first start break in

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j par

j par

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I'm thinking about taking the thermostat out for the first start to keep it as cool as possible and not have a burp problem. I know some people put holes in the thermostat, but I was thinking of pulling it for that 2000+ rpm break in for 30 minutes. I'll be trying some new electric fans at the same time so I don't want any current problems on trying to run this motor that hard for that long for the first time. What do you think? Thank you
410 stroker with solid cam & lifters
 
I wouldnt think you would have any problems if your cooling system is on par. I've seen guys put a garden hose in the thermostat housing too. When breaking in a new cam if you have any problems your supposed to shut it down right away. But if your worried about overheating you can always do it in intervals. It's not going to hurt the engine to run for 10 minutes and then cool down and run it for another 15 or so and then another 10. I had to do this one time because I had terrible neighbors. They would call the police anytime I was doing anything to the car for prolonged periods of time. Such as replacing floors, so Alot of cutting and grinding and whatnot. So when I broke in my new cam I ran the engine for about 10 minutes one day, then the next day I ran it for another 10 and then the day after that I ran it for another 15 minutes. I'm sure someone will say something about it not being good for it. But I don't see why it would be a problem unless someone gives me a bona-fide reason.
 
I use a restrictor washer. Basically a gutted stat.
Some say at 2000rpm, with no stat/restrictor, that the water may not be in the motor long enough to extract enough heat, or that hot spots could occur. I dont know anything about that or how to prove it, so I just use the restrictor.
Good luck with your new motor!
 
j par said:
I'm thinking about taking the thermostat out for the first start to keep it as cool as possible and not have a burp problem. I know some people put holes in the thermostat, but I was thinking of pulling it for that 2000+ rpm break in for 30 minutes. I'll be trying some new electric fans at the same time so I don't want any current problems on trying to run this motor that hard for that long for the first time. What do you think? Thank you
410 stroker with solid cam & lifters
Click to expand...

Drill the stat, put it back in and be done with it for good.
You will never have that "burp" problem again.

You can fill it with coolant, and then as soon as it's running you can top it off because the 1/8 hole in the stat will let the bubbles from the block out right away instead of getting hot spots till it opens.

Now if you want to try and keep it cooler than actual running temp during initial break in, that's a different story.
Leaving the stat out could very well cause it to overheat and have to be shut down before your break in time is done. (like already mentioned)
 
Leave thermostat in place. If it doesn't have a bleed hole, put one in it. When you fill the engine with water, jack the front end up, so t-stat is the high point of engine. That will help get air out of your engine.

Get two large box fan and have them blowing in the front of your car.
 
TrailBeast said:
Drill the stat, put it back in and be done with it for good.
You will never have that "burp" problem again.

You can fill it with coolant, and then as soon as it's running you can top it off because the 1/8 hole in the stat will let the bubbles from the block out right away instead of getting hot spots till it opens.

Now if you want to try and keep it cooler than actual running temp during initial break in, that's a different story.
Leaving the stat out could very well cause it to overheat and have to be shut down before your break in time is done. (like already mentioned)
Click to expand...

I was going to use distilled water instead of antifreeze because I believe it cools better?
 
crackedback said:
Leave thermostat in place. If it doesn't have a bleed hole, put one in it. When you fill the engine with water, jack the front end up, so t-stat is the high point of engine. That will help get air out of your engine.

Get two large box fan and have them blowing in the front of your car.
Click to expand...
I'm wondering if when I pull the thermostat to drill the hole that at that point i can just fill the block up with water through the housing?
 
j par said:
I was going to use distilled water instead of antifreeze because I believe it cools better?
Click to expand...

I have never seen any real evidence of that, but I suppose if the minerals are taken out it could make a difference.
Personally, I would do the stat mod and get the biggest 110 volt fan I coud find in front of the radiator during the break in.

On the stat subject, I have seen and worked on a lot of cars that got hot spots from air in the block and push the water out faster than you can try to get in there before the thermostat ends up opening.
Then when it finally opens the new coolant gets blasted back out from contacting those hot spots. (I know people that have been burned pretty bad from this.)
Even if that doesn't happen you still have to wait for the stat to open to be sure the system is actually full and the air bubbles are out of it.
With the 1/8 hole in the stat housing this NEVER happens as the air gets circulated out as soon as the engine starts and before the stat ever opens. (hot spots never get the chance to form)
This way, you put coolant in it till it's close to full and start the engine.
As soon as the engine is running you can top it off and put the cap on.
That's it.

It makes things WAY easier and faster even if you are just changing a hose or something later on.

I can only imagine a lot of people don't understand what the advantage to the hole is, or everyone would do it when they put a stat in.

Then there's the question "If it works so well and such a good thing, then why are they not made this way in the first place?"

Well, some are. :D
Some have a hole with a little brass or whatever pin in it that fits loosly, and they call them jiggle valves.
I have even seen the same hole with a cotter pin in it with the legs of the pin flared so it stays there.

Where this picture says the air valve must be up, is because this thermostat sits upright instead of laying down flat like ours do.
 

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I once had a brandy new stat stick closed during the break in procedure. Thats why I always use the restrictor washer.Theres nothing like a good panic to make you rethink your methods.
And I always use water during the cam break-in, and often for the first couple of hundred miles. It is a far superior coolant to anything else. Once the engine has a reasonable tune in it, and shows a history of not running hot, then the 50/50 can go in. I would hate to lose an expensive engine to something so preventable.My bosses always have liked that about me, when I dont cost them money, needlessly.

Oh yeah, drill the stat for sure; theres no down side to that.
And yes you can refill the block through the stat house, if you like.
 
The air release hole in the t-stat is a good idea and as shown, some stats come with a bypass. You can use water for break-in but antifreeze has a higher boiling point. Water's boiling point is 100 C = 212 F. Straight ethylene glycol's boiling point is at 197.3 C = 387 F. Of course, you shouldn't use straight ethylene glycol in the radiator either for the sake of efficiency. Because it is a new engine and hasn't been thoroughly tested with water in the system, you can drain it out, repair leaks, and refill without wasting any coolant. Or you can fill it with a 50/50 mix and catch it in a pan if you need to drain it out. You should always use a good radiator cap also if you are concerned about overheating. For every pound of cooling system pressure it raises the boiling point 3°. A 15# cap will add 45° to the boiling point. tmm
 
Use coolant, water by it self does not transfer heat as well as coolant/water mix, reason being is that coolant has "wetting" agents and a higher boiling point so that it will not boil at the contact boundary. Bubbles do not transfer heat.

Drill a vent hole in the stat.
Test the T-stat on the stove in a pot of water if you want to be sure it works right.
 
Anti-freeze, by itself, is a lousy coolant. Almost every overheat Ive ever encountered could be solved, or at least alleviated, by straight water. The reasons we use it are, for freeze protection. The additive package can be purchased separately .
-I run straight water all summer, with the additive pkg. I run a 7 pound cap, and a 205* stat. Has worked flawlessly for 15 years and 125,000miles.Little 366/430 hp, no A/C.Impossible to overheat. 50/50 goes in in the fall, out in the spring.
 
I used the restrictor washers and ran water. I wanted to make sure I didn't have any leaks before adding anti freeze but this was my street car.
 
Here's a quote from a scientific website about water vs. coolant:
Anti-freeze (ethylene glycol) has several functions as a heat exchange medium in an automobile engine. One is, as you point out, to reduce the freezing point of the heat exchange fluid. But the freezing point of pure ethylene glycol is -13 C. (which is only 8.6 F.) so at first this does not seem like a very likely candidate for an "anti-freeze". But the process is more subtle. Mixtures of ethylene glycol and water freeze at temperatures less than either component. In addition, both ethylene glycol and ethylene glycol / water mixtures tend not to freeze but rather form a viscous glass instead. As an aside, glycerol has a melting point of 17.8 C., but few people have ever seen crystals of glycerol, because it too tends to form a glass rather than crystallizing as the temperature is lowered.

The boiling point of ethylene glycol is about 198 C. -- much higher than the boiling point of water -- so mixtures of the two can be used as a heat exchange fluid at temperatures significantly greater than 100 C. at significantly lower pressures than water alone (in a closed system). In principle, water alone could be used as a heat exchange fluid, but its vapor pressure doubles from 1 to 2 atmospheres at a temperature just over 120 C. So the problem becomes one of engineering hoses, fittings, etc. that could withstand high pressures if water alone were used as a heat exchange fluid.

When the term "boiling over" is used in the context of a heat exchange medium what is meant, as I am sure you know, is that the pressure of the fluid is greater than atmospheric pressure and the fluid evaporates until the pressures are equal.

In the "real world" there are a number of other factors that need to be taken into account, such as corrosion, and viscosity.

Vince Calder http://www.newton.dep.anl.gov/askasci/chem03/chem03987.htm
 
Thank you for everyone's information about the thermostat ! I'm trying to over think everything before i start the motor for the first time .
as always I'd like to say I'm less confused than when I started the thread , but .....#-o
 
j par said:
Thank you for everyone's information about the thermostat ! I'm trying to over think everything before i start the motor for the first time .
as always I'd like to say I'm less confused than when I started the thread , but .....#-o
Click to expand...

Lol, just use some common sense.

Drilling the hole in the stat is an absolute benefit, I do all of mine that way. Raising the front of the car while you fill the cooling system will help "burp" it. Use a mix of water/coolant

When you prepare to do the breakin, make sure the timing is set right, make sure you have a good known carb. Make sure you have enough fuel in the tank to complete the breakin process. Double check your oil level.

It's real handy to have someone with you, one to operate the throttle, and the other looking for leaks and listening for problems. Mufflers at a minimum on the headers if you don't have the exhaust on yet. Much easier to hear any problem.

Have on hand, a fire extinguisher/garden hose if you're in a climate that allows it this time of year, a box fan for in front of the radiator, a screwdriver in case you need to tweak the carb slightly.

Fire that puppy up and have at it.

Good luck!
 
Bad Sport said:
Lol, just use some common sense.

Drilling the hole in the stat is an absolute benefit, I do all of mine that way. Raising the front of the car while you fill the cooling system will help "burp" it. Use a mix of water/coolant

When you prepare to do the breakin, make sure the timing is set right, make sure you have a good known carb. Make sure you have enough fuel in the tank to complete the breakin process. Double check your oil level.

It's real handy to have someone with you, one to operate the throttle, and the other looking for leaks and listening for problems. Mufflers at a minimum on the headers if you don't have the exhaust on yet. Much easier to hear any problem.

Have on hand, a fire extinguisher/garden hose if you're in a climate that allows it this time of year, a box fan for in front of the radiator, a screwdriver in case you need to tweak the carb slightly.

Fire that puppy up and have at it.

Good luck!
Click to expand...
well I think I'll have most of those bases covered. The car is already jacked up to the front tires are off the ground to put the motor back in actually that's the way it was since its been out.I got a new fuel cell so I'll be filling that up with aviation fuel. I have the headers already hooked up to the glass packs and kicked out the side. Not exactly the quietest setup but I like it. I've got the dual quads from the 318 and I left them and never touch them so I'm hoping they'll be in some kind of tune. As far as the timing I'm going to find number 1 on its firing stroke on top dead center turn motor at 10 degrees before top dead center and then turn the distributor back and forth to the number one spark plug fires set up there. I guess I'll try and find a fan it's not going to be really hot here in Oregon but it won't be below freezing either. even as prepared as I can be with a friend handy I'm still going to be on pins and needles til its running right .
 
Once you get it started and RPM up to 2000ish, put a timing light on it and bump the timing to 36-40* BTDC. That will help keep your headers from glowing.

Even if it's cold out, get a fan to blow through the grille.
 
crackedback said:
Once you get it started and RPM up to 2000ish, put a timing light on it and bump the timing to 36-40* BTDC. That will help keep your headers from glowing.

Even if it's cold out, get a fan to blow through the grille.
Click to expand...

Will do :thumbrig:
 
toolmanmike said:
Here's a quote from a scientific website about water vs. coolant:
Anti-freeze (ethylene glycol) has several functions as a heat exchange medium in an automobile engine. One is, as you point out, to reduce the freezing point of the heat exchange fluid. But the freezing point of pure ethylene glycol is -13 C. (which is only 8.6 F.) so at first this does not seem like a very likely candidate for an "anti-freeze". But the process is more subtle. Mixtures of ethylene glycol and water freeze at temperatures less than either component. In addition, both ethylene glycol and ethylene glycol / water mixtures tend not to freeze but rather form a viscous glass instead. As an aside, glycerol has a melting point of 17.8 C., but few people have ever seen crystals of glycerol, because it too tends to form a glass rather than crystallizing as the temperature is lowered.

The boiling point of ethylene glycol is about 198 C. -- much higher than the boiling point of water -- so mixtures of the two can be used as a heat exchange fluid at temperatures significantly greater than 100 C. at significantly lower pressures than water alone (in a closed system). In principle, water alone could be used as a heat exchange fluid, but its vapor pressure doubles from 1 to 2 atmospheres at a temperature just over 120 C. So the problem becomes one of engineering hoses, fittings, etc. that could withstand high pressures if water alone were used as a heat exchange fluid.

When the term "boiling over" is used in the context of a heat exchange medium what is meant, as I am sure you know, is that the pressure of the fluid is greater than atmospheric pressure and the fluid evaporates until the pressures are equal.

In the "real world" there are a number of other factors that need to be taken into account, such as corrosion, and viscosity.

Vince Calder http://www.newton.dep.anl.gov/askasci/chem03/chem03987.htm
Click to expand...

I am pretty sure one of the tracks here has a rule that you can only run water.
 
And two of the reasons for that are, 1) antifreeze is greasy when you drive on it or even walk on it, and 2) it burns with a nearly invisible flame.
I guess that just one reason;Safety.
 
there is some good advice here and some that is pure bullshit its up to you to sort it out .
 
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