1975 Chrysler 90 HP Fuel Dripping From Carbs

I've got a 90 HP Chrysler on a stand. I hadn't run it in about a year.

I tried cranking it and it won't start. No spark.
Pullled the distributor and removed and cleaned the points, which look like new, but had a film or residue on the contacts.

Tried cranking it again. Plenty of spark, and got it going with a shot of starting fluid. It would not start on it's own.

Once running, it started dripping fuel back out of the carbs. About the same for each carb.

Pulled the distributor again and found I had set the point gap too wide. Reset point gap.

I have not tried it since, but with the gap out of spec about .005", could that cause premature firing and back pressure on the carbs? Thus causing the fuel to drip out?

If not, what are the causes of fuel dripping out of all (3) carbs? Carbs have been cleaned, but not rebuilt.

The motor has good compression and sounds strong when revved a bit.

Apparent fuel leak has nothing to do with ignition.-----------------What angle is the motor hanging at on the stand ???----------Put it on a boat and see what it does.

Yes, the carbs are tilted forward a bit due to the where the tilt and trim was set. I'll wire the tilt/trim back up and drop the motor and retry it.

Attached is a photo showing carbs tilted forward a bit.

Follow-up:

I wired up the tilt and trim and tilted the motor back to a more normal operating position.

Turned on the muffs, pumped the bulb up, hit the chokes and it fired off with no fuel dripping from the the intakes of the carbs. It starts quite well now.

After running it a few seconds, it started pouring fuel from a small orfice on top of the top carb. It was not doing it from the other two. I readjusted the idle screws to 1 1/2 turns out (were set at 1 turn out) and that reduced the fuel coming out of the orfice. (However, the exhaust started smoking a lot)

I looked in the Clymers manual and it does not have anything on that hole where the fuel is leaking. Not even an illustration. See attached photo with arrow.

Anyone know what this is for (vent?) and what is causing fuel to come out?

Got another question on this 90 HP Chrysler:

With the key off, I'll connect the positive cable to the battery and there is a spark as I connect it.

Is that normal? Is that the ignition system using the voltage immediately?

No it's not using it as soon as you hook it up unless the key is on.
Your radio/lights/depth finder/bildge pump.Might be hooked up.
The hole is the overflow.When the float/needle valve stick it comes out there.J

Thanks for the reply, jerryjerry.

Yes, it's possibly a stuck needle valve or trash. (I do have a clear inline filter between the pump and the carbs, now)

As for the electrical, the motor is on a stand, not in a boat. No accessories connected to the battery.

It may be a short or something. I'll have to track that down if it is.

on the right track for sure

Okay, I tried some things on the electrical system to see where the spark is coming from.

After it set overnight, I reconnected the positive cable and it sparked as I connected it. I immediately remove the positive cable and then reconnected it. No spark. (The ignition system is a MagnaPower CD with ignition points.) The Clymer manual I have states this is a capacitive-discharge system and the CD stores battery voltage. So, I believe when first connected, the battery cable will spark because the capacitor is drawing voltage to store.

I have been wrong about how to connect and disconnect a battery. The negative post is suppose to be removed first, not the positive, according to Clymer. I've been leaving the negative on and removing just the positive. That is the wrong way to do it.

Follow-up on fuel leak:

I removed the top carb and removed the bowl. The float and needle were stuck all the way down.

I removed the float and the needle was tight and jammed in the needle seat body. I pulled it out and found it would get into a bind easily when moving it by hand. The float level was checked, the float drop was checked. I reread the spec on for the float on this type carb (Tillotson WB21A) and imho, the float drop seems to be excessive. I set the tang so the float would not drop as much.

The carb was re-assembled and installed on the motor. At the time of assembly the float and seat appeared to be working fine.

The fuel was pumped up, muff water turned on, hit the choke and the motor fired right up and ran well for a few minutes. Then the fuel started spitting out the vent hole again, but not as bad as before. The engine started idling a bit rough and then did a sudden stop, almost like it locked up. But it wasn't locked up It restarted immendiately and ran for a few minutes then did the same thing.

The only thing I can think of is the top cylinder is getting hydraulic lock from excessive amounts of fuel????

The top carb is going to need a new needle and seat. There is something not right about it to keep sticking open.

Sidebar:

On page 175 of the Clymer Chrysler Outboard Shop Manual, Fifth Edition, Eighth Printing, May, 2004, there appears to be an error in the illustration. The float (Item 14) is shown upside down with the tang facing down instead of towards the needle seat.

Just thought I'd pass that along.

No such thing as hydro/fuel lock.
The fuel system needs to be cleaned.What did you use to clean it?
Have you checked the fuel pump diaphram?There is a filter in the fuel pump,how dirty is the filter?
Wal mart sells an inline filter.$3 #12 filter.It's a small partical filter,install it between the carb and the pump.Or anywhere in the system after the squeezie.

The needle/and seat,some have rubber tips and a rubber O-ring in the seat, that the ethanol is delaminating/destroying,melting and the seal is leaking.
Look REAL close at these.

The fuel system has all new lines, clean external tank, fresh fuel, new pump diaphram, new filter (clear plastic) between the pump and the carbs. Each carb was taken apart and cleaned in carb cleaner, re-assembled checking the float level. One of the needles had the neoprene tip. It was replaced with a new all metal needle/seat. (I don't remember if the top carb got the new needle/seat.)

The needle/seat that's sticking (top carb) is all metal and appears to be binding in the bore somehow. There are no apparent defects in either. I put them under a magnifying glass. I'm using non-ethanol fuel.

The abrupt motor stoppage is still a mystery to me.

I'm getting pricing and shipping on some new needle and seats.

Problem Solved.

I received the (2) new Quicksilver needle & seats and installed one in the dripping top carb.
(BTW, the old needle was stuck when I took the carb apart. The bore of the old seat is really rough for some reason unknown)

The float level and float drop were reset to spec.

Installed it back on the motor. Pumped the bulb, turned on the muffs, hit the choke and it fired right off.

No more dripping out the bowl vent hole. The engine has not run better since I bought it.

Two things it needed to fix the drip:

1. The motor was angle up too much and had to be lowered with the lift/trim. When testing a motor on a stand, the motor works better if it sets like it would on a boat. This fixed the fuel dripping out the front of the carbs.

2. The needle/seat that came with the motor was bad. A new set fixed the fuel drip from the bowl vent.

Another BTW: By connecting the positive post to the battery first, then the negative, I experienced no spark when connecting the terminal.

The motor starts just great and runs smooth.

Now I need a boat for it........