Builds 1985 JDM 3B Engine Rebuild and Other Stories (2 Viewers)

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Minor compared to the rapid progress that you have made, but I got the 3B reassembled yesterday and in the 70 to day.

In case you know better, I had to pull the starter off to make room to get the engine in the truck. I re-installed it before I installed the motor mounts while there was actually ample room.

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I'm interested in the interface between the arm and the valve tip per my contact picture above. The mechanical interface.

The newer units not being centered on the valve tip isn't ideal as a couple others have mentioned.

Since you're exploring overhauling the original rocker arms ask your machinist how they jig up the arms for machining to ensure the plane of the arm pivot is parallel to the rocker arm shoe face. While my engines aren't 100% apples to apples the tech is the same 1940's vintage. I see broken valve tips fairly regular when my customers use overhauled rocker arms that may not have a perfect pedigree. The typical cause is the plane of the shoe was not perfectly parallel to the arm pivot creating a side load on the valve tip, over time the stress breaks the tip off and drops the valve into the cylinder and makes for a bad day.
 
The newer units not being centered on the valve tip isn't ideal as a couple others have mentioned.

Since you're exploring overhauling the original rocker arms ask your machinist how they jig up the arms for machining to ensure the plane of the arm pivot is parallel to the rocker arm shoe face. While my engines aren't 100% apples to apples the tech is the same 1940's vintage. I see broken valve tips fairly regular when my customers use overhauled rocker arms that may not have a perfect pedigree. The typical cause is the plane of the shoe was not perfectly parallel to the arm pivot creating a side load on the valve tip, over time the stress breaks the tip off and drops the valve into the cylinder and makes for a bad day.
Lash caps may take care of this if they are an option???
 
The newer units not being centered on the valve tip isn't ideal as a couple others have mentioned.

Since you're exploring overhauling the original rocker arms ask your machinist how they jig up the arms for machining to ensure the plane of the arm pivot is parallel to the rocker arm shoe face. While my engines aren't 100% apples to apples the tech is the same 1940's vintage. I see broken valve tips fairly regular when my customers use overhauled rocker arms that may not have a perfect pedigree. The typical cause is the plane of the shoe was not perfectly parallel to the arm pivot creating a side load on the valve tip, over time the stress breaks the tip off and drops the valve into the cylinder and makes for a bad day.

Thank you Kris. Appreciate it my friend. Will pass along info to machinist today.
 
Minor compared to the rapid progress that you have made, but I got the 3B reassembled yesterday and in the 70 to day.

In case you know better, I had to pull the starter off to make room to get the engine in the truck. I re-installed it before I installed the motor mounts while there was actually ample room.

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Solid intel.

I put my starter on after motor mounts and a few other things. It was a biotch. This would have been much smarter.


@Onur I had my rocker arms re-ground and my rig had 485,000kms and looked worse than yours. The machinist said he had zero issues with doing that, and he's primarily a small/large/ag diesel machine shop.
 
Spoke to machinist today and said absolutely to use the correct arms that he will refurbish for me. He said contact has to be 100%. No exceptions.

Makes life easy.

Dropped off the liners I got from Dan at 4Wheel Auto in Canada. Great outfit. Can’t recommend him and his team enough.

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Since two projects are not enough, the man has started overhauling my raft trailer.

I said, "oh, you should take the 100 if you are getting lumber today."

"Nah," he said, "I'm good."

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Carbon offsetting the diesel rebuild :grinpimp:
 
Spoke to machinist today and said absolutely to use the correct arms that he will refurbish for me. He said contact has to be 100%. No exceptions.

Makes life easy.

Dropped off the liners I got from Dan at 4Wheel Auto in Canada. Great outfit. Can’t recommend him and his team enough.

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those are the exact same ones I used. So far they’ve worked out great.
 
those are the exact same ones I used. So far they’ve worked out great.

Thanks Ben. Yeah, these are the ones that come in the Engines Australia kits, so I am not concerned about their quality. Those guys have been doing diesel Land Cruiser engines for a long time. :)

In other news, @Indestructible 47 has shipped the bearing cap to me from Oz. Can't wait to get it and bring to machinist so he can get his butt in gear and get the block back to me.

Again, huge thanks to @Indestructible 47 for the massive assist here in finding the bearing cap. Owe you a few beers mate!! :)
 
that's interesting that's the rocker arm tip needs to have 100% contact area with the valve tip with the valve fully closed, which is when the rocker arm is exerting zero force on the valve stem (Valve lash, so clearance in that case). I would think the rocker arm would sweep over the area of the valve stem diameter through its travel being that it's a fixed length traveling around a fixed radius. Makes me want to open up a used engine and look.
 
that's interesting that's the rocker arm tip needs to have 100% contact area with the valve tip with the valve fully closed, which is when the rocker arm is exerting zero force on the valve stem (Valve lash, so clearance in that case). I would think the rocker arm would sweep over the area of the valve stem diameter through its travel being that it's a fixed length traveling around a fixed radius. Makes me want to open up a used engine and look.


Machinist stated that the surface area of the rocker arm had to be centered on the valve tip at its idle position (IE: adjusted per cold initial and hot operating specifications).
 
Interesting. Not arguing, just something I had never spent a moment of thought on before.
 
Sometimes not - :doh: When you get to your fence post project you're going to learn where your rocks areo_O
 
Thanks Ben. Yeah, these are the ones that come in the Engines Australia kits, so I am not concerned about their quality. Those guys have been doing diesel Land Cruiser engines for a long time. :)

In other news, @Indestructible 47 has shipped the bearing cap to me from Oz. Can't wait to get it and bring to machinist so he can get his butt in gear and get the block back to me.

Again, huge thanks to @Indestructible 47 for the massive assist here in finding the bearing cap. Owe you a few beers mate!! :)
No problems at all, glad to be helping out on such a cool build. Following with interest:cheers:
 
I thought I could build a 3B for under a thousad dolllars, no going to happen after all the machine work. The block was hot tanked and I willl make a home made pulller to extract and install sleves. You need to pull the oil injectors prior to pulling sleeves.
 
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