Detroit Desiel 353 Issues

Well im having issues with the engine on my Gama Goat. Im a pretty crappy diesel mechanic and could use some advice.

-The engine is very hard to start in any weather but cranks fine after its been run for the rest of the day.

-When you first start it you get allot of white smoke that dissapates after it warms up. When your driving it the engine has allot of black smoke when it is strained. LOTS...

-Its had some bad diesel in it before when it sat for a few years and the injectors may be clogged or dirty but im not sure.

-Top speed is slower than it should be but it has pleanty of low end power.

I think Im having a fuel problem and have dirty injectors or something related but im not knowledgable enough about diesels to be sure. Im not sure what the symptoms the engine is telling me may mean and i dont want to rebuild the whole engine if i dont have to.

any help would be appreciated......

David,
It does sound like fuel problems, white smoke indicates fuel too lean, could be clogged filters, or dirty injectors, or the injectors out of adjustment,( they need to be set like tappets," running the rack"). Get a hold of a shop manual for the Detroit 53 series, they are actually pretty easy to work on, when you have the specs to refer to.

I am no expert on detroits but do have a little experience. I have an antique John Deere 435 with a 253 detroit. They were hard to start when new and usually required a little ether to get them going. Once warm they would restart OK. I have been told that smaller valves in the older engines caused that. Newer Detroits have bigger valves and that eliminated the starting problem. White smoke I think is normal when cold as combustion is not going on very well. The fuel system is unique on these engines and special tools are required to set the racks. Each cylinder has its own pump and each one has to be set. Do it wrong and you could have a runaway engine on your hands. That is why they have emergincy shut down systems that shuts off the air supply in case of runaway. I think you need to have a Detroit mechanic adjust the fuel system first and see if that cures the problem. Also Detroits were not intended to idle and be babyed. They are supposed to scream all day long. They are also known to be great oil leakers.

Dave,
Your Goat sounds pretty normal in that it smokes lite when cold and clears up when warm. I think your right about dirty injectors. The 353 is a great little engine and the 2 stroke gives great and smooth torque output. But they are real sensitive to dirty fuel. Check the filters first, if they are clean, take out most of the fuel from both tanks and add a full bottle of "Sea Foam" into one of the fuel tanks and run the @#@$$ out of it. This stuff will definitly clean the injectors. Then put good, clean fuel back in with a fuel additive recomended by Detroit.
I've had my Goat for 19 years and drove it to Kansas City in 2000 to the Nat Convention. I've have had issues like this too. Since using the "Sea Foam" problems solved. If this doesn't help, then see a good Detroit mechanic. Take a fat wallet with ya.

Pull off the valve cover and look at the little disc on the injector heads. There will be a letter and number there. The older series injectors like the "S" series had low pop pressure, causing hard cold starting and smoke. Try to go to "N" series injectors, which pop at a much higher pressure, atomizing the fuel better for better starting and less white smoke. N40 to N50 would give you good power. A discussion with the Detroit Diesel shop or injection shop of your choice would help for sizing. Detroit has an injector exchange program for about $55 per injector with your old ones as cores. For that cost, on a Detroit, you have basically rebuilt the injection system. No costly injection pump to mess with! You can also take off the exhaust manifold and check for carbon fouling in the ports. We have a 6v53, which is basically two 353's in a v configuration, that had very badly fouled ports, bad enough to limit top speed.
Once you really understand these engines, you will see what quality they are. The legendary oil leaking simply does not exist if they are built right. The heads sit right on the block; no head gaskets in the normal sense. They have steel fire rings at each cylinder and o-rings at oil and water passages. Let's see that blow a head gasket!! Heat transfer is no problem. Find another make engine where the manual tells you exactly what cracks you can have in the crank and put it back in service! In general a very high quality engine, but VERY badly misunderstood. Get the rack settings right, and it will make you happy.
Regards Marti

thanks im greatly appreciative for the info. The fuel and injector issues are explained here a bit better than anywhere else ive found.....

thank you all!!!!!!!!

In reference to the gentleman with the John Deere with a 2-53, your hard starting problems are not caused by the exhaust valves as there was only one size. However there were early engines built with 2 larger valves and later engines with 4 smaller valves which gave better performance. However valve size has NO bearing on starting, just like some people saying that a turbo causes hard starting because of restriction. The 6V53 I have had the ports 80% blocked with carbon when I got it and would start fine, just not run out well. any engine requires more flow at higher speeds not lower speeds, You could start a 4 valve Detroit on only one valve just fine. starting in a diesel engine requires enough heat from compression, timing advance, fuel quantity,and proper atomization as well as sufficient air, A gas engine starts with a "closed" choke and throttle, but wont run out that way! In Detroits especially, the injector type and timing are the factors governing starting, Older engines had 600 psi injectors, later engines generally use 2800 psi on multi-hole tips, "S" series and "H" series are some examples of low pressure injectors "N" and "M" series are 2800 psi and will start and run MUCH better, most turbocharged diesels Detroits as well, have retarded timing, lower compression, and may have less aggressive cams some also have a device that limits fuel at low speeds to reduce smoking, all VERY bad for starting! P.S. I always liked those tractors!

so if i change my older type S injectors to the newer type N injector are any other changes required to make it work?

Dave, have you looked at your injectors?
Mine is a 72 and has N type already. Take a look.

i will as soon as im home, im stuck in iraq working again but will be home again in a month. Now that i at least have a place to start it should be a fairly easy fix.

No other changes are necessary. Just be sure the fuel system is clean, and also be sure the copper tubes the injectors fit into are clean where the bottom tapered end of the injector fits. There can be carbon there that needs cleaned out before putting in a new injector. When you are ready to replace them, you can contact me for info on the settings. No special tool needed, just a set of dial or digital calipers. If you already have N series, get them tested to see if they are working right.
Regards Marti

thanks marti,

ill be in touch pretty soon. im back stateside on the 7th so ill probably be greasy within that first week. The wife and kids come first but my toys are following closely behind.....

thanks.

well as an update to any who may be reading this on through a search I used the Seafoam and it cleared up everything. Other than changing the fuel filters afterwards i had no problems. Starts on the second hit of the button usually, still smokes and uses so much oil i wonder where it all goes but all is well.

SEAFOAM IS GREAT, PUT IT IN EVERYTHING DIESEL YOU OWN!!!!!!!!!!!!!

Thanks to all who helped, feel free to drop by the house for free beer and to help me replace some wheel cylinders.....lol

Dave,
That stuff works in any combustion engine. It really cleans carbon out of small gas engines. Pour a little in the carb while running and standby for a smoke screen. The carbon will come out in chunks. Put it in the gas and it will clean valves and carb.
Sounds like a commercial doesn't it. Just not often do you find something that does what it's advertised to do.
Glad it's running.