Wife wanted a burnout! Now the car is sick ( the cough kind, not the cool kind)!!!

[Ranger16]

OK, gotcha, but assuming that black thing is a pointer, I don't see a leak point unless the intake gasket as Shorthorse said.

 

[dvw]

OK, gotcha, but assuming that black thing is a pointer, I don't see a leak point unless the intake gasket as Shorthorse said.

5 pages of this thread. The original poster reved the motor to the moon. We've had discussion about spark, carbs, fuel, oil and yet a few bolts haven't been removed to look at the valve train, really????
Doug

 

[Dako]

5 pages of this thread. The original poster reved the motor to the moon. We've had discussion about spark, carbs, fuel, oil and yet a few bolts haven't been removed to look at the valve train, really????
Doug

6,000 on a 340 is not to the moon.

 

[wsutard]

5 pages of this thread. The original poster reved the motor to the moon. We've had discussion about spark, carbs, fuel, oil and yet a few bolts haven't been removed to look at the valve train, really????
Doug

I'm getting there. Takes time, which is in short quantity these days.

6,000 on a 340 is not to the moon.

Also, it briefly hit 6,000. I didn't hold it there for 10 seconds.

 

[Dako]

Most likely, it was someting carb related and has cleared itself. Something mechanical usually doesn't just go away. Drive and monitor...no need to tear into it if she's running fine.

 

[wsutard]

Most likely, it was someting carb related and has cleared itself. Something mechanical usually doesn't just go away. Drive and monitor...no need to tear into it if she's running fine.

I did find a vac leak by an intake bolt. Might have to replace the gasket. Not sure yet.

 

[wsutard]

Decided to pull the plugs. Guess which one is in line with the vac leak? #6. I didn't pull the last two because the header is in the way.

What should this tell me?

 

[wsutard]

New info, #5 and #7 are carbon fouled as well. What do I do/check/rip apart?

Recapping:

• Wife wanted burnout
• Sweet burnout, rpm spiked at 6k
• Back fires in 2nd at 2300 rpm heading down the hill to house
• Rough, struggling to hold idle at 500-400. Normally idle 650-700, not rough
• Next day, took carb apart and put back together. No issues found.
• No fuel filter issues.
• Start car up, idles fine in both fast and normal idle.
• Timing set at 10degrees at idle
• Vacuum leak found at intake manifold bolt right above #6 cylinder.
• Ran fine for 50 miles yesterday.
• Pulled plugs today, #5,6,7 plugs are carbon fouled.

 

[ZR9B]

blinker fluid??

 

[wsutard]

 

[BeatersRus]

it tells me that your gasket has been leaking for awhile from the plugs all being fouled.
id guesstimate your burnout probably sucked in a piece of intake gasket and id fix that sooner than later if it was me.
btw,
not to be a parrot here but you Should get some valve cover gaskets too and check things out while you are doing the intake gaskets.....
and while you have the intake off,
shine a flashlight up inside the front and look at the timing chain as well....
plus,id check the wires for header burns..just in case.

 

[wsutard]

All the gaskets are on order. Went with Felpro for both. I didn't realize that the intake gasket could lead to fouled spark plugs.

 

[Cranky]

Have you been studying spark plugs? Lots of reasons for carbon fouling.....and nothing there looks overly lean to me. https://www.ngksparkplugs.com/about-ngk/tech-talk/spark-plug-basics

 

[BeatersRus]

if its sucking oil it very well could be.
youll see the bad spots/pattern on the old gaskets when you pull them off.

and hey drain your radiator first okay.
make sure you drain the lower hose going to the radiator as well.

 

[wsutard]

yeah. Been looking into spark plug issues. Carbon is caused by a rich situation. Seems like vacuum leak can cause that. Either way, I need to get the intake gasket changed out.

 

[wsutard]

if its sucking oil it very well could be.
youll see the bad spots/pattern on the old gaskets when you pull them off.

and hey drain your radiator first okay.
make sure you drain the lower hose going to the radiator as well.

Why is this?

 

[BeatersRus]

because otherwise you gonna have antifeeze soup inside your motor.

 

[wsutard]

seems like a valid reason!

 

[Cranky]

Small blocks have 'wet' intakes on them.....

 

[wsutard]

Also learned that I should put rtv surrounding the water jacket areas.

I'm still up in the air about rtving the other openings. Some say to do so, others say, depending on the gasket, not to do it as rtv can squish into the passage and harden, causing air flow issues.