This engine work has me missing the rust repair last winter... It was nice when I found something wrong i simply took a grinder to it and then welded over it. If it doesn't work right, it hit with a hammer until it does, haha!
This engine work has me missing the rust repair last winter... It was nice when I found something wrong i simply took a grinder to it and then welded over it. If it doesn't work right, it hit with a hammer until it does, haha!
There is only one way to do it right '56. If you were satisfied with the way it was running, you probably shouldn't have taken it apart. Getting It to run correctly without reconditioning the bores is not going to happen. The piston you have photographed below clearly indicates that cylinder Definitely needs to be bored and honed and a new oversize piston installed. The ridge you indicate is present in the other cylinders, tells the story on those cylinders, they are also worn out. I would say you may have been happy with the way it was running but, in no way was it running well. I can tell you if all 4 cylinders and the valves were sealing correctly, it would have been running Much, Much better. The blown piston and rings and the condition of the other bores, create a lot of crankcase pressure and force oil and gasses past the gaskets and seals. This creates a very leaky engine with dirty oil, that wont seal up no mater what you use for gaskets. Everything has a cause and effect. Swapping in a good running engine is also a great way to save time and money. Just be sure to run a leak down on the used engine. You don't want to put in a motor that has poor combustion sealing.
In regards to the LS junkyard videos, I enjoy them. They sell a lot of junk yard parts. They show how to do it if you want to roll the dice. For everyone of those videos, there are hundreds who lost their humor for them when things didn't work that way for very long. If you are satisfied with your "rebuild" fouling plugs smoking a little, leaking, and dirtying the oil very quickly and lasting for just a few thousand miles, have at it. I will take the correct job every time. If those videos were the way to go, we wouldn't need new parts or machine shops.
The most important thing here is that you have fun with it. A hacked up rebuild will often "take the fun out of it". It might on the other hand last a few thousand more miles. You should do what you want with it. Give it your best thought process and give it a go. This is how some of us learn.
Last edited by bmorgil; 02-08-2025 at 08:49 AM.
Thanks again, I apologize if my previous post may have sounded out of line. I guess i just need to make a decision, because I really don't want to get into an engine swap now, but in the future might be cool. To be honest, the engine is mostly why i bought the jeep, the body was junk, the brakes/wiring was junk everything was junk. But yet that engine started up and ran amazingly. Yet here I am with every else on the jeep completely rebuilt, and the engine is bad. I don't see how it makes since to invest in this engine, if I decide to completely get rid of it, a couples years down the line. Your right, I probably shouldn't have taken it apart, I just wanted to fix a rear main seal, and tidy up a couple things. Had i left it alone other than oil leaks, I would have trusted it for a cross country road trip, haha! I wasn't expecting to find pieces of piston gone. And I figured since I know it ran and had good compression, there wouldn't be any issues. As far as the ridges on the cylinders, there really isn't much. You can BARELY I mean barely feel it. I've assisted friends tear apart 1980s era ford v8s that had WAY more ridge. My brother has a basic bore guage, I'll try and measure for taper. I think the manual says it should be within 0.005". It won't be the most perfect measure, but it will get me an idea, and this old of an engine has pretty loose tolerances anyway, I feel.
Last edited by 56willys; 02-08-2025 at 10:05 AM.
A few things to keep in mind '56.
Cylinders wear at the top in the first 1/4 to 1/2 inch of piston ring travel. This is where combustion pressure is sufficient to push the rings against the wall creating the seal. It is normal to still see the original cross hatch of the honing well down in the cylinder bore with the top worn out. This is the reason for the taper specification. The cylinder will be close to original and unworn at the bottom, and worn the most at the top where the rings are under pressure. Little wear occurs once combustion pressure drops after the first few degrees of motion. .005" of wear in the cylinder is .0025" of wear per side. You cannot feel .0025". If you can feel a ridge, it is much more than that. At this point you are definitely at a crossroads. We haven't discussed the condition of the crank. I can visually see it needs to be turned.
The "quickest way to at least do a half way decent job would be to:
Bore and hone the block, your cylinders are worn out and one is damaged badly by the broken piston. Have the machinist tell you how far oversize it needs to go and get new pistons and rings.
Have a valve job done on the head for the intakes, and the block for the exhaust. If the valves check out OK for reconditioning, have them ground.
Have the guides checked in both and replace if needed. Stay away from "Knurling".
Turn the the crank journals. The machine shop will tell you how far under size they needed to go so you can get the correct bearings.
Have the block deck and the head resurfaced to flat, so you aren't fighting head gaskets.
Anything less than this could be a recipe for disaster. Here is what you must take into consideration. Combustion temperatures will exceed 2000 deg. Fahrenheit. When you have a good seal at the rings and valves, not only will it make more power but most important, It will last. When things start leaking the hot 2000 deg. combustion gasses, the wear goes up tremendously. The hot gasses are sent into the crankcase where they burn and contaminate the oil and cause the bearings to wear. As the gasses shoot by the leaky rings and valves, they will "flame cut" the components wearing things faster and faster. As combustion pressure drops, the clean burn becomes not so clean, further contaminating oil and and wearing the bores and rings. The scratches on the bearing surfaces cause pressure loss and sporadic oil film strength which leads to the bearings burning up and spinning. So will it run with a half job? Of course it will, as long as it seals enough to create combustion. For how long? That is truly a guess.
I am not trying to "harp" on you '56, just trying to keep you out of trouble! I am very pleased that you are so into this. So many pound their way through and ruin a lot. Throwing good money after bad. I would feel bad if I lead you to believe a proper job isn't needed. As I said before, an engine with leaking combustion and scratched up bearing surfaces will run. Not well and not for as long as it could. I would be lying to you if I told you I haven't done what you are contemplating. I would tell you however, it turned out exactly as the the teachers teach will happen. The old saying fits very well here. "A good job need not be done again". I have redone more than one backyard "rebuild" that didn't work out for someone. It cost much more the second time around. Now if you are just trying to make it run so you can get rid of it, lots of people have done that. Buyer beware!
Last edited by bmorgil; 02-08-2025 at 04:11 PM.
Your helping me, I REALLY appreciate that, I can't say how much I wish I could get a perfect job done. The problem is with me, flossy is my only running (it was) vehicle. I also have an old van that a friend gave me that will eventually be flossys towing rig. That project I just got last summer and it's been untouched for 20 years, it was free, they wanted it out of their yard and it was to good to scrap. Luckily it doesn't require much monetary input, just time. The big thing is I'll need a daily driver in a couple months, so the more I spend on this hurricane the less I can spend on a reliable daily. And in my failing attempt to be responsible, haha! I should be focusing on a driveable vehicle, not a 70 year old basket case, haha! I can't help it I'm addicted to old cars! And I pulled the engine thinking it would just be 100 bucks in gaskets and I'm back on the road, well, that escalated quickly! In a matter of 1 day I went from spending a couple hundred to spending a couple thousand dollars, so it's just a pretty big disappointment, that's all.
I did some work today, I didn't get any photos so I'll wait to go into detail until I take a camera out. But I got the other 3 pistons out, that was interesting (I'll wait for photos of that) then I pulled the main caps off one at a time. And followed the instructions in the manual for checking crankshaft run-out. And it actually checks out good, an the main bearings look okay. I pulled the rear main and it actually has a rubber seal. Did willys ever use rubber/neoprene rear main seals, or has someone changed it?
Last edited by 56willys; 02-08-2025 at 11:21 PM.
Next thing, I still can't get that oil pump out! I removed the 3 bolts that go into the block and I've been tapping a plastic coated dead blow hammer around it, it just won't budge. I've just lightly tapped it, I'm afraid to use more force, but I might have to. Is there anything I could be missing, or something I could try?
I do really appreciate your help here, no matter what I end up doing, it's still a learning process.
I'm going to call a local engine builder on Monday, and get a ballpark price for some machine work. At the very least have him grind the crank, do a valve job, and fix the bores. I want to do as much of the work myself as possible, it's cheaper, but mostly so I get experience.
Last edited by 56willys; 02-08-2025 at 10:53 PM.
Yes Willys started out with the rope seal like most automotive manufacturers of that era. Sometime, (it looks like in the late 50's) in later models Willys switched to the two piece neoprene seal.Originally Posted by 56willys
The oil pump has a long snout that is in the block. It sounds like it is stuck in the block. The technique to get it loose would be similar to getting a stuck distributor out. It is a bit unusual to have the oil pump get stuck but... Some heat on the block and some penetrating oil, and keep trying to wiggle it back and forth till it breaks loose from the block.
Every time I tear into an engine I learn something '56!
You have a good plan '56. Doing everything but the machine work yourself, is the way to save money. Taking your time like you are, and checking your process will save you a lot of headaches. I think you can get it done for less than you think. Head down, keep swinging '56!
Thanks mate! Hopefully it turns out okay. My main concern (it may sound silly) is getting to the Bantam Jeep fest this June. I've been going there since I was 3 and always dreamt of driving my own jeep. I got the opportunity to have my jeep there the past two years, but I couldn't drive for age requirements. This will be the first year, I'm old enough to drive Flossy. If I don't make it, it's not the end of the world and I'll just hit it harder next year. But it'd be super cool to make it there. Fingers crossed I can get things sorted out relatively well, and get a good engine. With how it ran before, if the issues it has really caused that much loss in performance. It should feel supercharged after this. It already felt really strong for 70 hp, and got 20 mpg with a hole in a piston. If it really improves that much with fresh parts it should be pretty fun.
Off topic, but with all this talk about machining and engines. It's hard not to turn back to the LS community. It's amazing how far manufacturing has come, I know Flossy doesn't have many miles on it. And yet the only correct way to build it is to basically rework every aspect of its construction. Fast forward 50 years of production. I personally know multiple people who have gotten LS engines with well over 200,000 miles. Tear them apart and they say the rings/bearings are still good! And they still have cross hatching. It's just crazy how far the tolerances have come!
Yes you are looking at a few improvements that have made dramatic differences in how long engines last. As I have beat to death in the prior posts, the machining of the engine is critical and it has come a long, long way. The surface finish of the bore, and fit of the pistons in the bore are one of the primary reasons they do so well. Excellent new gasket technology and super accurate and precise CNC machining of sealing surfaces, have changed a lot of things. Computer control, controlling fuel wash at start up and while running added tremendous durability. What we have learned from decades of racing and pushing components have really made a difference. I have "cammed up" and stuck a great set of heads on a stock LS6 with over 100,000 miles on it and made 500 hp! The key was as we spoke of, the leak down was excellent. The engine was carrying good oil pressure. The oil was staying clean. The wearing of the rings and valve seal, begins as the sealing of combustion is lost. New materials, precise machining and cylinder wall finish as well as piston ring technology, has pushed modern engines way past what we were used to. At 50,000 miles in 1965, it needed a valve job, the rings and cylinders never made it past 100,000. They leaked all over. The better they seal everywhere, the longer they last.
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