45 Chrysler won't idle

[dj-boat]

I have a 1970 455HA 45HP Chrysler Magneto that I purchased as a project last fall. I went through and replaced/fixed the following things.

1) New gas tank and gas tubing.
2) I went through all the wiring and cleaned it up.
3) I changed the points/condensers and gapped them per spec (per Seloc Manual).
4) New spark plugs, gapped per spec.
5) I bought a carb kit, cleaned and replaced parts in the carb. Adjusted float per spec.

I got running last fall. It would start right up but I didn?t keep it running more than a couple of seconds because I didn?t trust the impeller.

I had it in my basement all winter. I took apart the lower unit and replaced any worn parts. When I first put on the boat last weekend, it started right up in the bucket. I took it out to the lake and it started right up there. After idling for a while it stalled. I could get it started again but only if I increased the throttle. I drove it around and the RPM?s fluctuated with constant throttle position. Also, there was considerably more smoke coming out of the exhaust when I went slower (not sure if that means anything and I am using 50:1 ratio). It never stayed running for more than a few seconds while in neutral or low RPM.

I am planning to get a fuel put diaphragm but was wondering if there is something else I should be looking at. The plug wires aren't great but since they are part of the coil, I left them on for now. It?s kind of hard finding parts for the old girl.

 

[Frank Acampora]

Re: 45 Chrysler won't idle

Just to reiterate: Points gapped at .020, plugs at (I think) .030. Set idle speed to 700-750 in forward gear, in the water, by using the stop screw on the timing tower.

To cold start, pull out the silver knob on the control box and advance the throttle lever until it stops. This is fast idle/start/warm-up position. Once started and warmed, return lever to neutral and push in the knob. Now the control box will shift the engine into gear.

Your ignition switch is push to choke. You must hold it in while cranking to choke the engine for a cold start.

Varying RPM at a given throttle setting usually is a fuel problem however it could also be clogged oil recirculation system. Clean the screens on the plate on the side of the engine block that the shift lever attaches to. Be certain that the carb is not set too lean on the low speed needle (in front of the carb) Should be about 1 turn out from lightly seated. Lightly seated means that you turn in the needle with a small screwdriver until it just bottoms and stops. You don't force it. Too much pressure will deform the needle and carb seat.

These engines always smoke especially during low speed. At low speed, the boat is not moving away from the smoke and you notice it more. 50-1 is the correct ratio.

 

[dj-boat]

Re: 45 Chrysler won't idle

Well I took the fuel pump off and changed the diaphram. I also cleaned the screen and changed the gasket for the glass bowl. I was very careful with all of the parts to make sure nothing was misplace or mishandled. This included the one valve that is not pressed in. I put it all back together and now it won't start at all. It doesn't even catch. When I prime with the ball, i can see gas going to the carb. I checked the spark to make sure it was getting a spark just to eliminate that. I'm not sure what I would have done to make it worse. I've been going over everything I did and my instict is to take the fuel pump apart but I hate to do that if there is something else I am overlooking.

 

[dj-boat]

Re: 45 Chrysler won't idle

One other thing I forgot to mention is that I disconnected the fuel line at the carb to make sure it was getting fuel when I turn it over.

 

[jerryjerry05]

Re: 45 Chrysler won't idle

Choke operating?
Sometimes when you clean the carb and fiddle with the needle valve it will hang up.
It usually doesn't require ANY float adjusting.You might have adjusted it shut.
Try tilting the motor up all the way and starting it there.As soon as it starts/coughs/gags shut it off.Lower it and try starting again.This allows the gas past the needle and will possibly allow starting. J

 

[dj-boat]

Re: 45 Chrysler won't idle

Not sure why but it started up today. I thought it might have been flooded yesterday and let it sit for a long time between attempted starts. I took it out on the lake today and it ran a lot better. It still acted a little funny with the throttle. I looked and found a break in the control cable. Going to order one now and hopefully thats all it needs. Thanks for the help.