Cub engine questions

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carmanic
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Cub engine questions

Postby carmanic » Thu Dec 06, 2018 1:37 pm

Hello All, I'm in the process of resurrecting a '58 Lo-Boy that "ran when parked" (unfortunately that was outside and 15+yrs ago), and have a few engine-related questions;

1. What is generally considered an "acceptable" low-end compression reading ?
2. Same question regarding oil pressure ?
3. Can the valve clearances be set w/o removing the carb or manifolds ?

Thanks in advance, more to follow.
Daren

inairam
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Tractors Owned: 1948 with international 1000 loader 6v - Dozer
1949 with kub klipper belly mower. mag 6v - Mom
1950 with plow, 54 blade, mott mag 6v - Roxanne
1953 54 blade, c22, wood 42 6v
1957 with c-2 mower & c-54 grader blade 6v - barn Queen
1965 lo-boy with c-3 mower 12 v - Loboy
1975 with homemade mower 12 v - Horse
1979 long strip 12 v
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Location: Glen Mills PA

Re: Cub engine questions

Postby inairam » Thu Dec 06, 2018 3:35 pm

See what to do with the cub you just brought home

[quote="carmanic"]

1. What is generally considered an "acceptable" low-end compression reading ?

When it is extremely hard to start, have heavy blue smoke or when is does not have the power to do what you want.
The most important thing is the number is consistent in all 4 cylinders. 85 83 87 85 is better than 100 80 45 95
If it has not run for 15+ years I would get it running and use a lot of seafoam in the gas and oil for a while and then see what the compression is.

2. Same question regarding oil pressure ?

Again get it running and loosed up before you worry about the pressure. As long as the needle moves.

Make sure you prime the oil pump. It has been sitting for a while. I would also change the oil.


3. Can the valve clearances be set w/o removing the carb or manifolds ?

you do not need to remove anything but the valve cover but is it a lot more difficult with the carb in the way. You do not need to remove the manifold.

I think the manual says 0,013" I tend to go 0.015. I would adjust the valves after it ran for a bit with seafoam in the fuel and oil and before I did a serious compression test.
When you only have 9 horsepower you need to know the names of all of the ponies!

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Glen
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Re: Cub engine questions

Postby Glen » Thu Dec 06, 2018 7:48 pm

Hi,
Below is a post I made about priming the oil pump, it is about half way down the page.

viewtopic.php?f=1&t=91765&start=60

The Cub service manual says a Cub engine has 120 lbs of compression, that is probably for a new engine. Some less is ok, they still work.

I would give the engine a tune up, Cubs need a tune up, like cars years ago that had distributors, and ignition points. The points could be corroded from sitting, then it won't run.

Below is the 1957 Cub LoBoy owner's manual, the experts on here recommend reading it. It has lots of info about operation, maintenance, and lubrication. There is a table of contents on page 1.

http://farmallcub.com/rudi_cub/www.clea ... index.html

It probably has a Battery Ignition unit, the info for those starts on page 42. It shows the points there, and setting the point gap.
You can file the points if they are not burned too much, or replace them. I usually take them out to file them, the metal is usually hard, I hold one piece at a time on a hard surface and file it flat with a large flat file. Wipe off all filings with a clean rag.
It could have a magneto, they are in the manual too. Identify which it is, and disregard the info for the one you don't have.

Below is a listing at TM Tractor for new points and condenser, you can look at them.

http://www.tmtractor.com/new/el/367fp.htm

The engine needs the timing set with a timing light after setting the point gap, and replacing other parts. The distributor cap, rotor, spark plug wires, and spark plugs, might need replacing too.
You should take out the spark plugs and see how they look, clean them, and set the gaps. Or replace them if needed.
Clean all dirt from around the spark plugs before removing them, so it doesn't fall into the engine.

Lube the fan, if it still has the original style fan. They use motor oil. It shows how in the owner's manual. People have posted on here about fans that seized from low oil in them. Good luck with the LoBoy. :)

jsfarmall
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Re: Cub engine questions

Postby jsfarmall » Thu Dec 06, 2018 8:27 pm

Just unbolt the valve cover and let it drop down. If you have touch control it will sit right in behind the hydraulic lines. Will give you room to adjust. Absolutely prime oil pump first as stated above. As long as your oil gauge moves out of the red you have enough pressure.

carmanic
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Re: Cub engine questions

Postby carmanic » Tue Dec 11, 2018 1:55 pm

Many thanks for the replies to my Cub engine questions. I've actually been working on this tractor for about a year and so have already done most if not all of the things recommended. So far I've replaced or rebuilt the starter, carburetor, intake hoses, cooling hoses, plugs, cap, rotor, points, condensor, plug wires, coil and battery. I've lubed all the engine points, changed the oil & filter and primed the heck out of the oil pump, but have not been able to get any oil pressure. Even tried cranking w/the gauge removed but not a drop came out of the hole. Next up will be to remove & clean the oil pressure relief valve & drop the pan to clean it and the oil pump pick up, then adjust the valve clearances which will hopefully bring the compression more to even (90, 65, 30, 95 with MMO in the cylinders). Even if I still don't have oil pressure at that point I'll try to start it to see if running will create oil pressure. Stay tuned.

Daren

inairam
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Joined: Wed Jul 08, 2015 10:24 am
Zip Code: 19342
Tractors Owned: 1948 with international 1000 loader 6v - Dozer
1949 with kub klipper belly mower. mag 6v - Mom
1950 with plow, 54 blade, mott mag 6v - Roxanne
1953 54 blade, c22, wood 42 6v
1957 with c-2 mower & c-54 grader blade 6v - barn Queen
1965 lo-boy with c-3 mower 12 v - Loboy
1975 with homemade mower 12 v - Horse
1979 long strip 12 v
Memberships: Rough and Tumble Engineers Historical Association;Chapter 8 IH Collectors; IH Collectors Worldwide
Circle of Safety: Y
Location: Glen Mills PA

Re: Cub engine questions

Postby inairam » Tue Dec 11, 2018 2:09 pm

It sometimes takes a minute or so to get the gauge to read.

If the oil pump is primed and you see oil coming out of the hole when you crank it on the starter I would try to start it and not worry about the oil pressure until a minute or two in.

What weight oil are you using?
When you only have 9 horsepower you need to know the names of all of the ponies!

carmanic
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Re: Cub engine questions

Postby carmanic » Fri Dec 14, 2018 1:12 pm

Pump is primed but there is nary a drop of oil coming out of the gauge hole when cranking. IIRC I'm running 10w-30.

Current plan for the weekend is to adjust the valve clearances, check & clean out the oil pressure relief valve and then drop the pan to clean it and the oil pickup. Assuming I don't find anything bad I'll reprime the oil pump and try to start it. Cross fingers, stay tuned.

Daren

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Re: Cub engine questions

Postby Eugene » Fri Dec 14, 2018 6:28 pm

carmanic wrote:Pump is primed but there is nary a drop of oil coming out of the gauge hole when cranking.
Remove the oil filter cover. Look inside, down about 1 1/2 inches to the front of the tractor. There is an opening there. If the oil pump is working, oil will come out of that hole.

If the oil galleries are dry, it will take a few seconds of engine cranking before oil appears.

You can also prime the oil pump through that hole.
I have an excuse. CRS.

inairam
501 Club
501 Club
Posts: 1090
Joined: Wed Jul 08, 2015 10:24 am
Zip Code: 19342
Tractors Owned: 1948 with international 1000 loader 6v - Dozer
1949 with kub klipper belly mower. mag 6v - Mom
1950 with plow, 54 blade, mott mag 6v - Roxanne
1953 54 blade, c22, wood 42 6v
1957 with c-2 mower & c-54 grader blade 6v - barn Queen
1965 lo-boy with c-3 mower 12 v - Loboy
1975 with homemade mower 12 v - Horse
1979 long strip 12 v
Memberships: Rough and Tumble Engineers Historical Association;Chapter 8 IH Collectors; IH Collectors Worldwide
Circle of Safety: Y
Location: Glen Mills PA

Re: Cub engine questions

Postby inairam » Sat Dec 15, 2018 7:27 am

Be careful pulling the oil pan. It is not hard to snap those bolts. You may also want to invest in a "Universal Joint Socket Set" 1/4" to get some of them out and back in.

If it were mine I would fire it up with seafoam in the oil and a detergent oil to clean the oil pressure valve and oil uptake. I would do that instead of risking taking off the oil pan just to clean it. If you had another reason OK clean it but cleaning would not be my primary reason for removal.

I would be more concerned about oil coming out of the priming hole than the oil gauge hole. http://www.farmallcub.com/phpBB2/viewtopic.php?t=94417. If you have oiling coming out of the priming hole on the on the starter it is safe to fire up.

You may not be able to generate enough pressure on the starter to get anything to the gauge. Like I said the oil pressure is very low for the first few moments after a start.
When you only have 9 horsepower you need to know the names of all of the ponies!

carmanic
Posts: 6
Joined: Thu Dec 28, 2017 3:08 pm
Zip Code: 95249

Re: Cub engine questions

Postby carmanic » Tue Dec 18, 2018 3:14 pm

Eugene wrote:
carmanic wrote:Pump is primed but there is nary a drop of oil coming out of the gauge hole when cranking.
Remove the oil filter cover. Look inside, down about 1 1/2 inches to the front of the tractor. There is an opening there. If the oil pump is working, oil will come out of that hole.

If the oil galleries are dry, it will take a few seconds of engine cranking before oil appears.

You can also prime the oil pump through that hole.


I have primed the system through that hole until oil came back out, then cranked until the cows came home but no sign of oil pressure. My friend that I got this tractor from may not have been mechanically inclined but I cannot believe he'd use this tractor as he did if it didn't show oil pressure on the gauge. So still I am hopeful that it's just that it's been sitting lo these many years.

carmanic
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Re: Cub engine questions

Postby carmanic » Tue Dec 18, 2018 3:20 pm

inairam wrote:Be careful pulling the oil pan. It is not hard to snap those bolts. You may also want to invest in a "Universal Joint Socket Set" 1/4" to get some of them out and back in.

If it were mine I would fire it up with seafoam in the oil and a detergent oil to clean the oil pressure valve and oil uptake. I would do that instead of risking taking off the oil pan just to clean it. If you had another reason OK clean it but cleaning would not be my primary reason for removal.

I would be more concerned about oil coming out of the priming hole than the oil gauge hole. viewtopic.php?t=94417. If you have oiling coming out of the priming hole on the on the starter it is safe to fire up.

You may not be able to generate enough pressure on the starter to get anything to the gauge. Like I said the oil pressure is very low for the first few moments after a start.


I don't have another reason for pulling the pan other than ensuring it and the oil pickup are clean. I tend to go a little deep on my projects and in this case just don't want to overlook sometime that causes me to have to consider an engine rebuild. Given everything, I think I'll leave it as is for the time being and continue my Cub homework. Thanks all ~

Daren

inairam
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Posts: 1090
Joined: Wed Jul 08, 2015 10:24 am
Zip Code: 19342
Tractors Owned: 1948 with international 1000 loader 6v - Dozer
1949 with kub klipper belly mower. mag 6v - Mom
1950 with plow, 54 blade, mott mag 6v - Roxanne
1953 54 blade, c22, wood 42 6v
1957 with c-2 mower & c-54 grader blade 6v - barn Queen
1965 lo-boy with c-3 mower 12 v - Loboy
1975 with homemade mower 12 v - Horse
1979 long strip 12 v
Memberships: Rough and Tumble Engineers Historical Association;Chapter 8 IH Collectors; IH Collectors Worldwide
Circle of Safety: Y
Location: Glen Mills PA

Re: Cub engine questions

Postby inairam » Tue Dec 18, 2018 5:05 pm

I just did work on my brother in laws tractor. I had the hood off and was pulling the starter lever with my hand while looking at the oil pressure gauge

Zero pressure cranking on the battery. low pressure on 1/3 throttle but out of the red and this Cub goes all the way up on when you go over 1/2 throttle.

Fire that puppy up and enjoy it!

Do not worry about the oil pressure until untill it it has been running for a few minutes.
When you only have 9 horsepower you need to know the names of all of the ponies!

outdoors4evr
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Re: Cub engine questions

Postby outdoors4evr » Wed Dec 19, 2018 8:50 am

If your compression #'s are low, it may help to put a tablespoon of oil in each of the cylinders to raise the compression and get it started.
Some also have more success getting them to fire by pull starting the first time. Note: attach tow rope to the drawbar (rear of the tractor) not to the front.
184 w/ Creeper & 3-Point
IH 3160a Mower
IH Model 15 Tiller
IH-54 Blade

carmanic
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Re: Cub engine questions *IT'S ALIVE*

Postby carmanic » Thu Jan 03, 2019 1:32 pm

Just wanted to thank you all for the advice and encouragement regarding restarting my '58 Lo-Boy. Over the Holiday break I adjusted the valve clearances, primed the oil system, cobbed up a fuel feed, hot-wired the coil, crossed my fingers and pulled the starter switch.

It caught on the second pull, filling the air with an acrid cloud of white smoke as it chuffed away for the first time in nearly 20 years. Then as the smoke gradually diminished, I noticed it had oil pressure. Happy happy. Stay tuned for more newbie questions as the resurrection continues.

Daren

xraycajun
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Re: Cub engine questions

Postby xraycajun » Thu Jan 03, 2019 2:31 pm

I never had oil pressure on cranking. On my cub, the pressure builds in the first 60 seconds after startup.


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