72 Cutlass Died
October 16th, 2011, 09:45 AM
#1
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Location: Calgary, AB Canada
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72 Cutlass Died
In the past little while my car has been doing some funny things. In regular driving the engine seems like it's misfiring, on the tach it will do a large spike and then come down it does it the worst at low speeds but still occurs at high speeds. I've been wanting to do a tune up for a while and I think It may be an ignition problem, the car hasn't been tuned up for at least a year. The other day when driving to school it did it's usual stumble but this time it got so bad it died as I was going 40 MPH, but I was able to get her started and drive home. I hope I described the issue well enough.
One person I talked to suggested that it may be the fuel pump, but I really am not sure. I'm going to probably start with a tune up and see if that works.
What does this issue sound like?
Thanks,
Dan
One person I talked to suggested that it may be the fuel pump, but I really am not sure. I'm going to probably start with a tune up and see if that works.
What does this issue sound like?
Thanks,
Dan
Last edited by Dant; October 16th, 2011 at 09:47 AM.
October 16th, 2011, 11:09 AM
#6
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I'd put a dwell meter and a timing light on it first - takes less than 5 minutes and will clear most of your ignition system, especially if your dwell meter has a "points" setting to check resistance.
If all that checks out, you need to confirm that the high voltage side is good:
Rotor, cap, wires, coil, plugs.
And then there's the fuel side, including fuel filter.
Doesn't sound like a fuel pump, but it's not out of the question.
Next time it stops, you want to jump right out and check whether the accel. pump squirts, and then check the spark.
You also need to use your head diagnostically while you drive:
Does anything seem to make the problem better or worse?
Acceleration, deceleration, left turns, right turns, hot engine, cold engine, high revs, low revs, lots of throttle, little throttle, braking (vacuum to the booster), idling, if it's rough, can you save it by pumping the pedal?
You get the idea.
- Eric
If all that checks out, you need to confirm that the high voltage side is good:
Rotor, cap, wires, coil, plugs.
And then there's the fuel side, including fuel filter.
Doesn't sound like a fuel pump, but it's not out of the question.
Next time it stops, you want to jump right out and check whether the accel. pump squirts, and then check the spark.
You also need to use your head diagnostically while you drive:
Does anything seem to make the problem better or worse?
Acceleration, deceleration, left turns, right turns, hot engine, cold engine, high revs, low revs, lots of throttle, little throttle, braking (vacuum to the booster), idling, if it's rough, can you save it by pumping the pedal?
You get the idea.
- Eric
October 16th, 2011, 11:16 AM
#7
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Location: Poteau, Ok
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Make sure your points are serviceable, look inside the cap and make sure there is not a huge amount of carbon buildup on the electodes, and inspect the rotor. Pull the sparkplugs and see what kind of shape they are in and regap to .035! I would freshen the tune!! Make sure your dwell is @ 30, and your timing is somewhere around 12-14 deg Btdc! Then readjust your idle speed to around 650 - 750 rpm. And set you air fuel mixture screws for the highest rpm or vacuum how ever you prefer.
Like they explained above a new fuel filter is probably a good idea!
Good luck!
Like they explained above a new fuel filter is probably a good idea!
Good luck!
October 16th, 2011, 03:44 PM
#8
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Location: Milwaukee, Wisconsin
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October 17th, 2011, 02:23 PM
#10
Sounds ign related to me too.
Check the simple things first:
At night, start the car with the hood open and look for arcing. You can see it better at night.
Check the points for carbon build-up like somebody else mentioned
Check if the ign wires are "clicked" into place on the cap and each plug
Check to see if the wires on the coil have a good connection, loose, or corroded.
Fixes that reqiure money:
Check the ign wires, see if they are damged, cracked, or bare in any spots. If so, replace
Pull the plugs, if they don't look right, or are the wrong plug, replace (for a 72 Olds 350 they are less than $3 a plug). (good luck with number 8)
I doubt it's fuel related, but a fuel filter is like $3 and easy to replace, so feel free to go that route.
Check the simple things first:
At night, start the car with the hood open and look for arcing. You can see it better at night.
Check the points for carbon build-up like somebody else mentioned
Check if the ign wires are "clicked" into place on the cap and each plug
Check to see if the wires on the coil have a good connection, loose, or corroded.
Fixes that reqiure money:
Check the ign wires, see if they are damged, cracked, or bare in any spots. If so, replace
Pull the plugs, if they don't look right, or are the wrong plug, replace (for a 72 Olds 350 they are less than $3 a plug). (good luck with number 8)
I doubt it's fuel related, but a fuel filter is like $3 and easy to replace, so feel free to go that route.
October 17th, 2011, 06:31 PM
#11
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Location: Milwaukee, WI
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Cutlass Died
The problem is almost certainly ignition related, but not in the way you might think...
What does the tach needle do with the key on, and the engine not running? The needle should just sit there not moving. If the needle jumps around AT ALL, the tach itself is highly suspect.
Does the problem continue with ALL leads to the tach disconnected?
If the tach has internal electrical issues, it will adversely affect the components of a points ignition-up to the point that the engine can't run at all.
Oh, and BTW, been there, and had to figure that out!
What does the tach needle do with the key on, and the engine not running? The needle should just sit there not moving. If the needle jumps around AT ALL, the tach itself is highly suspect.
Does the problem continue with ALL leads to the tach disconnected?
If the tach has internal electrical issues, it will adversely affect the components of a points ignition-up to the point that the engine can't run at all.
Oh, and BTW, been there, and had to figure that out!
October 17th, 2011, 06:40 PM
#12
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Absolutely true.
I had a bad tach once that would kill the engine at random (on a '68 Galaxie 390).
Disconnected it - no more problems.
I'd still double check your ignition system as well.
A normal tach will jump once, from zero to about 100 or 200 RPM, when you first turn on the switch - it's small enough that you might not notice it.
- Eric
I had a bad tach once that would kill the engine at random (on a '68 Galaxie 390).
Disconnected it - no more problems.
I'd still double check your ignition system as well.
A normal tach will jump once, from zero to about 100 or 200 RPM, when you first turn on the switch - it's small enough that you might not notice it.
- Eric
October 18th, 2011, 08:24 PM
#13
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The problem is almost certainly ignition related, but not in the way you might think...
What does the tach needle do with the key on, and the engine not running? The needle should just sit there not moving. If the needle jumps around AT ALL, the tach itself is highly suspect.
Does the problem continue with ALL leads to the tach disconnected?
If the tach has internal electrical issues, it will adversely affect the components of a points ignition-up to the point that the engine can't run at all.
Oh, and BTW, been there, and had to figure that out!
What does the tach needle do with the key on, and the engine not running? The needle should just sit there not moving. If the needle jumps around AT ALL, the tach itself is highly suspect.
Does the problem continue with ALL leads to the tach disconnected?
If the tach has internal electrical issues, it will adversely affect the components of a points ignition-up to the point that the engine can't run at all.
Oh, and BTW, been there, and had to figure that out!
Dan
October 18th, 2011, 08:32 PM
#14
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Location: The Hudson Valley
Posts: 21,183
Standard is one of the good old aftermarket players from way back.
Their stuff is generally considered to be of good quality, but they do usually have three quality levels, with an economy, a "regular," and a "high performance" line.
The high performance line is called Blue Streak.
A buddy of mine was their "New Parts Coordinator" back in the eighties, when most of their stuff was still Made in USA.
- Eric
Their stuff is generally considered to be of good quality, but they do usually have three quality levels, with an economy, a "regular," and a "high performance" line.
The high performance line is called Blue Streak.
A buddy of mine was their "New Parts Coordinator" back in the eighties, when most of their stuff was still Made in USA.
- Eric
November 3rd, 2011, 05:55 PM
#15
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Hey everybody just wanted to update and ask more questions. I replaced the plugs, wires, cap, and rotor. It made a huge difference in power and throttle response and barely if not any of those big tach spikes I was getting before. The carbon build up in the cap was horrendous. I figure that was stopping the spark. The compression test results were satisfactory if not worse. What was factory compression in PSI? the lowest compression was 95 and the highest was 122, so still within the 70% of highest range as stated in my emissions booklet. The plugs looked ok in general, Except for plug one and two pictured below. Can anybody tell me what this means? here is pictures of the cap, rotor, and #1/#2 plugs.
PA290625.jpg
PA290628.jpg
PA290631.jpg
Ok, I pulled the distributor the other day, and I realized I bought the wrong points! Doh! But also looking at the distributor I noticed that there isnt any shims between the gear and the housing. Is this different on Olds engines? or did somone just forget to put them in?
I also noticed that there is not the little peice that goes between the shims and the housing that has those little teeth on it, I dont know how else to describe it. ive got some shims and that little teethy guy if I need to put them in. also What would the clearence be between the shims and the gear? My teacher seems to remember it being 20 thousandths. Also my teacher told me that I should change the bushings on the advance weights, he also said that if I change one of the springs to a lighter weight spring Ill have more "get up and go" has anyone ever done this?
Thanks,
Dan
PA290625.jpg
PA290628.jpg
PA290631.jpg
Ok, I pulled the distributor the other day, and I realized I bought the wrong points! Doh! But also looking at the distributor I noticed that there isnt any shims between the gear and the housing. Is this different on Olds engines? or did somone just forget to put them in?
I also noticed that there is not the little peice that goes between the shims and the housing that has those little teeth on it, I dont know how else to describe it. ive got some shims and that little teethy guy if I need to put them in. also What would the clearence be between the shims and the gear? My teacher seems to remember it being 20 thousandths. Also my teacher told me that I should change the bushings on the advance weights, he also said that if I change one of the springs to a lighter weight spring Ill have more "get up and go" has anyone ever done this?Thanks,
Dan
Last edited by Dant; November 3rd, 2011 at 07:43 PM.
November 3rd, 2011, 09:18 PM
#16
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Location: Shorewood, Il.
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Don't know where you'd find those shims, but .020 to .030 sounds right.
Don't remember that 'toothy thing' on Olds, but once you've got it apart, clean the shaft well, and check the bushings, too.
Lighter advance springs will bring in the timing sooner - get a kit and follow the instructions, unless you've access to a distributor machine.
Also make sure your vacuum advance is functional - makes a BIG difference!
Don't remember that 'toothy thing' on Olds, but once you've got it apart, clean the shaft well, and check the bushings, too.
Lighter advance springs will bring in the timing sooner - get a kit and follow the instructions, unless you've access to a distributor machine.
Also make sure your vacuum advance is functional - makes a BIG difference!
Last edited by Rickman48; November 3rd, 2011 at 09:21 PM.
November 4th, 2011, 11:46 PM
#17
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Don't know where you'd find those shims, but .020 to .030 sounds right.
Don't remember that 'toothy thing' on Olds, but once you've got it apart, clean the shaft well, and check the bushings, too.
Lighter advance springs will bring in the timing sooner - get a kit and follow the instructions, unless you've access to a distributor machine.
Also make sure your vacuum advance is functional - makes a BIG difference!
Don't remember that 'toothy thing' on Olds, but once you've got it apart, clean the shaft well, and check the bushings, too.
Lighter advance springs will bring in the timing sooner - get a kit and follow the instructions, unless you've access to a distributor machine.
Also make sure your vacuum advance is functional - makes a BIG difference!
November 5th, 2011, 03:11 AM
#18
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Join Date: May 2011
Posts: 135
Do NOT put shims on the distributor shaft between the gear and housing. Olds engines turn distributor COUNTER-clockwise, thus causing the gear to be pulled toward the bottom, not push up to the top(thus the thrust washers), like a Chebby. If you shim it, the gear can bottom out against the block and throw the cam gear/dist gear out of alignment. With the dist installed, and hold down tightened, you SHOULD be able to pull up on the rotor/dist shaft and get SOME upward movement.(this shows it's not bottomed out)
I don't know of anyone that sells distributor bushings, but if it needs them, probably need to just replace the whole unit, as getting them aligned and then reaming them to size is difficult.
Hope this helps.
Greg
I don't know of anyone that sells distributor bushings, but if it needs them, probably need to just replace the whole unit, as getting them aligned and then reaming them to size is difficult.
Hope this helps.
Greg
Last edited by gregvm; November 5th, 2011 at 03:15 AM. Reason: more info
November 7th, 2011, 05:13 PM
#20
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I found a dwell meter today and it works! This thing must be from the 50's or early 60's. Surprise surprise 50 year old technology made in the USA still works while 25 yearold technology made in Mexico doesn't. I set the dwell to 30. Is the rpm supposed to be pretty high? It's at 1500 with a dwell of 30. I have not set the timing yet.
Can someone give me a step by step precedure to time my engine? I've never done it before.
Thanks,
Dan
Can someone give me a step by step precedure to time my engine? I've never done it before.
Thanks,
Dan
November 7th, 2011, 05:40 PM
#21
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Location: The Hudson Valley
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Dan,
You set the dwell FIRST, before anything else, THEN you set the timing, and THEN the idle mixture and speed.
If your idle speed went up, that means your timing advanced, and that means the next thing to do is timing, and then see where your idle is after that.
Not surprised that a dwell meter from the fifties still works. That's why I tell everyone to just get one at a yard sale or flea market - they always work
.
- Eric
You set the dwell FIRST, before anything else, THEN you set the timing, and THEN the idle mixture and speed.
If your idle speed went up, that means your timing advanced, and that means the next thing to do is timing, and then see where your idle is after that.
Not surprised that a dwell meter from the fifties still works. That's why I tell everyone to just get one at a yard sale or flea market - they always work
.- Eric
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