Chrysler 55 one cylinder occasionally fires

[The_Original_TEE]

Hi there

To start, I’m new to the forum, boats and outboards. I recently got a boat with a Chrysler 55 on it. Model 5542 sn 2105. I don’t know the year but if someone can tell me I’m interested.

On its maiden voyage it got me around the lake okay but on the way back to the boat launch it fired up for a couples seconds and then powered down again.

The boat runs and idles but it seems only the bottom cylinder is running consistently. I checked the top plug and it’s got a spark. I pulled the plug and there is a spark. I can’t say for sure if it was strong blue or not. I didn’t take a good look but I should/will. When fiddling, I had disconnected the spark plug cable from the top plug and can feel it sparking through me. When I go to reconnect, as the connector gets real close to the plug the cylinder fires up but it stops when I connect it. I was able to hold the cable very close to the end of the plug and it was firing but would stop once I connected it.

Hoping for some suggestion on what is causing it.

Bought it used and and it had not been running for a couple years. Replaced old gas with premium at about 35:1 or so. It’s got some other issues but I’d like to figure this one out.

I was going to do a sea foam shock on it but thought I’d ask the smart people what they think.

I added a couple pics because who doesn’t love pics.

Please help

 

[Nordin]

Your model number must be missing one digit.
5542(8) is 1968 year model and looking at the pics the top cowl is one from 1968.
1968 was the year Chrysler introduced the 55Hp.
Concerning your ignition issue you have to check out the ignition system.
The 1968 year model of the 55Hp had two different ignition system, magneto and battery.
Magneto you have the ignition coils under the flywheel, battery system the coils are mounted outside the power head.
Check all wirings, clean the points and set them to 020 in for the magneto and 015 for the battery system.
Check the HT wires for cracks or bad insulation, check the plug rubber boots for cracks and the spring inside the rubber boot for rust.

 

[jerryjerry05]

Pics(we love pics) more pics with the cowl off.
If the points haven't been serviced that could be the problem.

 

[The_Original_TEE]

Hey thanks for the quick responses. It must be a Magneto as the wires lead up under the flywheel. Is there any instructional guides you could recommend on checking the points and… what am I checking. Pretend like I know nothing about ignition because .. humbly I do not. I can get some more pics later today but here is one I took of the plate under the cowl. If it’s missing a number I don’t see any clues as to what it’s missing. Still learning, please be patient and thanks so much.

Something to add is that the boat came with most of a Chrysler 35 including lower. I’ve pulled the carb off of that one and cleaned it up. I was thinking of swapping it out as well. I haven’t pulled or cleaned up the 55 carb yet but did adjust it and it seems to run best at just over one turn out. But that’s still only one cylinder.

 

[Nordin]

I can imagine a digit to the right of the digit 2 but can not tell what digit.
If you are not familiar with ignition system it is hard to give you advise, but I will try.
First of all pull the flywheel and check the surface of the points and clean it with fine water grind paper (400 grid or higher).
Set the points gap to 020 in with the points at highest point of the cam.
Use a feeler gauge to adjust, it should be just snug.
Check the HT wires, spark plug boots for bad insulation and the spring inside the boot from rust.
Then try it for spark, BUT you have to torque the flywheel nut to right spec value otherwise you maybe share the flywheel key.

 

[jerryjerry05]

Reading the tag: no other numbers that I see. From the number that I do see it seems to be a 69-71
Pull the flywheel and file the points, do the set that's not firing too.

 

[jimmbo]

You say the one Cylinder will fire, until the wire/boot is placed on the Plug?
Maybe there is a Carbon Track or Crack in the Porcelain. Try a new Plug. Also try to clean the inside of the Boot of any carbon/dirt

 

[The_Original_TEE]

Thanks everyone, before I remove the flywheel Is there anything I should know about putting it back on? Do you think the odd serial number is because it's from Canada?

I do have a 55 manual of some sort and it covers the flywheel but I don’t want to mess it up.

 

[brodmann]

You say there is spark until the wire touches the plug. That's how it works. The spark is an electrical arc. If the wire is touching the plug, there will be no arc. Also, you say it's running on one cylinder. I wouldn't run it any more until you know for sure it's not a carburetor issue. If it's a fuel problem, and one cylinder is not getting gas, it's also not getting oil! You can do big damage if you run it with one cylinder running dry.

 

[jimmbo]

Based on the lack of an 8 in the model #, I would say that your motor is a 1969

5542
55 55hp
4 is for 15" Shaft, Electric Start
2 is Canadian Manufactured

 

[jerryjerry05]

Don't worry about the missing #
The years: your #s fit right in there. so a 68 or 69 is when your motor is made.

55	1968	55728
55	1969	5545

 

[The_Original_TEE]

Thanks everyone for the information. I think the I'd like to pull the flywheel and address the points, I think it maybe the right path. Is there anything I need to know about pulling it or is there anything I need to know about putting it back on? Do I need to mark any kind of location to ensure it goes on right? I have this from the service manual I found but I don't know if it truely matches the model I have.

Thanks again for being patient as I learn.

 

[Nordin]

Follow the service manual, it applies all 55Hp models.
The purpose of the flywheel key is to locate the flywheel to the crank shaft, the taper and the nut are for holding the flywheel in place.
Important when assembling is to lap the taper and flywheel, check that the key fits in the grove properly and to torque the nut to right spec.

 

[The_Original_TEE]

Thanks! Do you know that the torque required for this is? I can’t seem to find that in the manual.

 

[Nordin]

I do not have my workshop manual here right now (I am on vacation) but I think it is about 120 Nm (90ft lbs).

 

[The_Original_TEE]

Well here she is without the cowl off. I didn't get much done other than taking a few pics and testing further. Progress is a bit slow since it summer and I need to spend family time. I also tried to post a vid of it starting up and running.

I tried briefly to pop the fly wheel nut off but it wouldn't release without turning the flywheel. I will try again later.... admittedly, I didn't try that hard last night.

@Brodman It's getting gas (and oil) as I can get it to run at will by fiddling with the cable. My guess is points first and coil second as suggested since it seems to be arching the gap between the between the plug terminal and the wire when I do get it to run. I'll try to get a video of this to show you soon, or if I get the flywheel off and can clean up the points and set the .020 gap, I'll show results.

 

[jimmbo]

Looking at the pics and images, I would be checking the Upper Bearing Seals, as I see what looks like a dusty oily mess coming from that area

 

[The_Original_TEE]

Looking at the pics and images, I would be checking the Upper Bearing Seals, as I see what looks like a dusty oily mess coming from that area

Thanks Jimmbo, there is a significant list of things I'll need to check and add this. There is a chance that someone just greased the hell out of everything. also need to look at linkage as well lower seals..

She's older than I am and there is lots I don't know about it. One thing at a time though, and for now I'd like to figure out the ignition issue in the upper cylinder.

 

[jimmbo]

Perhaps the Issue is one Cylinder running Lean, and miss. A leaky Crankshaft Seal can cause the upper Cylinder to do that, as well as provide an Oil Bath

 

[The_Original_TEE]

Perhaps the Issue is one Cylinder running Lean, and miss. A leaky Crankshaft Seal can cause the upper Cylinder to do that, as well as provide an Oil Bath

Thanks jimmbo, I can consider it once I know the points are set correctly. .. and when I can learn how to do that