Rebuit engine breakin

This summer when i get done rebuilding the jd 50 engine, what are some good methods to use to break it in?

Use break in oil and put it to work.

Drive it like you stole it .
What is your definition of a rebuild ?

Not much you need to do any different from normal operation.

The main thing is to be extra observant of the gauges, coolant and oil level, leaks, noises.

Be sure to retorque the head and set the valve clearance after the first start up.

(quoted from post at 10:35:14 02/28/23)

Be sure to retorque the head after the first start up.

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I am not buying the need to re torque head bolts. When you bought a new 2 cylinder in 1955 were you required to take it back to the dealer for re torque? New cars and trucks have never required a re torque AFAIK. They get bolted together at the factory and many run for hundreds of thousands of miles without being touched. Someone enlighten me.

I suspect they were retorqued at the factory. It's a one time thing, once the engine is initially started
and brought up to temperature.

The older engines commonly used thick copper sandwich type gaskets that were intended to be reused with
sealer. Due to the thickness, they also tended to compress and relax as the inner composition compressed
and the sealer squeezed out. They also promoted warpage, especially with flat head engines.

As machining quality improved, some automotive engines went with steel shim type gaskets, they did not
need a retorque. But they only worked well for the first assembly when everything was new, clean and
freshly machined.

There are many factory shop manuals that do require a specific retorque procedure, especially diesels.

Quote:
I am not buying the need to re torque head bolts. When you bought a new 2 cylinder in 1955 were you required to take it back to the dealer for re torque? New cars and trucks have never required a re torque AFAIK. They get bolted together at the factory and many run for hundreds of thousands of miles without being touched. Someone enlighten me.


Many components are no longer designed,constructed,and or supplied by the original manufacturers engineered specification.
Now quality control is often less than stellar.

I have first hand experience on the after math of a John Deere 70 Diesel Head gasket replacement.
The above particular Tractor had a head replaced.The owner never re-torqued the head after the coolant was up to 175 Deg F. He wasted TWO head gaskets.
Yes, I assisted him and the head was NOT requiring any machining,and the same with the matting surface of the engine block.
We located and installed a head gasket,placed the John Deere on our Sawmill....after 10>15 minutes of running time after the engine coolant reached 175F the HEAD was re-torqued.

For those of you who do not re-torque the heads,that's OK, as you own the equipment...it's you $$$'s

For those of us who do own the equipment and re-torque that OK,as we own the equipment...it's our $$$'s

For those of you who do not re-torque the heads,that's OK, as I receive your $$$'s to re-torque the heads.

Bob..Owner operator John Deere Styled D's...520...and have since sold off my R's...

Ah with some engines even after put in service they need a retorque . D 361-407 needs this done AFTER the first 50 Hours , NOT many know that with your prized 5.9 Cummins after 10-15000 miles they needed to go back in for what is called put in service where they run the valves check pump timing and delivery and OH wait check head bolt torque . People bought them and just RUN the bag off of them . When i got my Cummins since i was NOT and expert on them YET in that size i went to the Cummins dealer in my area and had a long talk with and OLD friend about the 5.9's and bobby checked to see if mine had been put in service and it had NOT . So i asked Boby on How much to have this done and he said WHY you know how to work on Cummins not much difference just need the tool kit for the 5.9 . And so i bought the TOOL kit for 1200 and change and when i got into mine with 62 K on the clock i found that the valves were WAY out of adjustment ya could have throwen a cat between the rocker arm and valve stem . and yes i pulled the head and got a wee bit on each and as for what the valve adjustment did was OH about 4-5 MORE MGP and wow it ran a lot better.

I will chime in....
Elders near me, overhaul a 1755 diesel, when getting back, from shop, they hook this to a smaller tractor and drive them both in gear, he didn't have a disc or plow to work it, was too muddy.
After a spell they checked fluids, temperature and then retorque the head gasket, warm it again and run the overhead, valves.
Runs awesome.... GG Wes

New engines also use torque-to-yield head
bolts and multi-layer stainless steel or
coated steel, one time use head gaskets.
The head gaskets crush when the bolts are
torqued. The head bolts stretch to
maintain clamping pressure through heating
and cooling cycles.

Deere is one that calls for getting it hot. This has been the
case for a good long while although on the newest tractors Im
unsure. I always kinda figured it was to cover their rear end
more than anything. Caterpillar has the same style fire ring
gaskets and nothing is ever said about a retorque. I have
seen relaxation from the gasket crush on a 4020 though even
without starting just sitting over the weekend however so I do
retorque. On new generation or later I purchase an OEM
gasket Ive been warned by my usual engine parts supplier
that its not worth trying others.
A 2 cylinder is a different breed of gasket. Thin all metal with
lead crush washer. Do like the old timers did with their silver
paint and go get a can of copper coat or your favorite like
product. I had to go to the styled manual to get a torque spec
for my 1938 b. The unstyled manual just said torque to snug.
Those must have been the days...

(quoted from post at 07:58:42 03/01/23)
A 2 cylinder is a different breed of gasket. Thin all metal with
lead crush washer.

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I just got a 730 Diesel gasket set from a well known Deere vendor and the head gasket is some sort of multi layer sandwich.

Good day Scott 730
Quote:
just got a 730 Diesel gasket set from a well known Deere vendor and the head gasket is some sort of multi layer sandwich.

After you have the above HEAD GASKET installed,Engine up to say 175>185 Deg F, and make the 730 do say 8 hours work,please get back to us on YTafter about 20 hours work.
Interested in the out come of a multi layer sandwich HEAD GASKET that is not re-torqued.
Thanks
Bob..