Smoke part II

[66Sprint6]

Okedokee,
so in our last adventure, we all came to the conclusion that my smoking at idle was probably cause by rings. Now try this one on for size.
When I am getting on it hard in 2nd or 3rd, pushing the rpms to 3-4k, the stang lays down a nice cloud of smoke behind the car. It doesnt run rough or anything, it runs quite well actually, but you can see the smoke in peoples headlights. Then once I shift and go to a lower cruising rpm, no more smoke, and Im good to go. Still rings you think??? What yall think of this one. Again, no hinderance to performance, that I can tell, but it smokes. Its really odd
Matt

 

[godheadcustoms]

Yeah, still probably rings. If it was smoking on decelleration, then I would say valve guides/seals, but upper RPM/load smoking then probably rings, unless you are running really rich under load. Have you done a wet and dry compression test? That will tell you pretty quick what kind of shape your rings and valves are in. If you can, I would also do a leak down test. This can give you a much better "picture" of the overall condition of your engine.
Sorry if alot of this info has been gone over before, but I didn't see your prior post. I guess I could have done a search, but I'm being lazy :roll:

 

[66Sprint6]

Dont even worry about it, I appreciate the help!! I havnt done anything like that, how do you do a leak down test? What all is needed to do a compression chech and all that. Ive never done any of this, so its new to me. Thanks alot! Im praying its just the rings so I dont have to rebuild before putting the turbo on. Its been pushed back by so many stupid things already.
Matt

 

[godheadcustoms]

To do a compression test you need: a compression tester, a spark plug socket, an oil can, and a friend is helpful.
1. pull all your plugs
2. disconnect/disable your ign
3. screw the tester into a spark plug hole
4. hold the gas pedal to WOT
5. crank engine, let the motor spin 5-6 times. This is where a friend is helpful, or just use a remote starter switch.
6. record data, note total pressure as well as how much initial pressure on the first crank.
7. repeat for all cylinders
On a decent motor, you will get something like a 100psi or so on the first hit, then it will continue building up to approx 150-190psi. All the cylinders should be within 10-15% of each other, and they shouldn't lag to get to the final numbers.
8. repeat as above, but squirt a teaspoonish amount of oil into the cylinders first. What this does is it temporarily seals up your rings, if they are worn/weak. If you get a higher pressure reading, your rings are going south on you. If you get no change or minimal, then your rings are fine. If you have low readings regardless of oil, then your valves probably need some help.

A leakdown test pressurizes the cylinders to see if they hold pressure and/or shows where they are leaking from. A more elegant and accurate way of diagnosing engine problems.

 

[66Sprint6]

Thanks alot godhead!
If my rings are bad, should I try and fix this imediately or will it be ok for the time being? I need to keep driving the car (my only car) and I dont have alot of money to put into it as of right now. Will it hurt anything to keep driving it, or will it be alright? Thanks again
Matt

 

[godheadcustoms]

Depends on the shape of the rest off the motor. If you have decent compression and your not blowing too much smoke, you can crutch your car along for quite a while using something like STP or "no smoke". Just replacing the rings is false economy. If you just "fixed" the rings now, chances are you will be going into the motor again in the not too distant future. Better to save your pennies and do a proper rebuild when the time comes.
It all depends on what your testing reveals. Post your results, so we can try to make a diagnosis and help send you in the right direction. BTW, you can usually rent or borrow a comp. tester from some of the bigger auto parts chains.

 

[66Sprint6]

Ill try to do the tests sometime this upcoming weekend if it isnt too hectic! So far it only smokes at idle and when you get on it REALLY had in the upper RPMs, and thats usually only when the car has been driven ALOT that day, so its not a huge deal so far. I have been trying to do a turbo set-up for the past year or two and it just keeps getting pushed back. Once I pay off the tranny I will save for a rebuild and turbo...wish I had some money tho!!!!!!
Matt