Johnson 1960 or 1962 55hp outboard making weird noises when Throttle is pushed down.

[MrFishy]

Just bought a 1960 Glasstron with a 1962 Johnson 55hp outboard. I had the oil changed and water pump kit replaced. Boat was working fine for the first couple outings. Went out fishing in the kelps yesterday. Chopped up some kelp with the propeller and I think I over worked the motor. On the way back when I pushed down on the throttle the engine started to make noises and wouldn't accelerate past a low speed. Im also not sure if the water pump is working properly. Does this type of motor have a streaming line of water thats supposed to **** out? When we got to the dock I took off the cap and touched the top of the motor. It was very hot! Before I call a mechanic and "BOAT" BRING ON ANOTHER THOUSAND I thought i might pic away at the forums guru's.

 

[Daviet]

Re: Johnson 1960 or 1962 55hp outboard making weird noises when Throttle is pushed do

That's not a 1962 engine, can you post a model number?

 

[jimmbo]

Re: Johnson 1960 or 1962 55hp outboard making weird noises when Throttle is pushed do

It is either a 1968 or 69 3 cylinder 55hp. That engine does not have a water tell tale. while you were kelp chopping you might have inadvertently clogged the water intakes, posibbly overheating the engine. That engine did have an overheat horn in the control box, they used to be load enough to make you want to jump out of the boat. It might not work 40 yrs later or the sensor disconnected. How hot? too hot to hold your hand on it? if so you might have problem. Pull the leg and inspect the pump impeller, if it was deproived of water it will be pooched. Compression checks are also needed.

 

[MrFishy]

Re: Johnson 1960 or 1962 55hp outboard making weird noises when Throttle is pushed do

The overheat control box is still there I believe the sensors are disconnected. It was hot but i could of kept my hand on it. By leg do you mean the lower unit lol? This is my first boat and Im not familiar with all the parts yet.

 

[MrFishy]

Re: Johnson 1960 or 1962 55hp outboard making weird noises when Throttle is pushed do

Here are a few images of the boat. Im the 3rd owner according to the last person I bought it from. The boat seems to have all its original emblems and paint.

 

[jimmbo]

Re: Johnson 1960 or 1962 55hp outboard making weird noises when Throttle is pushed do

It is a 1968 longshaft. When I said leg I meant the lower unit. It is a Hyrdo-electic shift model. If the wires were disconnected the horn wouldn't sound. Your engine will have a couple of temp sensors on it, one for the overheat and one to control the automatic choke. As I said you should inspect and probably replace the impeller and any other worn/damaged parts of the water pump. You said the motor did have some issues running. I would start with a compression check

 

[MrFishy]

Re: Johnson 1960 or 1962 55hp outboard making weird noises when Throttle is pushed do

I will be taking it apart tonight and will post pictures. Thanks for the advice. Keep you posted...

 

[MrFishy]

Re: Johnson 1960 or 1962 55hp outboard making weird noises when Throttle is pushed do

The water pump impeller and the whole kit was replaced less than a month ago and still are in new condition. The compression check came out to 125 on all three plugs. There seems to be water entering the lower unit. Going to replace the thermostat as well. Not sure why the water isnt pumping through it corretly. any other suggestions?

 

[jimmbo]

Re: Johnson 1960 or 1962 55hp outboard making weird noises when Throttle is pushed do

You said the motor started making noises when you tried to accellerate. What kind of noises? You said the engine was still cool enough to hold your hand against the top of the block. Tempwise it might be fine. Have you checked the overheat circut for continuity? One thing a lot of people do not realize it the thermostat really only conrtols water flow and temp at idle and low engine speeds. At higher speeds the waterflow and pressure is great enough to unseat a pressure valve allowing more waterflow.

 

[MrFishy]

Re: Johnson 1960 or 1962 55hp outboard making weird noises when Throttle is pushed do

When I push down on the throttle it accelerates smoothly at 5 knots but when pushed past that it starts to make a choking noise like its trying to go faster but cant. Im going to be replacing the thermostat hoping it will fix the problem. I do not know where the overheat circuit is!? When I first changed out the water pump kit and put the clamps on to test the water flow it had a nice flow, but know it doesn't flow the same way.

 

[jimmbo]

Re: Johnson 1960 or 1962 55hp outboard making weird noises when Throttle is pushed do

On the water pump. You said you were chopping kelp, i will assume you meant you were in the weeds and they were all over thr gear housing. There is a chance the water inlets were clogged or blocked by fore mantioned weeds. If the water pump is totally starved of water damage will occur to the impeller.
The choking/lack of power could be many issues. Fuel and spark come to mind. Have you checked to see if you have spark on all cylinders? A chokes valves fully open? Take the cover of the air box off and look. Also check to make sure all the carbs throttle plates are linked together and move when throttle is advanced. After you have verified the cooling system is fine run the engine, preferably at the lake where it can be put in gear. With cover and airbox cover off have some driving the boat attempt to speed up. If the motor does the choking thing spray a bit of mixed fuel into each carb if the motor speeds up you have a fuel starvation issue, if if bogs worse it might be flooding.

 

[MrFishy]

Re: Johnson 1960 or 1962 55hp outboard making weird noises when Throttle is pushed do



That is what it looks like inside the thermostat. The guy working on the boat is switching out the thermostat, but I have a feeling there's a bigger problem than just that :facepalm: How do I check for spark on the cylinders? What does a choke valve look like? Im going to print out your post and read it to my mechanic.