Smoking During Start-Up

[Jeff]

I have a 1993 H33.5 with a Yanmar 3GM30F with unknown hours on it. My best guess is about 1000-1500. Nothing major has needed fixing on this engine. I've only replaced the fuel lines, filters, impeller, antifreeze and the oil. Just recently it's started smoking. But only during the first 15 seconds after start up and if it's sat over night or for the week. It's a white smoke and according to the manual this is unburned fuel. There are several potential reasons for this color exhaust. They list these: fuel injection timing, low compression, leaky valves, bad fuel or a defective injector. The engine runs great! I always motor at high rpm's, the antifreeze and oil look fine. Where do I start?

 

[tommays]

I would WAG and injector with a dribble as there sure due for a bench test at the very least

 

[Don S/V ILLusion]

Yanmars often blow white "smoke" at start-up and if it lasts only seconds as you said, it is hot air steam condensation. If it were the injectors or a valve, the "smoke" would not go away so quickly. I bet you see more of it as the weather starts getting cooler.

 

[Barnacle Bill]

White smoke sometimes means steam or water in the exhaust, as suggested above already, but a cause could be a leaky head gasket or warped head. Did the engine ever over heat (which could cause this)?

 

[RON20406]

Jeff, I would check two things: leaking injectors and fuel. The smoke you see may not be condensation but unburnt fuel. Also, if you have some water in your fuel and/or contaminants it could smoke temporarily when cold. I would bench test your injectors and replace/rebuild as needed, replace the washers and add a diesel fuel additive with some fresh diesel from a station that pumps a lot of fuel where you know it hasn't been sitting. This is the simplest course of action involving the least amount of money. Another area to check after that would be to test your injection pump which could be leaking fuel after shut down because of faulty check valve causing the same problem on start up. Good luck and good sailing, Ron

 

[Steve Dion]

also when you shut her down, you may want to rev her up to about 2,000 rpm in neutral and then pull the fuel shut off. This will burn any excess fuel in the cylinders.

If that does not clear this up, then you can start the discovery processes listed above.

 

[bria46]

My Mercedes Diesel man said that white smoke is caused by faulty or inoperative glow plugs. Three of the six glow plugs in my E300D were not working. When I replaced all six glow plugs (less than $15.00 each), The white smoke was gone!! My diesel guy was right!!!

 

[Jeff]

Smoking During Start-Up (Thanks)

I do appreciate all the sage advice. I've contacted a local Bosch certified company to bench test my injectors. $30 for all three. They also can check my injector pump. I priced out new injectors with a Yanmar dealer. $120.00 each. The injector pump ... wow $1114.00. I purchased some Seafoam additive for the fuel tank and will check my water seperator over the holiday weekend. Thanks for all the help.

 

[RON20406]

I do appreciate all the sage advice. I've contacted a local Bosch certified company to bench test my injectors. $30 for all three. They also can check my injector pump. I priced out new injectors with a Yanmar dealer. $120.00 each. The injector pump ... wow $1114.00. I purchased some Seafoam additive for the fuel tank and will check my water seperator over the holiday weekend. Thanks for all the help.

Jeff, in a worst case scenario, both the injectors and the pump can be rebuilt for a fraction of the cost of new ones. Ask around in your area who is "honest and reliable" if the company who's doing the testing cannot perform the rebuilds. If you don't have any luck, I 'll send you the name of a good company who is competent and fair in pricing. Don't forget, you'll also need the bronze seating washers for your installation. Good luck and good sailing, Ron

 

[RAD]

If you don't have any luck, I 'll send you the name of a good company who is competent and fair in pricing. , Ron

I'd be interested in that name for future.....are they local to us?
I have an old but great running Westerbeke 30 and finding parts and competent people to do repairs to the bolt on stuff is getting harder and harder.....thank God my father owned a repair station and I have this knowledge to fix stuff in my blood but you can't fix it all

 

[RON20406]

I'd be interested in that name for future.....are they local to us?
I have an old but great running Westerbeke 30 and finding parts and competent people to do repairs to the bolt on stuff is getting harder and harder.....thank God my father owned a repair station and I have this knowledge to fix stuff in my blood but you can't fix it all

Rad, the company is Diesel Injection Service in Windsor, Wisconsin-- toll free number 800-735-7358. They also have a website that you can Google. This is an old Wisconsin company and you can mail your injectors/pumps for bench testing and analysis. They saved me quite a bit of money since a local Illinois company I had sent my injectors to destroyed them( I believe purposely) on inspection and then wanted to sell me new ones. This same Illinois company also said they rebuilt my injection pump and when I continued to have problems with it, I had it retested shortly after I reinstalled it and I was told they did nothing to the pump. They charged me $250. I believe DIJ will give you an honest evaluation if you don't have someone local. Goodluck and good sailing, Ron