I have an 87 with a 13b N/A ... got it back from a shop that put a different 13b n/a because my other engine went bye bye. I noticed that with the newly installed engine there is no nipple for an overflow tank tube on the fillcap housing and the overflow tank is not being used at all. Is the overflow tank necessary for healthy life of the vehicle? I am familiar with how the give and take system works, but it is unclear to me why he might of gave me the engine without this seemingly necessary feature? and why do they even make the coolant fillcaps without the nipple ?? what would you do if you were me ? Also I searched around and could not find any threads that gave me a clear answer so any help is appreciated. thanks guys

 

You'll be fine. It's just harder to purge the air out of the system. The res makes bleeding the system fool proof and is a nice safety feature should something go wrong with your coolant system.

 

So the extra pressure that the coolant system has without an overflow tank is fine ? I dont want my seals to mess up in the future.

 

Personally, I'd want the overflow reservoir. The cap will/should release pressure when it reaches the set psi so that no excessive pressure will buildup within the cooling system, so there's got to be a release area somewhere. Without a reservoir tank the coolant should "pump" out through some relief area into the atmosphere, then the water level will be low when cold. With a reservoir, the coolant will be pumped into the tank and brought back int the radiator when cooling so that it stays full all the time.

 

I agree that having it is much better than not having it. Like Turbonut said, you might find yourself having to top up once every so often. You might also have dogs and cats hanging around your car lol. Your coolant level sensor would let you know you need a top up. Hopefully that is working on your car.

 

I would find a used coolant overflow bottle and purchase the cap pedestal from Mazdatrix. Link below. It would be better to have a proper burping/auto filling system as per the original design of the car.

HALF WAY DOWN : Radiators, Caps, Water Level Sensor

 

thank you guys and thank you for the link. I figured it was made like that for a reason. The other engine that was in had it working. Im pissed tho ... why would he give it to me like that