1973 55hp chrysler timing and carb

[kjburr]

Hi. I was wondering if anyone knew how to set the idle timing screw and carb adjustments on this motor?

 

[kjburr]

Re: 1973 55hp chrysler timing and carb

On another question is 65 compression on each cylinder normal for this motor?

 

[kjburr]

Re: 1973 55hp chrysler im stumped

Re: 1973 55hp chrysler im stumped

This has me stumped. It turns out the compression is ok. both cylinders are running about 150-152 compression. I cant seem to get the top cylinder to fire though. Heres what I have tried. I've tried taking the bottom cylinder plug wire off and just running the top cylinder. Well it will not fire a lick! I tried just running the bottom cylinder. Starts right up! I tried using the top plug wire on the bottom cylinder. It back fires! Tried swapping the spark plugs with each other, no change. So my question is what in the world is missing everything seems to be there. My only guess is that, well, I put alot of sea foam in the top cylinder and hardly much in the bottom. I have run the motor at WOT when playing with the carbs and I thought that would have took care of the sea foam, unless it was running on one cylinder the entire time. Any ideas??

 

[Frank Acampora]

Re: 1973 55hp chrysler timing and carb

Of course it will backfire when you switch the wire-it is now 180 degrees out of time. However, that shows that you have some spark on the top. Perhaps not enough to run though. You do not say exactly which 55 it is. Chrysler did make a twin carb 55 for a while. If this is a single carb 55, it won't matter if it is magneto or battery and coils ignition.

So, try this: Disconnect the fuel to the carb. remove both plugs and clean them. Put about 1 teaspoonful of fuel/oil mix in each plug hole--this will flood the engine. Crank until it fires. If it still fires on one cylinder, then fuel delivery is not the problem. Pull the flywheel and clean and set the points to .020 set each point at the mark on the cam--there should be one. Be precise since a difference of only .0015 at the points is one degree timing.

 

[kjburr]

Re: 1973 55hp chrysler timing and carb

This is just the single carb magneto ign. I was browsing iboats for spark plugs on this motor and it seems I have the wrong ones. I currently have on the motor NGK BUHW and it takes NGK BUHX. I wonder if this would cause this type of problem. I am still going to clean and and set the points just for preference. I noticed that the spark plug on top kept dry. I will try the teaspoon with gas and see if that is the problem. I will post back after I have done this.

 

[kjburr]

Re: 1973 55hp chrysler timing and carb

well I cleaned the points and regapped them with no apparent change. We tested the plug wire with a test light and the wire is getting good spark on both wires. Well when we hold the spark plug to the engine block(the top coil)it doesnt show spark. I am not sure about the bottom one as it seems to always fire anyway. I dumped gas in the cylinder and it wont fire still. It seems to be losing spark between the spark plug wire and the spark plug. I am definately guessing its the plugs. Maybe the magneto ign is picky with the plugs.. thanks and if any other advise id appreciate!

EDIT: I am thinking maybe the top coil isnt producing enough spark through the wire still even after cleaning.

Does this thing run on one cylinder while idling and the other cylinder kick in when throttling? I am starting to beleive this may be the case.

 

[kjburr]

Re: 1973 55hp chrysler timing and carb

I just recently tried some L82C champion plugs with no change either and this is one of the correct plugs for this engine.. although there is a standard type and a resistor type, L82C and QL82C. I wonder if I need the QL82C. My question remains. Does this thing run on one cylinder at idle, and the other cylinder kicks in in gear?

 

[kjburr]

Re: 1973 55hp chrysler timing and carb

do you think a new coil would do the trick?

 

[thompy]

Re: 1973 55hp chrysler timing and carb

that sounds like your problem, can you chek the resistance in the plug wires

 

[kjburr]

Re: 1973 55hp chrysler timing and carb

I checked for spark with the spark plugs against the block again, and the top plug isnt getting a very bright spark, but it is getting spark. This brings me to the assumption that the coil is weak an will need to be replaced. Does anyone know where to get the magneto coils for this motor?

 

[Frank Acampora]

Re: 1973 55hp chrysler timing and carb

Before you buy a 40 or 50 buck coil, try replacing the capacitor. Franz at franzmarine@aol.com should have capacitors. Coils can be bought at standard magneto 1 800 624-6386, probably cheaper than Franz.

 

[kjburr]

Re: 1973 55hp chrysler timing and carb

Well. The reason I dont beleive it to be the capacitor is because, well, heres what i did. I got the engine running on the bottom cylinder and check for spark that way with the top cylinder and thats when it still showed weak spark. I did notice the magnet was beat up on this coil. I am not sure if this is a big deal though as its just a magnet that goes through the coil. Can you replace the plug wires that go to these coils, as they seem permanetly attatched?

 

[kjburr]

Re: 1973 55hp chrysler timing and carb

would the capacitor be the same thing as the condensor on this motor?