Let's make a 4 cylinder flat

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This shows making the cooling fins for the cylinder heads.
I cut the fins for all 4 heads before taking them to the band saw to separate them.
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Truing up the heads after the band saw cuts.
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A good start on 4 cylinder heads.
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Thanks for looking
Ray
 
Not too much done today I made a couple of riser mounting sleds in order to gain some height and more stability.
View attachment 152697
I will probably work on the piston o-rings next and the risers will make that easier.


And the shop had a good cleaning today also.

Thanks for looking
Ray

Hi Ray .
I've seen it a few times, or have I missed it, it seems like you make aluminum cylinders, right ?
 
Yes the cylinders are aluminum with aluminum pistons.
If you are referring to the cylinder liners I have used cast iron liners in most of my other engines. I am experimenting on not using any liners for engines that are air cooled. So far I haven't seen any problems but I don't have many hours on those engines.

Ray
 
I made aluminum cylinders and pistons for a stirling engine, it runs quite well
I have never tried it with an IC engine
If you succeed then it will be a new way.
 
I don't think it is a new way it's more of a lazy way for me. It would not be a good way of building an engine that will see higher RPMs or long run times. I like engines that run slow and idle smoothly with most run times of less than 5 minutes.
The two cylinder engine I just finished has aluminum pistons and cylinders and all my engines use o-rings. I usually have to replace the o-rings after a few runs but after that they hold up well.

Ray
 
But it's a new way for me and I think it will be a easy successful way for newbies
Sometimes just having the engine running is enough
Thank you for sharing.
 
You are so right Minh

I drilled the holes in the cylinder heads for the head bolts, and the intake and exhaust valve guides. I won't drill the spark plug holes or the intersecting intake and exhaust ports until later.
The cylinder heads needed to have 0.200 taken off of one side for a flat surface to mount the cam shaft support brackets.
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And the results.
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I also made up 8 valve guides.
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These guides are made extra long to give the valve stems more stability due to the overhead cam sideways push when opening the valves.

Thanks for looking
Ray
 
8 valves are roughed in and how I how I made them.
Valve stem is cut using the cross slide.
Valve stem 0.125 in diameter.
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The valve face is cut using the compound slide set at 45 degrees.
Valve face 0.250 in diameter.
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I made all the valves the same length and threaded the ends 6-32 for the brass push rods/spring retainers to screw on to.
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Thanks for looking
Ray
 
The intake and exhaust ports are drilled at an angle in order to miss the head bolts. I would like to tell you that I made a special fixture to hold the heads at an exact angle of some degree but I didn't. I used a couple of 1/8" drill bits for support and some 5/16" square stock to get an angle I liked. The degree of angle is not important only that they are all the same and that they intersect the valve guides. I also taped the holes for 1/4 X 28 threads.
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I used a drag knife on the vacuum table to cut the head gaskets. Not a very good picture you can just see the ones that are already cut in the back row.
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I made a plate for the cylinder heads to bolt on to in order to test the valves using shop air.
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I started laping the valves.
Probably one of my least enjoyable jobs.
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Thanks for looking
Ray
 
Made up and threaded 8 lifter/spring retainer pieces for the valves.
I made minor adjustments to the lifters so each cylinder would be inline with the other cylinder on that bank.
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I am tired of laping valves and taking the heads off and on but I do have compression on all four cylinders now.
I added some springs and here it is.
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Cam shaft brackets are next.
Thanks for looking
Ray
 
I don't think it is a new way it's more of a lazy way for me. It would not be a good way of building an engine that will see higher RPMs or long run times. I like engines that run slow and idle smoothly with most run times of less than 5 minutes.
The two cylinder engine I just finished has aluminum pistons and cylinders and all my engines use o-rings. I usually have to replace the o-rings after a few runs but after that they hold up well.

Ray
Briggs and Stratton has been building engines with aluminium bores and pistons for decades. They chrome plate the pistons to prevent seizure under load.
 
I'm about to make cylinders for my inline engine. There is one caveat with making cylinders from aluminum. If you use any kind of lubrication at all, the cylinder will never stop leaking an ugly black sludge that is mostly lubricant mixed with very fine particles of aluminum from the inside of the cylinders as they wear away. Cast iron has a high graphite content in it's make up, and that graphite provides a lot of the lubrication. Most people I know use either an all cast iron cylinder, or an aluminum cylinder with a cast iron liner. High revving engines use an aluminum piston, slow revving engines use a cast iron piston.
 
I have been working on the wood base for the engine the last couple of days.
Just put the final coat of poly on but at 50 degrees in the shop I'm not sure how good it will cure.
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In between times I have cutout, drilled, and installed set screws for the 8 cams.
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Thanks for looking
Ray
 
No never had a Subaru or a Volkswagen .
Thanks for asking Streatch.



The poly finish on the engine base cured very nicely over night so I mounted the engine. It wasn't as easy as it should have been if I had drilled the riser holes in the right place. They needed to be 1/4" further out each way to miss the engine side bolts. I did the same thing on the flat twin engine too so I had to get a little creative.
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I was able to make up the timing belt rollers and tensioner arms.
This is the flywheel side.
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And on the rear of the engine.
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I have not adjusted the cam timing yet but everything turns like it should. (happy day)

Thanks for looking.
Ray
 
I went out to the shop this morning to work on the engine some more when I realized I didn't have any materials for the intake or the exhaust systems. The parts are on order now.

One of the reasons I wanted to make a 4 cylinder engine was I wanted to use a distributor. I made a prototype to test my ideas and was going to start on a model when I found this for a very reasonable price I couldn't pass up.
Dist.jpg

It is a self contained unit of 4 magnets, a hall sensor, a rotor, and a dist cap. All you need is an ignition module, some spark plugs and some batteries to make it complete. It took a month to get here from China but when it did I just couldn't put it aside for later I had to test it.
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It works great but the spark plug wires are too short for my engine. I did find some 10,000 volt ignition wire of the same size that will be here next week and then I can replace the short wires.

The dist is mounted on the left bank's cam shaft using a flexible coupling and a rigid bracket attached to the cam bracket. That way when adjusting the cam bracket everything will stay in alignment. The ignition timing is adjustable by loosening the clamp screw and turning the dist.
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If this works out it will be a very neat , easy and compact ignition system.

Thanks for looking
Ray
 
Well I had one of those days.
I wanted to make eight 0.250 diameter X 0.750 long brass nipples for the intake and exhaust ports. There is a 1/4X 28 thread on one end 0.500 long and a 3/16" through hole.
Doesn't seem too hard right.
I ended up making 12 bushings before I got 8 that were good enough to keep so I took a picture of each one of them.
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Sure glad that's over.

Thanks for looking
Ray
 

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