Attempt to Eliminate PreIgnition

slow down guys this guy has 18 posts and says he doesnt know for sure how to set timing. all these ideas ^^ hes gonna be out there with a plunger and a jockstrap tryin to fix it.

baby steps.

try not to die -

- saylor
hahaha
As much as I don't want to admit it, I don't know much about the inner workings of engines, just a surface level of knowledge.
 
Seriously, one step at a time, and easiest first. Pull and read some plugs. Then google how to read plugs to know what you're looking at. That can tell you if your heat range is too hot or just right, and a lot more. Then I would verify the timing as other have said. If the problem still exist, then start backing off timing and/or changing heat ranges and go from there.
 
The stock rear gear in a '67 Fury was a 2.96 (2.9 something) and it is a great gear IMHO for a driver.

In my experience with late '60's MOPARS whose engines remain untouched internally is that they tend to have carbon build up and that they prefer premium fuel or turning the timing back a little bit, which hurts performance. There is a GM product that I can't recall the name of that is supposed to be great at removing carbon deposits. Personally, I run all my C Bodys on premium fuel to avoid pre-ignition and maintain the performance level that I desire. Also, IMHO, if the heads have not been redone with hardened valve seats some lead additive should be added now and then to keep the valve seats from wearing.

The lead in gas back in the day acted the same as increasing the octane. You could try some lead additive with premium gas to see how the car runs. If it stops or reducing pre-ignition, then you can head down the path of tune up related and timing adjustment tasks.

Engine temperature can create pre-ignition if the engine is running too hot. Don't rely on the factory temp gauge to be accurate and keep in mind it does not have temperature markings. A new thermostat might help if the engine is running too hot. Check the engine temperature with a laser temperature measuring device or a thermometer making sure the thermostat is opening when it should.

If the engine has not been converted to electronic ignition, doing so can help your problem and drivability.

While the engine has low miles, its 50 years old and the timing chains can stretch over time. If the timing chain is the original I would put replacing it toward the top of your to do list. A stretched timing chain can result in pre-ignition.

As suggested by others, take one step at a time and if you don't have one, buy a Chilton's manual or a similar manual to help walk you through how to do and test things.

Good luck.

Bill
 
Thanks guys, getting rid of some carbon build up did seem to help a lot, but I haven't driven her under load when at full operating temp yet.

The stock rear gear in a '67 Fury was a 2.96 (2.9 something) and it is a great gear IMHO for a driver.

In my experience with late '60's MOPARS whose engines remain untouched internally is that they tend to have carbon build up and that they prefer premium fuel or turning the timing back a little bit, which hurts performance. There is a GM product that I can't recall the name of that is supposed to be great at removing carbon deposits. Personally, I run all my C Bodys on premium fuel to avoid pre-ignition and maintain the performance level that I desire. Also, IMHO, if the heads have not been redone with hardened valve seats some lead additive should be added now and then to keep the valve seats from wearing.

The lead in gas back in the day acted the same as increasing the octane. You could try some lead additive with premium gas to see how the car runs. If it stops or reducing pre-ignition, then you can head down the path of tune up related and timing adjustment tasks.

Engine temperature can create pre-ignition if the engine is running too hot. Don't rely on the factory temp gauge to be accurate and keep in mind it does not have temperature markings. A new thermostat might help if the engine is running too hot. Check the engine temperature with a laser temperature measuring device or a thermometer making sure the thermostat is opening when it should.

If the engine has not been converted to electronic ignition, doing so can help your problem and drivability.

While the engine has low miles, its 50 years old and the timing chains can stretch over time. If the timing chain is the original I would put replacing it toward the top of your to do list. A stretched timing chain can result in pre-ignition.

As suggested by others, take one step at a time and if you don't have one, buy a Chilton's manual or a similar manual to help walk you through how to do and test things.

Good luck.

Bill

Bill, I think you're right with the rear gear ratio, that does seem to ring a bell. I am almost certain that the 318 is bone stock, so you could be right. I think I'll try lead additive next time I fill up. The engine is always right in the middle of the gauge, which I assumed was right. I have put in a new 180* (I believe it was 180*) thermostat. After I kill the engine, if it is warm, and I let it sit for a few minutes, and turn the key back into ON, the gauge will read much higher, sometimes (rarely) near the top of operating range. I assumed that this was due to the really hot cylinder walls and heads spreading out their heat after there's no more coolant flow. Because of this I have started to let the car "cool down" by idling for a short while after high load driving (I live on the top of a pretty tall, steep hill with many curves). The car does have electronic ignition, which I'm grateful for because I would be fine to go my life without dealing with points. I can't be sure, but I am willing to bet that it's the original timing chain. Is there any tests I could do without taking off the timing cover and dealing with that can of worms? The timing chain is not going to be my next step, but I will keep it in mind. Thanks for your thoughts.
 
I will check the plugs soon, and see if there is signs of detonation. (Which can be seen as chips or damage on the plug as cracked insulator part?) The plugs are of unknown age, and look pretty old so I am replacing them anyway. I can try one step cooler once the weather permits and I have some extra time on my hands to play with.
 
Thanks guys, getting rid of some carbon build up did seem to help a lot, but I haven't driven her under load when at full operating temp yet.



Bill, I think you're right with the rear gear ratio, that does seem to ring a bell. I am almost certain that the 318 is bone stock, so you could be right. I think I'll try lead additive next time I fill up. The engine is always right in the middle of the gauge, which I assumed was right. I have put in a new 180* (I believe it was 180*) thermostat. After I kill the engine, if it is warm, and I let it sit for a few minutes, and turn the key back into ON, the gauge will read much higher, sometimes (rarely) near the top of operating range. I assumed that this was due to the really hot cylinder walls and heads spreading out their heat after there's no more coolant flow. Because of this I have started to let the car "cool down" by idling for a short while after high load driving (I live on the top of a pretty tall, steep hill with many curves). The car does have electronic ignition, which I'm grateful for because I would be fine to go my life without dealing with points. I can't be sure, but I am willing to bet that it's the original timing chain. Is there any tests I could do without taking off the timing cover and dealing with that can of worms? The timing chain is not going to be my next step, but I will keep it in mind. Thanks for your thoughts.

The simplest way to check for a loose timing chain is to get a breaker bar and socket and hook it to the big nut on the balancer. Turn the engine until you have the timing mark at TDC. Remove the distributor cap and have a helper rotate the crankshaft back and forth with the breaker bar. Do this several times and note how many degrees the crankshaft moves before the distributor rotor starts to move. It should not move more that 10-12 degrees. If it moves more than that, the chain is loose and needs to be replaced. If it moves 20 degrees, the chain is at the point of failure. Be sure the key is off when doing this test.

Dave
 
The simplest way to check for a loose timing chain is to get a breaker bar and socket and hook it to the big nut on the balancer. Turn the engine until you have the timing mark at TDC. Remove the distributor cap and have a helper rotate the crankshaft back and forth with the breaker bar. Do this several times and note how many degrees the crankshaft moves before the distributor rotor starts to move. It should not move more that 10-12 degrees. If it moves more than that, the chain is loose and needs to be replaced. If it moves 20 degrees, the chain is at the point of failure. Be sure the key is off when doing this test.

Dave

Thanks Dave, seems simple enough. I'll have to get a 1 1/4 socket but I can try that next time our Oregon weather permits and I remember to, if I haven't sorted the issue.
 
Thanks Dave, seems simple enough. I'll have to get a 1 1/4 socket but I can try that next time our Oregon weather permits and I remember to, if I haven't sorted the issue.
It's probably a good idea to take note of Dave's suggestion and actually "do" it as it'll be one less potential problem off the list. All things considered you're doing well for 16.

Keep up the good work.
 
Check to make sure the mechanical advance is free also easy check take the cap off and turn the rotor by hand it should move a bit and return to where you started might not have ever had the felt under the rotor oiled and binded up.
 
slow down guys this guy has 18 posts and says he doesnt know for sure how to set timing. all these ideas ^^ hes gonna be out there with a plunger and a jockstrap tryin to fix it.

baby steps.

try not to die -

- saylor
Now I'm interested... Do you have instructions for how to set timing with a plunger and a jockstrap? :D
 
Yeah thats true. I check dizzy and vacuum advance first. Plugs and wires are old so I am replacing them anyway though.
If the plugs are in fact old and have been in use for lots of miles... They are not the cause of this problem. A heat range issue would show up right away, and might become worse as the hotter weather comes around. Tons of good advice in this thread... IMO, playing with timing (free) is the easiest option, or carbon cleaning with water... careful to only dribble it.
 
Another source of pre-ignition could be a stuck heat riser. If it is stuck in the closed position, that super heats the intake manifold and the center of the heads causing pre-ignition problems.

Dave
 
Charles, The temperature rising after you shut off the car is normal and many refer to it as a heat sink condition. What you are doing is fine, but likely is not necessary unless it is extremely hot out.
 
I've done that........ The plunger held the hood up and jock strap should only be worn while setting the timing when no one can see you.
Whew... close one... I was just about to try this before I finished the sentence. :rofl:
 
Thanks guys, getting rid of some carbon build up did seem to help a lot, but I haven't driven her under load when at full operating temp yet.



Bill, I think you're right with the rear gear ratio, that does seem to ring a bell. I am almost certain that the 318 is bone stock, so you could be right. I think I'll try lead additive next time I fill up. The engine is always right in the middle of the gauge, which I assumed was right. I have put in a new 180* (I believe it was 180*) thermostat. After I kill the engine, if it is warm, and I let it sit for a few minutes, and turn the key back into ON, the gauge will read much higher, sometimes (rarely) near the top of operating range. I assumed that this was due to the really hot cylinder walls and heads spreading out their heat after there's no more coolant flow. Because of this I have started to let the car "cool down" by idling for a short while after high load driving (I live on the top of a pretty tall, steep hill with many curves). The car does have electronic ignition, which I'm grateful for because I would be fine to go my life without dealing with points. I can't be sure, but I am willing to bet that it's the original timing chain. Is there any tests I could do without taking off the timing cover and dealing with that can of worms? The timing chain is not going to be my next step, but I will keep it in mind. Thanks for your thoughts.

Charles: In my experience, every engine is a little different as regards timing settings. I usually ball-park the timing with a timing light at say at 10 to 12 degrees BTDC, and I leave the distributor hold-down bolt tight enough so the distributor won't move, but loose enough, so I can move it by hand. Then I drive the car, let it warm up and listen to hear if it pings. If it doesn't, I advance the timing a bit by moving the distributor and driving it and moving it again and again until it starts to ping. Then I back it off bit by bit, until it pings no more. Also, you should only run high-octane gas. Even regular gas back in the day was higher octane than the weasel piss we have today. Someday I will tell you about marine 2-cycle oil with TC-W3. . . But not today.
 
Lots of info here. Don't chase shadows. Your problem is in 3 maybe 4 things to check. Timing, temp, octane, maybe fuel/air ratio.
Fuel/air can be checked with quick plug pull or a finger in the tailpipe. Heavy black soot in plug or in pipe, too much fuel. Very clean white tips on the insulators is maybe too lean. If engine runs okay I doubt this is your issue.
Temp, if it runs normally between 180-190 this is perfect.
Octane, it is a 318 it will run on just about any 87 swill you can buy. Except if it is really carboned up. You can get some cylinder carbon cleaners from a auto parts store, just follow instructions on the can and it will not hurt FWIW.
Timing, you say it is correct but you do not know how to set it (search you tube for videos). I'm going to take a shot from the hip and say something is amiss with your marks or you are looking at it wrong. One solution is to check timing marks for accuracy, but that is involved. Go borrow, rent, or buy a vacuum guage and set the timing and idle mixture screws to the highest reading you can get again see you tube for videos. There is a 1/2" headed bolt on the passenger side of the distributor that holds the bracket down to hold dist, loosen this bolt a little so you can move dist around. Give this a try I'm going to guess someone bumped the timing advanced to get it to run better/smoother to sell to you. You will just have to correct it.
 
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