Denis Posted May 11, 2013 Report Share Posted May 11, 2013 My car has had an intermittant misfire, for some time, so I did all the usual stuff...Compression test on all cylinders which were all good..New Plugs, Points, Condensor, new Copper HT leads, new Dizzy Cap, new LT leads...that worked on the test run...then the problem became permanent 5 cylinders!...So I did the Injectors spray test...all good except Number 2 dribbled, so fitted a new injector....Still only ran on 5 cylinders! So, I detached No.2 fuel line from the MU...and found no fuel was coming through at all ! So...what next? Replace the Metering Unit?...Not a job I've ever had to tackle myself in the 41 years I've owned my car...So my question is to those of you who have...Are Exchange Units Calibrated and set-up to just bolt on and go?...Or is it a specialist job? Quote Link to post Share on other sites
stuart Posted May 11, 2013 Report Share Posted May 11, 2013 That will be the Number 2 banjo bolt has jammed shut. Stuart. Quote Link to post Share on other sites
RobinTR6 Posted May 11, 2013 Report Share Posted May 11, 2013 OK first it may be the injector. Swap it with another and see if the problem moves with the injector. If it works on another cylinder it may be the banjo non return valve in the MU. Not sure how you can check that tho, no doubt others will know or do a search. If the MU needs replacing , or indeed you need a new injector or banjo try Neil Raven Smith on this forum. He know all to do with the PI setup, and replaces and recons all the components at a sensible price. Hes also very helpful. If you look at posts on P|I problems I'm sure you'll find a phone number for him too. Its not difficult o replace the MU, probably between 1 and two hours. Its basically undo the bolts, remove it, remove the injector leads, connect to new MU and reconnect (including drive dog). It will need to be bled and timed, again not difficult. I'd talk to Neil in the first instance having done the above check. Quote Link to post Share on other sites
John Harvey Posted May 11, 2013 Report Share Posted May 11, 2013 I replaced both the banjo bolts on my mu yesterday. You need to take plug leads off nos 1 and 6 and with piston at tdc make sure rotor is pointing at plug lead no 1 in distributor cap. The mu is held on with three 7/16 bolts two are visible at top one is a bit fiddly underneath I managed to take out these three bolts and pull the mu away from the block without disconnecting anything else. When it is free you can undo the banjos and replace with new or reconditioned complete with new o rings. You will need a new o ring from mu to distributor pedestal and be careful the drive dog does not fall out I put mine back together and found the drive dog on the floor best to put a smear of grease on it to keep it in the mu. Hope this is helpful. Quote Link to post Share on other sites
Denis Posted May 11, 2013 Author Report Share Posted May 11, 2013 Thanks...Could you send her round...that'll fix it! Quote Link to post Share on other sites
Kevo_6 Posted May 11, 2013 Report Share Posted May 11, 2013 Hi Denis I had a similar problem last year and had my MU reconditioned by Neil Ferguson ( K Raven-Smith), nice job and very reasonably priced. His number is 07977 001571 if you should need it. Quote Link to post Share on other sites
marki Posted May 11, 2013 Report Share Posted May 11, 2013 Another vote for Neil. Sorted me out no problems.. Good luck Mark. Quote Link to post Share on other sites
peejay4A Posted May 11, 2013 Report Share Posted May 11, 2013 Why spend on an MU when it's 99% sure to be a banjo bolt? Quote Link to post Share on other sites
Kevo_6 Posted May 11, 2013 Report Share Posted May 11, 2013 If you should need it :-) Quote Link to post Share on other sites
peejay4A Posted May 12, 2013 Report Share Posted May 12, 2013 Quite so. I expect that Neil also sells banjo bolts. Quote Link to post Share on other sites
k_raven_smith Posted May 12, 2013 Report Share Posted May 12, 2013 I do Quote Link to post Share on other sites
k_raven_smith Posted May 12, 2013 Report Share Posted May 12, 2013 I do Quote Link to post Share on other sites
TR NIALL Posted May 12, 2013 Report Share Posted May 12, 2013 I do Neil's on Honeymoon,He just got Married again Quote Link to post Share on other sites
k_raven_smith Posted May 12, 2013 Report Share Posted May 12, 2013 No im not and no i havent.neil Quote Link to post Share on other sites
Denis Posted May 13, 2013 Author Report Share Posted May 13, 2013 Hahaha I've always wanted to play a musical instrument!...Banjo it is then! Thanks to all above, I'll let you know how I get on in due course! Quote Link to post Share on other sites
Denis Posted May 20, 2013 Author Report Share Posted May 20, 2013 (edited) I replaced both the banjo bolts on my mu yesterday. You need to take plug leads off nos 1 and 6 and with piston at tdc make sure rotor is pointing at plug lead no 1 in distributor cap. The mu is held on with three 7/16 bolts two are visible at top one is a bit fiddly underneath I managed to take out these three bolts and pull the mu away from the block without disconnecting anything else. When it is free you can undo the banjos and replace with new or reconditioned complete with new o rings. You will need a new o ring from mu to distributor pedestal and be careful the drive dog does not fall out I put mine back together and found the drive dog on the floor best to put a smear of grease on it to keep it in the mu. Hope this is helpful. Yes John, very helpful thank you, only I found I didn't have enough leverage with the MU hand held and spanner in the other! ...So I devised a cunning plan...I ground down my 3/4" Ring Spanner and bolted the MU back to the Pedastal with the 'thin' Ring Spanner on the No.5 Banjo Bolt, so was able to crack it free, then proceeded to do the same to No.2. Interesting to see how the old 'O' Rings had perished...the insides of the Banjo's were full of black bits of rubber, which I had noticed in the old Injectors! More updates to follow, as I've taken the opportunity with the fuel lines out the way to take the Rocker box off for a much needed respray! Edited May 21, 2013 by Denis Quote Link to post Share on other sites
Steves_TR6 Posted May 21, 2013 Report Share Posted May 21, 2013 This is contagious ! My 6 has gone from running perfectly to running on 4/5 occasionally 6 :-( I'm suspecting Banjos or Injectors being as the fault was so sudden, prob Banjos. I shall no doubt be placing an order with Neil very soon ( had a MU and Injectors from him for the last 6 and service/quality excellent) Steve Quote Link to post Share on other sites
Andy Moltu Posted May 21, 2013 Report Share Posted May 21, 2013 I'm puzzled - just how does the bamjo bolt fail? It may get clogged with bits from the seals but fail? The likelihood is that the injector has got clogged with a bit of debris from one or other of the seals in the metering unit - this tends to afflict Nos 2 & 5 because of where the are. The first line of attack is to blow out the injector with an air line to clear the debris, put it back on & wait for it to bleed. If that doesn't work swap the injector for another - that will identify if it is the injector at fault or at the metering unit end - although 99% of the time it will be a blocked injector. If it keeps blocking up you may need to replace the seals in the metering unit or have the unit rebuilt. Quote Link to post Share on other sites
Denis Posted May 21, 2013 Author Report Share Posted May 21, 2013 I'm puzzled - just how does the bamjo bolt fail? It may get clogged with bits from the seals but fail? The likelihood is that the injector has got clogged with a bit of debris from one or other of the seals in the metering unit - this tends to afflict Nos 2 & 5 because of where the are. The first line of attack is to blow out the injector with an air line to clear the debris, put it back on & wait for it to bleed. If that doesn't work swap the injector for another - that will identify if it is the injector at fault or at the metering unit end - although 99% of the time it will be a blocked injector. If it keeps blocking up you may need to replace the seals in the metering unit or have the unit rebuilt. I had fitted a New Injector to No.2...but no fuel came through at all...it was Stuart that alerted me to the fact that 'Banjo Bolts can get stuck shut'...Looking through the fuel holes in the Banjo Bolt one can see they have a spring loaded valve inside them...presumable it's a non-return valve that can fail shut? That's why I'm changing them both! Quote Link to post Share on other sites
peejay4A Posted May 21, 2013 Report Share Posted May 21, 2013 (edited) I'm puzzled - just how does the bamjo bolt fail? It may get clogged with bits from the seals but fail? The likelihood is that the injector has got clogged with a bit of debris from one or other of the seals in the metering unit - this tends to afflict Nos 2 & 5 because of where the are. The first line of attack is to blow out the injector with an air line to clear the debris, put it back on & wait for it to bleed. If that doesn't work swap the injector for another - that will identify if it is the injector at fault or at the metering unit end - although 99% of the time it will be a blocked injector. If it keeps blocking up you may need to replace the seals in the metering unit or have the unit rebuilt. I'd assumed that the banjo bolt internal valve had not clogged but jammed shut, as Stuart suggested early in the thread. They must be made differently to the non-return valves on the other injector lines if it is only 2 and 5 that tend to fail shut. Interestingly the BL WSM faulting section lists failed O-rings on the banjo connections as a cause of plug fouling on cylinders 2 and 5 and I can't make out the logic of that. Also it says that failure to inject can be due to a failure of any of the non return valves, not just the banjos. Edited May 21, 2013 by peejay4A Quote Link to post Share on other sites
Denis Posted May 21, 2013 Author Report Share Posted May 21, 2013 (edited) In my case I had been experiencing an intermitant misfire on No.2 for some time, then recently no running on that cylinder...so whilst I was going through the usual steps, I ended up changing No.2 Injector and No.5 which was my only other early 'screw-in' type...Whilst the M/U was off it made sense to change both of their Banjo bolts. Hopefully It'll be the cure...tba! Edited May 21, 2013 by Denis Quote Link to post Share on other sites
Steves_TR6 Posted May 25, 2013 Report Share Posted May 25, 2013 So, finally got the bonnet up on the 6 this morning. Being as '9 out of 10 injection problems are ignition' I first took all the plugs out. BP6es plugs all had good gaps and were nice colour, even 5 and 6 but then I don't drive the car around town much. Next I checked the pulses, all good except no 3 Out with the injectors and nothing coming out of no 3, others quite a nice spray. Swapped no 3 to no 4, and then to no2, and yes the problem moves with it. The nice tours all look quite ropey so...... Call Neil , K Raven Smith, he's putting a set n the post for me this morning. What a star that man is, thanks a million Neil. Shall report back when the injectors are fitted, fingers crossed. Steve Quote Link to post Share on other sites
Denis Posted May 25, 2013 Author Report Share Posted May 25, 2013 (edited) Finally back in the garage to tomorrow...the fiddle bit trying to keep the O Ring in place whilst locating the Dog Drive! Not looking forward to it with my old arthritic fingers...wish me luck...I'll use grease as suggested by John Harvey! Edited May 25, 2013 by Denis Quote Link to post Share on other sites
John Harvey Posted May 25, 2013 Report Share Posted May 25, 2013 Thats the way Denis you can't beat a blob of grease on the end of it Quote Link to post Share on other sites
Denis Posted May 26, 2013 Author Report Share Posted May 26, 2013 Haha...well it worked well...I'm no longer a MU Virgin! Quote Link to post Share on other sites
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