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This is for a Toro pace lawn mower.

I wasn't getting any compression. The intake valve was stuck open. I freed it up and worked it back and forth. I noticed it looks like it is at an angle to the block. The odd thing is that if I rotate the valve, the higher side is always to the left. It is almost like the stem is at an angle and not bent. It lines up with the pin in the access hole. What are your thoughts?

On some engines the valves are not square with the block. Has to do with swirl patterns and other high tech stuff dealing with engine design.

I'm only getting 60 psi compression, and it is still not starting.
The exhaust valve is flush. Do you guys think I should try bending the intake side flush?

I would do a leak down test to see where the compression is leaking out.

Set the valve lash to 0.030" and see what compression you get
In operation the valve is supposed to rotate so bending is not going to be a good idea
The only engines where the valve is square on to the head are side valves

Unfortunately, I don't have a leak down tester. The intake valve protrudes on one side when seated due to it not being parallel to the head.

I've been trying to start it with a drill. Would that affect the compression at all?

What do you guys think I should try next? I'm close to just trashing the mower.

I don't think a battery drill will work, a heavy duty corded drill might.the recoil starter would work

OK. I'll try testing compression again with the pull rope.

Compression gauges are pretty much useless on most of these engines.

Double ditto on Fish's post
If the valve was bent there would be 0 compression and you would get gusts of air blasting back out of the carb
If the valve is bent it will appear to wobble when rotated
The valve has to be square on to the valve seat so it can seal , nothing else matters.

I'd try to relap the valves before doing anything serious. Having the valve sticking open a bit might have messed up the seat to valve contact. Get some lapping compound, probably videos on Youtube on this.

Valve head seat face must always be square to the valve seat in the head.
Don't care what the angle of the valve is in relation to combustion head.
Could the valve seat come loose in the head and it "looks like" the valve is bent ?
You're pictures to me show nothing of the problem.

I was able to get it to kick off or fire once or twice. I wouldn't say that it actually started, however.

Is there a way to put the spring back on without a special tool, if I remove the intake valve?

There is, with me it usually involves a flat head screwdriver, plenty of patience, and some bloody and gouged knuckles. or finger tips
since then i've gotten a Stens 750-174, or similar, you just install the spring with the keeper in the grooves and adjust the holding grooves wider or narrower to hold it tight, but not too tight., and then compress it, then i stick it on the valve with the keeper hole towards me, so that way i just pull the tool straight back and voila!

I noticed the exhaust valve bumps open a little bit on the compression stroke. Is this a compression release mechanism to make it easier to pull start?

What particular tecumseh are you working on, model # ?

bluefitness said:

I noticed the exhaust valve bumps open a little bit on the compression stroke. Is this a compression release mechanism to make it easier to pull start?

Click to expand...

yes

Scrubcadet10 said:

What particular tecumseh are you working on, model # ?

Click to expand...

I'm not sure of the model number for the engine. The Toro model is 20070.

Hold your thumb over the empty plug hole. With the throttle wide open (to let air in), turning the engine full-speed by pull rope or motor should blow your thumb off the port.

Are you supposed to put grease or oil on the intake and exhaust stems, springs, etc.? I noticed the intake stem was difficult to put back in. The exhaust valve was easy. I'm assuming it was because of the intake valve seal.