Pinging Pinging Pinging!!!

[2jeep2think]

Help, my 1986 CJ 7, 258, Carter, 5-speed trans. pings like crazy. Timing is right on the mark. What is the solution?

Thanks!!

 

[Tug-n-pull]

Octan put some high test in there and see if that helps! tug

 

[Bounty__Hunter]

Fix the exhaust leak, sounds like the exhaust manifold.

Have you narrowed down this 'pinging'?

 

[2jeep2think]

Hello and thanks for your reply. There are no indications of an exhaust leak. However, I will use a shade tree stethoscope, (a rubber hose) and check it out.

 

[Snitty]

is it a ticking, or is it a slight knock? does it sound like a baseball card in spokes, or a diesel engine?

 

[2jeep2think]

Sounds just like a diesel engine.

 

[jeeperwilly]

Service Manual from Dingus' website

Come to think of it, Mine sounds like that too. The diesel that is. Probably not as bad as 2jeep2think, but I've always wondered what it was?

 

[Bounty__Hunter]

The 4.0L and 4.2L have what's commonly known as piston slap, some consider it a problem but most ignore it.

 

[Snitty]

mine will do it if my temperature is up... it is often associated with either early detonation, or just simple valve noise... if you raise your octane or retard your timing one degree it might clear up

 

[2jeep2think]

Re: THE SHIELD

Thanks, it is very annoying when going up hills looking for pigs. A buddy, who is a mechanic told me one reason could be because of carbon build up on the pistons. What he does is put the wiper washer hoses into the carb, then go about 40 mph and spray water into the carb. He said that works more time that not. Hmmmmmmmmmmm.

 

[TwistedCU]

What he does is put the wiper washer hoses into the carb, then go about 40 mph and spray water into the carb. .

I'm not sure what you thought of that advice but I would definately not do that.

 

[Bounty__Hunter]

A little H2O is not hard on the engine, but I'm not sure about the washer nozzle, seems like a little heavy on the water.

If you want to clean the pistons and valves, buy a can of SeaFoam and suck it into the intake through a vacuum source like the brake vacuum as per instructions. Also said to clean the catalytic converter.

 

[Snitty]

yeah, carbon can do it.. it takes up space in the combustion chamber and increases the compression ratio.. and will cause knock/ping

 

[ahunt01]

Wow, kinda like my problem...

 

[GaryMB]

Carbon build up is usually more of a problem with high mileage engines; especially if their carbs have been running rich...not too likely in a new fuel injected engine.

 

[ahunt01]

I'm already exploring the lemon law...