My M25xp has been starting really roughly with lots of white smoke for maybe 15 seconds when cold. I replaced the glow plugs, and that really smoothed things out.
I thought members might be interested in how I found the glow plugs. The original plugs were made by ngk. The Kubota D950 part manual listed them as part #15951-6551-0. I found a glow plug cross reference table in [url]www.ngkpartfinder.co.uk[/url] that indicated that a ngk model Y-103V should work. I found this glow plug at Amazon.com for $6.78 each and ordered 3. They fit and worked perfectly.
I am not sure these are exactly like the originals because the V in the model number indicates that these are "rapid heating" plugs developed to reduce emmisions. I don't know if the originals had this feature. Does anyone know?
Gary Teeter
"AnnieG"
1989 C36 w/M25xp
Everett, WA
Gary Teeter
1989 C36 "AnnieG"
Std Rig #966, M25xp
Everett, WA
Gary,
I can not answer your question regarding the glow plugs, glad to hear it starts better. I am currious, did the white smoke diminish after start?
White smoke usually indicates water present in combustion. Are you loosing any coolant?
Cepheus dream
C36 MK I # 825
MK I Tech Editor No Mas
I have not noticed any coolant loss. During the rough starts the engine was definitely running on less than 3 cylinders. As soon as the other cylinder started firing, the white smoke went away. I assume the white smoke was unburned fuel.
Gary Teeter
1989 C36 #966
AnnieG
Everett, WA
Gary Teeter
1989 C36 "AnnieG"
Std Rig #966, M25xp
Everett, WA
Gary I have to side with you about the unburnt fuel. As if one ever looks at a truck stop and the trucks sitting there you can tell what ones have just started up and are cold. My John Deere does that same thing until it get warm. Then the smoke clears. Same thing at tractor pulls, they ramps up the rpms of the diesel until the smoke turns white then they start pulling. Thus having all the fuel they need to pull. JMO
Randy
Randy Sherwood
Mutualfun 1990 # 1057
T/R W/K M35a
Home. Charlotte, Mi.
Boat. St Augustine,Fl.
Gary,
It may be unburnt fuel if it is momantary though black would be what I would expect. If your engine continues to run rough, on less than three cylinders shortly after start, you could have other issues. Our diesels are compression ignition engines, so it is not like you get a fouled spark plug that clears up on a gas engine. If it is not firing on all three after start one cylinder is not getting enough compression to fire or you have an injector problem.
I have a compression test set you are welcome to borrow to check your compression. I would suggest it as the problem will not cure itself and may cause more costly damage over time. Low compression could be caused by a valve that needs adjustment and easy and cheap fix. It could be a burn't valve that would be easier to fix than waiting until you burn a piston at which time you would need to tear the whole engine down. It may be a fouled injector causing a bad spray pattern. If the injector can be cleaned and cure the problem this to is an easy and cheap fix even replacing the injector is not a big cost. You would need to pull the injectors to complete a compression check anyhow.
Or maybe your problem went away and I will shut up.
Cepheus dream
C36 MK I # 825
MK I Tech Editor No Mas
Steve,
Thanks for the offer of a compression tester.
I will know if the starting problem is completely solved in a week or so when I can get back to the boat. A couple of days after installing the new glow plugs the motor started fine. I am hopeful that after setting for a few weeks it will still start good.
The valves and so forth should be OK. I had a cracked head last year, and installed a new head, valves, seals, etc.. I have put a couple hundred hours on since then, and have good power.
I think the cracked head was caused by lack of maintenance by the previous owner. There was heavy corrosion of the aluminum cooling system parts on the front of the engine. When I removed the cylinder head I found that one of the small coolant passages on the front of the head was completely blocked with aluminum corrosion products. The blocked passage would have reduced coolant circulation in the head. My guess is that all of this problem was caused by the antifreeze not being maintained.
Gary Teeter
1989 C36 "AnnieG"
Std Rig #966, M25xp
Everett, WA