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I went to Orilleys auto parts and rented a tube and blue chemical to go in it. You hold it on the radiator in place of the cap. Run the motor and if the chemical turns yellow it's a sign of head gasket leak. It will not show which cylinder is leaking though. The leak down test is probably the best bet.
On the cooling system or cylinder compression? I suppose both might be a good idea.
A leakdown tester is somewhat like a compression tester. It screws into the spark plug hole and uses compressed air to test for leakage in the combustion chamber. If the head gasket is blown, you will both see a drop in cylinder pressure on the tester and will hear air hissing in either the cooling jacket or the oil pan, depending on where the head gasket leak is.
Another update, I put a vacuum gauge on it today, was nearly dead steady at -19 inches, so I think that should rule out stuck valves or a number of other things that could be causing my car to sputter a bit under light acceleration.
One night this week I'm going to run a compression check and also try to find someone to run a leakdown test. I also want to pull the thermostat out one evening and see if that helps with the running hot.
In the meantime, the mechanic I had the car with last week said he would replace the head gaskets for $900, so I'm starting to think about that. Since my car has the J heads, I figure I may as well upgrade while the heads are off. What do you guys think? Any recommendations on a good set of heads? I looked at Edelbrock heads, they sure seem expensive at $2000 a pair.
On the cooling system or cylinder compression? I suppose both might be a good idea.
The one I rented goes on the opening of the radiator with the motor running and the blue liquid in it changes yellow if combustion gases are in the cooling system. The gases would get in there due to a leak between the cylinders and water jackets. Joes way tells you which cylinder if any is leaking. His way sounds better.
Right, of course. That's why I said that this week I would be running a compression check and finding someone to do a leak down test on it.
To be more clear, what I meant was if/when I am able to determine that it is indeed the head gasket that needs to be replaced, what thoughts or advice would anyone offer on how much there would be to gain by replacing the J heads since they would be coming off at that time anyway? Would the performance gain be worth it?
The other question is does anyone know what options are out there aside from OEM or Edelbrock heads?
I forgot about that test you mentioned, Gary. I'll try that this week also. Thanks!
Best bang for the buck are the Chinesium ProComp heads, ported and assembled by Bernard Mondello (Joe's son, who is not affiliated in any way with the company). ProComps are E-brock knock-offs, and with proper porting these are a great choice.
If your doing the leak down test it may be unnecessary to do the blue liquid test I did unless you just want to double check. If you do find you need head gaskets I have a habit of wanting to freshen up any time I take something off my motor. I would not want to put the heads back on without redoing them or replacing with better. It falls into the MAW category. Probably why I'm always broke.
Discovered something last week, coolant is already rusty, thinking maybe that I just need to keep flushing, so I ordered some Thermocure to run through the system. I drained a little coolant out and put it in a glass jar so I could get a better look at it, here's what it looks like after sitting for a few days:
Well guys, one $80 remanufactured distributor later and my problems are solved. The advance wasn't working at all and the wire inside the distributor was fried. It starts, idles, and runs beautifully now that I have full spark and proper advance, which also solved my temperature issue and the off idle hesitation.
Well, now you can disassemble the original at your leisure, get it all just right, and then re-install it if you ever want to see which advance curve you like better.
At the very least, once you've done that, you'll have an excellent understanding of how it works.
For $80 less, you can take the one you have apart and clean it.
Glad you found the problem!
- Eric
There was a lot more to the problem than it being in need of a cleaning. The wire in the distributor was fried, the vacuum canister was rusted out so it wasn't holding a vacuum, and the vacuum mechanism itself had rusted to the point that it also was frozen. I priced out the cost of the parts I needed to rebuild it, and it was within a few dollars of a remanufactured distributor so I went that route. The cam lobe was worn down the old one as well. I work for a company that performs election polls, so we are slammed right now, and I work long hours 7 days a week and will be until the end of November, so I made the best decision for me from both a time and money standpoint.
And I did check the timing, numerous times, but only at idle because I don't have the expensive timing light with the advance feature. The timing was ONE of the problems I was having, but not the only one. The spark jumping inside the distributor was also causing the off-idle hesitation issue because that is now gone as well.
I don't know why everyone always feels the need to question buying replacement parts over rebuilds, but I can tell you that had I done so from the very start, I could have spent a heck of a lot more time behind the wheel this past summer.
Clearly, with your work schedule, messing around with the old one instead of just replacing it makes no sense, but I think you're over-thinking what it would take to get the old distributor working properly (at a time when work has eased up).
Once you've removed the old points and condenser (and it appears from your posts that you had them installed incorrectly, though there are no clear photos of this), you can drive out the roll pin that holds the gear on the shaft and pull the shaft out of the body.
On the shaft, you can remove the tiny "E" clips and the springs and take the centrifugal advance apart.
You can remove the two screws that hold the vacuum advance in, and remove it, and then remove the points plate.
That is all it takes to disassemble the distributor, and requires about five minutes, fifteen if you've got to go back and forth to the toolbox.
If the bushings are worn to the point where there's radial pay in the shaft, they can be replaced, but it's probably not worth the trouble.
If the points cam lobes are worn, as you said, then you would need a new shaft, and, again, it's probably not worth the bother, but I must say that I've never seen one that was that worn, so, though it may not look exactly the same as your other one it may be fine.
Of course, a Pertronix or similar electronic trigger system can be installed, which uses a separate hall effect sensor that you attach to the shaft, which makes the condition of the cam lobes irrelevant.
Other than that, a vacuum advance canister costs from 12 to 15 dollars, a points plate ground wire (which seems, from the picture and from your symptoms, to be what's broken) costs about 6 dollars, and you already have new points and condenser and some grease, which are all you need to put the whole thing back together and working great.
I guess I kinda don't see why this is a big deal (notwithstanding your work schedule, of course).
I think he made a wise choice in going with the rebuilt unit vs screwing with the old one. If he wants to check the timing curve compared to the old setup, all he has to do is compare the weights. I doubt it will make a huge difference.
I didn't say it was unwise. In fact, with his schedule, it was probably the wisest choice.
If it were me, though, there is no way that I'd be able to leave the old one alone until I'd taken it apart and figured out exactly why it didn't work, and I'd also have an interest in comparing both the timing curves and the performance of both units (hey, the new one may have a better curve for modern fuel - who knows?).
Just making the point that fixing that unit is not, er... rocket science.
Lol, on the poll thing! If we knew then no one would need our polls
You gave a very accurate description of the teardown, I did do all that but man, every piece was worn out and/or rusted. And yes, the time for droptops here in VA is vanishing quickly for the year so I just got the new one. I will rebuild the old one just for the heck of it , but not until work returns to normal.
Acid works, removes hard water scale, corrosion etc. I used CLR, a couple of bottles left in for a couple weeks. Added water pump lubricant to be safe, flush multiple times before the new coolant is added.
Citric acid works great to clean the cooling system. You can get a 7 once package at Walmart. It is in powder form. I put it in my 54 Olds and ran it for a couple weeks (I do not drive the car every day). The get one of those flush kits that goes in the heater hose and flush it until the water is clear. I took my thermostat our before I flushed the car. Citric acid will clean rust off parts also. You can also get it on Amazon.
Some things I learned on my street driven 69 455 hi-compression , maybe can help others.
Check all basics first , compression, exhaust gas in coolant, radiator rodded out, fan clutch good, timing, etc etc
I like 4 core copper radiator.
1. got rid of high flow thermostat, went with small orifice thermostat to slow down coolant flow to dissipate more heat(This is NOT TRUE, Corrected later in this thread,--- Why it does work is that it keeps more pressure in the heads and block, to pick up more heat). helped mine a lot. I run 195deg stock thermostat temp for stock gasoline atomization..
2. New AC Delco 15lb cap was crap and tested 5lbs, new Standt 16lb cap tested 17lbs no more spu over. Autozone has lots of tools for free rent.. check it out.. added overflow tank, radiator always full... also using Water Wetter and 50/50 coolant mix.
3. Mark haromonic balancer in increments to 50 Deg and do full rpm advance check.. see
Curve of distributor was wwwaaayyyy off. got recurved and complete rebuild of original distributor again helped some more
4. Got quadrajet rebuilt by Cliffs High Performance went from 49 primary rod to 44, way cooler now pretty much at thermostat temp 195. keep stock 70 jets and AU secondaries no more pinging, new gas with ethanol is crap... Worse in California.....
Fred
Last edited by FStanley; Dec 5, 2017 at 12:38 PM.
Reason: Correction
Reducing flow reduces temperature gradient across the radiator, which reduces cooling.
It's a law of physics. You can't make it go away. We've discussed it here several times.
Everything else you said makes sense.
- Eric
OK
then what explains the temperature drop when I got rid of high flow stat and replaced with a std one? Maybe disipation is not correct term here, but I got a definite improvement especially at freeway speed.
I have to say, I've never heard pulling out a high flow T-stat and replacing with a regular T-stat for a cooler running engine.
Something else is up with that, just like (Md) Eric mentioned.
then what explains the temperature drop when I got rid of high flow stat and replaced with a std one? Maybe disipation is not correct term here, but I got a definite improvement especially at freeway speed.
Fred
Was it a Mr Gasket brand High Flow? I had one that would flow partially around town, could feel it in top hose and close up almost completely at highway speed, it slowly got worse and worse flow till it basically completely closed!
going to std thermostat instead of high flow thermostat helped quite a bit, and yes it was a Mr. Gasket high flow.
I later did other things like curve distributor to spec and went to smaller primary rods in Quadrajet. The smaller rods made another dramatic reduction of temps especially at idle..
... went to smaller primary rods in Quadrajet.
The smaller rods made another dramatic reduction of temps especially at idle..
Sorry. Once again, not possible.
Metering rods, whether primary or secondary, have no effect on fuel flow at idle.
They do affect fuel flow at cruise, though.
Check the diagrams of fuel flow in the Chassis Service Manual or QuadraJet Manual, then take a carburetor apart and confirm flow through the various passages yourself.
Metering rods, whether primary or secondary, have no effect on fuel flow at idle.
They do affect fuel flow at cruise, though.
Check the diagrams of fuel flow in the Chassis Service Manual or QuadraJet Manual, then take a carburetor apart and confirm flow through the various passages yourself.
well it is possible if the primary throttle plates are not 100% shut at idle. I run a pretty high idle do to my lumpy cam like about 900 rpm So I'll bet the primary system is supplying some fuel at this rpm.
going to std thermostat instead of high flow thermostat helped quite a bit, and yes it was a Mr. Gasket high flow.
I later did other things like curve distributor to spec and went to smaller primary rods in Quadrajet. The smaller rods made another dramatic reduction of temps especially at idle..
I also did another experiment to see if I could get it to cool better. I took the same type of thermostat I am using now and drilled two, then 3, then 4 1/4" holes in the flat part of the thermostat to see if a little more flow would help.. Each time, it ran hotter...
Got a new same type of thermostat a 195F Deg Autozone valuecraft and it cools better. just out of the box. I have a 270 Deg sweep gauge and I can see small changes easily... Not sure why but the slower flow seems to work for me..
Some 16F Degs cooler at idle, and 8F Deg on freeway.
well it is possible if the primary throttle plates are not 100% shut at idle. I run a pretty high idle do to my lumpy cam like about 900 rpm So I'll bet the primary system is supplying some fuel at this rpm.
But in that case, your carburetor is set up wrong and needs larger idle jets and a weaker power valve spring to compensate for low vacuum at idle.
If you read Cliff Ruggles's QuadraJet book, he explains it.
And, even if this is the case, the minimal amount of fuel consumed at idle should preclude your primary jets being the limiting factor in your idle fuel supply - the jet-needle size differential would have to be extremely small to have an effect on fuel flow at idle.
Drilling holes in stock thermostats is above and beyond and a good effort to solve a problem but trying random things to solve a problem can be deceiving and waste time and money. MDMECHANIC is an excellent source of info. Post everything you've done to the motor as well as age of parts and have confidence in advice you recieve here. I'm no expert but unless you are running a one core radiator I find it hard to convince myself that a high flow thermostat would cause heating problems. Good luck with your issue.
But in that case, your carburetor is set up wrong and needs larger idle jets and a weaker power valve spring to compensate for low vacuum at idle.
If you read Cliff Ruggles's QuadraJet book, he explains it.
And, even if this is the case, the minimal amount of fuel consumed at idle should preclude your primary jets being the limiting factor in your idle fuel supply - the jet-needle size differential would have to be extremely small to have an effect on fuel flow at idle.
- Eric
Actually Cliff rebuilt it, no kidding... and yes I have the book too..
Just trying to pass on what's been working for me. One can believe or not, it's OK wit me..
Last edited by FStanley; Jan 27, 2017 at 07:52 PM.
He is good, and should have accounted for any variations from stock that you told him about.
I am curious, did you discuss the changes with him?
If so, I would be interested in his opinion, as he's done a whole lot of these and has the sort of practical experience that few of us here have, as experience tends to trump theory.
Thanks for sticking with me (us) on these questions, because every bit of real-life information has the potential to help all of us at some point.
