Gas engine overhaul

[Steelburner]

Thanks for the advice. I forgot to mention that the valve seats are being replaced. The shop that is doing the work on the head doesn't cut any corners. It is owned by a man who has a soft spot for old tractors. He will pressure test the head and everything. I supplied new guides also.

What is copper spray? I have never heard of it. I will have to check, but I think the head gaskets are John Deere.

Got a lot done tonight. Engine is on the stand and disassembled. The gear head stand was a good idea. I'm glad I didn't make one. I have seed on the interweb where someone used an airbrake slack adjuster as a makeshift worm drive on an engine stand. The hard part for me would be finding a splined shaft to mate with the slack adjuster. I thought it was a clever idea, though.

Now I have a lot of cleaning and measuring to do. The crank journals are smooth except for the rear thrust bearing. That one has a groove that is detectable with a fingernail, but not all the way around the circumference of the journal. The micrometer will tell me what needs to be done. The camshaft is out and I have to measure it up also. I was surprised how much corrosion was on the lobes. The tappets are an interesting design. Not at all what I expected.



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[Steelburner]

Head came home tonight. All new exhaust valves and one new intake valve that was burned badly. The larger valves are intake valves. New seats installed. New guides also. Milled .010" off to flatten. Intake and exhaust ports were trued also. One minor crack was fixed but I need to investigate where it was. It was somewhere in the #4 cylinder area. The head was pressure tested. Wallet is $600 lighter.

What kind of paint do you folks use on engines?

If I get the cam bearings and cam installed this weekend, I will be happy.

Edit: Forgot to add that the crank is getting ground. The shop that is doing the work is looking for main and rod bearings also. I thought this was a good idea because now they can match the crank grind to the bearings. The owner of the shop bought a 2010 crawler that he says was on pallets. Some assembly required!

[DrLoch]

Post up a picture of the pistons if you can. I'm curious to see what they look like. I've had pistons made in the past, granted it was auto motive related. Racing pistons aren't cheap either but if there is enough of a need someone can make them.

[Steelburner]

Busy weekend. I installed cam and bearings with a home made tool, installed the crankshaft even though I bought diesel bearings, installed the new deck and cylinders, took the oil pump apart and found that it is totally wrecked, and finished numerous small assemblies. I will post lots of pictures later, as I am exhausted. Anyone have an oil pump they can part with? I'm racing to get this thing done because I have been using my 7 year old daughter's wagon to store the finished assemblies. She has given me notice that she wants her wagon back. It was funny watching her expressions as she tried to pull it out of the garage with a head, crank, and cam in it.

[Steelburner]

First thing, I installed the cam bearings with a homemade tool. The bearing driver consists of 2 pieces of 1" coarse threaded rod, 3 hex nuts, and 2 homemade drivers.

The drivers are just big heavy washers. One is 2" diameter with a 1-1/16" hole drilled in the center and about 1" thick. The bearing driver is 1.925" diameter with a 1-1/16" hole in the center and also about 1" thick. I used a lathe to make them.

I used 2 pieces of 1" coarse threaded rod because I had them. They are 14" and 24" long. You can get away with just the 24" one, but it was easier to align the tool for the middle and front bearing with the 14" chunk.

To remove the front bearing, lock 2 nuts together on one end leaving 1" of thread protruding (1" is the thickness of the driver washer I made). Take the third nut and thread it on the other end of the rod to protect the threads. Now use this assembly and a hammer to drive the front cam bearing into the block.

To remove the middle and rear cam bearings use the threaded rod, driver washer, large washer and 2 nuts to pull the bearings out the front of the bosses. Take your time and check alignment by feel. They should come out relatively easily, so if you have to use excessive force, check your alignment.

To install the new cam bearings, use the driver washer, 2 nuts, appropriate threaded rod length and the large washer to pull the bearings into place from rear to front. Use electrical tape on the threads where the bearing is to protect the very soft bearings from accidental contact with the sharp threads of the rod. Install the bearings rear first (pull it until it is flush with the front of the bore), then middle (centered in bore), and then the front one (centered in bore). Use a Sharpie marker to mark the location of the oil holes to aid in alignment with the holes in the bearings. The front and rear bearings are very forgiving with alignment, but the center one is a bugger. Note that the front bearing is wider than the other two and the oil hole is NOT on center.

Next, clean up the tappets and install them. Make sure they slide up and down in their bores easily. Oil everything.

I cleaned up the lobes on the cam with Scotch Brite. I had to push gear onto the camshaft with a hydraulic press to compensate for wear in the thrust plate. Reference the service manual for specs. I then greased the bearing surfaces and cam lobes and oiled the bearings. Carefully install the camshaft slowly so as not to drag the sharp lobe edges across the soft bearings.

I measured the bearing surfaces on the camshaft and the bores of the new cam bearings before installation and was concerned with the relatively large tolerances. Because of wear, they were a bit on the loose side dimensionally. I was surprised how much the cam bearings shrunk after being installed. In the end, the cam slipped in with slight difficulty because of this shrinkage and resulting reduction in bearing tolerance. Everything went together with high precision and the cam rotates with no perceptable play whatsoever.


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[Steelburner]

Next step was to install the deck and cylinders. Pretty straight forward.

Run a tap in the head bolt holes and make sure they are clean.

Make sure the bottom bearing surfaces where the bottom cylinder seals sit are spotlessly clean and free of rust.

Clean the cosmoline off the deck and cylinders, dry, and put the bottom cylinder seals on the cylinders dry.

Grease the bearing surfaces in the block that mate with the cylinder seals and grease the outside of the seals. My reasoning is that I wanted the seals to stay put on the machined shoulder of the cylinders, but slide along everything else.

Don't forget to put the lower head gasket in place and carefully lower the cylinders into the block.

I didn't have any bolts short enough to hold the deck in place, so I used longer bolts and nuts like shown. The whole thing sits proud of the top of the block, and the head bolts smoosh the cylinder seals into their seats.

The last photo is of the joint between the cylinders and the bores. There is a machined lip in the deck not a through hole as I expected. The cylinders must be brazed into place from the looks of the brass colored metal. Maybe its a washer?

I'll post the crankshaft installation tomorrow.


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[Steelburner]

The crankshaft bearings and crankshaft went in pretty smoothly. It took a little fidgeting to get the crank gear and cam gear to mesh correctly on the marks. Once again, the sharpie made it much simpler, especially since I didn't remove the oil slinger on the crank.

The only hickup came when I installed the bearings into the caps. I had the machine shop that ground the crank order the bearings so they could match dimensions. My crawler is gasoline powered and they gave me diesel bearings (I think). The oil groove in the original bearings are not in the cap-half of the new bearings. They are perfectly smooth on the cap bearing. The smooth halves are cap bearings because there are no oil holes. I also had to file the tab to make it fit in the recess in the caps. I just held the bearing in place and marked the groove width onto the bearing and carefully filed it to width.

I think these bearings will be OK. The only issue I have is the rod bearings are fed through these oil grooves through holes drilled in the crank throws. With only 1/2 a groove, the rods will be pressure lubricated only half the time. I still think the oil film will protect the rods during these "dry" periods of rotation. I'm thinking this should increase oil pressure overall. I also took into consideration that diesel bearings take more abuse than a gasoline engine, so they should be alright. What do you guys think?

Pistons arrived tonight and it is supposed to rain tomorrow. I hope to get them installed tomorrow. I will post pictures of the old pistons then. How do you grind the rings when adjusting the gap?

I had a panic attack when I took the oil pump apart and found it in very bad shape. It looked as if something got stuck in the gears and pushed the driven gear into the side of the pump bore and ground off part of the gear lobes. It also scored the bore and shaft badly. The shaft bore is no longer round either. These pumps are hard to find, but with Lavoy's help, one is on the way. Thank you Lavoy. You have helped me more than once with this project. John Deere wants over $1000 for a new complete pump. I don't think I could just replace the gears with the scoring in the pump body itself. I've been pestering my motorhead friends about substitute pump gears. Does anyone have any thoughts on a source for gears that could be modified to work in a 1010 engine? Longer gears can be cut down and axle bores can be drilled and reamed or sleeved as required. I was even looking at small hydraulic pumps for these gears. Anyone have any thoughts?

The service manual cautions about using a diesel oil pump in the gasoline motor. What is the difference between the two?


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[Steelburner]

I forgot to add that the surfaces for the front and rear crankshaft seals are deeply grooved, but smooth. The machine shop suggested Speedi Sleeves, and I had to look up what that is. Has anyone used these before? There is a lot of extra room in the way the seals are pressed into the seal holders. I am banking that I will be able to press the seals in deeper so they ride on virgin surfaces. I'll let you know how that works out.

Another thought: I painted the flywheel a bright orange with a contrasting color on the timing marks for easier visibility (and I wanted to get rid of some Ariens paint). When I tried to check engine timing before the overhaul, I found it very difficult to get a timing light focused down the inspection hole. The A-frame for the loader arms is right in the way. Is there a trick with a mirror to accomplish timing adjustments using a timing light?

Since the computerization of vehicles became the norm, I am delighted to reuse my old tune-up equipment that has been sitting around for years. My truck has 4 computers in it, for crying out loud! I have an old dwell meter that was my grandfather's. Can't remember how to use it, though. Never throw anything away!

[shinnery]

As I remember it a dwell meter is just measuring the precentage of time your points are closed. A full scale reading means the points are closed all the time. In fact there should be an adjustment for full scale when the points are closed and the engine is not being turned. Then spin the engine and read the correct dwell scale for a four cylinder engine.
Bryce

[jtrichard]

the oil pumps are the same (gas and diesel) only difference is the drive gear there are two pumps on ebay also the pumps are the same 1010 vs 2010 early 1010 used a different pump ...the main bearings are the same gas or diesel only the gas takes 2 less ..... I be live the mains with both half's with oil grove are the early ones the later ones only have grove in the top half the rods are all the same gas/diesel 1010/2010 ....cam and bearings are the same 1010/2010...speedi sleeve is the way to go

[DrLoch]

Like the pictures and commentary....

[DrLoch]

No more updates...?

[Steelburner]

Sorry for the lack of updates. Been very busy. Here are the images of the original pistons:


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The new pistons are cam ground. This means they are oval shape, with the widest part installed perpendicular to the crankshaft. Also, I was worried about gapping the rings. After reading the service manual, I learned they come pre-gapped. Make sure to follow the installation instructions that come with the rings, as they differ slightly from the service manual. My service manual, at least. I reused the rod bushings, as there was little to no wear.

New pistons:


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[Steelburner]

Head is on and torqued down. The service manual says that you are supposed to retorque after so many hours of operation (I cannot remember how many hours at the moment). I don't know how you are supposed to accomplish this, as the rocker tube blocks half of the bolts. The rocker tube is only held on by 4 bolts, so it wouldn't be too hard to remove. You might as well adjust the valves again, anyway. The coolant manifold covers the other half of the head bolts. Make sure to install the rocker tube studs with the stud that has the side milled away in the rear hole. This is where the oil port is that feeds oil to the rocker arm tube and then the rockers. Align the flat with the oil port plug in the rear-right side of the head. Reference the photo. It's easier to show than explain.


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My photo of the oil port plug might be a little confusing without an explanation. I made new rocker cover studs because the originals were pretty buggered up. I made the new ones out of 7/16"-14 X 6" grade 8 bolts that I cut the heads off of and threaded with a 7/16"-20 die. The photo shows the stud bottomed out in the head so I could mark the alignment with the oil port in the head. I then ground the flat with a grinder and smoothed with a hand file. The original studs do not bottom out, but since the service manual says you are supposed to lift the entire engine and radiator by these 7/16" studs, the extra thread engagement cannot hurt.

[Steelburner]

The rockers themselves needed a little attention because of deep grooving by the original valve stems. I ground them flat with a die grinder and a Green Corps disk until flat and then polished them with a very fine grit Roloc disk. This worked well and I was able to preserve the original curve of the contact points.

Something I hadn't noticed before is how the intake rockers are marked with notches.

I also replaced the corks with home made steel plugs. They are 5/8" O.D. round rod 1/2" long with a groove turned in them for a 5/8" O.D. x 3/16" o-ring. The groove is .085" deep. Be careful to remove the burr on the cotter pin holes before you rip all your o-rings like I did. Grease them up well before installation. A blind hole tapped into these plugs would also be a good idea.


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