Engine trouble

Jean-Marc Dugas

PCS Member
I have been driving my 67 for 2years now with no engine trouble. This year, I had a tune-up done when I took the car out of storage, changed the plugs and wires, replaced a number of cracked hoses, etc.

I mostly drove the car in town, except for a trip to Halifax which is 3 1/2 hour eah way last week.

Everything was working well until yesterday.....

Last evening, after leaving the weekly Wedensday night cruse to the mall, the car stalled at a red light. Since then, it can not idle without staling, and when driving at highway speed, I can feel that the engine runs rough.

Any ideas on what the problem could be?
 
it's a ponco, you may have junped timming. these old gals were prone for jumping the teeth on the valve timing gear. but before you panick check the vacuum lines and I'll bet one fell off.
 
I'm with Ed on this one. It has jumped time... This means that the gear that turns the camshaft is out of synchronization with the gear that moves with the crankshaft. Be thankful that it happened at a traffic light, because if it had happened at highway speeds, you would be looking for a new engine block now. Take a look at my engine in this thread... The timing chain and gears are behind the stamped metal cover in the front of the engine. This is what you will need to get to to change the gears and chain. It isn't difficult work, but it is a messy job on an engine that is high mileage and quite dirty. I suggest that you do this job yourself, and Ed and I are here to help you along. Just do the engine cleaning like I did first, so once you are done with the repair, you can also detail your engine. You will need basic mechanics tools, with the exception of the crankshaft pulley puller. Many auto parts stores will loan this tool when you purchase the parts. I would estimate it will take you about 4 hours to get everything off the engine, since it will all be new to you. I used to do a complete timing chain job in 4 to 5 hours from start to finish, and that was without hurrying. It is easy if you follow the factory service manual. Biggest time waster is the cleaning of the parts that you take off.
If you want to make sure that it is the timing chain, you can remove #1 spark plug and manually turn the engine till #1 is at top dead center. Look at the timing mark, and it should be exactly at the "0" mark, or top dead center. If it isn't, then the timing chain has jumped a tooth. If you continue to run the engine, you run the risk of doing further damage, as the chain will jump again. I have seen where the next jump will cause a bent connecting rod, or bent push rods.
 
simple check and look for the obvious problem. it has always been my understand if all of a sudden you have trouble go to the last thing done on the car and see what fell off. understand the worse case senero but do the basics first. timming chain and gears were a 70,000 mile thing with the pontiacs. if it did jump time it most likly happend when it stalled. not that it caused the stall.
 
I'm almost at 70,000 miles, so it would fit the bill. I did check all the hoses, tubes, wires, etc.

I did not check to see if a float would be stuck in the carburator, as i do not know how to do that. Would it be safe to get some carburator cleaner spray and give it a shot?

I will have a look at the timing as Paul suggested once i get home tonight. I did order the rplacement parts for the chain, sprokets and gaskets, they should arrive on Tuesday. Might as well have this done regardless if it needs it or not. I do not want to break down on the way to (or back from) Albany.
 
Best of luck Jean-Marc, I had my timing chain and gear changed this year. It didn't jump time but the mechanic was changing the front cover seal and gasket, so why not change it.
 
timming jumped??

while your at it I would recommend going ahead and changing the waterpump also. Your already there and its easier to slap a new one on and not have that extra worry further down the road.
 
I'm almost at 70,000 miles, so it would fit the bill. I did check all the hoses, tubes, wires, etc.

I did not check to see if a float would be stuck in the carburetor, as i do not know how to do that. Would it be safe to get some carburetor cleaner spray and give it a shot?

I will have a look at the timing as Paul suggested once i get home tonight. I did order the replacement parts for the chain, sprockets and gaskets, they should arrive on Tuesday. Might as well have this done regardless if it needs it or not. I do not want to break down on the way to (or back from) Albany.

To check for a sticking float, you just need to tap the side of the carburetor gently with a screwdriver handle. If it is stuck, that should break it loose. I seriously doubt that it is anything other than a jumped timing chain. The symptoms are classic for this problem...
Don't forget to change all the belts and hoses while you have everything apart. I would also send the radiator out for a cleaning while it is out. New thermostat is also in order. I would not suggest replacing the water pump with a made in China pump, but rather send it out and have it rebuilt. It is more expensive than buying a replacement, but the replacements are not that good. Also, on the back side of the water pump, is a metal baffle plate. Make sure to reinstall this part, or the water pump will not work properly. Like I said earlier, it is also a good time to paint the engine.
 
When the engine in the 73 shot craps only days after buying the thing back in 2001 I went through a complete top side engine rebuild on that car due to it jumping time. I even had bent valves too! When we did the rebuild we replaced everything as mentioned here and cleaned up and repainted the engine as well. Now I have a pretty decent car to show with.
 
Following everyone's advice, since we have to take everything apart, I also ordered a water pump and gas pump.

All of the goodies should arrive Tuesday and I hope to have the car in the shop on Tuesday or Wedensday to get this done ASAP. I would like to take the time to do all of the repairs myself, but as always, I do not have time, and unlike Paul, the wife does not think that I should attempt these repairs myself....

The car has to be ready for the big car show (www.atlanticnationals.com) which starts on Thursday and go all the way through until Sunday. If anyone wants to come over for a drive, let me know we have a couple of spare rooms at home.

I am already missing another show this weekend in Miramichi because of this....bummer...
 
I know the feeling. We had the pleasure of experiancing a mechanical failiure a few years back on the way to my sister's in New York.

Breaking down with the Honda on an exit ramp with no street lamps in a small town at 12:30 in the morning is not a good feeling, especially for the few second after a vehicle stops behind you and 2 guys are coming out to see us....

All went well, they gave us a boost and we were able to make it to a hotel nearby. I called the local ambulance service in the morning and they were able to squeez us in their fleet centre and fix the car for us.

Being part of the EMS family has its advantages....
 
Sunday's Update

Today I went to Canadian Tire and purchased a Timing Light.

Got home, read the instructions that came with the light, read the instructions in the shop manual, checked-out a few YouTube how-to videos and off to the garage I went.

I turned the key and the car started on the first try, no problem. Opened the hood, unplugged one of the vacuum hose as indicated, hooked-up the timing light and voila. Seems that the timing is between 1/4 to 1/2 inch off the line.

No problem, I'll just turn the distributor cap and everything will be fine. Read the instructions again, and the cap does not turn; there is a notch on the base that prevents it from moving. Read the instructions again. Call on Mr. Google, until I finally tried to move the whole assembly, and voila. Almost stalled the car, but was able to un-turn it just on time.:bonk:

Put everything back together, went for a drive around the block, everything is working well. Came back home to install the beacon on the roof (I have to take it off so that the car fits in the garage) and off I go for a spin in town.

Stops at the first red light, and the car can barely keep running.:gun1: Take the side streets to get back home, keeping the engine revving at the stop signs. By the time I get home, it's running like a kitten again.

Drove up & down the driveway for a few minutes (10 feet up & 10 feet back), everything seems fine. We hit the road again and here I am back home 1 1/2 hour later.

The only problem right now is that when I stop and get going again, the engine hesitates for a fraction of a second, but otherwise, no problem.

I'll go get some carburetor cleaning stuff tomorrow and spray it in to see what will happen. Still taking the car to the shop on Tuesday to see what they'll say.
 
I am surprised no one asked if it has points or and electronic ignition conversion. Points would be the next thing I would check after the timing.
 
I am surprised no one asked if it has points or and electronic ignition conversion. Points would be the next thing I would check after the timing.

It currently runs on points. I have an electronic ignition conversion in the dashboard that will hopefully be installed this week.
 
I am surprised no one asked if it has points or and electronic ignition conversion. Points would be the next thing I would check after the timing.

The point gap / dwell angle on that engine isn't going to be off that much that it will effect the timing dramatically. I am still betting on it having jumped the timing chain one tooth. The fact that previously it was running fine and suddenly it isn't, and the timing is off the mark is a good indication to me. The only way he will know for certain is if he removes the spark plugs and turns the engine over by hand and finds the top dead center of the number one cylinder by inserting a straw into the spark plug hole. Then check the timing mark, and it should be exactly on the "9" mark. If it isn't, then it has jumped a tooth. The strange thing about timing chains is that they can either jump forward or backward. The fact that it is running better, doesn't mean that the problem is resolved. It means that you now have the spark occurring at the correct time that the piston is coming to the top of the cylinder. The valves are still out of time with the rest of the engine. If you don't fix it properly now, in a couple of weeks you will be looking for a new engine block. I have seen where the timing chain jumps a few teeth, and it will do a lot of damage, such as bent push rods, bent connecting rods, or even throw a rod through the side of the block.
 
Like Paul said, we're all betting it jumped time. Even though you've moved the distributor to reset the timing, the camshaft isn't synchronized with the crankshaft anymore so instead of cylinders firing at top of stroke, it's either prematrue detonation now or just after top of stroke. This would explain the hesitation you now have. Tear it down in the front man & see, but before you tear it apart set the crank on top-of-stroke for #1 cylinder... when the timing chain cover is removed you'll plainly see if the timing marks are off. Typically on the older GM gears they have an indentation on the cam & crank gears... looks like a drill bit started drilling a hole... they should face eachother exactly. And like Bruce said, install steel gears & not a fiber-toothed cam gear. The old chain will probably have alot of play as well. We're just looking out for you Jean-Marc... good luck & keep us posted.
 
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