Is this normal (cam break-in)?

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MopaR&D

MopaR&D

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I got my 318 started up and proceeded to break-in the cam for about 20 minutes, keeping the revs around 2000-3000. I had filled up the coolant system with water from my garden hose, though, and after about 10 minutes the temp gauge went way up (to around 220*) and the water was boiling into the catch can. I kind of panicked and shut down the engine with still about 10 minutes to go on the break-in. Is this normal for straight water to boil like this, and will I still be able to break the engine in properly? I know the water pump and T-stat are working because after it heated up I saw the upper rad hose collapse, then open back up (I'm assuming as the T-stat opened up).
 
This is just me.I never break in a engine with the thermostat in just for that reason.
 
Just finish your break-in. Between timing, fuel mixture, and possible air trapped behind the stat, any or all could have contributed to overheating - not to mention a fresh motor.
 
MOPEkidD-3 said:
I got my 318 started up and proceeded to break-in the cam for about 20 minutes, keeping the revs around 2000-3000. I had filled up the coolant system with water from my garden hose, though, and after about 10 minutes the temp gauge went way up (to around 220*) and the water was boiling into the catch can. I kind of panicked and shut down the engine with still about 10 minutes to go on the break-in. Is this normal for straight water to boil like this, and will I still be able to break the engine in properly? I know the water pump and T-stat are working because after it heated up I saw the upper rad hose collapse, then open back up (I'm assuming as the T-stat opened up).
Click to expand...

I had the same experience with my 383 cid, had to shut it down after 14-15 minutes due to high temp. After this I measured the cam lobes with a micrometer, fired it up and let it run for another 20 minutes and measured the lobes one more time and it was all fine.
My guess is that your fine.

Next time, have your garden hose ready and flush cold water on the rad when it gets hot.
Don´t ask me how I know. LOL
 
OK, I think it's good now. I let it cool just enough so I could open the rad and filled it back up with water. I started it back up and continued break-in for another 10 minutes or so and in that time it never overheated, so I think it's fine now.

Although I DO have another problem... I'm running a rebuilt ThermoQuad carb now and when I was going around a turn in my neighborhood the engine stalled. I got out to check and when I looked at the carb there was gas dripping quite rapidly out of the jets (and some other orifices I'm not sure are supposed to do that) into the intake manifold. It really scared me because I'm sure that much raw gas going into the engine isn't good for it. I got it started back up though (after putting in a good battery, the old one died) and I had to keep revving it to keep it from stalling again. What usually causes this? I have the carb off now but I want to know what to look for that might cause gas dripping out.
 
Your float level is probably too high. Either that, or you had a piece of crap in the needle and seat - but I'm guessing float level. It stalled because you flooded the engine.
 
I use a balanced Tstat and they have a small hole to let the system completely fill. But I normally dont fill it fully, becaue the coolant expands when heated, and any air has to bleed out without bubbling over. Dpnt worry about it.
 
just a little something I do, but fill the intake as much as you can with coolant also before you put the stat in then button it up and finish filling the radiator. And like the other guys said, scrap the stat untill engine is bout ready to hit the street.
 
I think that's what it was. I took the carb apart and measured the floats and they were off (too high) by quite a bit. Although sometimes I still get some leaking out of one of the jets, which leads me to my next issue. While driving around again the car all of a sudden started to run rough and acted like it wanted to stall. I shut it off and when I looked at the carb I noticed that there wasn't a steady stream of gas coming out when I opened the throttle. I think the fuel bowls weren't staying full enough now; why? I've been driving around with the same half-tank of pump 85 that was in the car when it stopped running about 7 months ago; could the gas be going bad?
 
First, and old man taught me to drill one or two 1/8" holes in the outer part of the thermostat, ( but inside the edge of the sealing surfaces) This prevents trapping air and fills the system. When starting a new engine, I keep a water hose handy to mist the radiator should it run to hot. On the carb sounds like the float level is to low now not filling the accelerator pump cavity. I recommend new floats ( they don't always "float" as they should from age) Set the float level to recommended specs.
 
SG, the better stats will have some sort of hole.. but we're on the same page there.

Kid, if the fuel is 7 months old and no stabilizer was used... theres a good chance it's getting stale. And, if its what we have in terms of methanol fortified... it probably has taken on a bunch of water too. Burn if off fast and get some fresh high test, run a full tank of that (it has better detergents) and then go back to the lower octane. Some people can tell by the scent of it if the fuel is going sour. If it smells a little like turpentine, or is a litte cloudy, it's going bad.
 
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