Engine Work - Update

[ricky racer]

Hi,
Before you put the front cover on the engine, check to see if the oil passage plug is there, it is behind where the camshaft gear would be.

Below is a pic from TM Tractor showing it, it is to the upper left of the camshaft hole, left in the picture.

There are other plugs on the engine, one is in the area with the valve springs.

The plug Glen mentioned above is the only 1/4" NPT oil passage plug in the engine. All the rest are 1/8" NPT.

[Gary Dotson]

I can’t stress Tim’s suggestion strong enough! I had a Chevy block done at a very reputable shop and even further flushed the galley, after getting it home. Debris made itself known, on start-up, taking out the main bearings. That one cost me $.

[Stanton]

Great advice.

The machinist questioned me when I picked it up. He showed me the oil galley plugs but was worried about an open hole at the front end of the valve chamber. I told him it was where the air tube connects from the air intake to the block. He was relieved he hadn’t lost a plug.

I’m making a list, so appreciate all the great pointers.

[Stanton]

Stanton are you reusing your old cam? Are even new ones available along with lifters?

Yes, reusing the old cam shaft. Using this for bearing reassembly grease:

[Stanton]

OK, so there's no time like the present, right? Christmas Eve is here, we've got all our chores done, presents wrapped, goodies baked, and now we have this day to do something. Think I'll start putting the engine back together. Was in the mid-60s this morning and predicted to hit 70 this afternoon. Very humid and breezy.

Started by accessing everything. Been a while since I've brought this engine back home from the machine shop, so some of the exposed metal surfaces don't look as shiny as I'd like; need to clean them up. Went back through the comments above and compiled this list:

1. Blow out (clean) all oil galley passages. There could be metal shavings or particles that need to be removed.
2. Make sure all three oil plugs are in place (a 1/4"NPT behind the cam gear, a 1/8"NPT next to the top of the oil filter opening and a 1/8"NPT plug on the front right near the top corner).
3. Use Plastigage (green) to double check clearances of bearings on both crank and rods.
4. When installing the rings, stager the oil rings an inch or so apart.
5. Use bearing assembly lube or 80W-90 oil. Stays in place longer and will help on initial start-up.
6. Use zinc additive in oil on start-up to help lube the cam shaft lobes.

Removed all 3 oil plugs and used compressed air to blow out the oil passages. Didn't know if that is sufficient or if it needs to have a pipe cleaner or similar rodded in there. What's your experience?

Overall starting point.

Engine front including 1/4" NPT oil plug.

Removed all oil plugs and cleaned with compressed air.

Polished the crankshaft bearing retainers and oiled them up. We've had a really high humidity day here, so don't want them to rust. Will wipe them down before using Plastigage and installing bearings.

Started wire wheeling the crank bearing retainers.

Cleaned, polished, and oiled.

Thought now would be a good time to clean out all the exposed bolt holes. I have several different diameter sizes in a set I bought from Northern Tool; great for cleaning. Did all the head bolt holes, pan bolt holes, etc.

While exposed, used a wire brush to clean all threaded holes.

Used compressed air several times to blow and re-blow passages, bores, and nooks out. Trying to get this as clean as possible.

All blown out with compressed air, ready for the next step.

Will post more.

[ricky racer]

Sounds like you've got everything under control. I always enjoy the assembly phase of a build. I like fitting everything and making sure everything is a nice fit and goes together well.

You should check the end gap of each of the rings before installing them. Placing each ring in a bore and square them up by slipping a piston in the bore to make sure it's setting square with the bore.

You can also then take one of the rings (once you've measured the end gap) and move it from bore to bore, measure the end gap and verify that the bore diameters are all consistent.

[Stanton]

After lunch, got all the crank shaft bearings laid out.

Then proceeded to Plastigage each bearing to ensure clearances. Bearings #1 & #3 were .003, and #2 was .002; within spec. I lubed the bearings and shaft up with engine lube and torqued the bearing cap screws down to 55-60 ft lbs per spec.

Green Plastigage ready to do its job.

Bearing #1.

Bearing #2.

Bearing #3.

Bearing retainers lubed.

Crank shaft back in place.

Next was the valve tappets, lubed and dropped into place. Then the cam shaft was lubed and installed.

Valve tappets were lubed and inserted.

Last thing today was installing the idler gear and ensuring all the timing marks lined up.

Timing marks all align.

I was looking at the new connecting rod bushings and the old ones still in place. I was hoping to install new bushings, but don't want to screw it up. I'll have to dig around the Forum to see how to remove the old bushings.

[Don McCombs]

Stanton, thank you for the photos showing how to use the Plastigage. Having never done that before, it was very instructive.

[Eugene]

I was looking at the new connecting rod bushings and the old ones still in place. I was hoping to install new bushings, but don't want to screw it up. I'll have to dig around the Forum to see how to remove the old bushings.

Wrist pin bushing.

Bushing removal/driver set.

[Glen]

Hi,
The Cub and LoBoy service manual has info about the piston ring end gaps, be sure they have the right end gaps when in the cylinders. Put them squarely into the cylinders, off of the pistons.
If you have a flat top piston, you can use it, upside down, to push the new rings into the cylinder.
Be sure the rings have end gaps at several positions in the cylinders.
Use a flat feeler gauge to measure the gaps.
Info is below on page 1-29.

http://farmallcub.com/rudi_cub/www.clea ... -01-29.jpg

The specs for the end gaps are on page 1-6.

http://farmallcub.com/rudi_cub/www.clea ... -01-06.jpg

Info for ring end gap positions, when they are installed on the pistons, is on page 1-30, at paragraph 4 and down. It is different than what was said in the post above.

http://farmallcub.com/rudi_cub/www.clea ... -01-30.jpg

[Stanton]

Thanks, Glen. Am using the Service Manual as I go, just as you suggested.

[ricky racer]

If the ring manufacturer calls out a ring gap different than what is shown in the manual, follow the manufacturer's specification. Ring materials may have changed a bit over the last 70 years.

[Stanton]

Well, with life’s recent health hiccups, I managed to get a very nice, warm day combined with energy to take another step forward.

The first wrist pin was tight (too tight IMO) when I tried inserting it in the piston a few weeks ago. I set it aside, intending on referencing my old set, but life got in the way. Today, I answered the question that the wrist pins should be snug in the piston hole, not enough to press, but maybe tap. That first and third one was tight, the second and fourth I could push in without much difficulty. Set the spring retainers. Lubed them all with engine assembly as I went.
Ready to start putting on rings and getting those end clearances correct.

[Dale Finch]

Oooo..so purdy!! You have more energy than I on this snowy day! You're doing great, Stanton...Congrats!

[tst]

many times after replacing rod bushings they need to be fitted or burnished to fit correctly, stager piston rings so the ends to not line up with each other, 3 piece oil rings have a much wider gap than one piece rings, up to .035 I have found on most