766 engine oil useage

1370rod · Mar 12, 2012

freshly overhauled with a engine kit from Howards this engine started using a little oil. Got around 30 hrs and it would go through a qu. in 6 hrs. Ran 6 mo. with no improvements. Howards was good to us and gave us a replacement set of sleeves and pistons. We installed them and had no oil useage for 20 hrs. but now its back to its qu. every 6 hrs. or so. JD break-in oil was used from the start and tractor was broke-in for 5 hrs. on dyno at varying loads. Starts good and has 100 hp. When the first set of sleeves where removed about half of them had up and down scratches like they had injested something abrasive. To us it appeared as though small balls or particles of carbon had formed above the top ring and where the cause of the scuffing. Everything was inspected and no sign or trace of outsde contamination could be found. We have not pulled the engine down again yet, but I bet the same thing reoccured. The engine was stuck when we purchased the tractor so we have no history of past problems. Any thoughts welcome,we don't want to do this again, thanks, Rod.

pete 23 · Mar 12, 2012

Is this the 360 engine. There were problems with the fit of the sleeve into the block on these engines. Some of it was the top o-ring groove not machined properly and needed a bevel on the bottom side of the groove. Other problems was insufficient clearance in the lower portion of the block. That sleeve has to fit with some clearance without the o-rings on it. In other words the sleeve has to drop right in and be able to easily turn it . Another thing, those Red Power pistons may not have enough piston to sleeve clearance. Go for the high end of the specs.

the tractor vet · Mar 13, 2012

Like Pete said and i will ad to this . a 766 setting at a 100 Hp is a bit over fueled and being over fueled can cause washing of the walls and fuel not burning can turn to more carbon . Also along with fitting sleeves to block it is wise to FIT PISTONS TO SLEEVES today. One other thing about breaking in a diesel engine is HEAT , if the engine is not getting up to and above 165 degrees and better if it is running 185-195 range the fuel in not getting burnt properly . Making sure that the injectors are all working good also plays in how well your rebuild is going to play out. As for break in OIL myself i have never played into that . I run what is going to be run in that engine . And a better way for break in is TO RUN IT , Now not sayen to take it out and put her on the plow and plow 500 acres non stop but Chore work , haling manure moving bales spreading fertilizer grinding a load of feed if you can load the grinder evenly . And the big thing set it back to being real close to stock or 10% above atleast for the first fifty hours . And make sure that engine temp is at operating temp.

pete 23 · Mar 13, 2012

To be honest, I never ever noticed the 100 hp part. If it truly develops l00 horsepower while running at rated engine speed you are pushing it too hard if actually using that horsepower. Too dam hot inside those cylinders. I'm with using same oil during break in as you intend to use after. A newly overhauled engine needs maximum protection during that period and a break in oil may not have that. Remember the days it was popular to use non detergent for break in. Well, that is called wear in, not break in. I worked at John Deere for a while and they did indeed use break in oil. I did what I was told, not what I felt. One more thing on those sleeves, besides checking piston to sleeve clearance, there have been ring sets showing up with too little end gap. I know one engine that siezed first time it was worked hard (John Deere). They determined too little end gap. I also found one ring in a set that had near zero end gap.

cd1 · Mar 13, 2012

Check out the instructions on your piston rings as to whether or not you should be putting oil on them on assembly. Some are not supposed to be oiled now days.

1370rod · Mar 13, 2012

I was not aware these tractors where rated at 80 HP so yes it does have 100 hp, we will set that back. The fuel pump is also a fresh Reman along with the inj. they have new tips. IH parts book calls for a 190 thermostat, we installed a new one.As for the break-in oil Howards strongly suggests its use. I sure thank all you guys for the helpful info. Rod.

the tractor vet · Mar 13, 2012

I have bought lots of stuff from Howards and i can tell ya this , Best put the Mic.'s to each and every part and FIT each piston to each hole as well as ring end gap as Pete has said. And as for oil in that engine IMHO the only oil should be I H #1 30 weight from start till finish . It only takes a little while longer to make things fit the first time and get the job done wright . When i am doing and engine job it is on the customer's dime and if i mess up then it is on my dime . If ya want a 100 Hp. tractor then get a 966 . I do not have a problem with adding 10% to and engine but really do not like going much higher.

charlieu · Mar 14, 2012

As I read through your problem and look at all the replys one item comes to mine. Did you replace the air cleaner filters? There are times that we all have to step back and look at a problem from outside the box. Good luck as you redo your engine again. charlie

766 engine oil useage

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1370rod

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pete 23

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the tractor vet

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pete 23

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cd1

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1370rod

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the tractor vet

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charlieu

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