stevenphillips Posted March 27, 2021 Report Share Posted March 27, 2021 (edited) Evening all Did a search on this but nothing i can find, anyway, took the 6 out yesterday ran like a dream. Took it out again today and for some unknown reason it was running like a tractor. Anyway checked ignition etc and finally found this evening that injectors 1 & 2 are just kind of almost dribbling where as 3 4 5 6 have a nice fine cone. It's almost like 1 & 2 have no fuel being sent to them. Anyone seen this or can point me to the correct thread so that I can look in the right place as opposed to looking everywhere and possibly finding other work to do lol Thanks as always Steve Edited April 15, 2021 by stevenphillips Update to thread Quote Link to post Share on other sites
kcsun Posted March 28, 2021 Report Share Posted March 28, 2021 Try swopping a good injector with a bad one. It will then prove if its the injector or the supply kc Quote Link to post Share on other sites
Paul Hill Posted March 28, 2021 Report Share Posted March 28, 2021 Have you blew some compressed air through the injectors so to eliminate that cause. On a couple of occasions I have had **** in the injectors. Quote Link to post Share on other sites
stevenphillips Posted March 28, 2021 Author Report Share Posted March 28, 2021 Ok thanks I will give that a go Quote Link to post Share on other sites
astontr6 Posted March 28, 2021 Report Share Posted March 28, 2021 42 minutes ago, Paul Hill said: Have you blew some compressed air through the injectors so to eliminate that cause. On a couple of occasions I have had **** in the injectors. or bits of rubber from the breaking up of the 'O' ring. Do as above then bleed them to purge the air out to see if that cures the problem. I made up an adaptor years ago to screw on to the injector and then connect to a high pressure cycle pump (150psi). It can blow out any Sh...!. no problem but also gives an indication as to how good the sealing is for that injector. When you look at the pressure gauge and monitor the pressure drop. Bruce. Quote Link to post Share on other sites
Peter Cobbold Posted March 28, 2021 Report Share Posted March 28, 2021 Probably vapour in hoses. Hold the injector up so that hose is vertical and get someone to rev up/down/up.. to give a bit of load and fuelling. Quote Link to post Share on other sites
Paul Hill Posted March 28, 2021 Report Share Posted March 28, 2021 I did exactly what you did Bruce I connect the Injector to my Stirrup pump clears them no problem, since I changed to a new fuel tank I have no further trouble. Touch wood Quote Link to post Share on other sites
stevenphillips Posted March 28, 2021 Author Report Share Posted March 28, 2021 Thank you Bruce I will see if I can make an adaptor and give that a go. In looking at the injectors tonight I found that my adaptors are the same as the screw in injector type but without any thread cut into the plastic ( my injectors are push type) has anyone got the same as these. I've looked online for a replacement as no6 adaptor is different and is a two slot push on type and I believe they should all be the same but I can't find adaptors the same as mine for now's 1-5 without a thread, any ideas ? Also no 4 adaptor is no coming out is there a tool that will enable this one to be pulled out. I will be ordering new o rings for the adaptors as mine are all flat Thanks Steve Quote Link to post Share on other sites
DaveN Posted March 31, 2021 Report Share Posted March 31, 2021 A 3/8 drill wound in by hand just to dig into the nylon then a sharp tug will pull it out. As for the injectors with the engine running, one at a time pull them out and give them a sharp whack with a hammer or the edge of a big spanner on the side, will sometimes get them to cheer up! Two types of injector fittings wise. Push fit and screw in. So there is two types of nylon holder, plain and threaded. Quote Link to post Share on other sites
JohnC Posted April 2, 2021 Report Share Posted April 2, 2021 On 3/29/2021 at 9:15 AM, stevenphillips said: Thank you Bruce I will see if I can make an adaptor and give that a go. No real need for an adapter if you have a compressor (and they are seriously cheap these days, and so useful). Just apply an airgun to the orifice. You'll get enough of a seal to do the job. On 3/29/2021 at 9:15 AM, stevenphillips said: I will be ordering new o rings for the adaptors as mine are all flat Unless your injectors have been reconditioned recently, it's worth replacing the internal 'O' ring as well. That may be the cause of your original problem anyway... Quote Link to post Share on other sites
CP26309 Posted April 2, 2021 Report Share Posted April 2, 2021 After more than 40 years with a CP Pi I changed all mine to push in type and carry a glove box full of new Injectors, when they play up I just pull over and chuck in a new one! Same goes for spark plugs...foul one, bung it away! I carry a box of new ones all the time. Quote Link to post Share on other sites
astontr6 Posted April 3, 2021 Report Share Posted April 3, 2021 On 4/2/2021 at 10:30 AM, JohnC said: No real need for an adapter if you have a compressor (and they are seriously cheap these days, and so useful). Just apply an airgun to the orifice. You'll get enough of a seal to do the job. Unless your injectors have been reconditioned recently, it's worth replacing the internal 'O' ring as well. That may be the cause of your original problem anyway... Your statement above is very true in para 2! That is why I use the adaptor with a high pressure cycle pump as they usually have a pressure gauge attached. This can be used to monitor the pressure drop. Any injectors that loose pressure quickly or do not hold pressure at all can be isolated to have their 'O' rings replaced. Saves a lot of money on re-con ones? I have had problems in the past with brand new re-con ones! They go straight back to the supplier and over the last 30 years I have sent back at least 10 off?? I have never had any back saying that there was nothing wrong?? Bruce. Quote Link to post Share on other sites
Phil Read Posted April 5, 2021 Report Share Posted April 5, 2021 I had this problem. Car ran ok most of the time and then for no reason would misfire, particulaly at low speed. I foung that no2 and 4 injectors were dribbling at low revs, under 2000. I was told by a club member it was probably the valves in the metering unit that were sticking and was told to give it the "Italian Spanner". This solved the problem, so whenever it re-occurs, which is seldom now I do the same. Find a long steep hill and go up it in the highest gear at full throttle (throttle open) engine under as much load as possible. Evidentaly it clears out any debris in the metering unit. It worked for me. Quote Link to post Share on other sites
stevenphillips Posted April 5, 2021 Author Report Share Posted April 5, 2021 Ok thank you all for the replies, really interesting. Couple of points to my earlier posts that may have been missed I think. I know there are two types of injector adaptors (1 push type with two groves and one screw type with one grove for the o ring) but mine don't look like either I have 5 adaptors that look like the screw in type (1 grove for o ring) but they do not have a thread and accept my push in type injectors and 1 adaptor that IS a push in type with two grooves. I would like to make them all the same as the 5 I have but cannot find this type on line, any ideas?? Moss and grimmer do not show this type. Is there a supplier that supplies good injector o rings together with adaptor o rings. I would like to replace them all asap Finally I've looked in the manual regarding replacement of the NRV for the MU but is there any tricks to this and who can supply Thanks for all your help and advice Steve Quote Link to post Share on other sites
stevenphillips Posted April 15, 2021 Author Report Share Posted April 15, 2021 Ok in an attempt to hopefully get an answer I have attached some photos to help. My issue is that the adaptors I have I cannot find anywhere. Mine are the same as the threaded type but without a thread. Anyone know why and where I can get a replacement. Also I have 4 injectors that are prefixed with E and 2 injectors prefixed with D. Does anyone know the difference and if it's better to keep them all the same or is mixing not an issue. Final question what is the reason for the nipple on the end of the poppet cone that makes the spray and is there any difference in spray pattern if it's missing, can see why it should affect it I suspect it could be a cooling device. Any answers greatly received as always Thanks Y'all Quote Link to post Share on other sites
aardvark Posted April 16, 2021 Report Share Posted April 16, 2021 Steve. Have you spoken to one of the PI specialists such as KMI, TR Trader or Neil Fergusson? All of them should be able to supply you quality parts. my 6 hadn’t been used for a long time when I bought it and had similar running issues as you. A series of refurb injectors cured for a short time only. I bought a new set of injectors from kmi and that totally did the trick. I had the metering unit calibrated and the seals changed by Neil too. Sometimes you need to bite the bullet and hit the problem as a whole rather than incrementally tickle the problem around the edges. the numbering on the injector is a part number and date and there is a suffix letter too. Earlier injectors will have an earlier suffix letter. Most injectors have the ‘projecting rod’ but the early ones don’t have it. They should all perform the same although logic would suggest the type with the projecting rod superseded the type without for some reason. the best advice concerning the PI is to use the car regularly and give it an Italian tune up whenever you do use it. cheers dave Quote Link to post Share on other sites
marting Posted April 18, 2021 Report Share Posted April 18, 2021 Hi Steven I have just had a rummage through my box of old injector collars. I have some of the design that are the same as yours. If you PM your address to me I will send you one out. Martin (Fred Millturn Parts) Quote Link to post Share on other sites
astontr6 Posted April 18, 2021 Report Share Posted April 18, 2021 On 4/16/2021 at 6:33 AM, aardvark said: Steve. Have you spoken to one of the PI specialists such as KMI, TR Trader or Neil Fergusson? All of them should be able to supply you quality parts. my 6 hadn’t been used for a long time when I bought it and had similar running issues as you. A series of refurb injectors cured for a short time only. I bought a new set of injectors from kmi and that totally did the trick. I had the metering unit calibrated and the seals changed by Neil too. Sometimes you need to bite the bullet and hit the problem as a whole rather than incrementally tickle the problem around the edges. the numbering on the injector is a part number and date and there is a suffix letter too. Earlier injectors will have an earlier suffix letter. Most injectors have the ‘projecting rod’ but the early ones don’t have it. They should all perform the same although logic would suggest the type with the projecting rod superseded the type without for some reason. the best advice concerning the PI is to use the car regularly and give it an Italian tune up whenever you do use it. cheers dave In the past some re-conners would not accept back injectors that did not have the pointed rod. There was a phase when Lucas removed the pointed rod before assembly. But they had many complaints about them being taken off as it made bleeding very difficult. The pointed rod was used in manufacturing to lap the poppet valve to the main body. Bruce. Quote Link to post Share on other sites
stevenphillips Posted April 20, 2021 Author Report Share Posted April 20, 2021 On 4/18/2021 at 9:30 PM, astontr6 said: In the past some re-conners would not accept back injectors that did not have the pointed rod. There was a phase when Lucas removed the pointed rod before assembly. But they had many complaints about them being taken off as it made bleeding very difficult. The pointed rod was used in manufacturing to lap the poppet valve to the main body. Bruce. Thank you Bruce that makes sense Quote Link to post Share on other sites
astontr6 Posted April 21, 2021 Report Share Posted April 21, 2021 On 4/18/2021 at 7:58 AM, marting said: Hi Steven I have just had a rummage through my box of old injector collars. I have some of the design that are the same as yours. If you PM your address to me I will send you one out. Martin (Fred Millturn Parts) The key issue with the non-threaded types is how good the interference fit is to the body of the injector? Basically the hole in the bush needs to be the very nearly the same size as the body. It s/b an air tight seal ! If not it can be a b------ to remove if you have a problem with that injector, especially when the engine is hot. I do not know how good Fred Millturn parts are? I had a problem in the past where the O ring groove was not concentric to the outside body and the o ring kept on trying to ride out as I pushed the injector in. I had to put the nylon bushes in a lathe to correct this problem. I came across this problem again last year on another car that was not mine. Bruce. Bruce. Quote Link to post Share on other sites
JohnC Posted April 21, 2021 Report Share Posted April 21, 2021 Is the fit between injector and throttle body/ bush a big issue? I'm really not sure, but I do wonder if the air leaking past is pretty insignificant... Quote Link to post Share on other sites
Waldi Posted April 21, 2021 Report Share Posted April 21, 2021 I think the fit is “ok” as long as the o-ring gets compressed just a little bit. But I feel it is important to have an o-ring on each adapter, as leakage during idling will be highest. Waldi Quote Link to post Share on other sites
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