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TR3driver
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There are several ways of checking valve timing with only the rocker cover off. Unfortunately, none of them are particularly simple, and unless you somehow got a camshaft that is not cut properly, the timing would be the same for all cylinders. So that's probably not your best next step.
Checking compression (or leakdown) still seems like the next step, to me.
Or just ignore the problem. If I understand you correctly it's not causing any operational issues, just some soot on the plug. Unless it continues to foul (to the point it misfires) or glaze, it can be safely ignored.
Er, I don't mean to be obnoxious or anything, but do you think you would notice if it were only making 75 hp instead of 100 ? Your driving habits sound very conservative to me.
Checking compression (or leakdown) still seems like the next step, to me.
Or just ignore the problem. If I understand you correctly it's not causing any operational issues, just some soot on the plug. Unless it continues to foul (to the point it misfires) or glaze, it can be safely ignored.
Er, I don't mean to be obnoxious or anything, but do you think you would notice if it were only making 75 hp instead of 100 ? Your driving habits sound very conservative to me.
OP
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Jim,
I'm afraid that is a bit beyond my capabilities, but when I take the car in next winter for work I plan to have done on it, I'll ask the mechanics to do a thorough inspection of the valves, etc., to see if they can get down to the bottom of this mystery.
Thank you for the information and the link.
Randall. Of course, you are right. As long as the car is running well and not misfiring, I ought to forget this mystery and, as I told Jim above, wait until I can get it back into the hands of some professional mechanics. Perhaps I'll try the hotter plugs and see what happens, or perhaps I'll just continue with what I have.
I do plan to check the balance of the carbs once more and adjust the mixture -- as much out of interest in tinkering with the car as anything else. A retired master mechanic friend of mine is coming by later this week to teach me how to check the timing, use a dwell meter, do a compression check, and check for possible vacuum leaks.
Springtime has finally come to Virginia. The azaleas are nearly in bloom and the redbuds are coming out. Time to leave this office and computer and hit the road.
I'm afraid that is a bit beyond my capabilities, but when I take the car in next winter for work I plan to have done on it, I'll ask the mechanics to do a thorough inspection of the valves, etc., to see if they can get down to the bottom of this mystery.
Thank you for the information and the link.
Randall. Of course, you are right. As long as the car is running well and not misfiring, I ought to forget this mystery and, as I told Jim above, wait until I can get it back into the hands of some professional mechanics. Perhaps I'll try the hotter plugs and see what happens, or perhaps I'll just continue with what I have.
I do plan to check the balance of the carbs once more and adjust the mixture -- as much out of interest in tinkering with the car as anything else. A retired master mechanic friend of mine is coming by later this week to teach me how to check the timing, use a dwell meter, do a compression check, and check for possible vacuum leaks.
Springtime has finally come to Virginia. The azaleas are nearly in bloom and the redbuds are coming out. Time to leave this office and computer and hit the road.
HerronScott
Darth Vader
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Ed,
How about some pictures showing us the plugs?
Scott
How about some pictures showing us the plugs?
Scott
OP
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OK... will do.
OP
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Scott,
Here are two Champion spark plugs. I put the first in new and drove 175 miles, took it out, and this is what I found. I then put another new Champion and drove about 15 miles, took it out, and found the same thing. Whether they are sooty or carbon fouled, they don't look like the other three spark plugs (#s 2, 3, 4) which are textbook normal.
This is what has bothered me.
Here are two Champion spark plugs. I put the first in new and drove 175 miles, took it out, and this is what I found. I then put another new Champion and drove about 15 miles, took it out, and found the same thing. Whether they are sooty or carbon fouled, they don't look like the other three spark plugs (#s 2, 3, 4) which are textbook normal.
This is what has bothered me.
Attachments
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What Champions are you using? I can't quite see any ID on the photo.
For what it's worth I was having problems with all four plugs carbon fouling on my TR3. I switched to NGKs and the problem disappeared. Personally I don't think the Champions are as of good quality as they used to be. You could try opening the spark plug gap on that plug to .028 and see what happens.
Hap Waldrop
Yoda
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Three words:
leak down tester
leak down tester
hondo402000
Darth Vader
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anybody thought about the rings not seated yet 
Hondo
Hondo
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The Champions I have in the car came from Moss and are the ones they recommend: Champion Copper Plus, L87YC.
If I were to switch to NGKs, should I use NGKBP 6HS (cooler) or NGKBP 5HS (hotter)?
The mechanics who rebuilt my engine performed a leak-down test to determine that it had to be rebuilt. The engine was rebuilt about 11 months ago. Since then, I have put about 5000 miles on the engine. Should be enough for the rings to be seated.
If another leak-down test is recommended, it will have to be done next winter when the car is in the shop for other work (rebuild rear end, etc.).
Karls59tr: Mystery is... only #1 is "fouling." The other three are in excellent condition.
BTW. Leak-down testers are moderately priced, but they have to be attached to a compressor, which are expensive. Is there any way to get around having to use an electric compressor to get the leak-down tester to 100 psi?
If I were to switch to NGKs, should I use NGKBP 6HS (cooler) or NGKBP 5HS (hotter)?
The mechanics who rebuilt my engine performed a leak-down test to determine that it had to be rebuilt. The engine was rebuilt about 11 months ago. Since then, I have put about 5000 miles on the engine. Should be enough for the rings to be seated.
If another leak-down test is recommended, it will have to be done next winter when the car is in the shop for other work (rebuild rear end, etc.).
Karls59tr: Mystery is... only #1 is "fouling." The other three are in excellent condition.
BTW. Leak-down testers are moderately priced, but they have to be attached to a compressor, which are expensive. Is there any way to get around having to use an electric compressor to get the leak-down tester to 100 psi?
BP6HS. See today's post on plug gaps. Why not try widening the plug gap on that one cylinder and take it for a drive.I just remembered that my TR3 was running rough this Fall and I had one badly carbon fouled.....the #3 plug! I dont know how to account for this phenomena but is maddening.
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Karls59tr,
Thanks. That's an option.
But before I do, let me make certain that I understand that running one spark plug a little wider than the others (.028 rather than .025) will not damage anything.
One source on spark plugs writes: "A spark plug gap should be made as small as possible, while still maintaining performance. A wide spark plug gap can cause hard cold starting, misfires during the rich or lean fuel conditions, and reduction of upper rpm range. To maintain a good secondary spark (multiple spark) within a wider rpm range it is wise to run a narrower spark plug gap. It is better to precisely place two stable, consistent sparks than to fire one wider spark that may cause misfires under various conditions."
Thanks. That's an option.
But before I do, let me make certain that I understand that running one spark plug a little wider than the others (.028 rather than .025) will not damage anything.
One source on spark plugs writes: "A spark plug gap should be made as small as possible, while still maintaining performance. A wide spark plug gap can cause hard cold starting, misfires during the rich or lean fuel conditions, and reduction of upper rpm range. To maintain a good secondary spark (multiple spark) within a wider rpm range it is wise to run a narrower spark plug gap. It is better to precisely place two stable, consistent sparks than to fire one wider spark that may cause misfires under various conditions."
I may have given you some misinformation. maybe let some others offer there take on widening the plug gap on one plug before you try it. I do know however that if you are running a higher output Sport Coil that you have to widen the gap on the plugs.
Just thought of something in regard to valves.I have heard that the face of the rocker arm where it contacts the valve can become grooved over time so that the feeler gauge will not give an accurate reading when you are setting the valves. I assume that the rocker faces were cleaned up when you had the engine rebuilt but if that rocker on the # 1 cylinder didn't get cleaned up then the valves would not get a true adjustment and cause the problem.Just a thought!
Just thought of something in regard to valves.I have heard that the face of the rocker arm where it contacts the valve can become grooved over time so that the feeler gauge will not give an accurate reading when you are setting the valves. I assume that the rocker faces were cleaned up when you had the engine rebuilt but if that rocker on the # 1 cylinder didn't get cleaned up then the valves would not get a true adjustment and cause the problem.Just a thought!
OP
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Hi, Karls59tr,
I am just running a stock coil on the car.
As for the rocker faces, I had all the rockers replaced when I had the engine rebuilt about a year ago. so I think it should be OK. But thanks for the thought.
It remains a mystery.
I am just running a stock coil on the car.
As for the rocker faces, I had all the rockers replaced when I had the engine rebuilt about a year ago. so I think it should be OK. But thanks for the thought.
It remains a mystery.
AweMan
Jedi Knight
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F.W.I.W. just my 2 cents.
Were it mine ... I would preform a compression test, both wet and dry.
IF the compression test reads within the acceptable range I would throw in a step hotter plug in the #1 cylinder and drive it like I stole it!
If the compression test is not within the acceptable range at least you have an indication as to what the problem may be ... eg. rings or valves.
It could be as simple as the rings in the #1 cylinder havn`t completely seated yet.
or as complex as a broken ring in that cylinder. or even a valve not properly seating as you have suggested.
Rings do occasionally get broken upon instillation ... just saying ...
Were it mine ... I would preform a compression test, both wet and dry.
IF the compression test reads within the acceptable range I would throw in a step hotter plug in the #1 cylinder and drive it like I stole it!
If the compression test is not within the acceptable range at least you have an indication as to what the problem may be ... eg. rings or valves.
It could be as simple as the rings in the #1 cylinder havn`t completely seated yet.
or as complex as a broken ring in that cylinder. or even a valve not properly seating as you have suggested.
Rings do occasionally get broken upon instillation ... just saying ...
CJD
Yoda
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Sooty plugs are caused by only 2 conditions. It,s a rich carburetor...which you can rule out since the #2 hole is good. Or...ignition. You are loosing spark to that hole. Even brand new wires and plugs can be defective. Check cap, wire, and plug. On a long shot, if those don't help, look at the distributor point lobe to make sure one is not flat.
Remove the distributor cap and connect the #1 plug to the wire boot (out of the engine). You can then check the resistance from the contact in the cap through to the electrode on the plug. If it seems high, do the same for another wire to compare. While checking this, wiggle the wire in the cap and plug boot to see if you have an intermittent contact.
If all seems good, swap the plug with a good one from a good hole. It could be an internal short in the plug.
It,s good you will be checking the compression, to be sure...but your problem lies in the spark!
John
Remove the distributor cap and connect the #1 plug to the wire boot (out of the engine). You can then check the resistance from the contact in the cap through to the electrode on the plug. If it seems high, do the same for another wire to compare. While checking this, wiggle the wire in the cap and plug boot to see if you have an intermittent contact.
If all seems good, swap the plug with a good one from a good hole. It could be an internal short in the plug.
It,s good you will be checking the compression, to be sure...but your problem lies in the spark!
John
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SUCCESS... at last. And the cure is as mysterious as the problem was.
Here's what has happened.
The car went in for a Spring Tune-up about ten days ago. The mechanics adjusted the valves, put in new points,new distributor cap, new plugs .... and worked on the fuel mixture.
When I got home, I check the plugs -- to put anti-seize on them -- and found that #1 plug was "sooty" or "carbon fouled." All the other plugs were fine.
I checked the #1 lead wire, distributor cap connection, and two or three other possibilities. I put in a new plug, drove 175 miles, and that plug was sooty. I put in another new plug, and it, too, soon became sooty.
Then a week bending the ear of Forum folks with this problem.
In the meanwhile, I studied up on how to balance my carbs and adjust the mixture. I know it sounds easy, but not for a novice like me. I even wrote up a step-by-step manual on how to do it. Got help from the Forum. Thanks.
Today, I worked on the carbs. They were completely out of balance. I balanced them as well as I could with a Unisyn (I couldn't get the little wires in the SU kit to work). Then I adjusted the mixture and carefully adjusted the idle. I then pulled the #1 plug, and cleaned it off, and put it back in. After all that, I hit the road.
Car ran very well. When I returned home, I pulled the #1 plug and it was NORMAL. No carbon fouling or soot.
Don't know why it worked.... but it did!
Any guesses?
Here's what has happened.
The car went in for a Spring Tune-up about ten days ago. The mechanics adjusted the valves, put in new points,new distributor cap, new plugs .... and worked on the fuel mixture.
When I got home, I check the plugs -- to put anti-seize on them -- and found that #1 plug was "sooty" or "carbon fouled." All the other plugs were fine.
I checked the #1 lead wire, distributor cap connection, and two or three other possibilities. I put in a new plug, drove 175 miles, and that plug was sooty. I put in another new plug, and it, too, soon became sooty.
Then a week bending the ear of Forum folks with this problem.
In the meanwhile, I studied up on how to balance my carbs and adjust the mixture. I know it sounds easy, but not for a novice like me. I even wrote up a step-by-step manual on how to do it. Got help from the Forum. Thanks.
Today, I worked on the carbs. They were completely out of balance. I balanced them as well as I could with a Unisyn (I couldn't get the little wires in the SU kit to work). Then I adjusted the mixture and carefully adjusted the idle. I then pulled the #1 plug, and cleaned it off, and put it back in. After all that, I hit the road.
Car ran very well. When I returned home, I pulled the #1 plug and it was NORMAL. No carbon fouling or soot.
Don't know why it worked.... but it did!
Any guesses?
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I absolutly agree, you need to do a leak down test. Of course you need the tester and do it properly of course.But a leakdown tester is pretty cheap on amazon.
If you hear air coming from the exhaust pipe, you have a bad exhaust valve.
Coming from the intake means intake valve is bad.
Air sound coming from the Radiator cap...most likely blown head gasket.
You do the test with the cylinder at TDC on the cpmression stroke so all the valves are closed.
Once you rule out the valves, then you can look at something else.
Mikey
If you hear air coming from the exhaust pipe, you have a bad exhaust valve.
Coming from the intake means intake valve is bad.
Air sound coming from the Radiator cap...most likely blown head gasket.
You do the test with the cylinder at TDC on the cpmression stroke so all the valves are closed.
Once you rule out the valves, then you can look at something else.
Mikey
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Perhaps because there's that balance tube on the manifold (isn't there? I'm working from feeble memory and it's late at night) that -- for the #2 cylinder -- would help negate some of the imbalance between the two carbs? #1, being further away, wouldn't benefit so much.LexTR3 said:
Sounds pretty good, don't it?
