Help!!! 62 Olds Starfire overheating problem and brake problem!

[viper771]

Hello everyone! I bought a 62 Starfire hardtop last summer but have yet to put it on the road yet since it needs some bugs worked out. I hope that some of you guys can give me some pointers so I can at least drive it around the block sometime before winter decides to hit SW Ohio.

Anyway, since I got the car it always ran hot. I am not sure what the problem is exactly. It overheats rather quickly, with the hood open and no air cleaner on. I think sitting at idle, it gets very hot around 5-7 mins of running. The guy I bought it from put in a new thermostat. I ran the car with the rad cap off to see if I got good flow from the water pump and I did. Upper/lower hoses are newer and lower has the spring in it so it isn't going to collapse. The radiator was recored very recently and is looks very very clean on the inside. I am not sure what is wrong. At some point thte dual exhaust was taken off and single exhaust was put in (I figured that it was to save money and so the weird bends for the drivers side pipe wouldn't have to be dealt with). I do plan on putting the dual exhaust back on, but at this point I just want the car to "work". The heat risers spring was disconnected, but I am not sure if it is stuck open or closed, or maybe just part way open. I took a picture of it, hoping that someone could let me know if it is open or not. I don't have anything to compare it to. I have been soaking the nuts in PB blaster but it won't be easy getting at it, so I was thinking maybe something else could be causing my problems? I just put new R43S plugs in it. The fuel pump is new/rebuilt. All fuel lines are new (both steel and put in fuel injector line). I bought a new heater core and plan to flush the system, put in a new water pump for good measure, drain the block via block drains as well, and see if that helps any. I read that a car running too lean could also cause overheating. But any answers would help and I am a total newbie when it comes to the mechanical aspects of old cars.

As for the brakes... they were redone before I got the car. The problem is the brake pedal returns very slow and the brakes and the car stops too well when you barely push the pedal (almost sending you right through the windshield) when I am driving it in the backyard. Now, the orig master cylinder and booster was replaced. However, I am thinking the booster is the problem since it looks like some kind of generic type. I don't know if having the orig style inline check valve along with the check valve in the booster is adding to the problem or not. I am just thinking that the rod from the booster to brake pedal is too long, which is causing some of my problems. I did find an orig booster and I plan on getting it rebuilt. Any other ideas what it could be?

Take a look at the pictures. Any help would be very appreciated!! I do have both 61 and 62 shop manuals, along with the owners manual. All I ever do is research this car and I am getting to know her inside and out.

[Tedd Thompson]

394's are notorious for their heads cracking and causing heating problems. Do you see any bubbles coming from the radiator spout? Is the clutch fan working properly?( it may not have a clutch fan it been to long since I had a 394 ) Just a few thoughts ..Tedd

[viper771]

I have heard that about the 394s as well. I don't know much about them other than what I have learned since I got the car last summer. When you mean the spout, do you mean from under the radiator cap, or the overflow, or when the cap is off with engine running? I think only cars with AC had the fan clutch. Mine doesn't have AC, which I should have mentioned in my post. I was thinking it may just be as simple as a heat riser rusted in the shut or almost shut position. Since the car only has single exhaust, that would cause a lot of problems. Taking that thing out to make it into a spacer won't be easy. The nuts look pretty rusty on the driver side and the bolts that go through the exhaust manifold on the pass side look worse (the threads are nothing but rust). At least those aren't such a big deal since you can just replace the entire bolts without trouble. The drivers side...... hopefully I won't break any bolts off or mess up threads getting the nuts off. I just wanted to look at other options before I go messing with it, like the timing, which I do not know what it is set at yet. Need to get a timing gun and dwell meter still Thanks for the info!

[D Yaros]

SW Ohio? Did someone say SW Ohio? Where? I used to live in Cincy.

I have more questions than answers for you. Before I start asking, let me state that I do currently own a 1962 Oldsmobile, Dynamic 88.

What leads you to believe the engine is overheating; what signs/symptoms of such have you experienced?

Does the HOT light on the dash illuminate after the engine has been running?

What is the rating, in lbs., of the radiator cap?

What is the temp rating on the thermostat?

Does the heat riser counter weight move at all? I take it does not.

I will tell you that the 394 c.i. engine does generate a lot of heat; so much so that most folks would touch, or pop open, the hood and immediately think the car is overheating, when it is not.

The proper radiator cap is one with a 16 lb. rating.

The proper thermostat is one with a 160 degree temp rating

The heat riser valve is not of much use/value to you. It's function is to speed up warming the engine on a cold start in frigid temps. I assume you are not driving the car in the winter. If not, then your best bet is to force it open.

I must also assume the valve is open at present. Think about it, if the valve was stuck closed on a single exhaust system you would have little to nothing coming out the tail pipe at any rpm.

My advice is to change the thermostat, flush/drain the system (including use of the block drains as you indicated) and make sure you have a proper radiator cap. Then, let's see what happens?

[viper771]

Thanks for the info D Yaros! I live in Middletown actually, which is about an hr from Cinny. My wife works at the UC hospital there. I am from California originally and my wife is from the Van Wert area of Ohio (met in the military). We are still exploring this area and so far it isn't too bad.

As for the heat riser, no it does not move at all. When I located it during my fuel line change out, one side of the circular spring wasn't connected to anything. There is stuff coming out of the tailpipe, but I was thinking maybe the valve insde isn't open all the way or maybe flapping around. It was just something I could think of that would cause my problem.

Yes, the hot light does come on the dash after a couple minutes of the car at idle and the hood open. The exhaust also smells kind of funny, if that has anything to do with high heat. I checked the pressure cap and it is a 15 or 16 lb cap. I was going to replace it anyway when I put in the heater core and do the system flush. The thermostat was replaced prior to me getting the car. I want to say it is either a 160 or 180 thermostat. I was going to replace that as well since I bought a new one and it is 180 degress as well (I will have to check it was almost a year ago when I bought it). I figured I might as well put in a new water pump too since they aren't too expensive and the system is going to be drained. All hoses look good and are new. I figured the thermostat worked since there was good water flow in the radiator (i left the cap off, ran the car, and saw the coolant begin to move very quickly). Also, the top rad hose becomes VERY HOT.

I think one of the reasons why I was thinking it was overheating (besides the HOT light coming on) was that I could see either blowby or some exhaust coming from the oil filler cap (it comes out of the downdraft tube but that is normal). I was just hoping that it isn't something serious.

How do you suggest I flush the cooling system? I was thinking of draining it, adding some Prestone rad flush, redrain when cooled off at block and rad, then add some vinegar or clr with water to it, reflush, and then put some new 50/50 Prestone in it? Never done this kind of thing before. I am just learning as I go I would rather learn it all myself than just take it to a shop to have someone else take care of it. You don't learn anything that way.

[rocketraider]

I would do two things-

First get a radiator thermometer and put it in the filler neck with engine running and coolant circulating. That will tell you actual coolant temperature. You should be able to find one at a good auto parts store.

Second- from experience, the temp sender units for these cars can be troublesome. They have both a COLD and HOT terminal (check to see that you do in fact have two terminals on your switch, new replacement stock often does not have the COLD terminal) and I have known many of them to expand and ground against the switch body prematurely, lighting the HOT lamp. I had one on my blue Starfire that would light the HOT lamp almost before the COLD would go out.

[viper771]

Hummmmmm I think the temp sender unit was replaced on my car actually. There is new teflon on it. I will look for one of those radiator thermometers when I get some radiator flush. If my car really isn't overheating, that sucker get SUPER HOT then. I will have to check the timing too. I think it is set at 7 degrees BTDC, since there is a white mark on the balancer on that notch. I will find out for sure and check the switch while I am at it. If the switch is faulty, does Fusicks sell the correct one? Very good info!!! That does point me in the right direction.

[viper771]

here is an update:

I do have an older temp sender unit with 2 prongs on the top that the connector pushes down on. Maybe it is faulty?? The reason I was thinking that my heat riser was closed or semi closed was that it looked like it was in the closed position when I compare it to the heat riser valve shown in the 61 Repair Manual. My heat riser arm and the one shown in the book, look like they are in the exact same position.

I forgot to mention this but when I blip the throttle, the car acts like it is going to cut out and die. I don't know if that is from me messing with the idle adjustment screws at the front of the carb or what. Those screws were WIDE OPEN when I got the car and the fuel pump was leaking. After I fixed the fuel pump I tried to get the idle down a bit and hoped maybe it would help the overheating problem. If anyone had a picture of a heat riser valve in the open position (since mine is frozen), it would help me have something to compare mine too.

Thanks again for the info thus far. I will put in an order for a new rad cap this week and get other stuff for the upcoming coolant flush!

[D Yaros]

On the heat riser: Spray it daily with Power Blaster or something similar. Hopefully it may free up to the point you may be able to move it by hand, eventually.

On the flush: I recommend you back flush the engine. First thing to do is drain the system. You may find nothing comes out of the engine block petcocks when opened. If that is the case, stick a wire in the petcock opening to unplug it/them. Then add water and your chemical flush. Let the car run for some time, not just to the point of warming up.

When flushing, make sure you have the heater ON! To back flush, remove one of the heater hoses and stick the hose in the end of the removed heater hose. Keep the water going until you get steady/clear discharge stream. You may have to drain/flush more than once.

As for the carb, the screws you are referring to are air mixture adjusting screws. Start the car, let it warm up, run at idle. One screw at a time, screw in until engine starts to slow. Then back out 1/2 turn.

Believe it or not, I actually lived in Middletown in the early '70's.

[viper771]

You must have lived in Middletown when things were still semi good in the old part of town. Things are getting somewhat better in the old downtown area but it could go a lot faster.

As for the heat riser that isn't a problem. The guy I bought the car from never drove it or had it running for very long. He just fixed it up after he decided he wasn't going to use it as a parts car for his 62 ragtop. I will spray some PB blaster on it and I hope it frees itself up. The exhaust system that is on there now has been on there for awhile.. I would say a good 10-15 years by looking at the stuff. If I do stick a hose in one of the heater hoses, will I have to do anything with the heat valve on top of the engine? I know vacuum opens it or closes it but I never encountered anything like it before. As long as water can force past it I guess. I am going to see if I can pick up a timing light and dwell meter so I can actually check the timimg for once on my old cars. Any suggestions as to what brand or anything?? Thanks for all the help so far. I really want to get my car on the road at least once before winter hits!! During the winter I can work on putting the headliner back in or messing with the suspension.

[D Yaros]

As long as you have the engine block petcocks open there should be no probs with the heat valve when doing a back flush.

On the timing light and dwell meter, I would go with a brand name, not some Chinese Cheapo.

[viper771]

Alrighty I need to get some supplies together then. I will look up some dwell meters and timing lights. I could use them on my 442 as well. I will keep everyone updated! Would you say that 5 degrees BTDC is good, or is something else better due to the crappy gas? I only use premium and put some lead additive in there... but I am sure the gas still isn't as good as orig premium from the 60s.

[D Yaros]

I would be going with the factory spec on the timing, and go from there. Yes, the gas is crappy, but for reasons that have nothing to do with the timing setting.

[viper771]

Alrighty! I found a good deal on a digital timing light that also does dwell too. After I get the necessary supplies I will do the cooling flush. I checked under the distro cap and everything looked good. Everything looked fairly new. Some people say to change the timing a bit bec of the gas we have today, but I will stick with everything stock and then we shall see what happens. Thanks for the heads up!

[Steve Westlake]

These are photos of NOS heat riser valves. Both - two bolt and three bolt for single and dual exhaust. I am not sure which one you have on your car so you should be able to figure out if yours is open or closed. Hopefully this helps.

Oldskeeper.

[viper771]

THANK YOU VERY MUCH!!!!! I have the 3 hole version. If you notice the one picture of the valve full open, the weight on the side it actually touching the arm that the spring attaches to. My weight is more of less perpendicular to the valve body.. (see my image) So it isn't fully open, or fully closed.. which is adding to my overheating and I get a lot of exhaust out of the top end after the car reaches temp. I will have to soak the bolts in PB blaster so I can hopefully get it off without busting anything.

I am taking a break from the car for a couple days since I just spent the last couple days under the dash replacing ALL of the vacuum lines to the heat and ventilation controls. I even rebuilt the master dash controls....yet my heater blower doesn't want to turn on without me pushing the diaphram in the engine compartment.. I think I put the heater control switch back together wrong (I didn't mark anything before taking the 2 halves apart) so back under the dash I have to go. What a pain in the butt!!! Thanks again for the pictures!! At least I am more sure that the heat riser is actually causing the vast majority of my overheating problem!

[sysmg]

You really messed up the idle mixture screws. They are not the idle speed setting. Hopefully you didn't screw them in really tight and damage them. With the car off, turn them all the way in (gently) until they seat. Then loosen them 1 1/2 turns (make sure you do this exactly by noting the orientation of the slot in each screw). Note: as you loosen, every time the slot is in the same position you have loosened it 1/2 turn. 1 1/2 turns is a good starting point. Both screws need to always be adjusted the exact same amount (ie. 1 1/2 turn). Once you have the overheating sorted out you can adjust them further (I wouldn't run it too long if it is getting as hot as you say). If it's running too fast adjust the idle speed screw, it's one screw (on a tab on the side of the carburetor or on a cam on the outside of the carburetor) , usually near the side of the carburetor where the rods from the gas pedal hook to the carburetor. It kind of stops the return spring from completely closing the throttle plates.

To further adjust the idle mixture screws you have to understand what they do, basically they are tapered screws that as you loosen them allow more gas into the air/fuel mixture. Tighten them and they reduce the fuel. For the car to run properly these have to be adjusted exactly to get the best fuel mixture. These are idle mixture screws, as they affect the mixture when the throttle is closed or close to closed. They have a huge impact on smoothness of idle and how the car moves off from a standstill (under normal driving when you gently squeeze the gas pedal). If they are completely closed the engine won't idle, because it isn't getting any fuel. Theoretically, as you open them (say 1/4 turn or 90 degrees at a time, first the left and then the right), from close to closed, the engine will speed up. After a few iterations of opening them more (again 1/4 turn at a time) the engine will no longer speed up. Keep going and after a few iterations the engine will actually slow down (called rich fall off). Then if you started to screw them in the opposite would happen, and after a few times, when the engine slows down as you turn them in you've reached lean fall off. Basically you want to find the lean fall off point and then loosen the screws 1/4 turn from that point (you can play plus or minus 1/8 turn from this point if you really want to get it perfect).

So to actually make the adjustments, I'd recommend hooking up a tachometer so you can see the actual engine speed. Start the car at idle, turn out both screws 1/4 turn, to make sure the engine doesn't increase in speed, if it does loosen the screws again another 1/4 turn. Repeat until the 1/4 turn doesn't make much difference. Now you want to turn both screws in 1/4 turn at a time, repeat until the engine starts slowing down noticeably. Once it slows down, loosen the screws back out 1/4 turn to get to the last point where the engine had not slowed down yet (this is the lean fall off point). Now loosen both the screws another 1/4 turn. This should provide you with a very good idle mixture setting. Now adjust the idle speed as per the factory settings using the tach. This should provide for a very good idle mixture. It should take about 5-10 minutes of idling (which is why I'd recommend waiting for this final adjustments until you fix the overheating (start with just them each loosened 1 1/2 turns from seated). Drive the car and check how it accelerates normally with gentle throttle from a standstill. You want to minimize hesitation when you accelerate and for the car to move off smartly. To try and optimize the settings, you can adjust the screws either in and/or out by 1/8 turns and test drive to see if it improved. Remember to always keep them the same number of turns. Good luck. As for the fine adjustments, running with them turned in closer to the lean fall off point will get better gas mileage but poorer acceleration, further out will reduce gas mileage but improve acceleration. All of these fine adjustments happen within about 3/4 of a turn.

Edited July 30, 2012 by sysmg (see edit history)

[viper771]

Thanks for that info!!! I just ordered a Equus 5568 Pro-Timing Light so that should help me out quite a bit. I figured that the idle mixture screws were messed up. When I got the car, they were unscrewed almost all the way out!! I tried to get them as close to spec as I could at the time. The fuel pump was leaking and the carb was a bit leaky...so I was doing damage control for the time being. I still need to get a carb rebuild kit from NAPA since the rubber plunger is rotted and I think the top carb gasket is kind of weeping. The carb was rebuilt recently but I know the top plate wasn't screwed down very tight. I hope to just put in new gaskets (new to the whole carb rebuilding thing) and fix the rotted plunger.

If I can't get the heat riser valve to move after a few days of soaking it with PB blaster, I will end up just taking everything apart, drilling out the valve, and hopefully put everything back together. I have new exhaust flange gaskets and what not so I am hoping that things do go well. I really appreciate the carb info! You can find all kinds of info about quadrajets, but not a whole lot about these earlier carbs. Once I attempt to get things fixed, I will update everyone on the progress.