bigjohn16678

I'm back again to pick some brains. 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?

oldcutlass

The 1 1/2 turn on your carb adjustment sets idle mixture only. When you set your timing did you disconnect your vacuum advance, if not that would explain the mark being way off. A disconnected EGR will effect the way the engine runs and mess with sensors.

bigjohn16678

I reset the carb just in case it was running too lean (the caps were missing). When I got the car, everything about the engine controls was either disconnected, broken or missing. Yes, I disconnected and plugged the vacuum advance. I'm doing everything by using the service manual. The factory mark on the balancer was not in sight on the timing tab. As far as the EGR valve, it wasn't connected properly anyway and it's the wrong one. I've been driving the car that way without any major problems before the chain was replaced.

oldcutlass

Your going to have to get your engine to TDC for #1 cylinder and see if your harmonic balancer had spun.

bigjohn16678

Just did that today. The mark does come to zero on the tab. That's the strange part. The shop made their own mark too and that doesn't show up with the light. Both the factory cut and the shop mark are on the other side of the water pump when I use the light. I'm not sure if that evidence of a spun damper or not. Since the factory mark hits zero when I bump #1 TDC manually, the damper is where it should be right? I'll have to read the manual again but I'm sure the front drivers side is number 1 cylinder. The book says so.

oldcutlass

The front drivers side is #1. Do you have a dial back timing light? WHat is your timing actually set to right now?

bigjohn16678

I have just a regular timing light. I can say that because I have no idea what a dial back light is. I've had this light for decades and I have an old tach/dwell meter too. My timing is set by ear right now. The factory cut does not line up anywhere near the timing tab. I know the vacuum advance needs disconnected and plugged. The timing according to the manual is to be set at 20 BTDC@1100 RPM.

jcdynamic88

1977 ,what sensors? overheating on the hi-way is a good indication of a flow problem with coolant,also retarded timing will cause it to run hot.i've also seen the centrifugal advance on those distributors get frozen or lazy which doesn't help when trying to set timing.

tru-blue 442

'm thinking that 2 row rad is too small.
Was there a problem with the 3 row?

bigjohn16678

I removed the 3 row a few days ago. I was going to have it checked but the guys who used to do that are all but gone due to EPA regs. I put it in just to drive locally until I could get it checked. When I couldn't find anyone local to check it, I just ordered a new all aluminum radiator. The 2 row will do the trick until it arrives this Tuesday.

bigjohn16678

I cleaned and lubed the weights 2 years ago when I did the tune up. The overheating didn't start until the chain was replaced.

olds 307 and 403

Are you disconecting the vacuum advance and plugging the hose? The vacuum advance can add 30+ degrees. I would make sure that thermostat is opening all the way, at the right temperature. I had a new one that caused me endless grief, replaced and problem solved.

bigjohn16678

Yes, plug the hose and the thermostat has been replaced 3 times. I got the last one from Summit that lets more coolant flow. I'm using a "Service manual" to do everything. Following all the instructions to the letter.

oldcutlass

Set your timing back to 20 BTDC @1100 and lock it down, then set your idle back down to 800 in neutral. Plug in your vacuum advance and see how it does.

bigjohn16678

Just for the heck of it, I'll check the weights again to see if they are free. It's only $20 to replace them.

bigjohn16678

I would if I could. The timing mark on the damper is no where near the light when I try.

MDchanic

Thing 1: Is that your lower hose, exactly as you found it? i.e.: Was there a spring in it?
No internal spring = collapsing at highway speeds = overheating badly on long highway runs.




Thing 2: Please tell us how you found TDC. Did you use a method that is exact (within 1-2°)?
A "pretty close" method could have it out that much.

Thing 3: Have you checked to see whether the cam was timed correctly?
There should be a procedure in the service manual where you measure the lift on one specific cylinder at a certain point in crank rotation to check this.

- Eric

joe_padavano

OK, so this started when someone else changed the timing chain, and since then the timing mark doesn't line up.

HMMMM.

I'm going to guess that the timing set was not aligned properly at installation.

bigjohn16678

That is the lower hose. It did have a spring in it but it blew out on the highway somewhere. I had to get another spring at CJ pony parts. I used the starter bump method and a wood dowel in cylinder #1. The damper factory cut was dead on zero on the tab when the piston reached the top. That's what has me puzzled. Why I do not see the cut with the light I don't know.

bigjohn16678

The engine runs great until it overheats. I've run this car all over and it doesn't overheat all the time. I've even beat it up trying to get it to overheat and it doesn't. It does it when it wants to. I think it's possessed! When it does overheat, it boils out.

bigjohn16678

Before the chain was installed, the timing tab was missing. I had the garage put another one on.

MDchanic

You're SURE there was one in there, right?


Another one from an Olds, right?

Post a photo if you can.

- Eric

oldcutlass

I think you need to get your timing tab issue corrected and set it properly or your engine has a good chance of detonating itself to death. This also may be a contributing factor in it overheating.

bigjohn16678

The spring was there, I installed one myself when I changed the hoses in 2010. I bought it from the only place I could find them, CJ pony parts.

MDchanic

Not the spring. The timing tab.

You say the mechanic put one on.
I trust no mechanic. Sometimes they can be ingenious at installing the wrong parts.

- Eric

bigjohn16678

I supplied the timing tab to the mechanic. I got it from an old friend in the engine rebuilder business. I had one from a guy on this site but I wanted one from an Olds 403. My friend had one and sent it to me.

bigjohn16678

I agree 100%. This engine has been overheated too many times. Once is too much in my book. It has been overheated too much twice, it ran on after shutting it off. All the other times, I caught it before it got too hot. Every time I shut it off when overheating, it boiled out.

MDchanic

Okay. Just trying to eliminate the "simple" stuff.

The next step would be to use a very accurate method, such as a dial indicator or the "bolt-through-an-old-spark-plug" technique to ascertain exactly where TDC is. Using a dowel or a screwdriver in the hole can work well, but, because of the number of degrees when the piston is very close to TDC, they can sometimes be misleading.

Also, you say that the timing groove on the balancer is on the passenger side when you are checking the timing and the engine is running well.
This is the advanced direction, so it should contribute to running cooler, not hotter, if, in fact, the timing is off.

Another question: Are you sure the engine has the right vibration damper?
A damper from a '64 will read on the passenger side when the timing is right (but confirming TDC will eliminate this as a possibility).

- Eric

bigjohn16678

I checked the distributor weights this morning and they are free. Just to be safe, I cleaned the old grease off and put new grease on them. I had an extra of the little tubes that come with reman distributors. I'm beginning to wonder about the distributor, could something like the gear slip? Is that even possible? Those gears just go bad, not slip around right? The gear, isn't it installed with a roll pin? It looks like it is the original distributor (AC Delco module) and the car has 129K on it. I rechecked the timing with the light and it's the same story, the factory mark is on the other side of the damper with the light. What I did find was interesting. I wiped the damper off and found what looks like stitching marks on it. Once I put the light back on it, the stitching mark does hit the light. Maybe the notch on the damper isn't the real factory mark? Could this be a magic moment? I will try to take pictures of all three marks on the damper. The cut mark, the mechanics mark and the stitch mark. Looks like rain ATM, so I'll try later.

MDchanic

The distributor gear can't slip, but if it did, your timing would be off, and when you reset it, it would be right again.

You have a problem with your timing reading wrong while your car is running right.

As I said before, I would confirm that the timing chain is set correctly as well.
Instructions are in the CSM for earlier models - don't know about a '77.

- Eric

bigjohn16678

I'm not sure of anything with this engine. I am sure it didn't overheat before the chain was installed. As for the damper, I have no idea if it was ever changed. There were many sizes used on these engines. How do I check if it's the right one? Remember, the mechanic did put his own mark on the damper but that mark is even further away from the tab. He put a blue mark on the damper and a blue mark on the tab at 20BTDC.

MDchanic

Which is why, unfortunately, you have to verify everything from scratch.


Which is why verifying cam timing is essential, one way or another.


I have no idea, while it's on the car (unless you could see the keyway with a mirror).
... But Joe Padovano would.


Which is highly suspicious for something being way off.
Good mechanic or bad, he should NOT have had to do this if all was well.


Another question to ponder:
What is the possibility that the mechanic left some sort of glob of sealant in a cooling passage when he reassembled it, and this glob is able to move in such a way as to block something, then unblock it?

- Eric

bigjohn16678

I've been told the mechanic could have been overzealous with the sealant and could be intermittently blocking the coolant flow. I might have to pull the water pump and take a look. I got a new radiator coming Tuesday. I'll pull the pump then.

Kennybill

What Eric said about finding TDC, X's 2. Very easy to be off a tooth on the chain. Probably something connected to the replacement of the chain/water pump. I would start with checking TDC. Ken

MDchanic

In which case, if you can get your hands on a balancer puller (probably available as a "free rental" from your local chain auto parts store), you "Might As Well" pull the balancer and have a direct look at the timing chain and marks, and get a picture to post up for us here.

At TDC, the keyway should be at about 1:30 and the dot on the crank gear should be at 12:00.

Note that this is NOT a substitute for accurately finding TDC.

- Eric

M-14

I'd have the coolant analyzed for exhaust gases in it. When certain gases get put under pressure they expand a lot, causing the hoses to blow or pushing coolant out into the overflow tank.

Octania

"The overheating didn't start until the chain was replaced."
================

At which time the timing was altered perhaps and the WATER PUMP REPLACED.

Were the pulleys changed?

Do you have the previous water pump to reinstall?

It should have been the ubiquitous "#4" pump- but originals have a better cast iron impeller. Different pulleys than the factory used can alter the speed of the WP and thus its performance.

I also agree that because timing can greatly affect overheating, and you do not seem to have a handle at all on your TDC marks and such, it would be BEST to gain access to the cam timing set, absolutely verify a tdc mark with the positive piston stop method, verify timing set is correctly installed, check the cam event timing while you are in there...

As for your timing mark appearing about 90 degrees CCW of where it should be, that indicates to me that you are using #2 or #3 wire for the timing light, which fires 90 degrees before your balancer's TDC mark should be at 0 to 25 or so on the 403 type plastic timing tab on the LH side of the engine.

bigjohn16678

If the timing chain is off by one tooth, wouldn't the engine run like crap? It has more power than before the chain was installed and runs better in idle too.

Octania

No, not really.

Former bossman had a cheby truck jump a tooth due to worn parts. Started and idled perfectly, but low on top end, as I recall. Like NO top end power...

18 & 36 teeth if I am not mistaken, so one tooth would be 1/36 at the cam or 10 degrees or 20 crank degrees.

"The #1 cylinder is the drivers side front according to the service manual."
===============
So sayeth the huge numerals on the intake runners also. People still get ahold of the wrong wire, or it's in the wrong hole on the distributor etc.

bigjohn16678

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. I know for a fact the cooling system does not leak. 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...