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TR2/3/3A TR3 dead cylinder ?

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wltsii

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working on a recently purchased 1960 TR3 for a friend. No engine history. Plugs, points, condenser, wires, cap all replaced. While running pulled wires one at a time. Number 1 not firing. Pulled plugs, number one soaked all others dry, running a bit rich but not terrible. Checked plug outside cylinder, good spark. Pulled valve cover and checked clearances. # 3 exhaust a bit wide, the rest fine. Ran compression check, #1 135, #2 130, #3 140, #4 130. Running low on ideas shy of pulling the head.
 
number one HT lead duff, breaking down. Could also be a duff plug not sparking under compression.
Used to use a machine years ago that tested plugs, by incrasing pressure in a chmber with a sight glass, could see the spark dissapear as the pressure went up.
 
"Number 1 not firing."

See if the number 1 lead is carrying current. Wear gloves ... and pull the #1 lead off the plug.

While someone cranks the engine (ignition on), hold the lead near the block and see if there's a spark.

Report back!
 
NutmegCT said:
"Number 1 not firing."

See if the number 1 lead is carrying current. Wear gloves ... and pull the #1 lead off the plug.

While someone cranks the engine (ignition on), hold the lead near the block and see if there's a spark.

Report back!
Click to expand...
On some distributor caps a few years ago the #1 plug wire screw connection ( inside the cap) was difficult to get a good connection. Try a pull on the #1 plug wire away from the cap. Or unscrew the #1 wire and reseat the screw into the wire.
Charley
 
I don't recall the "book" compression criteria. Although I don't think your compression is great, it is even, so the issue is spark. Cap, wire or plug are the likely culprits.
Bob
 
my moneys on dizzy cap or HT lead
It has compression, it has suck because the plug was wet, swap two HT leads over see if the fault moves to another cylinder.
 
mezy said:
my moneys on dizzy cap or HT lead
It has compression, it has suck because the plug was wet, swap two HT leads over see if the fault moves to another cylinder.
Click to expand...
I'll check all these ideas on Thursday and report when I get back. Thanks
 
Excellent.

Next, have you checked to ensure the carbs are synched, and the mixtures are equal flats open? If they are, then you can eliminate fuel as a cause and concentrate on the #1 plug wire.

If the carbs are way out of synch and mixtures set differently, you can drive more fuel into one side of the engine and foul the plug.
 
CJD said:
Excellent.

Next, have you checked to ensure the carbs are synched, and the mixtures are equal flats open? If they are, then you can eliminate fuel as a cause and concentrate on the #1 plug wire.

If the carbs are way out of synch and mixtures set differently, you can drive more fuel into one side of the engine and foul the plug.
Click to expand...
I've considered this, and I think the carbs are pretty close, but why only the #1 and not both 1 and 2 ? Carb problems I've had with my Healey usually involved 1 and 2 or 3 and 4.
 
That’s why I asked about your carb synching. It’s possible to shut off one carb , leaving 1 or 2 cylinders running thru the crossover tube. Mixture can go way off, starving or flooding 1 or 2 cylinders. Just a check, so you can rule out a fuel issue.
 
If the car has been standing in a Damp garage for many years, you can get biological growth on the plug leads which hold moisture.
This allows the spark to travel along the path of least resistance.
Clean the leads with some alcohol or brake cleaner, and lubricate them with some light spray oil.
It could be that when you put the lead back in place, the lead becomes in close proximity to earth or another lead which it then tracks down.
. . . Don’t Ask how I know this🙄
Anyway, if your compression ratios are the same across your cylinders, you are basically golden.
They may come up a bit with use.
 
That's a good point...you can learn a lot by looking at your engine run at night with the lights off. It will show you bad connections or arcing right off!
 
CJD said:
That's a good point...you can learn a lot by looking at your engine run at night with the lights off. It will show you bad connections or arcing right off!
Click to expand...
Still have a problem. RECAP--New plugs, new wires, new dist cap, new rotor, new points. Good compression, valve clearances re-checked. Coil swapped out. Floats clearance reset. choke checked. Plug fires outside cylinder. Still not firing in cylinder, #1 comes out wet, 2,3,4, dry.
 
Have you tried swapping the two wire for the one wire and vice versa? I have yet to see anything in this thread to indicate that you have checked the wires. Just because you bought new wires does not mean one of them is not in failure. If this does not identify your problem, put the old cap back on. Just because the cap is new does not mean it is not bad.
Bob
 
bobhustead said:
Have you tried swapping the two wire for the one wire and vice versa? I have yet to see anything in this thread to indicate that you have checked the wires. Just because you bought new wires does not mean one of them is not in failure. If this does not identify your problem, put the old cap back on. Just because the cap is new does not mean it is not bad.
Bob
Click to expand...
I will check tomorrow. You are right, I have had more than 1 new item defective.
 
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