3TNV80F Chinese Fuel Injectors?

[robertgalka]

Has anyone used these with success? They cost about 10% of OEM injectors. They are $70.00 US shipped from China.

I have this engine in an Exmark mower. It smokes bad and runs rough for about 10 seconds when you start it cold, and gives a little puff when it is started warm after sitting for a few minutes. It seems to me like the injectors are leaking fuel in to the combustion chamber. I've had it for 50 hours and it doesn't burn a drop of oil, and has lots of power. It doesn't smoke any other time either.

Also it was very difficult to start when it was cold as in 80 degrees F. I had to crank it for about five seconds. It starts perfect when it is warm. The glow plugs are automatic, so the computer doesn't tell them to come on until it is really cold. I hooked up a manual switch for the glow plugs and now it will start immediately when cold. I just have to use the glow plugs for a few seconds.

 

[thepumpguysc]

Post a picture of them or send it to my email.. I might be able to rebuild them cheaper..
My email is my screen name at aoldotcom in your mail server..

 

[thepumpguysc]

Never mind, I found them.
My 1st hand experiences have not been good..
I tell my customers not to get them, they’re junk.
I still have customers that get them and then send them to me to check them..
So far I’ve found metal in one and the opening pressures are ALL OVER THE PLACE.. I actually found one in a set of 3 that was 1000 psi low from the others and it goes the other way on another set.!!
I, in good conscious, can not endorse them.

 

[robertgalka]

I ordered a set for the heck of it. They were $70.00 US shipped. If they don't work I can always put the old ones back in. It looks like it is as simple as changing spark plugs on a gas engine. Bleeding the system might be the hardest part.

If it is possible to get them rebuilt it would be a Winter project. I didn't even know that an injector could be rebuilt.

It seems that smoking at start up is a common problem for this engine. Lots of the smaller John Deere tractors use this engine.

 

[thepumpguysc]

It’s not as simple as it looks.
U see that return line joining each injector.?
When u go to loosen that nut that’s holding it on, the line will spin on u and break..
I always use a HAND IMPACT TOOL & hammer to jar the nut loose.. that’s if I have room.
If not, I’ll put a wrench on the injector body and hold it while loosening the return nut..
Heed these warnings.

U need to find the tightening torque for the injectors in the head AND the return line nut..
The last thing you want is to get it all done (not torquing) and find an injector leaking compression and have to tear it all apart..
You’ll probably have to anyway, because the injectors are junk.. (lol)
Good luck

 

[robertgalka]

Do you think I am on the right track thinking it's the injectors? It doesn't use any oil, has lots of power, and the coolant level hasn't changed either.

It's not really a problem, just more of an annoyance. If I can fix it for a couple hundred dollars I will, but I don't want to spend over a grand on OEM injectors. I think I will try some injector cleaner first and see what happens.

 

[thepumpguysc]

Yes, I think you’re on the right track.. leaking injectors will create those symptoms.

If using anything in the tank, FOLLOW THE INSTRUCTIONS.!!
To much is not a good thing..
I’ve personally seen an inj pump eaten from the inside out.!!

 

[robertgalka]

Thanks, if I have any results I will update this post.

 

[freightboy]

Could be the injection timing as well.

 

[robertgalka]

I broke the line, otherwise everything went well. The engine smokes less and runs smoother when I start it cold. It used to smoke white for 5-10 seconds and run rough. Now just a puff of black smoke and it runs rough for a second or two. I only did one cold start so far and I used the glow plugs.

It rained here, so I can't cut any grass until tomorrow. We will see what it does under load.