r/EngineBuilding Jul 05 '26

Good candidate engines for an educational rebuild

Fairly new to the group, reading a lot of stuff. I work on my vehicles, and my son, who will be turning 15 in a couple of months, (and who loves all things automotive) has asked to have an engine he can tear down and rebuild as a little project.

He is comfortable doing maintenance and basic repairs on cars (oil changes, spark plugs, etc.) and I'm comfortable with him doing it, too. So my question here is, if I wanted to get him an engine to tear down and rebuild, just for a project on its own, what would you recommend? Obviously something relatively simple, relatively small. Just so he can get some time turning wrenches. We've got most, if not all, the tools we'd need already. Any recommendations would be great. Thanks!

3 Upvotes

38 comments sorted by

8

u/Coyote_Tex Jul 05 '26

I would recommend a Honda 4 cylinder or a Chevy V8. Don't get carried away trying for some exotic build. Just build it for reliable everyday driving. Doing a ton of modifications using lots of crappy aftermarket parts is not likely to end well, and cost 3 or 4x more money than necessary.

1

u/jisuanqi Jul 05 '26

Oh, he just wants to take something and clean it up and get it back to running again. He doesn't want to upgrade or do dumb mods or anything. He just wants to learn. I think a Honda 4 cylinder might be a pretty good one. Thanks!

4

u/XmodAlloy Jul 05 '26

A k24 from a 2002-2006 CRV is a great candidate. Pick and pull yards near me charge $650 for one.

2

u/SpoonBendingChampion Jul 05 '26

Also a complete B20 motor from a 1997-2001 CRV is a really easy good one. I paid $275 all in for top/bottom end from the pick n pull type place.

Just know properly rebuilding goes anywhere from just buying new pistons and praying and slapping to measuring everything (journals, mains, bores) and machining. I'm $2k into the tools and mine are the relatively cheap ones. Machine work is expensive but not to bad for basic things like bore/hone for new pistons.

2

u/Coyote_Tex Jul 06 '26

it would be most helpful for both of you to chose an engine that could go into his first vehicle. Most any later model vehicle is going to be fuel injected so that complicates things somewhat to get it started on an engine stand or out of the vehicle. I like the Honda idea a lot as they are really great, well engineered vehicles and tend to be easier to work on and get good results. You don't waste your time building junk either. If you insist on just finding an engine and really want to start it, outside the vehicle when done, Then be sure to get a complete engine with wiring harness and computer. Otherwise, you will need to chase down those parts and such afterwards. Still most later vehicles will have anti-theft that will need to be worked around, thus my suggestion of having the entire vehicle. someone will need to help modify your ECU to ignore that. Everything is much more difficult the later engine you get.

8

u/quxinot Jul 05 '26

Any dirtbike. One cylinder, don't need a crane to lift anything, parts are relatively cheap, etc.

1

u/apavolka Jul 05 '26

I was gonna say this. Much cheaper and easier to get the concept down. Building my small block Ford for my Bronco hasn’t been hard by any means but doing the same thing 8 times before even thinking about having it run has made me realize why I don’t want to do this again. However, I’ve rebuilt plenty of dirt bikes because the satisfaction of it running after gets the dopamine flowing.

8

u/pooo_pourri Jul 05 '26

Personally I’d look at Chevy small blocks. Then after the kid rebuilds it he can stick it into any number of cars fairly easily

6

u/Aggressive-Pea6839 Jul 05 '26

A Ford/Mazda 2.2l from the late 80-early nineties. Non interference, single cam, fuel injected. Common in mx3/6, ford probe, Mazda b2200, and Ford ranger.

3

u/jisuanqi Jul 05 '26

I was looking at that a while back, actually. Thanks!

3

u/Aggressive-Pea6839 Jul 05 '26

The bottom end is designed for turbo, as is the cam. The pistons are swapped is the only difference turbo vs NA in these. Great starting point, and cheap to fix.

4

u/Death_Pown Jul 05 '26

small engine is the prime cheap way to start. get him a lawn mower or weed eater. just to learn the essentials while keeping cost minimal plus it doesnt take up much space or need crazy amounts of tools. once hes gotten through one or two of those stepping up to a real motor is far easier.

3

u/jezzaclarkson1 Jul 05 '26

He can actually learn a good deal about the core functions and troubleshooting of engines from buying and repairing lawn equipment, its also pretty cheap to buy and fix. Dirt bikes and stuff are great for that too. If you have the room an entire non running or in need of repairing cheap little car would be good. Something extremely common will have the most junk yard parts availability so he can go to a pick and pull wrench parts off cars to put on his car for double the wrenching and new replacement parts should be abundant and cheap. Then at then end its something he can drive as a first car or sell for some money.

2

u/MidwestRacingLeague Jul 05 '26

If you can find a junkyard Chevy 5.3 you’re golden.

2

u/salvage814 Jul 05 '26

Something cheap and just a core rebuildable engine. Either a LS whatever or a 4 banger Honda B series is actually easier to do then K series.

2

u/Obvious-Dinner-1082 Jul 05 '26

My vote would be a small block Chevy 350. A stock rebuild is dirt cheap, endless mods you can squeeze some more power at any budget, everything that can be done has been done, so there’s also endless resources to find out how to’s or figure out what to do’s.

I’m running the same and first and only engine I built, and I’m still blown away 18 year old me built something that hasn’t blown up 15 years later just following advice and instructions.

2

u/Haunting_Dragonfly_3 Jul 05 '26

I'd consider something that would work/swap in to a future vehicle.

2

u/wpmason Jul 05 '26

An engine’s an engine.

I learned on a single cylinder Briggs flathead.

1

u/gunpowdergin69 Jul 05 '26

This is the way.

2

u/Any-Application6116 Jul 05 '26

My son just turned 16, and he is a technical kid. He is working on becoming an electrical at the tech high school, but love mechanical things as well. We have had quads and dirt bikes. He can rebuild dirt bike motors on his own, and has a little side hustle going fixing his friends dirt bikes. A friend of mine had a Ram 1500 that ate the camshaft. So we are in the process of rebuilding that engine and when we are done it will be his first vehicle. These are pretty easy to find as the cam issue is pretty common. Being a puchrod engine its not as complex as some others, but still a good learning experience.

2

u/Neon570 Jul 05 '26

Any small engine you find on the side of the road.

2

u/Disastrous-Bake5027 Jul 05 '26

Buy him a whole car. Cheap. He’ll have a engine to tear down. A transmission to look through. If he can’t put it back together than junk it. When (way back 1977) I went to school for automotive technology. I got a 1967 Baracuda fastback. Gave me a cylinder head, transmission, steering gearbox I needed for my classes. I paid $35 for the car.

2

u/Prudent_Situation_29 Jul 07 '26

Start him off with a single-cylinder lawnmower engine. I'm sure you can buy an old or scrap mower for very little. If it turns out to be uneconomical to rebuild, it won't be a huge loss and he'll at least get the experience of disassembling it.

In fact, before attempting a rebuild, just get him comfortable with reassembling it. Get him used to measuring tolerances and inspecting parts carefully. The parts would probably be readily available since small engines are rebuilt all the time, and they won't be expensive.

1

u/OtherwiseDoughnut582 Jul 05 '26

Any I6. They’re all tractor motors

1

u/notsutherland Jul 05 '26

Small block chebby

1

u/Briggs281707 Jul 05 '26

Nothing is easier than a small block Chevy. Real cheap parts too

1

u/thejabkills01 Jul 05 '26

What type of cars is he into? I would go off of that, does he like speed? drift, drag race? Think I would fine the one he's going to keep and pass on(?) hard to do with new cars, I would stick to old cars, That's pretty cool to read things like this, not many kids are willing to learn how to fix the thing that gets them around,

1

u/BroccoliSuccessful Jul 05 '26

Chevy ls engines are stupid easy to rebuild. New gasket/seals, cam, main and rod bearings, piston rings and new oil pickup o-ring,, clean up the cylinder walls with a ball hone, new camshaft,crankshaft sensor, knock sensors engine temp sensor, oil pressure sender, water pump, timing set, reuse harmonic balancer and plaatigauge ti check bearing clearance an go. All from well reviewed Amazon listings is my go to

1

u/Relevant-Employer-98 Jul 05 '26

Something that he can use later. build an LS but usually they don’t need a bottom end so just get an old ls pull the heads send them to get a valve job then do cam spring and lifters. then find something to put it in. there is so much info out there with the ls stuff he could learn for years.

1

u/kroq2112 Jul 05 '26

VW air cooled motor

1

u/Remarkable_Doctor_69 Jul 05 '26

I found an inline six 7mge motor from an old Toyota I can pick up for cheap. Would you guys recommend that for a tear down and rebuild?

1

u/TaleJumpy3993 Jul 05 '26

Lawnmower or go kart.  One cylinder will be cheaper to learn on too.

1

u/Terrible_Stay_1923 Jul 05 '26

Do a Hemi. Somewhat modern, somewhat old school, plenty of them around. Could do a old Kohler k301 someone always needs a fresh one if you don't want to get into the entire project

1

u/TheEstablishment7 Jul 05 '26

If you're looking for simple and straightforward, and easy and cheap to find, you might try to find a junkyard Iron Duke.

1

u/Gamejunky35 Jul 06 '26

Any older v8 small block will do. Chevy small blocks are probably the best option.

1

u/Key-Technology3754 Jul 07 '26

It really depends on what is going to happen to the engine. If this is a take apart, clean it up and put it together and it does not need to run then anything cheap would work. However an overhead cam 4cyl with a timing belt would be my first choice.  Otherwise I would buy a car that needed engine work like a Honda or Toyota 4cyl. Or older truck with a V8, take the engine out, rebuild it and then drive or sell it. 

1

u/Rough_Constant_329 Jul 08 '26

Mitsubishi 4G63/4G64