Hey guys. Fairly new here. Just finished dropping a brand new 350 rocket (refurbished form Jegs) in my 68 olds.I’ve got about two hours run time on the motor. And now I’m getting white smoke out of my exhaust. Knowing the motor is brand new, I’m hoping that this isn’t a head gasket issue. Just looking to bounce some ideas off of other experienced gents.

 

A lot of times the intake manifold can be leaking causing the white smoke (and of course headgaskets)

did you add the intake?
what gaskets were used?
was sealant used around the water ports ?

 

If it is an automatic transmission look for transmission fluid in the vacuum line going to the modulator.

 

Yea, I added the manifold. I’m really hoping that is the issue over the head gaskets. I used a single gasket for the manifold. The V shaped one. I used RTV in all the proper spots on it but now I’m second guessing that gasket that I used.

 

Is that 2 hours of idle time or on the road?

 

It’s all together time.

 

What happened to the original engine ? I have seen it take quite a while of running to burn off an exhaust system loaded with coolant from an engine failure. Are you losing coolant ?

 

I had that happen once when I was about 18. Took me forever to figure it out.
​​​​​​​-peter

 

Any water in the oil (Milkshake) or oil in the water? Pressure on the radiator cap when it's still not hot, or can you see bubbles when the cap is off. Lots of ways to check if the head gasket is bad before you start taking it apart and spending money. What does Jags have to say about this....Tedd

 

oh boy too much test engineering I've done so what I would do to make sure

1. Take off oil cap look for excessive condensation.

2. Pull dipstick, maybe even drain the oil, look for coolant.

3. Pull all the plugs, and read them are they all a light color tan?

4. Do a compression check of all cylinders.

5. Do a coolant system pressure check, pump up and let sit overnight.

6. Plug all vacuum connections except for distributor advance. Look for any fluid in the vaccum lines

7.. Leave radiator cap off , run engine to normal temp, and do a Combustion Leak Test ( test fluid turns color) and check for exhaust gas.


One can rent most all the test equipment to do this from local parts stores like Autozone for free. Basically you buy it and return it not screwed up..

 

I've seen this before...........