New Engine break in

[cannarella]

I finally got the new engine replaced in our L4310 HST. After getting everything hooked up, fluids filled, wires connected, and all double checked I fired her up for the first time. She purred like a kitten after getting the fuel bled. My question is about engine break in. The grate motor didn't come with and instructions so I was wondering what Kubota recommends on engine break in procedure. I am really looking on if they want on engine speed variations and such. I know to change the oil after 50hrs according to the maintenance list.

Thanks
Andy

 

[gwdixon]

Lots of information on this subject if you do a search for it. Lots of reading.

 

[TripleR]

As mentioned, there are all kinds of threads on this. Kubota recommends letting it warm up good, not operating at full RPM for the first twenty hours I think and to vary engine speeds. You should be able to do all you need without any problems. I am breaking in an M8540 right now and I stop every once in a while and let it cool down, run it up and down on the RPM scale and of course let the turbo cool down before shutting it off.

 

[cannarella]

Thanks, I wish I had a turbo... Just one on the car.

 

[dex3361]

What happened to the original engine?

 

[kuboman]

Biggest killer of new engines is excessive idling. Let her warm up and cool down but maker her work enough that the combustion temps and pressures are up there. Vary load and speed for a few hours and then work her.
:thumbsup:

 

[cannarella]

Randall, it spun a connecting rod and punched a hole in the side of the block. Long story. Basically one of the oil plugs vibrated out and the engine lost all the oil. Tractor was sitting for a while and we topped off fluids before running its. When the oil light came on it was immediately shutdown. Plug was found and oil was refilled. Ran fine for 30 minutes and then it blew. We were given the tractor knowing that we had to replace the engine.

Thanks Kuboman that seems to be the general consensus. I have to split it Friday to put in the clips that hold the clutch fork to the throwout bearing. They weren't there when we replaced the clutch. sigh. Better do it now then wait...

Andy

 

[dex3361]

That would be such a bad day. I am glad it was a refurb freebie for you.

 

[cannarella]

Well we paid for a new engine but got the tractor for free. So in the end with engine, fluids, filters, orings, ect. it cost us $6000. Oh I didn't mention it belongs to our church and we have a lot to bush hog. We have been borrowing a tractor for a long time and this it such a relief that we don't have to worry about breaking someone elses...

 

[funwithahoe]

As mentioned, there are all kinds of threads on this. Kubota recommends letting it warm up good, not operating at full RPM for the first twenty hours I think and to vary engine speeds. You should be able to do all you need without any problems. I am breaking in an M8540 right now and I stop every once in a while and let it cool down, run it up and down on the RPM scale and of course let the turbo cool down before shutting it off.

Always wondered - Why does the varying of RPM's matter? I respect triple R and am not saying that it doesn't but kinda wondered why it would make a difference??

 

[Skyco]

Undesireable wear patterns can develop in an engine broken in at one speed, hence the varying speed advisory.

 

[PHILIP8N]

Undesireable wear patterns can develop in an engine broken in at one speed, hence the varying speed advisory.

I break my engines in at varying speed and loads if possible, I think it is good practice. This recommendation goes back a long way. I also like to have as many 'heat soaks' as possible. Run engine to operating temp, cool down, do it over and over. I also like to short change my first oil and filter. On my Kubota I changed oil and filter at the 20 hour meter mark (switched to 5w-40), then at the 50 hour meter mark (30 hour oci). However, I have worked on hundreds of single speed generators and compressors (50 bhp to 800 bhp) and never seen a problem with break in. Philip.

 

[TripleR]

What Skyco said. A lot goes into it, but essentially that's it.

Now a real mechanic will tell you the ins and outs and even among them there is debate on running WFO on a new engine to seat the rings. My brothers are mechanics as was my grand father, but that gene skipped over me.

 

[Skyco]

Its funny all the disagreement amongst motorheads about break in...I saw a video once of the 7.3L Powerstroke diesels being tested in the factory...basically they run the heck out of it for a few minutes on a dyno, so much for a gentle break in....Must work, mine has over 180,000 on it and doesn't use any oil.

I do find it interesting all the shiny stuff in the first oil change on a new motor...I always do the first oc real early. I've seen an astounding amount of stuff come out the first oil change on some chinese engines, but so far my 2 chinese cloned Yanmars have held up. Then you get the Honda guys who claim there is some mystical ingredient in the original oil and changing it early will screw it up, hasn't happened to any of several Hondas I've had, they get the early change too.

 

[funwithahoe]

Its funny all the disagreement amongst motorheads about break in...I saw a video once of the 7.3L Powerstroke diesels being tested in the factory...basically they run the heck out of it for a few minutes on a dyno, so much for a gentle break in....Must work, mine has over 180,000 on it and doesn't use any oil.

I do find it interesting all the shiny stuff in the first oil change on a new motor...I always do the first oc real early. I've seen an astounding amount of stuff come out the first oil change on some chinese engines, but so far my 2 chinese cloned Yanmars have held up. Then you get the Honda guys who claim there is some mystical ingredient in the original oil and changing it early will screw it up, hasn't happened to any of several Hondas I've had, they get the early change too.

I agree - just treat it right and it will be fine!!

 

[cannarella]

So can I hog with it for break in? What defines full throttle? I am assuming anything over PTO RPM.

 

[kuboman]

Really varying the rpm came in with the automobile and is not really applicable with tractors. Varying the load is far more important than the speed. Keep the speed high enough that you are not lugging and run it.

 

[PHILIP8N]

So can I hog with it for break in? What defines full throttle? I am assuming anything over PTO RPM.

My goal is to break in every new engine I get and collect and perform a used oil analysis on the way to figure maximum oil change intervals. Unfortunately, I did not get to properly break in my new Kubota engine. I drove it 3 miles from the dealership to home at full enigne rpm, then spent the next 2 days bushogging 18 acres of 6' tall weeds. Change oil and filter and collected oil for uoa at 20 hour mark and at 50 hour mark. Now at 70 hours, no consumption or problems. Philip.

 

[dex3361]

So can I hog with it for break in? What defines full throttle? I am assuming anything over PTO RPM.

I would run a Brush Hog and not worry about it. Just vary the RPM and load a bit. You can do that while cutting by changing your speed and it will vary a bit anyway. The Rpm I would keep at 1500 to 2000.

 

[DiezNutz]

Really varying the rpm came in with the automobile and is not really applicable with tractors. Varying the load is far more important than the speed. Keep the speed high enough that you are not lugging and run it.

It is still beneficial to vary the rpms to alter the wear patterns, but I agree that the load is the most important thing. They aren't always mutually exclusive. Load = increased combustion pressure = rings seating, as opposed to just filing themselves away on the cylinder honing which leads to bigger ring gaps and lost compression.

I always go easy on new engines during warmup, then once it's warmed up, I work it good. You can load it without using full rpms (thereby obeying the manual), you just don't want to lug it. Lugging = too much load at too low an rpm = bad.

Diesels take a long time to completely break in, and the worst thing you can do for the rings is baby it all the time.