A search turned up zip on my motor.
My 331 is still heating up at stop and go traffic. I'm going to attempt to flush the block myself. Last year done with radiator.... Long story. Replaced lower hose, etc. So Last year took Radiator to shop where they do their acid? Boil? To remove scale. Reinstalled, and same problem. Basically went onto other things. Now I'm back to it.
Now to the block, how is a scale flush/cleaning done? The car is running. Locate and remove freeze plugs? How easy is it to remove and install new ones, is it recommended? I've heard back in the day of using baking soda, acids, etc, buddy said use Evapo Rust.
I think my Rad is a two row, can my radiator shop install an extra row or two? So I can keep it looking original.
what is recommended here?
Thanks, Mike
Hello Mike,
Other readers can correct me if they have other ideas.
Mine is a 1948, 346ci flathead. Notorious for running on the hot side.
I used a commercial flush (perhaps Prestone) ran it about 1/2 hour, then opened petcock and continued to run garden hose water until it came out as clear as the water going in. Did this twice about a week apart.
It helped a LOT!
Depending on the condition of your hoses and heater cores, if they are in good to new condition, you should have no problems with leaks after. To be on the safe side, you may want to temporarily bypass your heater core/cores. If the hose/hoses leak after, they probably need replacing anyway.
After I did mine twice, I was stuck in traffic for an hour with the outside temp at 92-95 degrees and had no problem.
Good luck, Richard
I'm going to assume that this is a original engine that has not been rebuilt.
Most cars will run hot in stop and go traffic. You didn't say if it was puking the coolant out, or just running hot.
These are some other things that will cause a hot running motor in traffic.
Old radiator cap. Wrong poundage reading on cap.
Spark timing. Is it set correctly.
Vacuum advance. This is a big one. A vacuum advance that isn't working will keep the car retarded , causing it to run hotter at idle.
Plugged exhaust system.
Bad heat riser. Stuck shut.
Bad thermostat, or missing thermostat.
Belt slipping.
Bad water pump.
Out of all of them the timing to me is the biggest one , then run down the list from there.
Since I dont know the history of what was done, these would be what I would check.
Roy
I will try the block flush. Look around and see if Preston's still has a flush. Heater core is bypassed.
I dont know engine history prior to my ownership last summer. Just running hot as far as I can tell.
How can I tell if the vac advance is working?
Those are helpful Roy, and I will run em down. Thanks, Guys
Do you have a copy of the Shop Manual? There should be 2 brass drains on the sides of the block, one on each side. To be safe, don't try to remove the plugs if they are in brass fittings. You should see two 45 degree angled fittings like those used on your fuel and vacuum lines. Remove the fittings with an open-ended wrench, not the plugs. I say this because I had a fitting break once because I tried to get the plug out...
Chances are there is so much crud in the block that nothing will come out. Use a piece of wire, small screwdriver or an awl to carefully break through the clog and open up the drains. You'll be amazed by what comes out of the block. Cleaning the radiator is only partially effective. You don't want all that crap going back in your radiator.
One way to check the advance is with a vacuum pump. If it holds a vacuum, it should be working. If not, it needs to be replaced.
Yes I have the shop manual. I will do that as well Walter. Leave em open when flushing should push most of it out of the block and away from Rad. If nothing comes or very little clean out. Gotcha.
No vac gauge. Will find one.
Do you have a timing light? You can see the timing change with the advance connected and then disconnected with the vacuum port blocked off. If the light shows the same level with it connected and disconnected, it's bad. If it is working, you'll see your timing mark change on the balancer as you increase rpm. Itill show that it is working but it could still be leaking slightly. The vacuum test is a better indication.
Walter, is that a ported vacuum on that car.
I ask because you said to increase the rpm to see if it advances. If the vacuum is in the intake it should jump right up, on the timing.
Roy
I do have a timing light somewhere. Will dig her out. So basically if I have movement then vac advance should be good.
I did discover a 1/4" copper line running from rt rear exhaust manifold up to my carb. I'm sure I've read somewhere this should be disconnected?
Mike,
What you want to do is remove the line from the vacuum advance and put some tape over the end of the line to block it off.
Set up your timing light and take a reading of the timing mark.
Then install the vacuum line back on the vacuum advance and take another reading. Timing mark should jump up , BTC.
Sounds like it is a direct connection to the intake manifold , so you should be OK.
Some of the newer cars had the line coming off the carb above the throttle plates. There is no vacuum on these until you open the throttle.
So, you should be fine.
Roy
I think the line running from rightt rear exhaust manifold up to the carburetor is to provide heat to open the automatic choke when the engine warms up.
Is cylinder #1 front left (driver) side?
Edit: just found in manual. That is #1 front left
That's #1 cylinder--front driver's side. As for the vacuum advance--with it disconnected and taped off and using the timing light (which now would be a good time to find your timing marks), the timing will move off your idle slightly. That's the mechanical/centrifugal advance (the springs on the distributor plates) kicking in. It'll reach a point and not change any more. With the vacuum advance connected and, if it's working, the advance will go beyond that mechanical advance point.
With timing light hookup, I get zero changes wether I plug advance itself with my finger or not. Pointer looks to be about an inch above the A line. Appears no change at all. Should I conclude the advance needs replacing? If so, will Napa carry?
Thanks, Mike
Oops, missed the part about the exhaust manifold.
Follow the line back from the vacuum advance to where it connects. Should go to the intake manifold someplace, or if it is on the carb, it should be below the throttle plates to get the reading on it for advance.
If its above the throttle plate then you might not get a reading. Not familiar with the older Cadillac's and there connections.
You also dont want the engine running fast if your checking timing. Weights will swing out and advance the timing on you.
Roy
You dont want to plug the advance unit. You want to plug the line , or you will have a vacuum leak.
Where is it connected to on the other end?
Roy
Your manual should tell you where the timing mark should be set. It should go through the whole procedure for you .
Roy
I tried her both ways. Plugged and unplugged advance itself, then the line, no movement at all.. The advance vac line goes under intake and around into front of carb.
I consulted manual. Should be set at the A mark, but if advance isn't working should I wait until I get it operational?
Also, with electronic ignition should timing still be set by the book?
Thanks, Mike
Again, does it plug in above or below the throttle plates, or the throttle shaft when looking at it.
You may have a plugged line or plugged carb, but I need to know where it plugs in.
You can set the timing on the car, if you have it running at a low rpm.
Then find out if the tube is blocked on the vacuum line.
Roy, It's located on the very bottom of carb, in center, just above the intake manifold.
Do you also have a dwell meter and tach? You'll need to find out what rpm your engine is idling at. If it's too high off the bat, then the mechanical advance will always be in operation. You have to get the timing set right--usually somewhere around 450-500 in "Drive", choke fully open and make sure the high idle cam on the carb isn't stuck. Timing needs to be set with the advance disconnected and the vacuum source plugged. If you removed the line from the carb or intake, you need to tape off the carb or intake. A vacuum leak will throw everything off. Did you have a Petronix installed or are you still using points? If the dwell is off, your timing will be affected.
Now you'll be getting into carb adjustments--idle and mixture... FUN, FUN FUN--to get everything dialed in--timing, dwell, idle rpm and mixture.
What's the condition of the carb? Was it recently rebuilt?
No dwell meter,or tach. :-[
Pertronix is installed with appropriate coil.
Unknown when carb was rebuilt. I would like to say not many miles on car since older Gent redid it all, according to his Son. Hehe. He's been right for the most part, but truly when is unk.
Mike
If it is located there , then you should hear the vacuum noise when removed. Car also would run rougher when removed.
Your going to have to do all of the things Walter and I have been telling you, to get it correct.
Points,or what ever, timing, carb settings, and etc all have to be right on.
Manuals are the best place to learn, along with advice from here.
Roy
Thanks. No noise, but can feel the suction on the line going to carb. No noticeable difference in running. Set timing to A mark.
You'll need to borrow or buy a dwell-tach and a vacuum gauge to really get things set up right. I've had mine for at least 20 years and it's paid for itself over and over.
Your next best hope is a good OLD mechanic who isn't too arthritic to bend over the fenders!
New tools and old mechanic's.
What a pair.
Roy
Jeez, must've gone to 5 places looking for tach meter. Picked up vac gauge and tach meter. More stuff to add to the garage. Wish I had a larger one.
From what I looked up there is a C and an A on the timing marks.
A= for premium fuel.
C= for regular fuel.
That's what I read in the shop manual. Tomorrow afternoon ill get back with her. Have test equipment. Will check rpm's first, and adjust if necessary. Then recheck timing is still on A mark.
Then check vac advance with gauge. Any particular readings I should be looking for?
Also paint on middle ports of intake manifold on each side of carb are completely burned off.
I did locate and free up the heat riser valve. The larger outside piece of it was in the down position. Anyone know if that's closed or open position of valve?
Thanks, Mike
Most of the time if the weight is down, the valve is closed.
Remember the distributor has to be set up first., before you set the timing.
I'm not familiar with the one you were talking about. I thought it was electronic ignition type, that didnt need adjusting.
I'm not sure what Walter wanted to do with the vacuum gage. They are nice for setting up the air/fuel mixtures on the carb. Unless your talking about a vacuum pump.
As far as the vacuum goes with the timing, you just want to see if it advances once it is put back on. But, you said the was no change, so the vacuum advance must be shot.
Paint probably burned off the intake , because heat riser was shut.
A lot of things here pointing to the over heating problem.
Yes Roy, I was thinking the same thing on my running hot problems.
Would the vac gauge determine if vac advance is working properly?
So I'm going to make sure carb is idling at correct rpm about 400rpm, in drive?
As far as I'm aware, there is no adjustment on the pertronix electronic ignition system. All preset. So there should be nothing to do with distributor. Other then disconnect vac advance, and plug line going to carb.
Then set timing to A line.
Thanks for all the help, Mike
Anyone know an old arthritic mechanic to work on a 52 in Hilton Head, Savannah area? I need my flywheel, and universals replaced. my garage space is limited on what I can attempt. Man my to do list is full of stuff to accomplish. Glad I'm down to one car.
I vacuum pump, would be for checking the vacuum advance unit. You would pump it down in a vacuum and see if it holds.
Timing light will tell you if its working, because it would advance your timing.Again if your using premium gas it is the A mark. C mark for regular gas.
Vacuum gage can be used to set up the carb , along with the tach. I idle mine down and turn mixture screws in and out to get the highest reading on the tach, and vacuum gage.
Make sure that heat riser opens once its hot.
It is never ending, but fun to work on old cars.
I have a list of about 14 things to do on mine. Waiting for the snow to melt so I can bring it up to the house and work on it again. I have another garage down back where it is kept. When it snows it is stuck there until it melts. All snow should be gone by this weekend.
The vacuum gauge--When I check my '57, I plug the gauge into the manifold vacuum line to the vacuum wipers. This is a pure manifold vacuum source. You can't or shouldn't hook it to any port on the carb. Using this vacuum source, it takes potentially leaky wiper motors out of the equation.
With the vacuum gauge attached, you want to adjust each mixture screw for highest reading and smoothest needle--not bouncing around AND the idle air screw (you should have a Rochester carb, correct?) should be at the minimum to get your idle rpm. The more you open up the air screw, the more you have to open the mixture screws to compensate for the additional air. There should be initial screw settings in your shop manual. If fiddling doesn't seem to be getting you anything but frustrated, shut off the car, gently turn the screws where they are just seated (DO NOT OVERTIGHTEN!) and then back them out to the initial settings in the manual--maybe 2 full turns on the air screw and 1.5 on the mixture screws. Let yourself and the car cool off and try it again. Eventually you'll find that spot where it sounds happy, the exhaust doesn't knock you out and it's not blowing black smoke.
As for the timing--today's gas isn't what it was 60 years ago so you may have to go back toward the "C" mark or your engine may ping. Once you think it's all set, take the car for a drive and take your tools with you (and cell phone and AAA card). You might find you have to tweak it just a little more after driving it.
Once you master this, you'll feel a lot better about your car and yourself!
Roger that Roy.
If I wire the heat riser open, would that be suitable? It doesn't seem to want to open after car is warmed up. The weight stays in closed position unless I manual open it. She is still overheating at idle, gauge pegs out. Could this possibly be the bad vac advance? Combined with heat riser. Still looking at few other things as well, But?
Will local parts store carry a vac advance for our cars?
Thanks Walter, yes it's a Roch. Carb. I haven't messed with the mixture screws yet.
I've only adjusted Rpm and timing. I need to settle this heat problem, now that's what I need cooling off from. Hehe. The timing was way advanced. Now on A. I do use premium gas. What was octane ratings back in the day? Manual doesnt say what is recommended. I go with highest for this ol Gal.
But if not high enough should I retard slightly back toward the C?
The heat riser issue has to be straightened out first. That redirects hot exhaust back to the intake to help warm up the choke so, with it closed, the car isn't breathing right. Wire it open for now. Chances are the spring or something rotted away.
Octane was rated differently back in the day. Premium then isn't what it is now, plus there was no ethanol. When you bought gas, you got GAS! Best thing right now is keep it on "A" and check for pinging under load or sluggishness. You can always retard it back to "C".
Gotcha,
Thanks, Mike
Mike the purpose of the vacuum advance is to retard spark under load.
While at idle, and cruising, the advance advances the timing. The engine runs cooler too, while advanced. It retards under load to prevent pinging, and burn the gas more completely.
Rich mixture burns faster under load, so you need to retard spark. During idle,and cruise , your mixture is leaner, and burns slower. Hence you advance spark.
If your running around with one that doesn't work, it will cause it to run hotter.
Like Walter said. Get the riser to stay open. Big cause of extra heat in engine.
Yes sireee. I Wired up heat riser as best I could. Took for short spin, and temp gauge pegged? What the hell. Ok beck to driveway, and I noticed with car shut off and key on with foot on and off brake would affect the temp gauge. I had just removed radio waiting for replacement. Hmmm ground wire from batt disconnected, so I ran to firewall. Bingo accurate gauge to work with.
Thru all that I had also taken out thermostat, and thought spring is supposed to be down not up. Tested thermo to be good. Reversed it. Set rpm to 425. And with vac line plugged I set timing to A line. Took, for spin and no problems thus far. Timing still no change when vac line unplugged. Parked in driveway idled for 5 min, and temp did go up just past middle mark. Of course the temp was only about 58 out. Add 40 degrees, and that's the real deal. Man O Man several problems all rolled into one.
Now for the advance, Napa had to call me back to tell me a no go. Any local stores have em? Who online will carry?
I'll soon attempt the carb adjustments, after I complete more critical items on my long list of stuff to do.
We plan on driving her to GN in Boston this year for a great time.
Thanks again, Mike
I am curious.
If you take an older car, say 1941-1958 as an example, that is running at an acceptable temperature AND retard or advance the spark, HOW much difference will you really see?
Anyone try this?
There is so much to consider with temperature of the car, such as outside temp, highway or city driving, going up a hill or down and on and on.
The spring on the thermostat goes down inside the water pump so the coolant passes over the spring allowing it to open. What temperature is the thermostat--165 or 180?
Walter It opened at 160.
Where would I purchase a vac advance for my car? Or can mine be repaired?
Thanks, Mike
Richard that would be interesting to know. For instance if running hot, would it be beneficial to adv or retard spark to make run cooler until problem is sorted out. Dunno.
I think Terrill Machine Shop in Texas can rebuild them. No email or website come up on a search. They usually advertise in OCW or Hemmings. A replacement will be 60 years old and the diaphragm will probably be dry rotted. You CAN rebuild them. There was a thread on how to do it: http://forums.cadillaclasalleclub.org/index.php?topic=119660.msg205204#msg205204
Generally, the differences in vacuum advances is the spring. I did this rebuild on my '57 and it does work.
Good God.
You were running the car with the thermostat upside down ?
That will make it run hotter for sure. That's one problem out of the way.
Richard. Retarding the spark and running around like that just makes the car run warmer.
Advancing it to far can cause pinging. You don't want that either.
Best to set them up the way they are suppose to be, and run them that way.
Roy
Per Hemmings:
Terrill Machine Inc.
1000 CR 454
DeLeon, TX 76444
PH: 254-893-2610
BTW, I'm curious. You didn't mention anything about vapor lock problems. One would think that if it's running that hot, you would be breaking down.
My '52 seems to run cool as a cucumber. Never more than about 1/3 off Cold, even on the hotest days. But the car vapor locks even in sub-freezing temperatures. I have solved it with an electric fuel pump.
Walter, I'm going to get the vac adv off this week to be rebuilt. A fella offered me a used, but tested one for $56. I've declined.
Roy, yep thermostat was upside down, it appeared to be stuck shut and the heat riser closed. Drove her this weekend several times into town. Hard to start at first, but seems to be running just ok, better at higher speeds. The carb def needs fine tuning. However, still running hotter then she should. It's ok when driving but stopped at light for five min and gauge will go to 3/4 mark. Installed new sender last year it should be good. So basically I've the vac advance left, and to check passages in the block, as Walter mentioned earlier.
Jim, I would on occasion have a studder, like she was missing. Vapor lock wasn't an obvious issue for the car. I did recently install a phenolic spacer. I've had an elec fuel pump since I received the car. So that may be why. Thanks for the info.
Check the pressure of the electric fuel pump, too. It may be putting out too much pressure, forcing fuel past the needles and seats in the carb...
Good luck. Keep us posted on your progress.