Farmpro /Jinma 2420 injector pump timing question??

[thetester]

Hey guys, I just bought a farm pro 2420. It had a slight "what I think" to be a fuel knock. I noticed it was missing a stud on the rear injector. So I cleaned removed and cleaned the injector and replaced the missing stud. This cured 80% of the knock!

The guy I bought it from did say the injector pump was just replaced. To be honest he was pretty mechanically stupid and I've fixed several things no sooner than I got it off the trailer.

I still have a touch of white smoke at idle. When I throttle up fast it puffs a good bit of white smoke. I feel that maybe the injector pump is a touch out of time. I can detect a ever so slight knock but it's so faint I have to try and find it over the normal diesel noise.

Can anyone explain to me how to fine tune the pump on these tractors??

I see a bolt on the top (pivot) and one on the bottom that's ovaled (adjusting) I presume???

 

[piper184]

Does the white smoke go away after the engine RPM catches up with your throttle increase? If so, it sounds kind of normal to me.
Does it smoke more when cold and less when warm? This too is normal.
How is your thermostat? The one in my tractor failed by opening too soon and thus the engine never warmed up properly. Also the factory thermostat was too cold anyway. Once I replaced it with a 195° thermostat the engine ran a whole lot better.
White smoke at idle and when cold is normal but white smoke under power could indicate a coolant leak into the combustion chamber.
When smoking at idle (and warm) can you detect a raw fuel smell or a "rich" smell in the exhaust? If so, the injection pump may have retarded timing.
What engine do you have?
Have you tried changing fuel brand/grade? How about the filters? Does it run well at full throttle and have enough power?
I would think you could adjust the timing by rotating the IP but I would do that as a last resort and only after making good index marks to make sure it can be put back. Go slowly and by small amounts.

 

[thetester]

Thanks for the reply!! When it's cold it takes a bit for it to start. It will chug chug chug then finally pick up. At idle it smokes a little. When I add throttle it puffs a decent amount of white smoke then goes back to a light puffing. It smells like unburnt diesel and is irritating to the nose and eyes.

As it warms up it pretty much stays the same. The tractor is new to me so I couldn't say about any loss of power. It's a little Chinese farm pro or jinma 2420 with a ty290 engine.

At first I started to worry because of the knock. Then the injector cleaning fixed the majority. Now I've started checking and paying close attention to blowby. It's definitely puffing out of the valvecover but for the life of me after several videos, I just can't decide if it seems excessive or if it's reasonable.

The only thing left to try is pop testing the injectors, compression testing the cylinders, and finally moving or adjusting the pump!

I took another close look at the pump and man are these bolts going to be hard to loosen. Likely have to remove items to get to it.

Thank you for confirming some of my thoughts and giving me more to think about and consider!

I hope I'm not looking at a complete rebuild.

 

[piper184]

I have a Jinma 284 with the three cylinder engine so my manuals are not exact for your tractor but they should be similar.
Do you know how many hours are on the engine?
There is a procedure to re-torque the head after break in, do you know if that has been done? Never hurts to do it again.
On the 3cyl the crankcase is vented but the valve cover is sealed, is there a vent on your valve cover? I am guessing probably the oil fill cap has the vent?
Some blow by is normal without an PVC system it may seem excessive when we are used to closed and clean car engines. You have to think back to the 50's and 60's to remember what engines ran like for comparison.
What kind of oil are you using and when was it changed last?
Was the replaced IP remanufactured or new? In either case it could be the problem if it is not set up properly. I have watched mechanics repair and test pumps and injectors but have no experience doing any of that.
Do the instruments seem to be working? These tractors are notorious for having less than top quality electrical systems and even when they work they are not very accurate. If you have any doubts you can install a mechanical oil pressure gauge and use an IR thermometer on the thermostat housing to verify.
Diesels really need to get the coolant up to at least 195° before they begin to operate properly so that would be my first concern given the symptoms you have described.
Low compression and IP timing are next on the list.
If you have access to an Oxy-Ac torch you might consider buying some low cost wrenches and modifying them to reach the nuts that hold the IP pump on.
Having an oil and coolant analysis done might help determine if there is a head/gasket problem. In my area Caterpillar dealers sell sample bottles that you just mail in for testing. You can purchase them over the phone and have them mailed to you.

 

[thetester]

Thanks piper! This tractor "shows" to be a sub 400 hour tractor. Now I don't buy that after looking it over.

The original owner claimed he bought it at 12 hours. He used it some and let it sit. When he came back to it, he had issues and replaced a fuel injector and then the pump. Both wee brand new.

It's confusing really! The turf tires appear new. The paint looks mehhh pretty rough. The wiring is a nightmare. Having to trace down open circuits that turn out to be conne too s thstneed cleaned and put back.

The engine is pretty cruddy and gunked up to be a sub 400 hour tractor.

He said the brakes have been replaced. The srarter was replaced. I mean... on a 400 hour tractor???

Anyway there is tube coming off the valve cover to the intake. A blowby "vent" tube. Not sure if it's what your asking??

The oil was just changed before I purchased it. It was still honey colored.

I thank you for giving me all this input! I have read in the manual about the head retorque. I would bet it hasn't been done!

I'm just trying to decide what order of operation to go about figuring it out. I think I'm going to pop test the injectors. While I'm at it pull a compression test. If good move to the IP.

I feel this thing has set up for a long time. I'm thinking of adding some seafoam?? Maybe a lot of carbon on the rings. I'd wager that IP is out of time also!

Before I go into fuel and oil analysis I will do the routine checks such as compression, timing. If those fail or give me pause and all else fails to figure it out I'll just rebuild it.

 

[piper184]

Yes indeed the wiring is a nightmare. Poor quality and undersized wires. Connectors of low quality that break from vibration. Fortunately wiring is simple and easy to repair.
Do you know what year the tractor is? Sunshine is not your friend and a good tractor will look like junk after a couple of years sitting outside.
I didn't get around to the head re-torque until about 500 hours. It was fine and that may have been an issue for older tractors that was solved in the mid 2000's.
I miss-spoke about the valve cover vent. My tractor has the same set up as yours, a hose that goes from the oil cap to the intake. This provides PCV function without the valve. There is a breather on the right side of the block near the back that has a small canister on top of it. Inside is a metal filter material and it self drains back to the crankcase. I looked at the filter after about 700 hours it had oil in it but was not dirty. There is a little trace of oil in the valve cover hose and inside the intake. I wiped it out with a rag and it was good.
I have tried to keep up with loose bolts, seeping gaskets and hosing off the engine at least once a year to keep the gunk buildup to a minimum.
Sounds like some of the history was not disclosed. Reminds me of the "ran when parked" auction tractors.
Have you tried listening to the cylinders with a mechanics stethoscope or screwdriver? If you can hear a difference, swap the injectors and check again. That would at least eliminate them from the puzzle.
A fuel additive for injector cleaning couldn't hurt. Might have to run a tank of fuel for it to have any noticeable effect.
Sounds like you are on the right track. Popping the head off to have a look-see down the holes should be easy enough.
Keep us updated on what you find.

 

[Bob Rooks]

My tractor has the same set up as yours, a hose that goes from the oil cap to the intake. This provides PCV function without the valve.

Just a FYI in case. Where the hose attaches to the intake manifold, it is a threaded slug with a small orifice. This serves two other purposes besides evacuating the crank case (fresh air is drawn in through the wire gauze breather that should be kept very clean)- It prevents any oil that gets by the baffle in the valve cover from getting into the engine in sufficient quantities to fuel the engine; Also the same purpose for crank case vapors and causing a runaway.