Thread: 350 Engine question

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Earlier this year due to some oil pressure issues we swapped out a 67 327 for a 72 350 in our coupe. Engine was pulled from a truck and had no problems so we stuck it in hoping for some summer cruzin. It seemed to be doing fine but.... Here is the question/problem, we just returned from the Goodguys Nationals in Columbus and for longer weekends we pull a small trailer for cooler ect. We noticed on pass side of trailer there was a bunch of oily specks looks like coming from pass side exhaust. We put 600 miles on before this trip but had never hooked up trailer so didn't know this was happening. Engine has good oil pressure. Would this be something like oil seals or rings or what, where should we start to look for a repair or is it even a problem besides trailer cleaning? Drivers side looks fine so just on the one bank.

Is it losing oil or water? Does it smoke while running or on start up?
I'm thinking it's condensation or water running through the pipes and spitting dirty water on your trailer more than oil. If oil is running through your headers it should be smoking a lot. You will probably end up pulling the head for seals and a new gasket, that should fix it, and have it checked for cracks.
On my 86 Vette, the PCV was pulling oil and dumping it to the egr, then the oil ran into cylinder 6 and kept fouling the plug, didn't figure it out until I did an injector swap and pulled the intake apart. Problem was aftermarket non-baffled valve covers and PCV in rear of engine.

It does smoke some on start-up but doesn't seem real bad. The dirt or whatever on the trailer is definatly not dirty water, if you try to wipe off it just smears around and will need some solvent for clean-up.

How do the spark plugs look?

Sorry for the delay had some other stuff to catch up yesterday. I pulled the plugs on the right bank this morning and they all look the same. They look kinda white. I don't know how they should look for different problems.

Sounds like your plugs look fine - here's a good reference guide for plugs from our friends at NGK:

Normal: Grey to Light Golden-Brown Color
• This condition is ideal, the spark plug and engine air/fuel mixture are operating properly.
Dry: Black Soot Buildup
• Air/fuel mixture is too rich, the carburetor settings are incorrect, or the flame arrestor is dirty or has mounting problems.
• Spark plug heat range is too cold for the operating conditions.
• Ignition system problems causing a weak or intermittent spark.
Wet Fouling: Shiny, Wet, Black Appearance
• Excessive use of the choke (gas fouled)
• Prolonged low rpm operation (gas or oil fouled)
• Fuel to oil ratio is too rich (oil fouled)
Excess Deposits: Bumpy, Chalky Buildup
• Poor fuel quality
• Oil leakage into combustion chamber
• Improper oil used for premix/injected
Overheated: White, Blistered, Melted Electrode
• Lean air/fuel mixture
• Spark plug heat range is too hot for operating condition of the engine
• Plug is not properly gapped and/or torqued onto head
• Overly advanced timing

This may sound dumb but put some turndowns on till you get around to repairing it. Sounds like water to me too. Water will be oily if oil is in exhaust system.

check the transmission modulator with hand held vacuum pump trans oil burns, off white......ted

All white plugs is normal and good news for you, congrats. Now it's back to are you losing any fluids? I still thinks it's condensation or water running through the pipes, picking up the soot and spitting it on your trailer, I've done it before, starting the car with garage closed and it spat all over the door.

I just checked the fluids and oil is maybe down just a little water looked about the same but I will say it is hard to tell because I usually don't keep any water in the overflow. But water in radiator looks the same. I put some in overflow tank and can monitor that. I was wondering could this be oil and moisture built up in exhaust from 327 that is now getting burned out although we have put on 800 miles should be cleaned out. Also on cold startup it really doesn't seem to smoke I just started in garage with door shut and really couldn't notice any smoke. But when stopped a short time and hot it seems to puff some smoke, does this say anything to you pro's?

What's that right side tailpipe look like?

If you rub your finger in the tailpipe it seems to be dry sooty black.

The more I read here the less I think you have an issue. Plugs seem fine (best indicator), no significant loss of oil or water and performs well. I know when I do not drive my '71 Chevy for a while, it blows some nasty black flecks out the exhaust on start up. My theory (and I believe others have eluded to this) is that the condensation in the exhaust is mixing with some of the soft, sooty carbon and that's what causes the black specks..

I think those black specks on your trailer came shortly after start up of the engine.

Take the car for a long drive and get things all warm and toasty. Shut the engine off and then hold a piece of cardboard near the exhaust while a helper restarts. You'll probably not see anything.

Next time it's stone cold and been sitting for day of two, repeat the process and you probably see some of the black specks.

If so - I'd not worry too much as long as oil and temperature remain normal and you do not notice a change in performance.

Enjoy!
Glenn

when an engine smokes on start-up what usually causes it? I thought start up smoke was from valve seals. Can valve seals be done with head on the engine?

Yes valve guide seals are often the cause for smoke on start up. And they can be changed on the car with a valve spring compressing tool. But if you have not done this before study the process before starting the project. It is no big deal, you could do it in a evening.