Engine Work - Update

[Jim Becker]

However many threads are engaged with the original bolt, an eighth shorter bolt will engage 2 fewer.

I imagine a head bolt with 200 ftlb of torque will be considerably bigger than the bolts in a Cub.

[Slim140]

You run the risk of stripping the threads out of the hole when you torque the bolts. You want as many threads engaged as possible.

Fair point.

At 16tpi, a 1/8" short bolt would miss 2 threads. This assumes that all threads are engaged with an OEM bolt. I haven't looked in the block to see if that's the case. We're torquing to 45ftlb. I'd have to imagine it would take a LOT of force in an iron block to strip the threads. We routinely see torque figures north of 100ftlb in other iron blocks, some closer to 200ftlb.

It's certainly a risk.

Even at 45 lbs you can stretch the bolt. Ask me how I know.

[Slim140]

Removed tape from painted parts this morning. After sitting in a hot barn all week, I thought they'd cure nicely...they did.

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Thanks.

Looking good!!!!

[PFord]

Even at 45 lbs you can stretch the bolt. Ask me how I know.

YIKES!! What kind of bolt was that and what went wrong?!

[Dale Finch]

One option some folks have used to "shorten" the head bolt (Instead of cutting) is to use a flat washer under the bolt head. I did that on a head bolt that I replaced due to some seeping... didn't know the history of the bolt, so replaced it instead of just removing, cleaning, sealing and reinstalling.

So far, so good!

[Stanton]

Thanks for the discussion on head bolts. Goes right along with this thread.

[PFord]

One option some folks have used to "shorten" the head bolt (Instead of cutting) is to use a flat washer under the bolt head. I did that on a head bolt that I replaced due to some seeping... didn't know the history of the bolt, so replaced it instead of just removing, cleaning, sealing and reinstalling.

So far, so good!

Goodness. Simple and elegant solution. Thanks for chiming in! I think that will be the ticket.

[PFord]

Thanks for the discussion on head bolts. Goes right along with this thread.

I appreciate you allowing us to barge in!

[Gary Dotson]

If you decide to use washers, just be sure to use hardened washers.

[Slim140]

Even at 45 lbs you can stretch the bolt. Ask me how I know.

YIKES!! What kind of bolt was that and what went wrong?!

That was a factory bolt and I tried to reuse it. Went with grade 9 instead.

[PFord]

Even at 45 lbs you can stretch the bolt. Ask me how I know.

YIKES!! What kind of bolt was that and what went wrong?!

That was a factory bolt and I tried to reuse it. Went with grade 9 instead.

Another reason I'm looking to go with new hardware. I just don't trust reusing them. Especially as these are likely almost 50 years old. Assuming of course there hasn't been a rebuild. I won't know that until I open it up.

[Clemsonfor]

You run the risk of stripping the threads out of the hole when you torque the bolts. You want as many threads engaged as possible.

Fair point.

At 16tpi, a 1/8" short bolt would miss 2 threads. This assumes that all threads are engaged with an OEM bolt. I haven't looked in the block to see if that's the case. We're torquing to 45ftlb. I'd have to imagine it would take a LOT of force in an iron block to strip the threads. We routinely see torque figures north of 100ftlb in other iron blocks, some closer to 200ftlb.

It's certainly a risk.

I have not built one of these engines or never anything other than bearing roll on a SBC. But I can't imagine 50# and 1/8" short would matter at 12hp.

[PFord]

I have not built one of these engines or never anything other than bearing roll on a SBC. But I can't imagine 50# and 1/8" short would matter at 12hp.

Well, that was my impression, but I'm new here and learning...

[Stanton]

Advanced a bit more today. Got the clutch assembly installed.

Clutch assembly ready to mount.

This plastic clutch alignment tool was included with the new clutch I bought from TM Tractor several years ago.

Clutch alignment tool.

I used a metal guide from a windshield wiper (tough metal!) to make this tool. It has a hook on one end for you finger and a 90 degree bend at the other which is exactly 1-1/4” from the tip to the inside of the bend. It’s mainly for adjusting the clutch fingers from the hand hole, not when the tractor is split. You can find it in the How To Forum.

Clutch finger depth tool.

With the tip of the tool touching the base and the top of the clutch finger snug against the inside of the tool, it’s at 1-1/4”.

Installed clutch assembly.

Ready to install engine to torque tube next…

[Stanton]

“I’d like to get Nellie back on her own 4 tires today,” was my thought and goal for today.

Started work on getting the governor back together on the bench. When things were running fine at disassemby, you think you can just reassemble and not loose any ground. But a close inspection is always a good idea while things are apart. Inspected the roller bearing and oil seal for the Governor’s throttle shaft. Found a leather seal (could be original to the ‘47), the roller bearings didn’t rotate and had a flat side on them, and the shaft was pitted where it met the leather seal.

First was to remove the oil seal so I could drive out the roller bearing.

Driving out roller bearing.

Here, you can see the bearing emerging as it’s driven out.

You can see the flat sides on the pins or rollers:

Flat sides on roller bearings.

Pitted shaft.

Time for a skim coat of JB Weld:

Mixing up some 6 minute JB Weld.

Skim coat…and let it dry.

Now, for mounting the engine to the clutch bell housing. This is a fun one-man job!

And if I wasn’t having enough fun, let’s mount the front axle/wheel assembly!

Front attached and torqued.

Mission accomplished for today’s goal. First time Nellie has set on her own 4 tires since this started…August of 2021. WOW! I’m embarrassed it’s taken this long. Sorry to drag this out on you all.