John L Posted April 14, 2015 Report Share Posted April 14, 2015 I have been trying to get these throttle bodies balanced, in their pairs, but its been in vain. I don't have the air bleed on the front body. Ports 1, 3 ,5 flow much less air than 2,4,6. at an idle speed of 800 - 900erpm. I have centred the plates, but this hasn't rectified the extra flow. There is some play on the new spindles, in ports 2,4,6 so I'm supposing that this is leading to the increased air flow for the even ports. I presume that I will need to get these bushed, are there any recommendations as who can do this delicate job and guarantee an equal air flow in the paired bodies? I realise that this does really only affect the idle quality, but it must have some effect on the off idle speeds up to about 1200erpm. Does anybody have a jig and lathe to do this job, as I don't have one. John Quote Link to post Share on other sites
Quentin Posted April 14, 2015 Report Share Posted April 14, 2015 Neil Ferguson reconditioned mine. Great job too. Quentin Quote Link to post Share on other sites
RobinTR6 Posted April 14, 2015 Report Share Posted April 14, 2015 Yep Neil is your man, did mine and MU etc, sensible price good work friendly and helpful....and knows his Pi stuff. Its Neil Raven Smith on this forum. Quote Link to post Share on other sites
elclem1 Posted April 14, 2015 Report Share Posted April 14, 2015 Hi I have a friend here who does mine, but postage might be a problem. Cost is £20 per body bushed. Cheers Andy Quote Link to post Share on other sites
TriumphV8 Posted April 17, 2015 Report Share Posted April 17, 2015 Ports 1, 3 ,5 flow much less air than 2,4,6. at an idle speed of 800 - 900erpm. There is some play on the new spindles, in ports 2,4,6 so I'm supposing that this is leading to the increased air flow for the even ports. I presume that I will need to get these bushed, are there any recommendations as who can do this delicate job and guarantee an equal air flow in the paired bodies? Hi John, these problems always occure when dealing with the PI. Mostly not taken that serious it affects the most time you use the engine because that fault gives uneven mixture at light part throttle. That si where we drive most of the time! One remedy is to make mixture rich in that area because too rich mixture on some cylinders is not that bad as to lean mixture on others that tend to misfire ....... Worn is the spindle itself and the manifold bore. If remedy is taken mostly only the spindles are changed what makes things better but not perfect. Bushing the manfold was yesterday, much better is to use little bearings from RC cars. The spindle moves under load much easier than with bushes. By the way, at idle the flow through the manifolds does not play that role as long as idle does not get too high. The connection between the manifold is able to compensate at that rate and gives each cylinder nearly same amount of air. The same flow must be established at engine reving about 2000 rpm. Quote Link to post Share on other sites
John L Posted April 19, 2015 Author Report Share Posted April 19, 2015 Elclem1 You a PM John Quote Link to post Share on other sites
astontr6 Posted April 19, 2015 Report Share Posted April 19, 2015 John,You need to fit the air valve as well but I don't think you can buy the body? But the screw valve and the spring can still be bought, I think that you will have to get a M/C Shop to make the body. But Chris Witor sells the other parts,he maybe a source for the body as well? He is well known for Triumph Big Saloon Parts. Bruce. Quote Link to post Share on other sites
ShaunC Posted April 19, 2015 Report Share Posted April 19, 2015 (edited) Finished rebuilding mine today, new butterfly shafts, phosphor bronze bushes (only on each end at the moment), stainless ball joints, stepped washer, zinc plated the original steel parts (although not as evenly coloured as I'd hoped! Edited April 19, 2015 by ShaunC Quote Link to post Share on other sites
TriumphV8 Posted April 20, 2015 Report Share Posted April 20, 2015 Yes, that is the next step, when the butterfly shafts are in good shape with no play and turn easy than at the CP the connection to the lower shaft and the bearings of this shaft itself are the next step. That looks like working with no play and with the stepped washers they will keep the position it is set up with. Quote Link to post Share on other sites
John L Posted April 20, 2015 Author Report Share Posted April 20, 2015 ShaunC Thanks for the photos, who did you get to drill and make the bushes for the throttle spindles, is this something you have done yourself? Who did the plating of the parts, that good as well. Can you now get even air flow in both ports of the same throttle body? John Quote Link to post Share on other sites
Andrew Smith Posted April 20, 2015 Report Share Posted April 20, 2015 I'll need to balance my butterflies and adjust the linkage shortly - apart from the 'Brown Bible', is there a decent guide or website out there? Cheers Andrew Quote Link to post Share on other sites
aardvark Posted April 20, 2015 Report Share Posted April 20, 2015 Andrew Try the 'Petrol Injection Primary Check Card' issued by Triumph. Its available on the net although I have an electronic copy too. PM me if you want a copy. Cheers Dave Quote Link to post Share on other sites
ShaunC Posted April 20, 2015 Report Share Posted April 20, 2015 I have a lathe and mill so made them myself. I have one of those synchrometers and have been able to set all 6 up pretty close. The unit measures flow, the units on the meter are kg/h. Each pulled just under 3kg/h once finally set, I was able to get them between 2.5-3 at idle. I found the best method of seating the butterflies was by slackening off the screws whilst the engine is at idle just enough to enable them to shift into position and just slightly blipping the throttle a couple of times, this seemed to be the most effective way of getting the final balance even. This was after setting the stops on the throttle shafts, observing maximum butterfly opening, synchronisation of each set.....etc. It's a bit fiddly! And there is a bit of back and forth with checking adjustments and making sure each adjustment hasn't had a negative impact on another inlet, but it didn't take too long. Quote Link to post Share on other sites
Andrew Smith Posted April 20, 2015 Report Share Posted April 20, 2015 ..............I have one of those synchrometers and have been able to set all 6 up pretty close. The unit measures flow, the units on the meter are kg/h. Each pulled just under 3kg/h once finally set, I was able to get them between 2.5-3 at idle. I found the best method of seating the butterflies was by slackening off the screws whilst the engine is at idle just enough to enable them to shift into position and just slightly blipping the throttle a couple of times, this seemed to be the most effective way of getting the final balance even. This was after setting the stops on the throttle shafts, observing maximum butterfly opening, synchronisation of each set.....etc. It's a bit fiddly! And there is a bit of back and forth with checking adjustments and making sure each adjustment hasn't had a negative impact on another inlet, but it didn't take too long. Useful info Shaun - I recently acquired a Crypton Synchro Check Meter to do the job Cheers Andrew Quote Link to post Share on other sites
Guest ntc Posted April 20, 2015 Report Share Posted April 20, 2015 Andrew Think you will find your adjustment rods will be rusted,so use wd40 overnight before you attempt this,as you know these are nla if stuck I may have some. Quote Link to post Share on other sites
Andrew Smith Posted April 21, 2015 Report Share Posted April 21, 2015 Andrew Think you will find your adjustment rods will be rusted,so use wd40 overnight before you attempt this,as you know these are nla if stuck I may have some. Thanks Neil, will let you know. Cheers Andrew Quote Link to post Share on other sites
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