HI Guys / Girls.... We have recently purchased 2 brand new aksa gensets...710kva. DP180LB DOOSAN V10.... The engines have only covered 1500hrs each....they both have shaken the thin safety guards to bits.....crank dampner metal fins have broken off......but most seriuosly both have recently suffered bent push rods to the valves (inlet and exhaust).... A doosan engineer replaced the push rods and after approx 150hrs same problem has occurred on same cylinder and also next cylinder......also the other engine has bent push rods on one cylinder aswell !!!!!! What on earth is going on ?? not familiar with these engines much.......not even 6 months old and have this happening....Valve clearances on other cylinders seem ok.......they are very basic mechanical engine.....what is causing the problem here ? doosan recommend 10/40 engine oil.....I believe 15/40 oil was used...Morris' 15w/40.....would this be a problem ? The balls on end of rockers seem to be damaged aswell. Are the push rods poor or weak metal ? Not sure if a piston has hit any valves. After the doosan engineer refitted the damaged push rods the engine seemed to run ok for the next 150 hrs. The engines run at 1500rpm on genset application. fuel tanks were fed from a large bulk tank , now changed back to chassis tanks in genset chassis....would that make a difference ...? Maybe dodgy sticking cam followers ? sticking valves ? weak valve springs ? Any one know about these engines or problems ? appreciate your knowledge of any quality cheers J.S
Welcome to HEF Justyn ! Seem OK or were they actually measured and are OK? My first thought is valve adjustment, valve stem clearance issue, side to side movement of the rocker arm, weak valve spring or maybe a sticking lifter. Since it is in a genset I doubt it would be overspeed. Hopefully someone with some Doosan experience will chime in. With those low hours and repeating issue I would be reaching out to Doosan themselves, either through your dealer or directly.
Hi,the rest of the clearances were ok, checked...there is a little movement in the side to side of the rocker arms but within the tolerances of the book settings. Was thinking maybe followers / lifters....awaiting doosan to reply. appreciate your respnse, many thanks.
In my neck of the woods bent pushrods usually mean someone has been a little cavalier with a can of ether during a cold start. If your dampener and the guarding are coming apart though it would seem to me that there is something going on deep in basement. Do they run rough? Have you verified injection timing? What kind of climate do the engines operate in?
Pictures of the carnage would assist us in helping you.
Which particular cylinders?
Hi guys It turns out the valves in some of the cylinders are overheating and sticking in the valve guides , thus bending push rods, i found another service centre over here which suffered the same problem, they say the tolerances are not accurate enough and stiction ocurrs. I cant believe its happened to both engine units !! If anyones suffered this aswell i'd like to know more about it ? DOOSAN DP180 LB...V10 ENGINES.
cylinders 9 and 10 on the 1 engine (close to the injector pump).......only 1 cylinder on the other unit (to be confirmed which cyl later)
Makes me wonder what other tolerances are “not accurate “
Thanks for the update.
An engineer acting for doosan is going to site soon, he believes the top rockers etc are also overheating (blue colouring in metal) .....are doosan engines generally a poorer quality built engines compared to perkins,cummins, etc ? Not had many of them and probably wont in future unless this is an one off case....I hear they are popular in marine application ? cheers guys
The fact that in over 37 years of experience I have never seen one says alot. If they are used in other industrial areas I am not aware of it.
almost sounds like inadequate upper valvetrain oiling??
I ran across one of these and only one. The Airfield Maintenance Facility at TSAIA has one for backup power.
The trouble we have with sticking valves on gen sets is due to light loads causing varnish on valve stems in cold weather. Usually on the small 4 cylinder Olympian generators.
Any expanation for the vibration ?