Is the valve lash adjustable on those Tecumseh's like the old K Series Kohlers were?
Looks like a Tecumseh flattie.
Yeah I know that's why I was asking. He mentioned checking the valve lash so I was curious if it was adjustable like the K Series flatheads were. They had adjustable tappets which is pretty handy.
no there not adjustable, you have to pull the valve and grind it down to spec, i just did my 10hp snowblower tonight made a big difference
MightyRaze Administrator
Age : 45 Join date : 2016-09-06 Posts : 6964 Forum Rep : 520 Location : Central Oklahoma
Does an old Tecumseh have a compression release of sorts?
On the vertical shaft engines, that have the oil pump driven off the cam. When the engine is not running and no oil pressure, that is when the compression release is on. It is on the cam exhaust lobe. The cam is hollow and a pathway for the oil to the whole engine. When the engine is cranking to start, it dumps compression out the exhaust a few revolutions, enough to get the engine spinning and to fire. when the engine fires, usually when the oil pressure is at max, the easy start rod on the cam lobe disengages and you get full compression. If the engine doesn't fire or start then the easy start won't disengage. The oil pump will only supply enough oil to disengage it when running.
On a horizontal shaft Tecumseh, IDK if it has this setup or a different kind of setup. But does need the rpm of engine running to disengage it, and cranking rpm usually isn't fast enough.
Buck Screwdriver
Join date : 2017-11-01 Posts : 266 Forum Rep : 9 Location : Foggy East Coast
I have read something about that before about cranking speed, ill hook up my booster to it and see if it makes a difference. i still need to do the valves you can hear it leaking and i have to pull the head to do it, might aswell clean the ports up and new head gasket
prancstaman Hammer
Join date : 2015-02-02 Posts : 1367 Forum Rep : 85 Location : Cleveland,Ohio
Might work with the booster, get it spinning as fast as you can. Since you are going to pull the head, best time to check to see if it has the easy start on it. By seeing if the exhaust valve will spin on the compression stroke (the whole stroke), and the intake stroke (the whole stroke) for a comparison. If the valve spins any on the compression stroke then you know for sure it has the easy start on it. If it spins on the intake stroke any then you know the valve is out of adjustment. The valve should not spin by hand if seated correctly on the seat. Basically putting finger on the edge of the valve and trying to spin it for the test.
MightyRaze Administrator
Age : 45 Join date : 2016-09-06 Posts : 6964 Forum Rep : 520 Location : Central Oklahoma
Good information prancstaman. I didn't realize those older engines were that complex.
Thanks. The Tecumseh engines had the pressure lube on the vertical shaft engines, I started noticing that on the 80's and late 70's engines, when Briggs was using the oil flingers on theirs. But I see alot of down talking on the Tecumseh motors though, even though mostly everything else is the same except how they balance the crankshaft. I'd rather have a Tecumseh then a Briggs. Torque motors they are.
Crazy_Carl BoogerWeld
Age : 31 Join date : 2017-10-30 Posts : 2328 Forum Rep : 145 Location : Rochester, New York
Subject: Re: 73 sears workhorse/mudder Tue Mar 20, 2018 9:17 am
@prancstaman Man you have so much good engine knowledge hidden away in that brain of yours. Don't be surprised if I contact you for engine help one day.
@Buck Mault Thank you for keeping your ole tecumseh alive and not running to princess auto to buy a clone motor on sale. I think a good ole tractor with a good ole motor is just awesome.
Contrary to what my signature says I really like your sears. I like following your detailed build thread about it. In many ways your 73 sears build mirrors my 79 wheel horse build in a few ways: we're running the original engines (believe it or not that's not the original engine in Ol Red, but a direct replacement someone put in a long time ago), we use our tractors for work and play, our body work is pretty close to original, we upgraded the lighting, we've re-wired our tractors (isn't it nice knowing where every wire goes to?), we've upgraded the tie rods, we put on a better set of tires, and both tractors are just plain built great right from the factory.
In a couple of ways your tractor is better. You have a front bumper and a skidplate. I have front bumper plans and I've thought about building a nice lower belt guard/skid plate, but lately I'm trying to focus on my build off tractor.
Good information prancstaman. I didn't realize those older engines were that complex.
Thanks. The Tecumseh engines had the pressure lube on the vertical shaft engines, I started noticing that on the 80's and late 70's engines, when Briggs was using the oil flingers on theirs. But I see alot of down talking on the Tecumseh motors though, even though mostly everything else is the same except how they balance the crankshaft. I'd rather have a Tecumseh then a Briggs. Torque motors they are.
Thank you for the info, thats one of the things i like about the group Cheers
@Crazy_Carl, thanks alot man. That was my plan for this tractor was to keep it close to origanal, everything bolt on so i can use implements with it, but change out the weak points, this engine will get a rebuild at some point. for a pulley swap i would like a little more speed in hi so i was going to a 6" on the rear and a 5" on the engine, i want to keep the rear pulley as big as possible so i have more surface area for the belt( less slippage)
the Biggest things i need to do is get better tires for the rear, maybe lock it, fix the front grill, better foot throttle. and then a full paint job.
i like how yours is Turned out as well, I like to keep one close to original. but the other sears is not going to stay original lol I hope one day I find a 79 Wheel horse.
Buck Screwdriver
Join date : 2017-11-01 Posts : 266 Forum Rep : 9 Location : Foggy East Coast
@Crazy_Carl that is not always a good thing lol, i usally never ham on it only in high gear, i use too offroad alot building, breaking , fixing, repeat. i like to crawl but want speed if needed
Buck Screwdriver
Join date : 2017-11-01 Posts : 266 Forum Rep : 9 Location : Foggy East Coast
Subject: Re: 73 sears workhorse/mudder Wed Mar 21, 2018 11:46 am
Double W Cross Ranch DimeWeld
Age : 17 Join date : 2017-06-09 Posts : 2601 Forum Rep : 89 Location : Literally Nowhere, Texas
Subject: Re: 73 sears workhorse/mudder Wed Mar 21, 2018 11:47 am
Ooh that looks awesome! I'm jelly....
Buck Screwdriver
Join date : 2017-11-01 Posts : 266 Forum Rep : 9 Location : Foggy East Coast
When I got Frankin Sears a blade came with it, no mounts, and in great shape just like the tractor lol, i build a mount for it, made it so it can hook into the factory rear deck mount. i dont have a winch yet so its a strong arm lift. and its a workout. [url=https://servimg.com/view/19809240/61 [/url]
AllisKidD21 Moderator
Age : 22 Join date : 2016-07-10 Posts : 5083 Forum Rep : 266 Location : Ontario Canada
Nice blade mounts! So is that big pole on the right hand side of the tractor for extra leverage? I've been wondering about that, haha.
_______________________________________________ "This'll either wake you up or put you to sleep forever!"- Red Green "Whatever you do you should do right, even if it's something wrong." - Hank Hill
When I got Frankin Sears a blade came with it, no mounts, and in great shape just like the tractor lol, i build a mount for it, made it so it can hook into the factory rear deck mount. i dont have a winch yet so its a strong arm lift. and its a workout.
Sears blade is a arm workout too. Bottom 1/4 flat stock is a necessary upgrade should you find one. Yours may be sturdier.
_______________________________________________ Li'l RED my original modified tractor!