.php?tid=153126 Geoff Quote Link to post Share on other sites
JJC Posted December 17, 2014 Author Report Share Posted December 17, 2014 Well, and I thought it would be simple! Very informative posts, many thanks for all the posts. I wonder how many non Forumites know this sort of stuff? JJC Quote Link to post Share on other sites
Nick Jones Posted December 17, 2014 Report Share Posted December 17, 2014 Yep, that Locost thread is the one that educated me after issues with "fuel stink" when I EFI'd my PI. Fuel was permeating through the hoses (new, proper Gates branded injection hose but without SAE markings). Replacing it all with R9 hose cured the problem. I did take it up with my local motor factor who'd supplied the original hose, but they weren't very interested. Nick Quote Link to post Share on other sites
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