New rebuild has odd vapors?

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megavites

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so I had my 318LA rebuilt over the summer. A list of components...
.20 over bore, stock pistons w/cast rings, whiplash cam, roller rockers,Performer intake and carb.
Broken in w/ approx. 120 miles on it now. Initially had an intake leak that I corrected.
Before and after oil change I noticed a slight puff on drivers side exhaust.
The other thing is I have a slight vapor out of either valve cover at shut-off.
Plugs look great. Car runs good, except for a slight miss.Compression check is 140-145 across the board.
When I adjusted the edelbrock 1406 idle mixture it seemed to improve a little. Carb was on car prior to rebuild. Unknown what previous owner did.
The one thing not changed yet is the old distributor.
I'm wondering if I could have a compromised head gasket on driver side? I did notice the water level in radiator down some.
Any thoughts on this?

 
megavites said:
so I had my 318LA rebuilt over the summer. A list of components...
.20 over bore, stock pistons w/cast rings, whiplash cam, roller rockers,Performer intake and carb.
Broken in w/ approx. 120 miles on it now. Initially had an intake leak that I corrected.
Before and after oil change I noticed a slight puff on drivers side exhaust.
The other thing is I have a slight vapor out of either valve cover at shut-off.
Plugs look great. Car runs good, except for a slight miss.Compression check is 140-145 across the board.
When I adjusted the edelbrock 1406 idle mixture it seemed to improve a little. Carb was on car prior to rebuild. Unknown what previous owner did.
The one thing not changed yet is the old distributor.
I'm wondering if I could have a compromised head gasket on driver side? I did notice the water level in radiator down some.
Any thoughts on this?

Click to expand...


If you take it to a radiator shop, they can pressurize the cooling system to find any possible leak.
 
If its coolant vapour there would be a sweet smell, no?
Pull oil plug,and drain a little to check for coolant.
If its getting into combustion chamber it would be pressurizing rad. No ifs or whatever. Compression trumps cooling system pressure.
 
here's the break in oil (Joe Gibbs). I assumed I was seeing their additive/zinc.
GGw4d9lfsTRabpct4M3KapEF9D_eyXOIIuQI20T3QGyz8dHI-VNPUI_1XdT0MQCXi6i02sn-4u9veJhRDwA=w483-h858-no.jpg
 
What's your oil look like currently, any oil froth on the underside of the oil filler cap? 65'
 
You might want to remove one of the valve covers and take a look. I believe you may have a slight coolant leak. 65'
 
coolant vapor as also slimy to the touch. Throw a tube of stop leak in there for kicks,if your going to pull the heads anyway if that doesnt fix it.
 
jas0162 said:
PCV on one side vent on the other?
Click to expand...
Ok, to answer a few questions.
Plugs look great. No residue.
PCV on pass. side. Capped on drivers side. ( I do have a vented cap I can try).
Trying to tick off things one by one, I'm going to:
1. replace dist. cap (should have done this to begin with)
2. drain small amount of oil to check for cooolant
3. borrow/purchase a radiator press. tester to check for leaks at head (radiator is brand new)
4. do a leak down test
 
PVC has to have somewhere to pull air from. That is why the valve is on one side and a filtered breather to outside air has to be on the other side.
pcv_system_extracting_moisture.jpg
 
Thinking intake manifold gasket........aftermarket performer intake might not sit flush with new gaskets or might need to be re torx.?
 
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Capt46 said:
Thinking intake manifold gasket........aftermarket performer intake might not sit flush with new gaskets or might need to be re torx.?
Click to expand...
So....I did find that the intake needed to be re-torqued. Still have whitish exhaust on driver side.
Cap good, rotor changed.
Vented cap put on drivers side valve cover. No change to exhaust.
Pressure tested radiator at 16 psi. Very small leak on passenger side exhaust bolt. Tightened all bolts. Exhaust seemed the same, but it was cold and dark.
Press. dropped to 15 psi after 15 mins. Held 16 for 10mins?
Will post video tomorrow of exhaust again.
Still need to drain some oil to check for any coolant and also leave cap off to see if any bubbles in radiator.
 
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megavites said:
just to clarify...press. test done on non-running warm engine.
Re-torque heads has been on my mind and will check.
Click to expand...
Definitely a must at this point......:thumbsup:
Did you run engine long enough for thermostat to open? If test was conducted for 10 min and held 16 lbs then dropped to 15lbs after 15 min engine off but warm how much time did you give to warm engine. just trying to think this out....
 
It might be a little early to tell with cast rings, they sometimes take a long while to break in,but
If your PCV can't make suction at the valve cover at idle, it is a sure sign that either it is not functioning, or it is overwhelmed.
I'd like to see a short vid of the PCV grommet, with the PCV flipped out, and all the valve cover openings plugged except the grommet where the PCV goes, and the engine at 2000 rpm.
Or you can plumb a low-pressure gauge to the dipstick tube.With the PCV properly plumbed, plug all other holes into the crankcase. Then start her up,watching the gauge. At idle,there should be a vacuum there. If the pressure begins to rise, watch closely. If it approaches 4psi, stop the test! We don't want to start blowing seals out.
Pressure means one of three things; 1) the engine isn't "broke" in yet, or 2) the ringseal is very poor, or 3) the headgaskets are leaking.
To find out which, the logical test is a LeakDown test.

White smoke in the exhaust is sorta normal as the engine is warming up. Water is one of the by-products of burning gasoline. It is in the air all around you ,all the time.But after the exhaust system warms up, it isn't usually noticeable. If you suspect the smoke is anti-freeze it will coat the inside of the pipe. If you swipe some out on your finger and touch it to your tongue, it will initially be sweet, then the lingering taste is not very good.
 
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Power brakes? If so check your brake fluid. Pull hose off booster and see if its wet. With brake fluid.
 
Capt46 said:
Definitely a must at this point......:thumbsup:
Did you run engine long enough for thermostat to open? If test was conducted for 10 min and held 16 lbs then dropped to 15lbs after 15 min engine off but warm how much time did you give to warm engine. just trying to think this out....
Click to expand...
Hmmm...I did not run fully up to temp. Wasn't sure I needed to do that. That could be done tomorrow.
Manual brakes...no booster.
I'm starting to get concerned about the possibility of a crack in the head. Don't know if heads where magnafluxed.
I do have a set of rebuilt 302's, but don't know true condition either .(same builder) . Also have original heads from engine.
I'd like to fully test everything before going the route of swapping heads.
Appreciate everyones input! TY.
 
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