403 Olds in a 77 Buick Electa overheating

My 403 is overheating. First the story of how it all started. In July 2011, the chain went and I had a "reputable" garage install a new one. I've been driving the car almost everyday since Nov 2010. Before the chain was replaced, the car ran great except for the sloppy chain. After it was installed, the car overheated the very next day. It boiled out! My thinking at the time maybe there was air in the system. I filled it back up and had no problems until August 2012. We were on our way to Harrisburg, Pa from Johnstown, Pa for a family reunion. The car overheated in Shippensburg. I let the car cool, filled it back up and the rest of the trip was uneventful. When we got back, I back washed the cooling system and refilled it. Then on July 3rd, 2013 we made a trip to pick up a small trailer. We got about 20 miles when the idiot light came on. Before I could find a safe place to pull over the lower hose blew up! I'll post a pic is I can. It scared the crap out of both of us, it was that loud! I phoned a friend to bring a new hose and coolant. We didn't get 5 miles before the light came on again. We had to have the car and trailer towed from the highway. That hurt $$$.
Now, what I did to try to fix the problem.
The water pump is new (not a reman) and was replaced when the chain was done. I installed a new HD clutch fan, thermostat OEM temp, all new hoses, belts, oil change and all the filters.
I tried to set the timing but the factory mark doesn't even come close to being near the timing tab. I tried setting this to the OEM mark and it ran like crap spitting out the carb. I did set it by ear and listened to the engine while driving to be sure it was not pinging. The emissions vacuum parts are also new and I used a diagram from the service manual (Not a store bought one) to route all the lines. Everything was missing or broken when I got the car. The only thing not hooked up is the EGR valve. The wrong on is on there, I just plugged the lines and capped off the vacuum line.
I swapped out the 3 row a few days ago and installed a 2 row only because I wanted to try to eliminate the rad in case it was the problem and the 2 row was on hand. I have a new aluminum one on the way. I don't know if this may be a clue but it seems to overheat when I'm traveling on a highway at 65MPH. It has not overheated on any back roads or short 10 to 20 miles trips. I also installed a temperature gauge and got rid of the idiot light.
If I had any hair on my head, I'd have ripped it out already. I triple checked all my work and the fuel mixture was set the old way. seat and 1 1/2 out. I even did the balloon trick over the rad to check for exhaust leaks into the cooling system. The balloon remained limp most of the time and when it did pop up a little, I did not feel any "pulsing". Anyone have any ideas?

 

You may not want to hear this, but it sounds a lot like they messed up the valve timing when the put the chain on. Big clue is the timing marks being off so far. Reputable shops aren't always perfect, the "good" mechanic might have been out sick that day. Good luck.

 

X2

 

I had some overheating issues .
They went away after the timing and idle was set right.

with a 2 row radiator ,
at 65mph the coolant is not staying in the radiator long enough to get cooled off....

oh, Welcome to the forum !!

 

Timing chain improperly installed x3.

Devon

 

Thanks for the welcome!
The 2 row is just temporary. I haven't attempted highway travel with the 2 row. Just around town. I have an all aluminum on the way.

---------- Post added at 06:30 AM ---------- Previous post was at 06:28 AM ----------

I thought that too but the factory cut comes around to zero when I bumped the starter to TDC. That's the part that's driving me crazy.

 

Set the total timing to 30 degrees with a light without the vacuum advance connected.

 

Tried that, the manual says to disconnect and plug vacuum advance, set timing, 20@1100. I would set it if the mark was visable on the tab with the light. The damper mark is on the other side of the water pump, pass side of the engine when I use the light, not on the tab at all. The tab and mark line up to zero when I starter bump the engine to TDC. The mark is no where near the tab when I use the light.:af:

 

Don't let it drive you crazy! All you did was check the balancer TDC mark against actual TDC. That has absolutely NOTHING to do with checking cam timing! You could have done the same check with the camshaft and timing chain sitting on the work bench and come up with the same result...think about it.

To check cam timing you're going to have to pull the timing cover. You need to know the relationship between crankshaft position and camshaft position, and it may just be so simple as having the gears a tooth off.

Devon

 

X2 think about it... You say the over hearing didn't start until the timing chain was replaced. That's a good place to start b4 more over hearing occurs.

 

Is it possible to check the relation between the cam and crank another way? Maybe with the valve covers off? I have bad luck when it comes to installing timing covers. Twice I had an oil leak when I finished on another project.:idea2:

 

Yes, with a dial indicator, a degree wheel and most importantly, the actual camshaft timing specs (cam card).

This is what should be done on any camshaft install. Some errors do happen when a new cam is ground, and "degreeing" the cam during installation is the only way to know what's up. It's entirely possible that your timing set is installed correctly, but the cam was ground improperly. Degreeing it will confirm or rule out cam timing as a potential cause of your symptom.

See: http://www.v8buick.com/showthread.php?220945

Devon

 

X-4 or 5, or where ever we are with this. It's definitely the timing set in wrong. Bite the bullet and take it apart. The 403 isn't that difficult to tear down. Case of beer and a couple of wrenches should do it...

 

It would be 5.
My guess was timing, too.

 

I'm still on the fence with taking the timing cover off. The 403 is known for the cover to wear away around the coolant holes. Once I get another cover, I'll give it a shot but I have a question. Why does the car overheat intermittently and not every time I hit the highway? After every overheating instance, I would fill it back up and finish the trip without a problem. I would think if the timing chain wasn't installed properly, it would overheat all the time. Today for instance, I drove about 7 miles on the highway up the mountain. The temp never got over 200. It got close but dropped back to 190 quickly. I was even pushing the car past 70 when it got close to 200. No problems either way. This is what keeps my mind busy and awake at night.
I was supposed to swap the rad today but there was a shooter running around the neighborhood just a few blocks from my house, so I put it off. I bought an all aluminum, welded rad, no plastic. I decided to start tomorrow. I'm going to pull the pump to check the impeller and see if the mechanic got overzealous with the RTV sealant. The pump was new, not a reman and was installed with the chain. Does anyone think I might be better off with a reman?? I got one on order just in case. Maybe I should compare the impellers too?? I'm almost willing to try anything at this point. Pulling the timing chain cover will be a last resort. My luck with covers while the engine is in the car is 0/8. My hands don't work like they used to so I'm 99.99% positive pulling the cover will not have a good outcome.
Did you ever wish there was such a thing as an honest mechanic? I'm sure there are some out there, I just haven't found one. I would take the car to a mechanic just to check the chain but they do not like being told what to and not to do. I'm glad I keep a close cut head...:laugh:

 

Might it be the thermostat? Maybe sometime it sticks closed?
That might explain the intermittent overheating (?)

Just a thought.....

 

I changed it 3 times. The last one was from Summit racing. The high flow type.

 

X3. The good news is that the Olds is a fairly easy timing chain to replace.

---------- Post added at 10:37 AM ---------- Previous post was at 10:35 AM ----------

The chain could be 10 teeth off and the mark would be right on. The piston, rod, and harmonic balancer are all connected. The valve timing only is affected by the chain.

 

That's right, what am I thinking. I'm still stuck as to why it overheats intermittently. Wouldn't it overheat every time? The day before we picked up the trailer, we drove all over looking at trailers. We put about 200 miles on the car, no problems. Not even a slow crank to indicate it was running hot and we made many stops. That's another thing driving me crazy. Just when I think it's fixed, it overheats again.

 

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. :TU: 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.