zen rajab Posted July 14, 2017 Report Share Posted July 14, 2017 Can any one please instruct me through increasing the rpm of my lister sr2 engine Link to comment Share on other sites More sharing options...
Tony Brooks Posted July 15, 2017 Report Share Posted July 15, 2017 Open the "throttle". To try to be a bit more helpful please explain exactly what you mean. Some Listers from the likes of generators are fixed speed machines so need modifications to turn them into multi-speed ones. If the engine is simply not going fast enough for your taste and you want t to go faster then it might be a prop problem, and adjustment problem, or you are already at the maximum design speed of the engine. More info needed, including numbers if you have them. Link to comment Share on other sites More sharing options...
zen rajab Posted July 15, 2017 Author Report Share Posted July 15, 2017 My lister is sr2 twin cylinder I am using it with a generator that is 1500 rpm but apperantly the engine is set to 1000 rpm Link to comment Share on other sites More sharing options...
PhilAtterley Posted July 15, 2017 Report Share Posted July 15, 2017 Hello to you. The first two photographs aren't really any use - they just show the part number for the fuel injection pump housing, but the others are good and show that your engine is a fixed speed build, and the photo of the maker's plate confirms that it was set to run at 1500 rpm at the factory, so there are some more things you must consider before adjusting the governed speed : What is the maximum load you are applying ? Is the engine running correctly, with a clean exhaust both on and off load ? Have you checked the full load and off load rpm with a hand-held rev-counter ? Link to comment Share on other sites More sharing options...
zen rajab Posted July 15, 2017 Author Report Share Posted July 15, 2017 i did use a rev counter and the reading was 1412 rpm OFFLOAD and at 50% load the reading was 1386 rpm Link to comment Share on other sites More sharing options...
PhilAtterley Posted July 15, 2017 Report Share Posted July 15, 2017 (edited) 20 hours ago, zen rajab said: i did use a rev counter and the reading was 1412 rpm OFFLOAD and at 50% load the reading was 1386 rpm In the 4th photo from the top there are two nuts (7/16 ths AF) locked together on what appears to be a stud which should have a screwdriver slot cut into the end of it - this is the control rod for the governor speeder spring. Using two slim open ended spanners, or one slim open ended spanner and a ring spanner or socket, hold the inner nut still and loosen the outer nut half a turn, then loosen the inner nut by a quarter turn. Then, while preventing the inner nut from turning with a spanner, rotate the control rod anti-clockwise to increase the governed speed. With the speed set correctly re-lock the inner nut to the timing case then both nuts together without disturbing the setting. If you find that the control rod will rotate after unlocking only the outer nut, then it means that the timing case cover on that engine has been fitted with an internally and externally threaded sleeve for the speeder spring rod (to replace the original tapped thread in the cast ally timing cover. Adjustment remains as before, and you will need to rotate the control rod anti-clockwise (by means of the screwdriver slot) to increase rpm. Edited July 16, 2017 by PhilAtterley Link to comment Share on other sites More sharing options...
zen rajab Posted July 15, 2017 Author Report Share Posted July 15, 2017 I have checked the control rod and it has no screw driver slot cut in it Link to comment Share on other sites More sharing options...
Tony Brooks Posted July 16, 2017 Report Share Posted July 16, 2017 Do you have a hacksaw? If so make one. Link to comment Share on other sites More sharing options...
zen rajab Posted July 16, 2017 Author Report Share Posted July 16, 2017 could i just grab it with a lock pliers? Link to comment Share on other sites More sharing options...
Tony Brooks Posted July 16, 2017 Report Share Posted July 16, 2017 And probably wreck the thread so the nuts will not unscrew - yes if there is enough of a stub to grip but I would not for the sake of a minutes work with a small hacksaw. Link to comment Share on other sites More sharing options...
zen rajab Posted July 16, 2017 Author Report Share Posted July 16, 2017 I have loosened the nuts and rotated the thread by hand clockwise and anti-clockwise but nothing happened it just kept on turning Link to comment Share on other sites More sharing options...
PhilAtterley Posted July 16, 2017 Report Share Posted July 16, 2017 1 hour ago, zen rajab said: I have loosened the nuts and rotated the thread by hand clockwise and anti-clockwise but nothing happened it just kept on turning If rotating the (threaded) speeder spring link/control rod had no effect on rpm then that indicates that the female thread in the cast aluminium timing case cover has stripped - which is probably why there are two nuts on it now, instead of the single nut fitted originally at the works. Link to comment Share on other sites More sharing options...
Tony Brooks Posted July 16, 2017 Report Share Posted July 16, 2017 23 minutes ago, PhilAtterley said: If rotating the (threaded) speeder spring link/control rod had no effect on rpm then that indicates that the female thread in the cast aluminium timing case cover has stripped - which is probably why there are two nuts on it now, instead of the single nut fitted originally at the works. If that is a correct diagnosis and if my understanding of the adjustment is correct then the OP may be able to alter the speed by loosening the lock nut, using the second nut to "pull" the adjustment out or allow it to go in That should adjust the speed. Then lock it up again Link to comment Share on other sites More sharing options...
PhilAtterley Posted July 16, 2017 Report Share Posted July 16, 2017 (edited) 18 minutes ago, Tony Brooks said: If that is a correct diagnosis and if my understanding of the adjustment is correct then the OP may be able to alter the speed by loosening the lock nut, using the second nut to "pull" the adjustment out or allow it to go in That should adjust the speed. Then lock it up again That's right, Tony, the state of the nuts in the photo suggests that the rpm setting has been clumsily messed about with before. The thread in the ally casing is quite a fine pitch and easily stripped with over enthusiastic tightening of the original single locknut. The control/link rod passes through the coils of the (tension) speeder spring and the inner round headed end of it, which also has a screwdriver slot, is retained in place attached to the spring by a couple reduced diameter coils on the end of it. The other end of the speeder spring hooks onto the pump racks adjacent to the governor arm. Edited July 16, 2017 by PhilAtterley Link to comment Share on other sites More sharing options...
Tony Brooks Posted July 16, 2017 Report Share Posted July 16, 2017 Thanks Phil, so the OP has an idea about what to do Cheers. Link to comment Share on other sites More sharing options...
PhilAtterley Posted July 16, 2017 Report Share Posted July 16, 2017 41 minutes ago, Tony Brooks said: Thanks Phil, so the OP has an idea about what to do Cheers. Maybe ? - but I do get the impression that he isn't paying too much attention to what he's being told ! Link to comment Share on other sites More sharing options...
zen rajab Posted July 16, 2017 Author Report Share Posted July 16, 2017 So please give me the short version of what to do to fix the problem Link to comment Share on other sites More sharing options...
Tony Brooks Posted July 17, 2017 Report Share Posted July 17, 2017 Er - contact your local Lister specialist. If this engine is in the same location as given in your profile I fear we have no way of knowing what has been done to the engine to keep it running in the past. All sorts of novel solutions to problems may have been tried. 1. cut a slot in end of the shaft that comes out through the nuts. 2. Hold the inner nut and loosen the outer lock nut. 3. Use slot to hold the shaft still and rotate the inner nut. It should pull the shaft slightly out of the engine if the casing thread has stripped or allow it to move back in. Do this with the engine running so you can judge its effect. 4. If successful tighten lock nut. 4b. If not successful something is probably wrong inside the engine so if you can not fix it go to top of this answer. Link to comment Share on other sites More sharing options...
zen rajab Posted July 17, 2017 Author Report Share Posted July 17, 2017 (edited) I have made the slot cut in the rod But i have noticed that the rod when revolved comes out and when thightening the inner nut the rod is not moving in or out the casing Edited July 17, 2017 by zen rajab Link to comment Share on other sites More sharing options...
PhilAtterley Posted July 17, 2017 Report Share Posted July 17, 2017 (edited) 1 hour ago, zen rajab said: I have made the slot cut in the rod But i have noticed that the rod when revolved comes out and when thightening the inner nut the rod is not moving in or out the casing This is all good news for you - the control rod should move in or out as it is rotated to either decrease or increase the tension on the governor speeder spring. The fact that it is doing this means that the thread in the bush (in the timing cover) that the control rod passes through is intact and functioning as intended, so you can now re-set the governed rpm. by turning the control rod anti-clockwise (outwards) to increase the revs and clockwise (inwards) to decrease. I suggest 1570 - 1580 rpm off load as the initial setting, then recheck on load (preferably full load - 7 KVA max. continuous for the SR2) and re-adjust if necessary. Edited July 17, 2017 by PhilAtterley Link to comment Share on other sites More sharing options...
zen rajab Posted July 17, 2017 Author Report Share Posted July 17, 2017 That did the trick Thank you very much for your help I owe you bigtime guys Link to comment Share on other sites More sharing options...
PhilAtterley Posted July 17, 2017 Report Share Posted July 17, 2017 13 minutes ago, zen rajab said: That did the trick Thank you very much for your help I owe you bigtime guys Glad you've got it sorted out. Just out of interest, what sort of alternator are you running off the SR2 , and is it close-coupled or belt-driven off the flywheel end ? Link to comment Share on other sites More sharing options...
zen rajab Posted July 17, 2017 Author Report Share Posted July 17, 2017 (edited) I am using a 12kw synchronous alternator close-coupled to the engine but never load it more than 30 amps Edited July 17, 2017 by zen rajab Link to comment Share on other sites More sharing options...
PhilAtterley Posted July 17, 2017 Report Share Posted July 17, 2017 (edited) 28 minutes ago, zen rajab said: I am using a 12kw synchronous alternator close-coupled to the engine Take care not to exceed a total connected load (in KW's) of :- 7 x Alternator Power Factor (work on 0.8 PF if no other info.) The close-coupled alternator you're using prompts me to ask where you've been using the hand-held rev-counter, and if you have been using the camshaft extension at the timing case end for rpm testing/setting on the assumption that it was the crankshaft ? If you have, and you've got it set with that running at 1500 rpm, then you've got the engine and the alternator turning at 3000 rpm ! Edited July 17, 2017 by PhilAtterley Link to comment Share on other sites More sharing options...
zen rajab Posted July 17, 2017 Author Report Share Posted July 17, 2017 I used the rev counter on the fly wheel end of the shaft (The coupling between the alternator and the engine is exposed and not covered or protected by a cover or any thing) Link to comment Share on other sites More sharing options...
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