1973 Evinrude Ignition problem

[oldboat1]

I would like to define what I said in my last post. When I was running the motor and did the carb idle mixture screw adjustment, when it was turned in, the motor would want to die/stall and when I would turn the screw out the motor ran rough.

sounds normal (idle mix adjustment).

 

[clanton]

Compression test ? Connect peak reading meter to ignition coil hot side, each time it mis fires, meter should dip,

 

[geoffwga1]

Check the needle packing.

 

[geoffwga1]

check the needle packing

 

[DarleneD]

I got a few suggestions, to check the needle packing, do a compression test, and do a peak voltage reading at the coil. Here is what I have done to update everyone.
1. compression test is #1 cylinder 110 psi and #2 cylinder is 115 psi.
2. Tested the coils and wires, the charge coil and sensor under the flywheel..all are ok.
3. Re-did the ign spark gap test, and the book said do it at 1/2" and is good
4. when I last did the carb clean out, all o rings and gaskets and needle were replaced and appear to still be ok.
5. I did not do "peak reading meter to ignition coil hot side" because I was looking in the book several pages in and found another test to do. This part was called "Index flywheel, erratic ignition" (see photo). I followed the instructions and actually found a problem. Basically the test is to index each cylinder to a fixed mark on the motor, then start it and using a timing light hook up to each cylinder separately and watch the mark I made for the specific cylinder. According to the book I should only see the cylinder I am connected to firing. Cylinder one I saw only that one firing as it should, BUT when connected to cylinder 2, I saw that I was getting a flash from both cylinders a the same time. Basically when it fired #2, immediately I saw #1 flash right over the #2 mark. I took video of this if anyone would like me to send a copy

According to the book, it could either be bad coil wires or CD unit. Earlier I did try another cd unit and nothing changed. I did order another new one and I will try it when it comes. I will let all know how it turns out. I hope this is it.

 

[oldboat1]

Might try reassembling the coil wire assembly. Make sure each spring clip contacts the wire core.

 

[DarleneD]

I have replaced the coil wires with known good ones during the process. These coils have the short pre-made coil wires with the boots on both ends. I installed a new CD unit and fired up the motor and there was (believe it or not) no change. It still did the erratic type of firing. Even when the timing light was used, I got the same reaction as before.

 

[racerone]

I can believe that there was no change !----Throwing parts at it can get expensive.-----Check to see that throttle plate is opening at the correct time.

 

[DarleneD]

Well, I took the time today to see if the throttle plate is opening at the correct time and it is correct. What is strange is that this problem just started up one day. After removing the carburetor and cleaning it three times and now checking the throttle settings both at idle and full throttle, the issue has not changed at all.

 

[F_R]

Cleaned the carburetor 3 times? Just goes to prove what I'm fond of saying. "Most carburetor problems are not". Not criticizing you, just sayin' to benefit others that are so quick to attack the carburetor, no matter what the problem really is.

Here's hoping you find what that real problem is. I don't know.

 

[oldboat1]

Fact is, have to work on all the systems in restoring a motor. On the ‘50s motors I like to work on, it’s about $130 for parts — cooling system first, but other than that take your pick where to start.

 

[tomhath]

According to the book I should only see the cylinder I am connected to firing. Cylinder one I saw only that one firing as it should, BUT when connected to cylinder 2, I saw that I was getting a flash from both cylinders a the same time. Basically when it fired #2, immediately I saw #1 flash right over the #2 mark.

That sure sounds like it's arcing across the plug wires. But you said you've replaced the wires and plugs. What happens if you run it with only one wire at a time attached? It should run fine on #1 and have the miss on #2.

 

[DarleneD]

QUOTE: "Cleaned the carburetor 3 times? Just goes to prove what I'm fond of saying. "Most carburetor problems are not". Not criticizing you, just sayin' to benefit others that are so quick to attack the carburetor, no matter what the problem really is"

Had a motor that did this similar problem in the past and cleaned out the carb and it works fine, so based on that I thought it was the same type of problem. Then others suggested re-clean the carb, check throttle adjustments and so on. I had nothing to loose, so I am trying any suggestions to resolve the problem. To me it seams that it is a lean fire issue, and that says carb to me, but after cleaning it several times and no change, hummm? While running the engine, I left the manual choke open (push/pull plunger type) during running to see if any difference (no change) as the book says for warm up, then it says to push it in completely when warmed up.

I even disconnected the manual choke from the system when running the motor and again no change. At one point earlier, I took off the carb, and the reed /intake manifold and inspected the reeds and naturally they are good.

 

[DarleneD]

QUOTE: "That sure sounds like it's arcing across the plug wires. But you said you've replaced the wires and plugs. What happens if you run it with only one wire at a time attached? It should run fine on #1 and have the miss on #2."

Never thought of that.... I will give this a try and post results asap. Thanks

 

[DarleneD]

Its been a while, but trying to figure out the problem had me stumped. I decided to locate a good used carburetor and found one. I installed it just as it was delivered to me. Got the motor started and guess what..... the problem went away. There is no miss or belch, or burp now. Runs and starts with no problem.

I would like to say to all those who gave me ideas, and or suggestions with this problem thanks. Maybe some day I may be able to help someone.

 

[54bobby]

i'm curious as to what in the carb led to the problems. with out reading the entire thread, and not knowing whether a carb rebuild was done i do know that there is a small very overlookable gasket/bushing that goes deep inside the low speed adjustment orifice that usually don't come out on it's own. and if replaced should be replaced along with the needle itself as they are a matched pair and groves on 1 or the other match up with the opposite. so if not replaced together ur installing 1 or the other where the ware don't match up. same goes with the float needle valve and seat.