sick florida 5.0

[markjohn]

need help my 91 5.0 conv all of a sudden started to smell like gas comming from the exaust and it seems like it is running on about 4 cylinders. the strange thing is i would park for almost any amount of time 2min/2 days and it seemed to run great. recently however it only seems to run good for only a few seconds then starts acting up. someone said it might be some sort of valve (not an engine valve i hope). i have noticed blue smoke comming from the exaust after idle when it runs bad but not when it runs [email protected]

[Silver Fox]

Originally Posted by markjohn

need help my 91 5.0 conv all of a sudden started to smell like gas comming from the exaust and it seems like it is running on about 4 cylinders. the strange thing is i would park for almost any amount of time 2min/2 days and it seemed to run great. recently however it only seems to run good for only a few seconds then starts acting up. someone said it might be some sort of valve (not an engine valve i hope). i have noticed blue smoke comming from the exaust after idle when it runs bad but not when it runs [email protected]

Markjohn

A couple question.

How many miles do you have on the motor?
Does the smoke happen when you start up after the engine has idled for a while? Like when you're setting at a stop light.

These are some possibilities and some things to check.

1 Pull all eight spark plugs and check them for excessive oil deposits. If 3 or 4 of the plugs are coated with oil and they smell like burnt oil, then the problem might be your valve guides are worn out.

In each head you have 4 intake valves and 4 exaust valvwes. Each valve pased through a valve guide usually made out of brass.

The oil pump sends the oil up into the head to lubricate the valve train and it drains back into the bottom of the motor. Your valve guides and seals keep the oil from draining back into the cylinders.

When the seals and guides wear out it allows the oil to seap back into the cylinders while you are setting at idle, then when you accelerate the oil that has built up burns. this is where you get the blue smoke. When the problem first starts It only happens when you first take off. Eventually it will smoke all the time.

The only solution is a full valve job on the heads. If you have this problem with the valves the rest of the motor probably needs to be rebuilt too. Sounds like the motor has over 100,000 miles on it.

Good luck

Kent Mathew
Dallas, TX