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I finally got the drive belt in place!
Then I had to straighten a bent bracket and add two washers for a pulley to get lined up. Was able to get the motor running, I went for a drive and everything looks, feels and smells like it’s all good!
NOW I’m back to the motor won’t start!
Has my engine jumped out of time?
The motor starts to spin then I guess the spark plug fires, I hear a loud pop and the engine goes backwards. I hit the key and it will be spinning one way, but it’s like when the compression gets into the cylinder the engine turn slowly till it gets past that and then it’ll spin kind of freely till it hits compression again and it will slowly go past that. If the gas fires during compression it moves engine backwards!
Where do I start fixing this problem!
Lloyd

Hello TLoyd,

It helps to have the product label information off of the machine, so we know what engine you have and how to better help you.

Rider engines don't just jump timing or shear a flywheel key.

When it comes to push mowers, they will shear a flywheel key when the blade strikes a hard object and suddenly stops the engine.

From your brief description it sounds like this engine needs the valves adjusted properly. When the valve lash is too wide, the compression release doesn't work efficiently and the engine fights higher than normal compression. This will cause a stop in cranking and reverse rotation issues.

Auto Doc's said:

Hello TLoyd,

It helps to have the product label information off of the machine, so we know what engine you have and how to better help you.

Rider engines don't just jump timing or shear a flywheel key.

When it comes to push mowers, they will shear a flywheel key when the blade strikes a hard object and suddenly stops the engine.

From your brief description it sounds like this engine needs the valves adjusted properly. When the valve lash is too wide, the compression release doesn't work efficiently and the engine fights higher than normal compression. This will cause a stop in cranking and reverse rotation issues.

Click to expand...

I ordered red RTV permagasket and new feeler gauges (old ones got rusted ). As soon as they come in I will check the lash.
I saw a video that (if I remember right) showed, while rotating the engine slowly, where there is supposed to be tiny movement that you'd notice on the rocker arm that would indicate your compression release was still working. Should I also be looking for that when I have the valve cover off?

Hello TLloyd,

Let us know what engine model you are working on. Otherwise, it is all guesswork. Crystal ball is broken and my lucky socks have a hole in them.

Briggs and Stratton? Numbers are stamped into a valve cover.

Kohler? Usually have a product label on the engine fan cover.

Kawasaki? Usually have a product label on the engine fan cover.

TLloyd said:

I ordered red RTV permagasket

Click to expand...

Please think, of the next guy, that has to remove that cover. Use the OEM paper/rubber gasket if at all possible. Or a sealant that doesn't fully harden.

RTV is amateur hour in my book. Red is the wrong color type for oil anyway. Your mower, use what you like.

I agree with slomo,

At the very most I will only use ultra gray very thinly on a good gasket to reseal a valve cover, but not just straight RTV by itself. It takes prying the covers off if you have to readjust valves later.

The biggest problem with RTV is the people who apply too much of it.

That excess comes off inside and ends up in the oiling system and that is never good.

TLloyd said:

I ordered red RTV permagasket and new feeler gauges (old ones got rusted ). As soon as they come in I will check the lash.
I saw a video that (if I remember right) showed, while rotating the engine slowly, where there is supposed to be tiny movement that you'd notice on the rocker arm that would indicate your compression release was still working. Should I also be looking for that when I have the valve cover off?

Click to expand...

The tiny “bump” that you look for to be sure the compression release is working correctly is in fact the whole key to verifying if the compression release mechanism is broken or working on the camshaft. This is how I check when needed.

Don't know how many valve covers I've tried to remove. Globs of RTV all over the engine. End up bending and replacing the valve cover because it's "stuck on Band-Aid brand".

Soon as I see RTV, I think to myself, here we go. The entire mower now has to be gone over and inspected.

Auto Doc's said:

Hello TLloyd,

Let us know what engine model you are working on. Otherwise, it is all guesswork. Crystal ball is broken and my lucky socks have a hole in them.

Briggs and Stratton? Numbers are stamped into a valve cover.

Kohler? Usually have a product label on the engine fan cover.

Kawasaki? Usually have a product label on the engine fan cover.

Click to expand...

B&S 33R877 0033 G1

Auto Doc's said:

I agree with slomo,

At the very most I will only use ultra gray very thinly on a good gasket to reseal a valve cover, but not just straight RTV by itself. It takes prying the covers off if you have to readjust valves later.

The biggest problem with RTV is the people who apply too much of it.

That excess comes off inside and ends up in the oiling system and that is never good.

Click to expand...

You don't have to pry covers off when sealed with RTV; You shear them off. Then you cleanup the mating surfaces by removing the old RTV.

And yes inexperience people use too much RTV. They also don't allow the RTV cure overnight before adding oil and cranking up the engines. RTV will not cure once oil contacts it resulting in early leaks.

I like it when a DIY type uses clear bathtub silicone and then wonders why it still leaks. LOL

StarTech said:

You don't have to pry covers off when sealed with RTV; You shear them off

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I'm all eyes. Please elaborate.

StarTech said:

You don't have to pry covers off when sealed with RTV; You shear them off. Then you cleanup the mating surfaces by removing the old RTV.

And yes inexperience people use too much RTV. They also don't allow the RTV cure overnight before adding oil and cranking up the engines. RTV will not cure once oil contacts it resulting in early leaks.

Click to expand...

Use a heat gun to soften up the RTV. Use a drill with a wire brush to remove the RTV.

Tiger Small Engine said:

Use a heat gun to soften up the RTV. Use a drill with a wire brush to remove the RTV.

Click to expand...

Boy what ever happen to using a backbone razor blade first and then a final clean up some 2" Medium grit Scotch Brite Discs on a die grinder. Much less damaging to the aluminum surface.

slomo said:

I'm all eyes. Please elaborate.

Click to expand...

It removing the screws then using a block of wood up against the broad side of the cover and smacking the wood with a heavy hammer. Might take a few licks but the RTV will shear then the cover can easily be pried off without damaging the cover. Even works on those hard to get off Honda covers.

Its just like applying RTV where you finger tight the screws, let the assembly sit over night without oil added, and then torque to specs. Using this method even those hard to keep from leaking Kohler Courage Single rocker covers stay sealed.

Now Right Stuff is suppose to be faster setting up but I have never try it.

StarTech said:

Even works on those hard to get off Honda covers.

Click to expand...

Those are the worst. I have one of my own I couldn't get off with gentle persuasion. Guess some caveman tactics are in order.

Right stuff is a great sealer that is not too difficult to fight with later, the drawback is that it is expensive.

I use this. Non hardening sealant designed for oil, gas, grease, aviation and automotive. Made for valve cover gaskets and oil pans.

Does not require a jack hammer to remove a valve cover later LOL.

The number 1 version has a faster setting up time.

slomo said:

I use this. Non hardening sealant designed for oil, gas, grease, aviation and automotive. Made for valve cover gaskets and oil pans.

Does not require a jack hammer to remove a valve cover later LOL.

The number 1 version has a faster setting up time.

View attachment 71901

Click to expand...

Auto Doc's said:

Right stuff is a great sealer that is not too difficult to fight with later, the drawback is that it is expensive.

Click to expand...

I use Permatex Right Stuff and have had great results with it.

Tiger Small Engine said:

I use Permatex Right Stuff and have had great results with it.

Click to expand...

Sure but that flavor of juice must be dug off upon removal. With a crime scene clean-up once all the cussing is over LOL. Use what you like.

StarTech said:

Boy what ever happen to using a backbone razor blade first and then a final clean up some 2" Medium grit Scotch Brite Discs on a die grinder. Much less damaging to the aluminum surface.

It removing the screws then using a block of wood up against the broad side of the cover and smacking the wood with a heavy hammer. Might take a few licks but the RTV will shear then the cover can easily be pried off without damaging the cover. Even works on those hard to get off Honda covers.

Its just like applying RTV where you finger tight the screws, let the assembly sit over night without oil added, and then torque to specs. Using this method even those hard to keep from leaking Kohler Courage Single rocker covers stay sealed.

Now Right Stuff is suppose to be faster setting up but I have never try it.

Click to expand...

I have this -

Sealing up your muffler? That RTV requires muscle to remove. Not for me.

Auto Doc's said:

I agree with slomo,

At the very most I will only use ultra gray very thinly on a good gasket to reseal a valve cover, but not just straight RTV by itself. It takes prying the covers off if you have to readjust valves later.

The biggest problem with RTV is the people who apply too much of it.

That excess comes off inside and ends up in the oiling system and that is never good.

Click to expand...

Tons more is not better? But it's the American way.. way over the top!
Happy mowing and be safe!

TLloyd said:

I finally got the drive belt in place!
Then I had to straighten a bent bracket and add two washers for a pulley to get lined up. Was able to get the motor running, I went for a drive and everything looks, feels and smells like it’s all good!
NOW I’m back to the motor won’t start!
Has my engine jumped out of time?
The motor starts to spin then I guess the spark plug fires, I hear a loud pop and the engine goes backwards. I hit the key and it will be spinning one way, but it’s like when the compression gets into the cylinder the engine turn slowly till it gets past that and then it’ll spin kind of freely till it hits compression again and it will slowly go past that. If the gas fires during compression it moves engine backwards!
Where do I start fixing this problem!
Lloyd

Click to expand...

Drain the carburetor bowl after you check for " Fire - Spark" at the spark plug. Starting fluid initially after draining the carb bowl.

Drain the carburetor bowl after you check for " Fire - Spark" at the spark plug. Starting fluid initially after draining the carb bowl.

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Another session of " Let's all give advice to someone who is marginally capable of understanding mechanical things." I swear, all of you must do this for fun.

Not really, cause we been der and done dat! Don't worry about asking, better than breaking something!

RevB said:

Another session of " Let's all give advice to someone who is marginally capable of understanding mechanical things." I swear, all of you must do this for fun.

Click to expand...

Hi RevB,

As the saying goes.... "Hope spring eternal".

How do people learn to be self-sufficient if no one is willing to teach them?

Yes, it can be a lesson in futility at times because some are impatient and searching for instant fixes, but if even one person learns, that is why we do this.

jaxontheweb said:

Drain the carburetor bowl after you check for " Fire - Spark" at the spark plug. Starting fluid initially after draining the carb bowl.

Click to expand...

Thank you for your advice. I can get the mower to crank and run. Sometimes it just is difficult to start and acts like what I see in other peoples YouTube videos on mowers that need the valve lash adjusted. That’s going to be my next effort.

slomo said:

Sealing up your muffler? That RTV requires muscle to remove. Not for me.

Click to expand...

OK, all this about what kind of gasket maker to use is more confusing to me than helpful.
I pulled off the gasket cover and had no trouble removing the Permatex gasket material. That material was red (RTV?) that had been suggested by an MTD tech during a phone conversation that took a considerable time. Sadly, I could not find the remainder of that tube of red gasket maker, so I decided get another one. With the location of the valve cover gasket on this riding mower, between the top of the cylinder head and the muffler, I assumed I should best be prepared for the high temperatures. That’s why I chose the Right Stuff 90 minute gasket maker red. It says it’s for temperature is up to 650° and is resistant to oils. Yes, it has a picture of exhaust headers but does that mean it should “only“ be used on headers?
So my question is – why should this NOT be used on a riding lawnmower, single cylinder engine valve cover?

I've adjusted the valves on a few of these. No pro mind you, but the release is just a small rise on the cam that holds the exhaust valve open a little to release some compression just before top dead center while cranking. Thats why the close tolerance on the exhaust valve adjustment is so critical. If the adjustment is too loose by just a few thousandths the exhaust valve closes completely retaining the high compression and the starter may not turn it over. The compression release is there so the starter can turn the engine over faster, or the pull rope is easier to turn. There is no release mechanism. I can't remember the adjustment, but as I recall it is something like.04 on the exhaust valve and .06 on the intake valve. If you adjust the exhaust to .06, the slack is so much the small cam just doesn't open the exhaust valve for the cranking compression release. When the engine is running the small release doesn't matter. I defer to the top guns, am I wrong???

mmoffitt said:

Tons more is not better? But it's the American way.. way over the top!
Happy mowing and be safe!

Click to expand...

If a little is good, then more is better. It's the American way. Applies to many things, like sealant, grease, oil level, premixing oil and gas, sharpening a mower blade, tire pressure, tightening a bolt, etc. I'm sure you can fill in the blanks.

By design, engine running centrifugal force and a small spring retract the cam compression release mechanism.

TLloyd said:

OK, all this about what kind of gasket maker to use is more confusing to me than helpful.

Click to expand...

I told you what I use. It is non hardening. As in EASY to remove NEXT TIME. Saves the next guy from cussing his brains out.

TLloyd said:

I pulled off the gasket cover and had no trouble removing the Permatex gasket material

Click to expand...

Totally stunned and believe your story. Normally when I see RTV, there are tools laying all over the place trying to remove a small valve cover for example.

TLloyd said:

So my question is – why should this NOT be used on a riding lawnmower, single cylinder engine valve cover?

Click to expand...

You can, use red. It will work. Issue is there are more specific formulas of RTV glob to use in an oil sealing environment.