anyone know much about 3116 cats?

[oilerman]

Hi there... just wondering if anyone knows a thing or two about 3116 cat motors. I have one in my topkick gravel truck that is stumping me. It runs fine when first started and cold... but once you warm it up and get it to pull harder it will start chattering shaking and losing power and blow jet black smoke out the pipe. I have been told head gasket but there is no antifreeze in oil or vise versa... no pressure in the radiator... I been told turbo and it seems fine.. tight no oil leaks..What else could it be?

Here is a video of it running.

http://www.youtube.com/watch?v=A6E4g9VSFPI&feature=youtu.be

 

[lantraxco]

Sounds like fuel knock to me, I'd start with pulling the injectors and having them checked, then go from there. Might also be a timing issue, but as I said I'd start with getting the injectors tested.

:my2c

 

[Mike L]

don't know anything about 3116s but black smoke is an indication of unburnt fuel. sounds like you have an overfueling problem.

 

[oilerman]

Yea... this truck would smoke like that out the pipe when I bought it.. but it ran ok then...it would just smoke under hard exceleration. I thought maybe 3116s were like that. I have another truck with a 3126 in it and it doesnt smoke at all like that and runs way smoother.... I like the 3126 better.

 

[Delmer]

I'd listen to Lantraxco.

I have a 3316 and it doesn't sound or smoke anything like that, sounds smoother than any VW TDI I've seen.

 

[BillG]

I have seen 3116's blow black coal smoke when the O rings on the injectors start leaking. Pulling the injectors is good advice and make sure to use the latest O rings, they were updated a couple times. Also, special tools are required to set and adjust them.

 

[oilerman]

And thanks landtraxco for the advice.

 

[oilerman]

hmm ok.. I will ask around to see who can pull them out for me. In the video the engine is running sorta ok... you can tell it doesnt want to idle correctly... but with a load it will all of a sudden start to chatter and shake and blow pure black smoke all the time and only get about 800 rpms until you shut it off and leave it for awhile...

 

[partsandservice]

I agree with those above that it sounds like a fuel knock. You can check the injectors individually by removing rocker box cover and activating the fuel rod on each injector to see which on is dead. Sounds like one of the injector fuel rod is sticking. Also the rack will require resetting if you remove one or all injectors to run its best. Number one injector has to be set and all others synced to it. I am assuming you have addressed a charge air leak or blockage.

 

[Dad5]

The 3116 has brass injector sleeves. sometimes they will leak in the area of the injector seat in the sleeve. Sometimes a sight glass in the return line will show compression bubbles if the seats are leaking. If the injectors are removed you must cut the seats before renistalling them. If the seats have been cut too many times already they must be replaced. Cat has updated the tooling to include an injector seating tool. This helps give a better seal between the injector and the sleeve. Do not attempt to hold down the injector rocker like you would on a 2 stroke detroit as the push rods aren't captured and will go flying if the tension is removed. There is quite a bit of special tooling required to time and synchronize the injectors after reinstallation. They require a delicate touch and a steady hand to make them run well. A torque wrench is important as the fasteners are small and can be overtoqued easily. It is good advice to leave the governor alone as a special test bench is required to run/set them on. If needed Cat sells reman governors. Also the rack that runs the injectors can sometimes bind. It has brass bearings and if it isn't mounted properly can lead to many starting/driveability complaints.

 

[Pipelinemech]

Dad5 is correct. i have a customer that runs a handful of D6m's with the 3116. they will have the same symptoms under load. put a clear piece of hose in the return line and lug it down and the fuel turns to foam. cat has an updated injector cup in stainless now for these. i have a few of the overhead and injector setting tool groups for these motors. if you want one let me know.
Justin

 

[oilerman]

Hmm maybe I will check out the return line. Where is it located? One other thing I forgot to mention... I dont know for sure if it would have any bearing on this problem but The fuel tank is pressureizing to the point where it will blow the fuel out the vent line??? Now I just leave the cap loose so air can escape?

 

[PAcattech]

If it's putting that much pressure back into tank Injector cup or cups are bad and as others here have said you cant do much of anything with them unless you have special tooling to install them and set them up.

 

[lantraxco]

Hmm maybe I will check out the return line. Where is it located? One other thing I forgot to mention... I dont know for sure if it would have any bearing on this problem but The fuel tank is pressureizing to the point where it will blow the fuel out the vent line??? Now I just leave the cap loose so air can escape?

not criticizing at all so don't take this wrong, but that's kind of the clue that clinches the diagnosis :yup

 

[oilerman]

How much do you think a motor swap would be? Am having a hard time finding a mechanic that works on these that is nearby.

 

[big ben]

Don't know how much a motor swap would be but I can guarantee it will be cheaper to get a Finning (Cat dealer) mechanic there to at least troubleshoot it and cut the sleeves and reseal injectors as required. Alberta isn't that big - a Finning branch or resident mechanic must be within a few hrs ????

 

[powerjoke]

Can they do a power balance off a laptop ? Or you could always use a infrared temp gun on exhaust manifold

 

[oilerman]

the closest is Grande Prairie... 2 hrs away.... I guess I will have to bite the bullet and do that.

 

[Randy88]

If I liked the truck, I'd repower it with a cummins, if not I'd either trade it off or haul it to auction and go buy something with a cummins already in it, but that's just me and my opinion of those cat engines, just my two cents worth.