@@hitop2365 I'm not sure how this is lubricated, but a Regular Briggs just uses splash lubrication. If he isn't getting any oil up in the cylinders, the metals are going to gall like crazy - which I am just guessing is the case here.
@@taofledermaus Funny/ nice seeing you here man. Internet is a funny place. Back in the day the only people that would know about a guy's crazy project like this (or your projects for that matter), would be his neighbors. Nowadays random schmucks like us can check out someone's work despite living thousands of miles away. Sure beats the other garbage that the internet is often used for! Have a good day.
That is quite a hobby project you have there. Looks to me, if you got this far, surely you will make it work. Trial and error is an engineers best friend.
My very first thought when I saw it running was. needs cooling or it will gauld a piston. you might hone the back cylinders and give a little more clearance may help because cooling the rear will be hard. possibly add some piston oil sprayers to help along with an oil cooler
The issue your having is the cylinders you are using are intended to be air cooled,they can't be that close together.you are going to need a shroud around them to concentrate the air flow in-between the cylinders.also if you are using water to cool them you need more volume in the radiator for the way you have it set up.try building a shroud to concentrate air flow in-between the cylinders first the larger radiator if that doesn't fix it,if the shroud is designed correctly that will work.copy the lawnmowers shroud and duplicate it.
This video was published a year ago and a lot has happend since then. This problem was caused by a flooding carburettor that filled the first cylinder with petrol. (the tractor was jacked up in the rear). When I should start it I had ignition-problems so I ran it a lot on the starter motor. When it fired up the front cylinder was washed cleen of oil and seesed after 10 sec. So it was not a heating problem. However. I tried some fans and a shroud but the casting of the cylinders are designed for an airflow sidways. Not downwards. If I blow the air sideways the first cylinder will be happy but not the last. So. If you look forward in the playlist you can see that it has now become watercooled. I'm not quite finished but close to a first start.
Very cool way having the intake port go down the side of the cylinder like that as long as the intake charge temp doesn't get to high. The crank shaft must be a work of art, such a cool build, those motors make gobs of torque being a single slug. Being a v8 unreal.
I think I would add a fan and some cowling to ensure even air flow as all good multi cylinder inline motors seem to use them, the galling near the pin bosses would seem to be relative to greatest mass area of piston and the proximity of other cylinders restricting air flow !
I'm wondering if the engine failure isn't a result of the imbalances caused by the flat plane crankshaft layout. It could be useful to retrofit a harmonic balancer from another engine to help with this issue or you could machine a crossplane crankshaft.
heat sizing on the exhaust side., Needs more air flow. Fab some deflectors that force the air around the back of the cylinders. And not let it just free flow between them. These are common seen on VW and Chevy Corvairs...
@@Desmouffe nice! i have mounted a 1cyl chinese diesel on my tractor but i cant find any info about the brand of the frame (FABE) you can see it on my channel (i also am swedish ;) i put a turbo on it and well its making the right noises but i think i need more fuel so gonna make spacers for a injector that is double the size and maybe it will finally get way more pover and maybe even more boost? :)
@@Coinfindr propane injection is a good way to increase fuel on a diesel with limited pump upgradeability. Adjustable BBQ regulator and a explosion proof solenoid.
I think I have it under control. A flooding carburetor when the tractor was jacked up in the rear. Petrol ran in to the front cylinders. Washed clean from oil.
I've serviced many Briggs engines over the years in the U.S. and the cylinders you're using look a bit different from the most recent castings I've seen here. Are those bores aluminum or are they hard metal? Perhaps your base engines are units from many years ago, perhaps from the days when they used contact breakers? Maybe some kind of oil squirters under the pistons is in order due to splash not being adequate for good oiling in your application. BTW, I once had a Tecumseh mower engine lock up just pulling the starter rope after a season of sitting, aluminum bore, snagged sharp edge of a ring. Tecumseh no longer in production and parts are very expensive.
I have used mostly 92902, aluminium bore, no contact breakers. Since I've used the pushrod as well I wanted the ones with 25mm creankpin. On newer engines it's 22mm. And 65mm bore. The crankshaft is a bit over the oil-level so my solution is an oil-channel that runs on top of the crankcase and squirts oil down on the crankpins and then being thrown up in the cylinders. When I take it apart all parts seem to be well lubricated. I think B&S are fantastic engines. They work many hours with often a minimum of service. Many engines I have taken apart had almost no oil and it was thick and black. And cylinders look almost new.
@@Desmouffe Thanks..! I agree, have two thirty year old mowers with B&S engines that are still going strong though were abandoned for some simple reason by their original owners.
It is too bad that it ate a cylinder and piston, and perhaps a con rod. Maybe there is an oiling problem with that cylinder. Cooling will also be needed for more than a 2 minute run or so.
I agree with the cooling, but the conrod was a bit tight already from start. I thought it would be alright after running a minute or two, but it got worse. The cylinder I blame the flooding carburetor. I will also use a slightly thinner oil. W50 will be W10-40. I was afraid that the oilpressure would be to low but it was the opposite.
@@ziggassedup I see what you mean. This problem happened after 10 to 15 seconds after the engine started. The front cylinders were washed cleen from oil because of a flooding carburetor. And the reason for flooding is fixed so I think it should be OK .
No. This happend only after 10-15 seconds. The carburetor flooded and petrol got in to the two front cylinders. All fixed... I don't think the fan will help any of the cylinders. I use it as a flywheel and alternator magnets.
@@tioobs I don't. I will in the future but right now I want access to all parts and not hide them under a shroud. Only run it a couple of minutes each time.
It was quite severe damage but also an oversize piston is heavyer and cost money. An old lawnmower I can get for free. I'm not sure my machining skills and equipment is enough to do the job.
You don't have any cooling. Yeah I know a big fan would be dangerous. But you're going to need something. Those cylinders are just packed too close together. That's why briggs engines have big cooling blowers.
It's hard to understand that an INTELLIGENT CRAFTSMAN THAT YOU ARE,,,, DIDN'T THINK IT NEEDED SOME KINDA COOLING SYSTEM ON IT!!! IT'S NOT LIKE A MOTORCYCLE WHERE AIR FLOW IS GOOD RIDING DOWN THE ROAD!! JUST FINS THEMSELVES AREN'T ENOUGH WHEN THE CYLINDERS ARE THAT CLOSE TOGETHER!!!! rig up a COOLING SYSTEM!!!
When I started the project the ambition was to, if possible, build an engine that hopefully would start. It was never meant to leave the testbench. Then my friends disposed an old, broken gardentractor on my yard and since then, it has getting a bit out of hand. Thats why the cooling has been neglected.
You seem like a smart man obviously that thing has to have a cowling around and it’s fucking air cooled what do you expect it to do it’s gonna overheat my God you’re that smart you don’t have a cowling over it😊
It will have a shroud in the future but right now I'm working on it and only run it a few minutes. If I can lay my hand on the cylinders they are not to hot.
