1974 Chrysler 75hp PROBLEM!

[taittinger]

I gotta 74 chrysler 75hp and it is acting up. it will start and idle like a champ all day. But when i take it to the water it runs like fine, until about a mile or 2 up the river and it spits and spudders and shuts off and wont fire until later. im thinking its over heating but why? PLEASE HELP! i would like to go fishing and actually get back to shore without being towed back

thanks
Frankie

 

[7355hpchry]

Re: 1974 Chrysler 75hp PROBLEM!

Did you check the vent hole in your gas cap? Is the ball getting flat? If it is an overheat problem its most likely the water pump impeller.

 

[Frank Acampora]

Re: 1974 Chrysler 75hp PROBLEM!

It doesn't sound like overheating. When an engine stalls due to overheating, it will slow down and "harden" to a stop, no spitting or shaking. Usually, when stalled due to overheating, damage has been done (at least to the head gasket) and future starting may be more difficult. You can usually smell baked paint from stalling due to overheating and smoke may be visible.

You should check your fuel supply. Be absolutely certain that enough fuel is being delivered to the carbs at high speed. Check the usual: Fuel pump diaphragm, fuel lines, primer bulb, quick-connects, and tank.

If you do not have an electronic distributor, check the capacitor inside the dist. (if you have one) If that appears ok, then look under the flywheel at the rear where the wires pass over the block going to the electronics. There is no shrouding there and sometimes during running a wire will bounce up and rub on the underside of the flywheel. When the insulation rubs off, the wire will short and pop the circuit breaker at the base of the terminal board near the starter. Then, you will not be able to start until the breaker cools and resets itself in five or ten minutes.

 

[taittinger]

Re: 1974 Chrysler 75hp PROBLEM!

the balls hard and it doesnt smoke and i cant smell any sort of burning. the last time i drove it i got up the river to the normal break down spot and it quit. i let it sit for a while, it started up after about 20 mins of cranking. i make it 100 yards or so and it would spit and spudder so i let off the throttle and it would clear up for a second then bog down. when it did that i gave it full throttle and it would clear up for 50 yards and quit. could my fuel/oil mixture be to lean or rich? if so, wat damage would be caused if it wasnt mixed correctly. obviously too much oil wouldnt hurt it, it would just smoke alot and wouldnt be up to par. but if it is too rich?, could i have fried the rings? maybe a head gasket? PLEASE HELP! its soooo frustrating

 

[Frank Acampora]

Re: 1974 Chrysler 75hp PROBLEM!

I'm thinking!

Some of the symptoms sound electrical and some sound fuel related.

SO: Since the fuel system is easiest to check I would first look at it from the tank right to the carbs. As a matter of course, replace the fuel pump diaphragm and gasket. Clean the carbs. A sticking float can cause erratic running.

Once you get the fuel delivery system perfect, then check electrical.

Look on the auctions or go over to The Chrysler Crew and get a manual. It will be the best investment you can make .

 

[taittinger]

Re: 1974 Chrysler 75hp PROBLEM!

this is my first boat owned so this is all new to me. the guy i bought it from said he had justed changed the fuel pump and water pump. but ill check it out. i have a manual. but like i asked earlier. could me mixture be too rich or lean? which ever it is with more gas than oil

 

[Frank Acampora]

Re: 1974 Chrysler 75hp PROBLEM!

Fuel mixture should be 50 to 1 or 1 pint oil for 6 gallons of gasoline (48-1).
Deviating from this mixture will not cause major problems as long as it is not too far off. Doubling the oil is usually recommended for break-in so aside from being a bit smoky and fouling plugs, it does no harm. Halving the oil will usually be acceptable for short periods, but for continued use, it will eventually cause corrosion problems inside the engine. At any rate, varying the oil mixture from 50-1 SHOULD not cause the type of problem you are experiencing.

HOWEVER: Be certain to use TCW III oil. (Two Cycle, Water cooled) Any brand will do. Do not use regular multi-weight automobile oil. It contains additives harmful to two cycle engines.

Again, buy a manual. Most mechanics will refuse to work on an engine that old. So to keep yourself from being their mercy and to be a bit independant, learn to fix things yourself. It can be very satisfying and cost effective.

You would be surprised: With the correct attitude , the manual, and a few tools, most repairs and maintenance tasks are easy--most anyone can do them.

 

[taittinger]

Re: 1974 Chrysler 75hp PROBLEM!

wow thanks. that helps alot. i am good mechanic, i just dont kno about these outboards. i usually work on my race snowmobiles or my race/derby cars but wat if i were to say i didnt mix the gas at all.. wat would happen to the engine?

 

[taittinger]

Re: 1974 Chrysler 75hp PROBLEM!

could this be a coil problem?

 

[Skiwi]

Re: 1974 Chrysler 75hp PROBLEM!

wow thanks. that helps alot. i am good mechanic, i just dont kno about these outboards. i usually work on my race snowmobiles or my race/derby cars but wat if i were to say i didnt mix the gas at all.. wat would happen to the engine?

If your still around.... then to answer the red portion or your question, not adding any oil would have catastrophic consequences

 

[TalonTurbo]

Re: 1974 Chrysler 75hp PROBLEM!

the balls hard and it doesnt smoke and i cant smell any sort of burning. the last time i drove it i got up the river to the normal break down spot and it quit. i let it sit for a while, it started up after about 20 mins of cranking. i make it 100 yards or so and it would spit and spudder so i let off the throttle and it would clear up for a second then bog down. when it did that i gave it full throttle and it would clear up for 50 yards and quit. could my fuel/oil mixture be to lean or rich? if so, wat damage would be caused if it wasnt mixed correctly. obviously too much oil wouldnt hurt it, it would just smoke alot and wouldnt be up to par. but if it is too rich?, could i have fried the rings? maybe a head gasket? PLEASE HELP! its soooo frustrating

I am a NOVICE really to outboards, but do have SOME experience with 2-stroke. Too much injection oil/or too little injection oil is dangerous for the engine. 2 stroke motors CAN run lean with TOO much injection oil mixed in ... the fuel/air ratio changes with the mixture rate ... I cannot be sure but with cars we want to run 12-14:1 fuel/air .... if there is too much oil in the mixture you may BUMP the mixture to 15 or 16:1 A:F ..... Just my 1/2 of 1 cent ....