Hi, I have a mini digger with a 3 cylinder deisel engine. From cold it starts & runs fine but after about an hours work it starts to stall very easily & is sometimes difficult to restart. Power delivery seems to get worse & worse until even using the dozer blade gently will cause a stall. Leave it overnight & it's ok again for the first hour. Any ideas please. Thanks for any advice you may have. Oh, I checked the air filter, ok & the inline fuel filter seems to contain air but I can't bleed it out.
Hi I will help with your problem Please do not rate until all your questions are answered that way you wont have to pay twice Use reply to expert link.Well I think you answered your own question on a diesel engine any air in fuel system is a problem.So we will need to start there.Do you know what type off engine is on it does it have a inline pump on it, I mean does it have three fuel lines going from pump to nozzles?Any info you can provide will help us get it running like it should.
Hi Spanky, thanks for your response.The engine is a Kubota 3 cylinder inline. There are 3 steel lines from the injector pump to the injectors. there is an electric pump which comes on with the ignition switch & an inline fuel filter between the tank & the injector pump.Fuel returns to the tank all the time the ignition is on. I have checked that the fuel is not contaminated & when I disconnected the inline filter it emptied & then refilled itself. I dont know what it did with the air when it did this.I tried loosening the supply pipe at the injector pump but no air appeared to come out, I then loosened each injector connection with the engine running to bleed them but it made no difference when retighted. I thought perhaps the fuel tank cap air hole was blocked so tried running with the cap loose but again no difference. In fact the cap doesn't have a bleed hole.I have tried running with the air filter off,no result.There isn't any visible smoke at the exhaust except on startup from cold, then it's a puff of blue presumably from of bit of oil draining down the valve guides overnight. Today after it got hot it stalled & was very difficult to restart. Fine at initial startup. When its really hot just closing the bucket is enough to stall the engine.Hope this is helpful. Regards Paul.
Yes it helps a great deal it sounds like the pump in tank is going bad.What you need to do is install a gauge [fuel pressure ] any were on suction side after pump in tank I would look at filter and see if you can install a tee that you can use to put on a gauge then when your done checking you can leave in place and cap off in case you ever have another problem.So first install a tee hook up a gauge by this time engine will have a chance to cool down,start engine and look at gauge see what you have then check at high idle record them readings then use tractor and watch gauge it will probably go down as pump heats up that will confirm your problem off the tank pump going out.If you don't see a problem get back to me through this link and we will go from there but we need to do this first,because most issues with hard starts and low power are fuel related.One last thing never ever run with air filter off it can dust your cylinder walls and then you would need a over haul.And I'm sure you don't want that expense these engines are small but parts are stupid, unrealistically, crazy high.Thank you and I hope ive answered to your satisfaction if not please come back and we will fix whatever needs to be taken care off.Even after you rate my answer you can always come back to this link to talk.Thanks again spanky
Thanks, XXXXX XXXXX that. Do I need a pressure gauge or a vacuum gauge, Is the pump the part on top of the engine with an electric cut out operated by the ignition switch? This part get very hot, too hot to touch. Very pleased with your replies. Do I rate you now or after I check pump?
You need a pressure gauge and you can rate now if you have questions on same problem next week or month you can still talk with me through this link reply to expert Thanks and have a great day spanky
I worked on all types semis,forklifts,farm,fire,ect.
Hi again I read you reply again and I thought it said you had a electric fuel pump the pressure gauge goes in after that pump before going to injection pump with lines on it.If you need more help let me know.
Hi spanky, I thought I did rate your reply, Great Service. I will try again, if you don't get paid let me know. I havn't had time to check the pump yet, hoping to get to it this weekend. Thanks again. Paul.
Not a problem and yes I did get paid I will be on line over weekend so if you have questions I will get back to you asap spanky