Intek hard cold starting.

[nbpt100]

I have an early 6.5 hp Intek engine on a walk behind. This looks like a Quantum but is OHV. It has trouble starting and when it does start it lets out a puff of smoke. Engine model 11A602-0151-E1 I have done the following:

Reset the magneto gap to .010
Cleaned the Carb and changed all intake gaskets
Change the spark plug with a new and set gap to .020
Using fresh fuel
Changed the primer bulb
Set valve lash to .005 on both intake and exhaust.

On a cold start it takes a minimum of 4 pulls to starts it Sometimes as many as 8.

On a hot start it can start right up with one pull.

When it starts it will let out a puff of smoke for a few seconds. I assume it is rich gas that did not fully burn. However I realize it could be a leaky valve seal. It runs good once started. No smoking or any issues.

I have not pulled the head to look at the cylinder wall or inspect the valve train. I am thinking that may be my next step but I wanted to post the problem before I dive in to that.
I do not have a leak down tester. Otherwise i would have tried that by now.

Any thoughts?

 

[Rivets]

First thing I would check is the float height. With the carb inverted the float should be level or slightly tilted down for easy starting.

 

[nbpt100]

First thing I would check is the float height. With the carb inverted the float should be level or slightly tilted down for easy starting.

That is a good trick to have in your back pocket. This is a primer style carb and I could test out the low fuel in bowl theory by pumping the primer a few extra times and see if it fires up. If even for a few seconds. But I will take a second look at this. Thanks

 

[Scrubcadet10]

Rich/Gas would be Black smoke, oil from a leaky valve seal would be blueish

 

[mechanic mark]

Results

www.briggsandstratton.com

What grade oil are you using?

 

[bertsmobile1]

That is a good trick to have in your back pocket. This is a primer style carb and I could test out the low fuel in bowl theory by pumping the primer a few extra times and see if it fires up. If even for a few seconds. But I will take a second look at this. Thanks

Add to that blowing through the inlet
If you have a pump, the float upside down should hold 4-7 psi without leakage for at least 5 minutes
Otherwise just blow through it holding your breath but please stop before you urn blue .

 

[nbpt100]

Results

www.briggsandstratton.com

What grade oil are you using?

SAE 30

 

[nbpt100]

Add to that blowing through the inlet
If you have a pump, the float upside down should hold 4-7 psi without leakage for at least 5 minutes
Otherwise just blow through it holding your breath but please stop before you urn blue .

That is a good trick to have know as well. However, i Do not believe the carb is flooding.

I think it is time to remove the head and do some inspection.

 

[slomo]

Check for vacuum leaks. This Intek has a manifold that runs to the other side of the block from the carb. Check both sides with WD-40. If engine smooths out or smokes you've found your leak.

I think it is time to remove the head and do some inspection.

Should be done anyway to remove carbon in the cylinder and head.

Notice the last 2 items in the below list from your manual........

 

[nbpt100]

Check for vacuum leaks. This Intek has a manifold that runs to the other side of the block from the carb. Check both sides with WD-40. If engine smooths out or smokes you've found your leak.


Should be done anyway to remove carbon in the cylinder and head.

Notice the last 2 items in the below list from your manual........


View attachment 58196

I have done everything , if possible, on this list.