Export thread

31p977 0575 e1
The choke stays on no matter where the throttle lever is.
What did I do wrong?
Thanks
Bob

Does throttle cable move length of travel?

Yes
Even if the choke lever could go farther, the lever on the carb can't go anywhere.
Maybe I put the spring on backwards?

No you didn't do anything wrong. The problem is the plastic choke shaft in the carburetor is sticking. They do swell sometimes. The repair will require removing the carburetor so the choke shaft can be removed. Then using fine file or sandpaper rework the two parts of the that goes through the bushing holes of the carburetor just enough until the choke freely rotates again. Note don't over do it or get the shaft out of round.

Meant white grease

ba_50 said:

Meant white grease

Click to expand...

Well, at least it might catch some grit going into the engine. Never heard of greasing a choke plate but my ears are open.

slomo

StarTech said:

No you didn't do anything wrong. The problem is the plastic choke shaft in the carburetor is sticking. They do swell sometimes. The repair will require removing the carburetor so the choke shaft can be removed. Then using fine file or sandpaper rework the two parts of the that goes through the bushing holes of the carburetor just enough until the choke freely rotates again. Note don't over do it or get the shaft out of round.

Click to expand...

As StarTech said, some carbs especially Chinese carbs might need some tweaking. Tooling gets dull and holes are not proper and so on.

slomo

I greased the bottom of the choke shaft.
The valves were adjusted at .004".
Checked again and the cap at the rocker arm was off.
Those two bolts were tight.
Cleaning the carb didn't help.

The valves were adjusted at .004". It starts on choke but runs only at slow speed for a bit then dies. Moving the linkage rods doesn't help.

Did you remove the choke plate AS INSTRUCTED on page 1?

There was no guidance to use any grease on any carb part.

If your engine has the valve stem caps on each valve, make sure they are on each valve.

Your Briggs engine manual is below. Click on the link.

Your valve clearance settings are wrong. Per your Briggs engine manual below.

Specifically

ba_50 said:

The valves were adjusted at .004"

Click to expand...

This is incorrect.

ba_50 said:

It starts on choke but runs only at slow speed for a bit then dies

Click to expand...

Possibilities below

carb linkages need proper adjustment
dirty carb
dirty fuel tank
dirty fuel filter
fouled spark plug
air filter plugged
gas cap vent is bad

Remove fuel line AT carb. Drain into a glass jar. Should have good fuel flow.

ba_50 said:

Moving the linkage rods doesn't help

Click to expand...

Either choke plate is binding or choke linkage need tweaking.
Insert a piece of thick paper ALL AROUND the choke plate inside carb body. Make sure nothing binds.
NO GREASE

Here is your how-to engine manual. Look at the carb linkage settings in section 4.

Intake top 004
Exhaust bottom 006
Soaked Briggs carb in cleaner overnight, used wire and air to blow out
Choke plate isn't sticking
Greased bottom of shaft before you posted about it.
Gas tank is clean, fuel flow ok
Linkages same as when it was running.
Fires but won't run now.

ba_50 said:

Intake top 004
Exhaust bottom 006

Click to expand...

Explain exactly the stroke you checked the valves on. There are 2 TDC positions on a 4 smoke engine. Should be 1/4" PAST TDC on COMPRESSION stroke.

ba_50 said:

Soaked Briggs carb in cleaner overnight, used wire and air to blow out

Click to expand...

Might need to boil the carb per Bertsmobile1's suggestion. Could take a few times to get it clean.

From Bertsmobile1 below. Great advice.

"Before I got the ultrasonic cleaner we used to boil carbs using a big pot & a dishwasher tablet
The ones with the ball in the middle seem to work better
A nice rolling boil works best
Give it an hour or so then boil some more water and take it out of the boiling soapy water then strait into the boiling rinse water
Give it a 5 minute rinse hen take out & blow dry.
Do not allow the carb to sit in the wash water unless it is boiling or it will oxadise.
Some like to do a pre-rinse in boiling water with some vinegar in it to neutralise the alkaline soap first."

Turned out 1/4" past dead center and set gaps.
Tried a different plug this morning and nothing.
Checked plug for fuel and it was dry.

I will send the choke shaft this time.

ba_50 said:

Intake top 004
Exhaust bottom 006
Soaked Briggs carb in cleaner overnight, used wire and air to blow out
Choke plate isn't sticking
Greased bottom of shaft before you posted about it.
Gas tank is clean, fuel flow ok
Linkages same as when it was running.
Fires but won't run now.

Click to expand...

Wrong. This engine uses a cross flow head design. The exhaust valve is closest the flywheel and the intake is closer to the PTO end.

Also it still sound like you have carburetor problems. When cleaned the carburetor and removed the fuel transfer tube you may have lose the main jet. THey are only held in by oring which does strink and gets loose. Can be easily blown by compressed air. Once blown out they are nearly impossible to find.

But with the plug dry you may have a fuel solenoid not working too.

Boiled in soapy water for 1 hr, fresh water 2x. No fuel.
The fuel solenoid tests ok.

The jet is ok.

Still no fuel.
Put a new Chinese carb on, same thing.
I changed the valve settings and torqued them at 40#

Update
After several attempted starts is getting some but not enough to keep running.

ba_50 said:

I changed the valve settings and torqued them at 40#

Click to expand...

What is this exactly? 40ft lbs or inch pounds?

Take pictures of what you are doing. Videos are even better. Post to youtube and link the videos here.

slomo

You need air, fuel, spark and compression. Start from these basics.

Dry plug is no fuel getting to the plug.

Gas cap vent bad?

Is the choke working or not?

slomo

I have tried 3 carbs after soaking in cleaner. The motor will run if spraying carb cleaner at the air intake. My cleaner is old and may not be effective.

ba_50 said:

I have tried 3 carbs after soaking in cleaner. The motor will run if spraying carb cleaner at the air intake. My cleaner is old and may not be effective.

Click to expand...

Again - is the choke working or not?

slomo

The compression went from over 100 to 40#. The choke on the original carb works ok.
The intake valve isn't moving when the motor is cranked. Sprayed both with penetrating oil. Didn't help.

ba_50 said:

The compression went from over 100 to 40#. The choke on the original carb works ok.
The intake valve isn't moving when the motor is cranked. Sprayed both with penetrating oil. Didn't help.

Click to expand...

Remove valves. See if they come out of the block ok. Wondering if a valve guide is tight yo'.

Sounds like a camshaft problem now. Intake valve is not opening. Time to investigate the cam.

slomo

Either that or the push rod is not installed correctly on the tappet. Check by shining a light down the galley and check the positioning of the push rod.

There was too much clearance and the push rod wasn't moving it. Not sure how that happened. A friend said to use the high end of the valve clearance because when they get hot it tightens up. It runs ok now except for surging.

ba_50 said:

There was too much clearance and the push rod wasn't moving it. Not sure how that happened. A friend said to use the high end of the valve clearance because when they get hot it tightens up. It runs ok now except for surging.

Click to expand...

But the problem with OHV engines is that the valve clearances tend to open as the valve wears so here I always set at the minimum setting as to have the adjustment last longer between tune up. Also make sure the valve stem caps are in place too.

ba_50 said:

There was too much clearance and the push rod wasn't moving it. Not sure how that happened. A friend said to use the high end of the valve clearance because when they get hot it tightens up. It runs ok now except for surging.

Click to expand...

ba_50 said:


The valves were adjusted at .004". It starts on choke but runs only at slow speed for a bit then dies. Moving the linkage rods doesn't help.

Click to expand...

Thought the valves were adjusted a few pages ago.

Hard to help when nothing is done proper.

slomo