Need Help With Tecumseh 3.5hp

[tenlizard]

ok i cleaned the carb and fixed it, cleaned the head, gasket, valves and piston. finally i got it running great. then i forgot that i took the oil out and it ran, then it smoked an siezed. i took the compression and it said 25psi before it was at 75psi. i tried to start the engine but it wouldn't start again. i took the rings off the piston and put them in the cylinder...the gap with the rings wouldn't touch they were missing by like .10 of an inch. i don't know if it was the cylinder that got worn down or the rings worn down...how can i tell...i looked for repair parts on the tecumseh website and they didn't have new rings and i am pissed PLEASE HELP! It won't start because of the too low compression.

 

[Kenny_McCormic]

Is the bore scored? You could bore it out for a bigger piston but its more economical to use it for an anchor.

 

[tenlizard]

the bore is scratched a little. but not enough to make the pressure go to zilch. i took the engine apart and put it back together and tried starting it with 5 pulls. the piston got stuck or something. i noticed that the flywheel was hard to move even with the spark plug out, and the crankcase open. i think that the bushing under the flywheel for the crankshaft is damaged or needs to be re-oiled or something. also i think the reason for the compression issue is that the valve seats have cracked or something. i opened the spring case and when the valves are seated, there is a space between the lifter stem and the retainer. i know this is incorrect. so basically, the bushing needs to be re-oiled and the valve seats may have popped out but most likely cracked. how can i repair valve seats or will i have to order new ones? i'm not even sure what valve seats look like if they are attached to the block or if they are seperate pieces. i had to use all of my strength to make the flywheel even budge. i poured oil down the cylinder to the piston and nothing leaked so i think that the rings and cylinder is fine. it has to do with the valves for the compression issue and has to do with the bushing with the hard turning. the bushing i'm probably going to replace.

 

[jr dragster T]

Hope you have a boat cause you have a nice new anchor for it!

 

[Kenny_McCormic]

What he said, salvage the recoil/cooling tins, carb if its the adjustable variety, ignition system and maybe the exhaust, then knock a couple holes in the block and tie a rope to it.

 

[tenlizard]

so there is no way to fix it?

 

[jr dragster T]

Well there is but its pretty damaged.

 

[Kenny_McCormic]

You could probably rebuild but it will cost more than a good condition used motor(you could **** near buy a clone), scrap it out and use the rest for a boat anchor.

 

[jr dragster T]

Lol I'd just red nek it so it runs kinda and just run nitro through it and give it a shot of nitrous. Cause realy if your gona blow it up do it right.

 

[go kart mozart]

paper weight

 

[tenlizard]

ok i just went into my engine further...i used a leveler on the valves because they looked bent a little...i measured them out and whoopdedoo! they were bent not allowing for the valve to rest on the seat completely letting the compressed air/fuel mixture out of the carburetor and exhaust on the compression stroke. the exhaust valve was bent the most and the intake was a little. they were bent because of overheating. haha i figured it out! no boat anchor now. the bushing still needs to be replaced.

 

[Kenny_McCormic]

What bushing? the crank bushing? Crank is probably screwed as well if its froze up, just sand both a lil so it turns free.

 

[tenlizard]

yea it freezes sometimes. was playing with it today and it's putting its usual resistance again. i'll sand both of them and oil them anyway. hopefully i can get her running again! i still don't like tecumsehs i like briggs flatheads!

 

[tenlizard]

i can't get my stupid flywheel to come off. i got the nut off and the starter cup and such. it should slide right off but it isn't because it hasn't come off in 20 years! i'm having a hard time getting it off. i'm trying to pry it off with screwdrivers while hitting the end of the crankshaft with a hammer but it still won't come off. the ignition is breaker type (pre-historic) could this have anything to do with it?

 

[Kenny_McCormic]

Be careful not to damage ignition system, A prybar and a sharp tap from a deadblow always popped em off for me, even on 50year old tecs that have never been ran.

 

[tenlizard]

this has a big flywheel and there is no place for me to convert my engine to use a coil. there aren't even mounting bolts. all the ignition is behind it! is there any way i can convert it possibly?

 

[tenlizard]

what exactly should i do to get the flywheel off?

 

[Kenny_McCormic]

Points are great, especially the point systems on the old tecs with behind flywheel ignition. Never seen one have a problem, very reliable. Pry gently and smack it with a deadblow hammer.

 

[I like karts]

I would just try and take everything out and OIL THE CRAP OUT OF THAT THING. I mean soak every internal part so it spins nice and smooth. then try again.

 

[Russ2251]

i can't get my stupid flywheel to come off. i got the nut off and the starter cup and such. it should slide right off but it isn't because it hasn't come off in 20 years! i'm having a hard time getting it off. i'm trying to pry it off with screwdrivers while hitting the end of the crankshaft with a hammer but it still won't come off. the ignition is breaker type (pre-historic) could this have anything to do with it?

Flywheels are inanimate objects and therefore have no intelligence ("stupid flywheel"). They never slide right off. Shaft and flywheel are tapered so as to lock them together with key. I use a piece of 2x4 and a dead blow mallet.
Prying almost never works without damaging something.
If done correctly, can be removed in seconds with zero damage.
Use a torque wrench when re-assembling and don't use any lubricants or it will likely have to come apart again.