Try the rad and check the water pump impellar and rtv job. How many core is it and same size? I had everything go against me on my 403, bad new thermostat and under drive pulleys were the main cause. You have a 7 blade fan, correct? Sounds too intermintent to be a chain issue but could be advanced a tooth. Remember multiple key way crank gears do exactly that. I have mine set on the advanced triangle on my Cloyes set, will soon see how it runs soon.

 

Do you have an overflow tank on your radiator? What temps is it getting to when you say it's overheating and spitting coolant?

 

Yes, I have an overflow tank. I just put the gauge on last week. It hasn't overheated with the gauge on yet.

 

Ok, lets go back a bit. Is the overflow tank filled to the proper level? When it overheated, what exactly did it do? If it were prone to overheating it would be easy to duplicate the situation.

 

The rad would boil out the overflow tank. The tank is always at the right level. I check fluids every time we go out. "Full cold" before we start out and "full hot" after.

 

I finally made it back. I didn't disappear, we just had 4 grandchildren dumped on us. It's a tough adjustment. Anyway, I found an engine and it's looks clean. I need an intake for it. Anyone have one or can point me to an OEM intake? Money just got real tight. Looks like I will be nursing this engine over the winter. I hope to get the other engine in when the spring comes. The engine hasn't overheated yet. The temp still stays below 190. I've even beat it up a few times without the SO in the car. That's the only way I can beat it. No problems yet.

 

So far so good.

 

Keep an eye out for an A4 aluminum intake, pre 85 307's had them. Cast iron 4bbl intakes should be free. What is wrong with the 403?

 

Well, I'm taking the best way out I know how. I got a 403 engine nearly complete. Just the intake is missing. I'd like to get another one, anyone got an OEM 403 intake? I'm going to put the engine on a stand and make sure it's right before installing. With money tight and winter fast approaching, I may have to nurse the engine over the winter. I hope to get it in before the snow flies, it doesn't look like that will happen. If I get an intake cheap, I might be able to get it installed. We got 4 grandchildren dumped on us Aug 7th. Great kids but it's going to be tough to come up with the bucks when I'm on a fixed income. You can bet I'm going to check the old engine timing chain to see if that's what has been causing the overheating. I'll be back after the other engine is installed.

 

John, I feel for you.
I was reading back through all
the posts and I didn't see anywhere
that anyone suggested a new radiator cap.

Just a thought, but maybe a 16 lb. one would
do the trick? We all just maybe overthinking the problem.
I hope all works out for you and your family as well.

 

I changed the cap three times and the thermostat three times. I'm just going to change the engine and be done with it. I will take the old one apart to investigate. I will check the chain and look for obvious head gasket failure. I remember when I got the car, it had sat for 3 years and the rad was full of rusted water. It could be a small crack that only opens when it gets run a long time. Yup, this engine is coming apart when it comes out!