[23] [unique] Flexible, by Krawler86

You're doing a great man, I'm really enjoying watching this progress!

Aside from VariDrive applications I run 1/2" belts on everything and haven't had an issue yet, I'd only run 5/8" if the situation actually warranted it. I find pulley sizes and clutch location/design plays a bigger role on clutch action than belt width but that's just my experiences.

Thanks for the information and encouragement, I appreciate it.

I have returned the three fhp belts because I have learned they were the wrong line for my application. I spent a bit looking through the Napa belts and hoses catalog and found some 1/2in A belts that were wrapped with polyethylene. They were specced for heavy duty power transmission and able to be used in a clutch application. It seems sturdier and stronger than the fhp belts by a large margin and they were less expensive.






I've also started on the engine mount. Since this is a vertical shaft, I have no horizontal mounts. The now bottom side of the engine isn't even flat or parallel to the crank shaft. I bolted some angle onto the face and used some stuff to set the crankshaft parallel to the fabrication table. Then I welded a piece of 3/16 x 3in flat bar to the bottom as a foot for the engine mount. I'm going to be adding more to it when I get the chassis crossmember installed. It will be what bolts the engine mount to the frame and will replace the original vertical shaft mount. I'll be continuing these things tomorrow morning. I'm going to be feeling really accomplished when I get the engine bolted down and I can actually tension the belt, set up the clutch and start the exhaust and brakes. So many fun parts to design and built still, I love it

Interesting. I know it is pressure lube, so that is good. I am not familiar with that engine. Where is the oil pickup? Is it in the oil turned on its side?

MightyRaze wrote:

Interesting.  I know it is pressure lube, so that is good.  I am not familiar with that engine.  Where is the oil pickup?  Is it in the oil turned on its side?

Unfortunately not. The sump is designed to be the whole bottom section of the block, and when i turned it on its side, the oil pump is about half submerged and the pickup is at the approximate oil level il be running. It would probably survive running on level ground as long as the oil was a bit over full but its no good. Unfortunately i lost thousands of pictures on my phone about a month ago so i dont have my crankcase pictures on hand anymore, but theres a few posted earlier in this thread when i was thinking about how to take care of the oil pickup issue. The only thing stopping me from sticking the crank seal in and gluing the case halves together with RTV is the finalization of the pickup. Its one of those things that i havent solved yet, but im completely confident that i will find a solution so im continuing with the project and will solve it when i get to it.

I ordered the pickup for the CH23 horizontal variant, but the oil pump is oriented differently and it wants to go into the crankcase wall installed in my CV23. Im going to be making my own pickup foot and connecting it to the pump inlet with a steel pipe. I have a few different pipes bent up for a couple different foot locations but i just havent settled on a foot design. It will be bolted down to the floor of the crank case at the lowest point towards the center. After the engine is final mounted, the pickup will be back to a major priority since il want to start tensioning the belt, building choke and throttle linkages, exhaust, air inlet piping, that type of thing and i wont want to get those things going and then have to pull the engine again to finish internal work. I also want to figure out a screen to go around and possibly a small set of baffles in case i get in a crazy angle and the pool moves away from the pickup, or possibly an accumulator in parallel with the pump outlet. I will have an oil pressure gauge as well so i can monitor things while cornering, accelerating and whatnot.


The crossmember im building to mount the engine is pretty simple. Its two pieced of flat bar bolted to the underside of the frame. 8x M8x1.25 bolts and thats it. The narrower of the flat bars is 3/16in thick, and the wider one is 1/8. No particular reason other than thats the scrap i had.






I have also changed to the A69 wrapped heavy duty belt. I was reading a bit more and this belt seems to be polyethylene wrapped and polyethylene fibers for the tension member as well. I found this same belt also polyethylene wrapped but with the tension member made with aramid fibers, (generic kevlar) and im going to buy one for a spare. It should be really strong and not stretch. I remember swapping to an aramid fiber belt in an RC car i had back in the day and it was a game changer and the belt for my tractor is only $21 instead of $16. Im sad the new belt is black though, i really liked the idea of running a green belt.






I dug around and found a couple pictures of my oil pump pickup stuff. It doesnt show what i currently have going on but it can give you an idea. Im using a piece of fairly tightly bent 5/16 fuel tubing from a Toyota 2F that was in the corner. The left side that the end of the tubing is almost touching is the "bottom" of my engine. It will sit slightly tilted back so the pickup will most likely be about 60-70% offset towards the back of the tractor with a little foot and screen mounted to the bottom side.


The stock pickup foot is just a horizontal tube with a screen around it. I want the pickup to come in from the top so the open end is pointing down and i think it would be less likely to suck air.

The issue I’m thinking about with the conversion is less with the oil pump and more with possible oil capacity. On Briggs engines, one of the biggest differences between the vertical and horizontal engines is where there is added oil capacity. The vertical engines have a large sump that the crankshaft goes through, where the horizontal engines will have added capacity at the bottom of the block, and a short side cover where the vertical’s sump would be.

In converting your vertical shaft to horizontal, you are using the small area in what is now the bottom of the block to hold oil, and leaving a big open area in what is now your side cover. I’m interested in seeing if you will have enough oil capacity for safely running the engine.

It may be worth your time to install an oil temperature and pressure gauge to monitor those parameters. I don’t have a pressure gauge on my Briggs opposed twin, but I do know that average oil temperature fluctuates if the oil level is low or high. If my oil temperature drops suspiciously low, it’s usually because I’m low on oil. It’s actually sort of odd as oil plays a part in dispersing heat from this engine. Perhaps with the low oil level the oil absorbs less heat and is leaving it in the block. Interesting tidbit, but your situation may or may not wind up being completely different.

I share all of your concerns RichieRich.  The oil level before the crank starts chopping it all up making windage go insane is lower than when in the vertical orientation.  I've estimated that I'll be able to run just under two quarts because of how fat the cover is, but the oiling is my main concern.  That's why I'm considering running an accumulator in parallel with the pump pressure outlet in case I start pulling air it could make up for it for a handful of seconds.  

I also have already bought this cool little oil filter spacer with two pressure ports available which will be populated with pressure and temperature sensors.  

I've even considered doing something like a full pressure cooler as well for some extra capacity stored externally while running.  

Perhaps if you were good with a tig you could cut a hole in the bottom of the crankcase and weld in a little extra sump you could run your pickup too. Maybe even machine a flat around the hole in the block and bolt on a sump. Still probably asking for trouble though. I could probably guess about how well the block would weld though, and the sump could move your engine and thus COG up some, making it less than ideal.

I bought a derale oil filter relocate kit off of summit to run a cut down nissan power steering cooler on MUTT. This does add some oil capacity, but if the pump is already sucking air I couldn’t see how it would effectively push the extra capacity back into the block. Hard to say though. May depend on which side of the oil pump it winds up on.

Man, if I was confident in my skills to add a lower sump to the engine I would, that's a really cool idea. I could even have it hang down through the cross member and sit between the steering arms and not raise the engine.

That's kind of similar to an idea I had to mount a tank off the side that would be gravity fed from a drain or two in the block and have the pump pickup from the tank.


I worked on the engine mount for a couple hours this morning and decided I didn't like it and cut it all apart. I'm starting from scratch again and have a new plan that should look nicer and be more effective. No pictures yet though, I tend to get working and forget to take pictures, then my coworkers arrive and it's time to start the day. I'll post something this weekend.

I have a small update. I've still been working on this, I just haven't had the motivation to post lately. I'll do a large update soon.
I mocked up the bodywork with the clutch and front tires on. I'm pretty happy with how much of the terrifying sack destroying madness the center console will cover up. I don't really enjoy sheet metal fabrication all that much so I'm glad I'll only have to make a couple small belt guards.


I will post better pictures and more detail later but my clutch is almost fully functional. It operates from a level on the left side down by my foot which will be hooked to my clutch pedal with a linkage eventually. The linkage from the bottom arm to the upper idler carrier is made from two Toyota hood struts. I just cut the shafts off and welded them together. They quickly raise a heavy land cruiser hood and never break so I think they will be strong enough for the clutch. It's tensioned through the linkage so I wanted something strong. The tensioning spring is hooked to the frame and the clutch pedal lever on the left so that if the linkage falls, the clutch will fail open and safe.



Tomorrow I'm finishing some engine mount stuff and I'm not sure what next, probably will go back to the engine oiling problem. I need to finish the pickup foot and get the engine sealed up and final mounted. I really want to run the engine.

Still working just saving up a large update I guess.

Im almost done solving the largest hurdle left in the engine, the oil pump pickup for the horizontal conversion. I made this little guy from a land cruiser power steering banjo fitting. I welded a cap to plug the top and stacked a few tacks on the bottom for feet so it can't seal against the floor. I'll have some kind of clamped union mating it to the pump inlet as well as a bracket to hold it in place attached somewhere to the inside of the engine block. I can't have this little thing moving around or falling off.

That's awesome.  You have enough room to run some kind of L bracket to that screw on the oil pump?  Right of the plastic gear on the base?  Just a thought.