17 HP Briggs valve problems

[EngineMan]

"And I have the aluminum push rod on the bottom and steel on top"

As far as running this doesn't matter as they are both the same length also it is supposed to blow back SOME thru the carb as that is how they relieve some compression in order for the starter to turn the engine. Also, after checking the IPL, it appears that engine has a camshaft made in segments which have a fairly high rate of failure. I would remove the valve cover and make sure both valves open about the same amount. The exhaust valve cam lobe may be worn to where it is not letting enough air out.

I can send you detailed instructions on how to adjust the valves IF you like, address below.

Walt Conner
wconner5 at frontier dot com

aluminum push rod in for the inlet, steel push rod in for the exhaust and it does matter when the engine is running...! do it right the first time.

 

[Boobala]

You did set the valves on the COMPRESSION stroke, and NOT the POWER stroke .. correct ( ie.) 180 * out ..??

MY BAD ... I meant to say compression stroke and NOT the exhaust stroke .. MY APOLOGIES !!

 

[ekywildcat]

You did set the valves on the COMPRESSION stroke, and NOT the POWER stroke .. correct ( ie.) 180 * out ..??

I set them after the intake valve opens and the piston gets back to the top.

 

[ekywildcat]

"And I have the aluminum push rod on the bottom and steel on top"

As far as running this doesn't matter as they are both the same length also it is supposed to blow back SOME thru the carb as that is how they relieve some compression in order for the starter to turn the engine. Also, after checking the IPL, it appears that engine has a camshaft made in segments which have a fairly high rate of failure. I would remove the valve cover and make sure both valves open about the same amount. The exhaust valve cam lobe may be worn to where it is not letting enough air out.

I can send you detailed instructions on how to adjust the valves IF you like, address below.

Walt Conner
wconner5 at frontier dot com

You mean the camshaft is made in independent sections that are put together? If that's the case, that may be the problem. I've eyeballed the valve openings, appear to be the same, but I'll check it better tomorrow. Won't have to remove the valve cover, it's not been on for two days. LOL. Unless you have your own special way to adjust valves, I've probably read a half dozen ways to do it and even made up a few ways of my own.

 

[bertsmobile1]

Where most go wrong is not going the 1/4" back down after TDC on the firing stroke, it does make a difference.
The other biggie that traps people is the outside sleeve nut is the adjuster and the inner grub screw is the locking mechanism.

 

[Tinkerer200]

Where most go wrong is not going the 1/4" back down after TDC on the firing stroke, it does make a difference.
The other biggie that traps people is the outside sleeve nut is the adjuster and the inner grub screw is the locking mechanism.

Agree, also from what OP has said about setting valves, he does need to know the correct way which in my case is simply giving more detail of the way B&S says to set them, but offer withdrawn.

"aluminum push rod in for the inlet, steel push rod in for the exhaust and it does matter when the engine is running...! do it right the first time."

Engineman, In case it was missed, OP is talking about getting the engine running not after it is running and which push rod is where does not matter in getting the engine to run as you seem to indicate. Actually many people are replacing the aluminum push rod with steel, running both steel.

Walt Conner

 

[ekywildcat]

Where most go wrong is not going the 1/4" back down after TDC on the firing stroke, it does make a difference.
The other biggie that traps people is the outside sleeve nut is the adjuster and the inner grub screw is the locking mechanism.

Did the 1/4" down. When the head was off, I got the piston up, down 1/4" and made me a mark on the flywheel. One thing that seems strange is the engine turns clockwise, the instructions in the Briggs pdf manual says to turn it counter clockwise for the 1/4" down measurement. I assume this is correct? Of course I've tried it both ways.

In another thread I read that they had to set the valves on a Briggs at .0015 to compensate for a worn cam lobe. Think I'll try that too.

 

[ekywildcat]

Agree, also from what OP has said about setting valves, he does need to know the correct way which in my case is simply giving more detail of the way B&S says to set them, but offer withdrawn.



Walt Conner

Meant no disrespect Tinkerer, didn't want to bother you, I've read the B&S manual on adjusting valves plus a number of you tube videos. If you can add more detail to the Briggs manual, I'd be grateful to read it.

 

[ILENGINE]

Did the 1/4" down. When the head was off, I got the piston up, down 1/4" and made me a mark on the flywheel. One thing that seems strange is the engine turns clockwise, the instructions in the Briggs pdf manual says to turn it counter clockwise for the 1/4" down measurement. I assume this is correct? Of course I've tried it both ways.

In another thread I read that they had to set the valves on a Briggs at .0015 to compensate for a worn cam lobe. Think I'll try that too.

The flywheel turns clockwise as viewed, but most of the references are for the pto end which is counterclockwise as viewed. 1/4" past TDC on power stroke is the correct position.

 

[ekywildcat]

... 1/4" past TDC on power stroke is the correct position.

Ok thanks, this clears up some confusion I had. :thumbsup: