YM336D - Started knocking loud while tilling

[90cummins]

If you didn't remove the nozzles make sure there are no machining particles hiding in the injector chambers.

 

[tcartwri]

What does concern me is the fact milling .011" from the head makes the pistons much closer to the head, even with the head gasket. Seeing as there are dents in the pistons where the injector nozzles have hit the pistons tops it appears the nozzles are a major concern, especially now.

Domush, You are going to have to source a thicker head gasket, or have one made from copper. You do not have enough running clearance now with your valves. Do not reassemble the motor with a factory head gasket.

 

[284 International]

According to an online calculator, milling the head 0.011" will take your compression ratio from 21:1 to 22.4:1. My 3 cylinder YM186 has a compression ratio of 23:1. While they are different engine families, by itself I don't think will damage anything to have a marginally higher compression ratio. Perhaps the injector pump timing would need to be retarded, but I really don't know. A service manual should address what to do after milling the head, but I have no knowledge of this.

 

[Car Doc]

I am not sure the gas engine calculator is accurate 284 in this instance since we dont know the actual cc of the chambers and the other pertinent info maybe you have all that dont know that either is why I say that?

I have my doubts it raised it a full point but I may well be wrong it may be raised even more but based on the specs needed I dont think we have enough data. jmho

My engine runs fine and I did the same exact mill if not a bit more I however added an extra copper seal under the pre-chambers like I mentioned and used stock gasket bla bla bla fwtw.

 

[Car Doc]

I hate having to remove those nozzles (never did remove them completely), but if that is what is needed, so be it. I was contemplating simply grinding a flat spot into the nozzles in order to make them flush with the head, as right now only one of the three sits below the head surface, and only about .005". That would not require much grinding. It seems every time i have to remove something else, something else breaks and requires another Hoye order.

Opinions on grinding the nozzle bottoms instead of shimming?

I have been scratching my head over the hesitation to knock the pre-chambers out Domush for a guy who can build pullers to remove liners this task seems like an ant hill to a mountain climber just saying...

Also once they are out (if you so decide the need) be very careful with the injectors there is s very sharp point on the end that is critical to the proper injection stream so knock the chambers out from the bottom with a deep socket over a bench is my advice so they dont damage the tips.

here is the Hoye link to whats under there fyi. (I cant cut and paste it why dont know?)

www.hoyetractor.com/DESIGNS/injector-parts.jpg

 

[California]

be very careful with the injectors there is s very sharp point on the end[/url]

??? do you mean the pre-chamber is pointed, the part he was talking about grinding down?

The injector itself is blunt on the end. Here is my photo that corresponds to that Hoye diagram.

FWIW - I haven't tried it but Aaron (Hoye) once commented it is very difficult to drive the chambers out after they have been in there many years, and this would be a project that is best left to a cylinder head shop. (or an experienced pro like Car Doc). I'm guessing this is because the injectors are mounted at an angle, requiring the head to be blocked at an angle before putting it in a press.

 

[clemsonfor]

??? do you mean the pre-chamber is pointed, the part he was talking about grinding down?

The injector itself is blunt on the end. Here is my photo that corresponds to that Hoye diagram.

FWIW - I haven't tried it but Aaron (Hoye) once commented it is very difficult to drive the chambers out after they have been in there many years, and this would be a project that is best left to a cylinder head shop. (or an experienced pro like Car Doc). I'm guessing this is because the injectors are mounted at an angle, requiring the head to be blocked at an angle before putting it in a press.

He said to whack them with a hammer and big socket, maybe they are tighter than that?

 

[winston1]

Hoye sells this tool, I believe they have it made or make it themselves. May be a little high for one time use but I doubt Hoye has much mark up on the item. Yanmar Tractor Parts: INJECTOR REMOVER KIT

 

[California]

That tool will pull out the injector, the component shown in my photo. The head doesn't need to be removed. This is similar to removing a spark plug (except a straight pull).

However the two 'chambers' below the injector (see Hoye's diagram) need to be driven out from below.

 

[winston1]

That tool will pull out the injector, the component shown in my photo. The head doesn't need to be removed. This is similar to removing a spark plug (except a straight pull).

However the two 'chambers' below the injector (see Hoye's diagram) need to be driven out from below.

Woops, my bad, I thought there tool pulled the whole works.

 

[Car Doc]

??? do you mean the pre-chamber is pointed, the part he was talking about grinding down?

The injector itself is blunt on the end. Here is my photo that corresponds to that Hoye diagram.

Mine had points on them right in the center the injectors did that is.

Spray oil is your friend as I said about 270 posts ago hahaha by now they would fall out on their own or just a bit of persuasion that and get the crud out from around them with a wire and air etc just my suggestion.

 

[Domush]

Well, I put it all back together and I could swear it blew another head gasket! I made a long video of it running. It sounds like it blew again somewhere around the 1 minute mark.

[ame=http://www.youtube.com/watch?v=OkYcMEP_n2Y]Tractor rebuild startup - Third time's the charm.. hopefully - YouTube[/ame]

I'm at a loss as to what more I can do. Unless the valves are not opening when they should, I don't see anything else which even could be wrong with it.

 

[dusty3030]

I make a motion that you name that tractor Job.

Good luck.

 

[Pete Judd]

Domush, think it may be to early to blame a head gasket. I always expect a new engine to smoke a little, until the rings set. I would look for bubbles in the radiator or foaming in the oil. You might have gotten a little bad fuel that caused it to smoke at 1 min. Watched the whole vid, and looked like you where running at about 12-1500 rpm for the most part. Sounds normal for a 3 cyl.

 

[winston1]

I too, watched the whole video and agree with Pete. Before the one minute mark you were getting smoke, at the one minute mark there was an extra puff and change in sound, but it quickly went back to how it was before the one minute mark. Never saw any movement in the overflow bottle. I know you have lots of fans rooting for you. :thumbsup:

 

[rmully]

Sounds like my ym2020 I think you fixed it! I would put some sea foam in it and get some good seat time just tooling around and put a few hours on it. I think the smoke may be from residual oil from the gasket replacement :thumbsup:

 

[5030]

Sounds perfectly normal for a naturally aspirated diesel engine and I too believe the puff at a minute or so was some oil or solvent in a combustion chamber being combusted.

I would run it unladen (no work, just the tractor itself) around for a couple hours and then pull the valve cover and check the valve lash and do an oil/filter change and then use it.

All naturally aspirated diesels smoke a bit, a nature of the engine.... Nothing to get concerned about and I really don't see the exhaust as oil smoking, just diesel smoke.....

 

[Domush]

As usual, you guys are right. I started it up today and drove it around for about fifteen minutes and it sounds nice and smooth. The exhaust has a nice low growl to it. It still smokes about half as much as before the rebuild, but the difference in engine sound is night and day. The hard knocking I heard yesterday is gone today and, for the first time ever, it reached a high enough temp for the thermostat to open. The engine and exhaust finally get hot, now. Before the rebuild I could lay my hand on the exhaust even when it was running! Now I don't dare touch it, as I can feel the heat coming off it.

Once it cools of for a few hours I'll check the head bolts again and check the valve clearances. I'm cautiously optimistic, but I think I might be okay!

As always, thank you all for your advice, encouragement and kind words. You make a tractor rebuild just another day on the farm

 

[5030]

Smoke is a good thing. No smoke, no fire. No fire no power.

Just keep a check on the dipstick and it will use a bit until the rings seat in and some thereafter, Anyone who says their engine don't use any oil is FOS. They all do

Some engines are particular about oil level as well, Caterpillar in particular. Fill a Cat to the full mark and a few hours later, it's down a couple quarts.

With a diesel, if it don't rattle a bit, something is wrong, but I'd still check the overhead after a few hours. Far as headbolts are concerned, we never check those after a rebuild. We progressive torque to factory specification and leave them alone. Remember, when you torque head bolts, you stretch them a tiny bit so we never retorque.

Go run it around your place for a while, change the oil and filter and go back to what you were doing when it puked. Just don't flog it. Remember all the sweat you put into it.

 

[Cub 7274]

sounded good to me to & your dog looked happy