Next hacksaw project, Early engine replica

[mr.modified]

I've decided the junk 8hp briggs flathead I bought is in pretty bad shape and probably not worth trying to find a crank and rod for it. Cracks in both sides of the block, bent exhaust valve, ruined crank/rod, nicked up intake cam lobe... So I'm going to use it for my exposed crank project I've been thinking about for a while. First I pretty much just hacksawed the bottom of the engine off, leaving four bolt holes to hold the side cover on. The engine will sit on it's side when finished, as it is in the pictures. I'll have to make up a mount of some kind and bolt it to the engine. Cyl. lubrication will be dripped through a hole in the side of the cyl, probably between the valve springs. I think i'm going to remove the oil ring since it will no longer serve a purpose. Rod will have a grease cup threaded into it somewhere. I'll clean up the rod and crank as they are scored up somewhat. I'll drill a hole through the rod where the wrist pin is so I can oil that. Not sure about the crank bearing/bushing on the flywheel side. That might be tough to get to with the flywheel in the way. The output side rides in a ball bearing, so I'll just oil that and it should go forever. I don't want to use modern looking grease fittings on anything. As for the valves and cam, I'm going to use much lighter valve springs. I may make a wick that rides on the lobes to keep them oiled up. Since the exaust valve is bent and the intake and exaust valves are the same size, I may use the intake valve for the exhaust and use a tecumseh valve I have that fits the intake seat but is shorter and won't reach the lifter. Then I would use a very light spring on the intake valve without a lifter, the suction of the engine pulling the valve open, as was common on many early engines. Maybe I can bend the exhaust valve back enough to use it. I'm going to use two head gaskets together to lower the compression and take some load off of everything. I think I'll use the stock intake with a 5hp tecumseh carb. I might eventually try making my own carb for it. With everything detuned and running at real low rpm's, everything should hold together pretty good. Eventually it would be nice to built a 1/4 scale curved dash oldsmobile or similar early automobile to put this in, but i'll just see if I can get the motor running first. There's some pics of the engine before and after, and also, my new briggs crank case snack bowl. I'll clean up around where I made the cut so it looks a little better.

 

[Motra]

You're crazy, dude! But I gotta hand it to you, you like to experiment and have fun doing it.

 

[rocker92]

You're crazy, dude! But I gotta hand it to you, you like to experiment and have fun doing it.

not all that crazy, this is how some of the first engines were set up, and not to mention that hit-and-miss engines used this system for the better part of 50 years.


cool project! hope it comes along well!

 

[mr.modified]

I've eliminated the theaded holes and sides of where the valve springs are, I was planning on having the springs exposed and it wouldn't look too good to have that smooth machined surface and threaded holes there. It's got to look like it was made in a shed in someones back yard back in 1901. Now with the edges kind of rough, It'll give it a cast iron look once I paint the block black.

 

[Confused1985]

Awesome! Sounds like a great project.
If u want old style grease cups, it might b worth looking for model engineering parts, like the miniature steam trains. A lot of them arnt that small and might have grease cups that look to scale with an 8hp block.
Like Rocker said about hit an miss engines. Might b a way to go if u have a bent valve. I dnt no a huge amount about them other than they only have an exhaust valve. There is a guy on YouTube that did a couple of videos converting a Briggs to hit and miss. Havnt seen all of them so dnt no if the engine worked.
Gd luck!

 

[mr.modified]

Here's some before and after shots of the side cover.

 

[Motra]

It might not be a bad idea to lower the compression and use a big flywheel. That way you could get the RPM down low like an old engine and put less stress on the parts.

 

[mr.modified]

If u want old style grease cups, it might b worth looking for model engineering parts, like the miniature steam trains. A lot of them arnt that small and might have grease cups that look to scale with an 8hp block.

I might be able to find some at an antique engine show I go to. I'll need at least one for the rod. I'm not sure how i'll oil the flywheel side main bearing. One of those glass drip oilers would look good for cyl. oil, but I may just make something up myself.

 

[metal man]

mr.modified if your going to use grease cups on the mains you could pull some off older furnace fans they have a turn down type on them and there old looking . i have seen a few around on other old tooling too

and i have to agree You're crazy, dude!:thumbsup::laugh: but then i have some little idea starting to take shape ...... or well pile o parts more like it :doah:.
maybe when we get them done we should race ?

 

[Confused1985]

For the FW side, you could drill a hole similar to a point push rod, and run a thin gauge copper tube up to the top clear of the FW and mount a grease cup/oil dribbler. The copper tube could be moulded to fit tight to the block behind the FW

 

[Ibanez616]

What a cool project. I hope you can get it running. :thumbsup:

 

[Clayon]

Mr. Modified your insane porjects and hack jobs are so cool and give me an extra urge to come on this forum everyday to check your progress. I can't wait to see the finished result, hopefully it is more than a pile of parts :laugh: but I am sure you can make it work. :thumbsup:

 

[mr.modified]

I hope I can make everything work too... I don't think that getting the engine running itself is going to be too big of a deal, but i've been thinking of how I am going to make a mount for this thing. The aluminum is kind of fragile where it is thin (Like where I cut the block in half). I'll have to make a sort of cradle to hold the block, then I might need to help hold the front on a few of the head bolts. It's not like it's going to tear it self loose just putting along at low rpm's, so it should be ok. Tonight I JB welded up the cracks in the block. Not that I needed to, but mostly just for looks. I also painted the side cover. I'm painting everything gloss black. I've also been thinking of how to make some sort of shroud for the flywheel or if I should try to use part of the old one. I don't need that much cooling, but at least a little air movement over the fins would be nice. I'm definately going to get rid of the pull starter, looks too modern. I was planning on making some sort of hand crank starter for it. I'll get the engine mostly back together first, then i'll see what happens.

and i have to agree You're crazy, dude!:thumbsup::laugh: but then i have some little idea starting to take shape ...... or well pile o parts more like it :doah:.
maybe when we get them done we should race ?

I challenge you to a cross country endurance race.... What kind of project did you have in mind?

 

[metal man]

well ... there is a few ideas like a motor built from pipe and a 1906 bill (copy) powered mini if i can figure out how make work . bad part no mill or lathe so kinda slows stuff down in how to fit things .
cross country endurance race.... i dont know about that . if i can make a lap around town i would consider myself lucky .

 

[mr.modified]

I guess my hacked up 8 horse wouldn't make it that far either. I was also going to try making an engine out of pipe, but never got back to it. I don't have a lathe either and the only thing I figured I couldn't make too good was the piston. I was going to use a scored up 2" bore piston from an old briggs 5s. For the crank I thought I could use some sections out of a car strut. I don't know how I would keep everything lined up to weld it. Then I was going to make a mini engine out of a drum brake wheel cyl, but I haven't gotten back to that either...

 

[mr.modified]

Got the block patched up and painted. I might use the engine to power the soda can crusher i'm working on. I'll have some pics tommorrow afternoon hopefully.

 

[mr.modified]

Got the block painted and drilled oil hole for the valve stems and cyl. I put the old intake valve in the exhaust port and used a spring from a 3.5hp briggs vertical shaft. It's a little small for the retainer but I think it'll stay put. I'm going to make my own spring for the intake since I don't have anything light enough for vaccum to pull it open.

 

[jeep2003]

very intresting! at first i thought you were just making a cutaway display engine then i realized your going to make it run! lol I think i have a bunch or old little oil cups and things somewhere ill have to look

 

[BriggsBoy]

I made one similar to this from an old 3.5HP lawnmower engine. It's still burried in my shop somewhere, just needs a carb. Can't wait to see this one going!

 

[mr.modified]

I got the piston and rod installed. I tried a pretty light spring I had for the intake but it's too heavy. I tried heating it with a propane torch but it didn't help. I've got a lighter one i'll try tonight. I needed a retainer for the tecumseh intake valve I'm using and got one off of a tecumseh vertical shaft engine I saved off a junk ride on mower. Here's what the replica engine might be powering when it's done. My soda can crusher i've been working on. It was geared up way too high, but I'm fixing that as we speak with a bigger pulley from tractor supply. In the video i'm running it with a 1952 planet jr. walk behind cultivator. It's got a briggs model 5s on it. I'll get the enigne ready to go, then i'll make a base for it. It's going to hold in four places. The two lower head bolts and two holes I drilled through the bottom of the block.

http://www.youtube.com/watch?v=0Lr83QKlqz4