rovercoupe Posted April 8, 2018 Report Share Posted April 8, 2018 Had a look at my neighbors mower after he said it was playing up after being stored all winter and it will start and run badly on full choke and then die after a few seconds so i thought it was just the carb needin to be cleaned out and new fuel putting in but after doing that it still would not run. I swapped the carb for a honda one that fitted but was not right for it and it pretty much did the same so have ruled the carb out. Did a compression test and only got 80 psi so thought stuck valve and started to look there which is when i noticed a click on the exhaust valve when turning over by hand. Its not the valve sticking as the pushrod is dropping like a stone when its turned over. Having not worked on these hondaish engines I don't know if this is normal or not, im thinking there is somthing really wrong with the engine cam lobe or the rod itself is wrecked. It does push the exhaust valve when turned over though. video below of the valve noise, any thoughts guys? Quote Link to comment Share on other sites More sharing options...
eastdevon Posted April 8, 2018 Report Share Posted April 8, 2018 How long has the engine been sat up for?? You say you have ruled out the carb?!? Is the air filter ok as in clean enough?? Did you blast out the fuel jets within the carb as they are a ****** for getting clogged up! As for the ticking sound it sounds to me like it has a sticky push rod lifter which should cure itself with a couple of heat cycles. Also these small engines sometimes do have a small catchment on the cam which holds a valve open very slightly for longer which helps lower the compression to aid in easy starter in the pull rope, once running this is flung open and away so that normal valve function and compression is resumed for running. Oh and if spark plug is old and full of crud replace with a new one, old cruded up ones can and do make starting and running a ******. Quote Link to comment Share on other sites More sharing options...
snow white Posted April 8, 2018 Report Share Posted April 8, 2018 Could be the petrol as deterated over the winter it happens a lot with boat engines when some body does not winteris there engines properly when leaving for long time with carb engins run it till carb is empty then take plug out ut i little squirt of oil in plug hole replace plug then spray winteriser in carb fine to go next time you want to use it i had about for 35 years no problem Quote Link to comment Share on other sites More sharing options...
rovercoupe Posted April 8, 2018 Author Report Share Posted April 8, 2018 The neighbor changed the fuel, i also drained the carb and cleaned it and put in fresh fuel to make sure and no joy. I did think about it being somthing to do with decompression which was why it's pressure is at 80 psi i did try a bit of easy start when it was spluttering and it made no difference to the running so I just dont think its the carb even though everything points to it being fuel starvation. Quote Link to comment Share on other sites More sharing options...
eastdevon Posted April 8, 2018 Report Share Posted April 8, 2018 (edited) 4 minutes ago, rovercoupe said: The neighbor changed the fuel, i also drained the carb and cleaned it and put in fresh fuel to make sure and no joy. I did think about it being somthing to do with decompression which was why it's pressure is at 80 psi i did try a bit of easy start when it was spluttering and it made no difference to the running so I just dont think its the carb even though everything points to it being fuel starvation. Could you if possible post us a video of you starting it so can hear and see what is happening exactly? What is the Honda engine model number!! Edited April 8, 2018 by eastdevon Add detail Quote Link to comment Share on other sites More sharing options...
rovercoupe Posted April 8, 2018 Author Report Share Posted April 8, 2018 The mower is back with the neighbor now, when starting it would just hunt and not idle and then die, just like its fuel starved thats about the best i can describe it without being able to video it! Its a mountfield engine but it seems to be quite hondaish in looks and parts. Quote Link to comment Share on other sites More sharing options...
eastdevon Posted April 9, 2018 Report Share Posted April 9, 2018 Could possibly be the governor arm needs adjusting. Quote Link to comment Share on other sites More sharing options...
decoy1979 Posted April 9, 2018 Report Share Posted April 9, 2018 Is it possible that the fuel that was changed was from a can that's been sat in the shed from last year rather than truely fresh fuel? Quote Link to comment Share on other sites More sharing options...
kenholland Posted April 9, 2018 Report Share Posted April 9, 2018 I always put a drop of choke and carb cleaner in with the fresh petrol every now and again ,they can be a pain over the winter period when stored , it happens to a lot of people. Quote Link to comment Share on other sites More sharing options...
Dave-G Posted April 9, 2018 Report Share Posted April 9, 2018 Sounds just like an issue I had after the winter lack of use. Turned out the rubber diaphragm had dried out and cracked. Time to take the carb apart till you get that far. Quote Link to comment Share on other sites More sharing options...
haynes Posted April 9, 2018 Report Share Posted April 9, 2018 If it went into hibernation ok last year. Then chances are somethings sticking but not anything that a few runs with fresh fuel shouldn't solve. Quote Link to comment Share on other sites More sharing options...
rovercoupe Posted April 9, 2018 Author Report Share Posted April 9, 2018 The carb is gravity fed and has been stripped and cleaned, i put in good fresh fuel, checked flow from tank and the float bowl is good. lost on it really but the neighbor is thinking of cutting his losses and buying a new one so will have to see if the dealer thinks its worth repairing. Quote Link to comment Share on other sites More sharing options...
eastdevon Posted April 9, 2018 Report Share Posted April 9, 2018 There one tip my grandad gave me about petrol mowers, that was to not just clean it and put it away for the winter months left idle. He basically told me to put the mower deck on to its highest setting so blade was well away from the garage floor and every couple of weeks just pop over to the garage and fire it up and let it run for ten minutes. Doing this puts engine in constant use and keeps it all healthy as nothing will dry up/sieze up! Pulled mine out today, filled up with some more fresh fuel, changed the oil, new spark plug, cleaned airfilter.... Primed the pump three times and first pull vroooooooom!!! My neighbour on the other hand stood with his pulling starter over and over again!!! Quote Link to comment Share on other sites More sharing options...
rovercoupe Posted April 10, 2018 Author Report Share Posted April 10, 2018 or use a genuine honda gx engine or even a g series if you clean the points once in a while! Not herd anything back yet so dont know what the problem is, I would like to know what it was though. Quote Link to comment Share on other sites More sharing options...
lister1 Posted April 11, 2018 Report Share Posted April 11, 2018 These are a poor Honda copy, made in China. They suffer from sticking valves and often need the over head valve pushers adjusting. Quote Link to comment Share on other sites More sharing options...
bornfree Posted April 11, 2018 Report Share Posted April 11, 2018 12 minutes ago, lister1 said: These are a poor Honda copy, made in China. They suffer from sticking valves and often need the over head valve pushers adjusting. as above. especially when they havent been used for a while. stand the engine so the valves face downwards and spray WD40 down the stem and tap the valve gently. it should free off. Quote Link to comment Share on other sites More sharing options...
rovercoupe Posted April 16, 2018 Author Report Share Posted April 16, 2018 Right its back with me, next door have given it to me as the dealer wanted too much to investigate it, so had the rocker cover off and checked the valves and they are not sticking, the click is 100% coming from the engine, I can feel it through the pushrod, i also held the governor and cannot feel the click through the arm. The engine is going to be a pig to take apart but I think its the only way to find out whats wrong but the question still remains, do we think that click is normal? i have a video of it running, choke and throttle position make no difference allthough it did run better with a bit of carb cleaner through it but easy start stalls it! I am thinking there is a carb issue so have that off and will soak it and see what happens. Could the click just be how the engine runs given its a hongda??? Quote Link to comment Share on other sites More sharing options...
johnphilip Posted April 17, 2018 Report Share Posted April 17, 2018 Just a thought , its not the primer bulb is it .it does sound like its starved of fuel Quote Link to comment Share on other sites More sharing options...
dead eye alan Posted April 17, 2018 Report Share Posted April 17, 2018 Sounds like a broken valve spring to me, sometimes springs just break for fun. Quote Link to comment Share on other sites More sharing options...
rovercoupe Posted April 17, 2018 Author Report Share Posted April 17, 2018 No primer on this its a gravity fed carb, there are no springs on the pushrod side and thats where the click is coming from, going to ponder this one at work and see what I can come up with! Quote Link to comment Share on other sites More sharing options...
la bala Posted April 17, 2018 Report Share Posted April 17, 2018 Are the rocker arms pressed steel? I had a clicking problem years ago, I am sure it was something to do with the rocker arm. Quote Link to comment Share on other sites More sharing options...
Walker570 Posted April 17, 2018 Report Share Posted April 17, 2018 I'm not kidding. Check the exhaust pipe for a small leak. I recently started my Land Rover (4ltr V8) and there was a distinctive TICK TICK TICK at regular intervals. Fearing valve or valve followers, I gently drove it to my garage. He lifted the bonnet and pointed to a small 1/4 inch hole in one of the down pipes. Seeing that I have multi piped headers fitted meant this TICK only occurred when that cyclinder exhausted. Relief. Just check, it could be that simple. Quote Link to comment Share on other sites More sharing options...
rovercoupe Posted April 17, 2018 Author Report Share Posted April 17, 2018 Rocker arms are cheepy pressed steel, took them off last night to check and then reset the them and the exhaust is like new but I have a theory................... I have found a image of the engine and I think I might have found the problem, it looks like there is some form of decompression setup on the valve cam itself, I think its either stuck or fallen apart and is causing the pushrod to click. Having not seen this on any of the older honda engines I have rebuilt so its a new thing to me. This could be whats lowering the compression and not knocking off when it starts causing it to run like bobbins. The only downside is its a full disassemble job to get to it and if its shanked then I will rip it out and try it without! Quote Link to comment Share on other sites More sharing options...
eastdevon Posted April 17, 2018 Report Share Posted April 17, 2018 After listening to engine running and what you have just said I think you could be right, had same sort of sound on my Briggs and Stratton classic engine and did same, stripped down and removed the decompression bit which yes did stop the noise and yes the engine ran perfect but after a few times use decided to reinstall a new one as the pull over to start was harder and if engine kicked back ****** me it hurt me hand!!! Quote Link to comment Share on other sites More sharing options...
rovercoupe Posted April 17, 2018 Author Report Share Posted April 17, 2018 Can I ask was the decompression part damaged in any way on yours or just stuck? I have had some evil kickback on my big milling saw when it was running lean and it nearly snapped my arm off. Quote Link to comment Share on other sites More sharing options...
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