1991 Johnson 28 HP fuel problem, Now alarm goes off

[Mr Bob]

I recently purchased this engine and will not stay running. I can spray starter fluid in the carb and it fires. The fuel pump appears to be new. I want to rebuild the carb but it looks like a nightmare to get the starter off to get to one of the nuts I need to, to remove the carb. Am I over looking something as far as carb removal? Also what direction is the red plastic arrow (shut-off?) supposed to be in. What is that bleeder valve for on top of the shut off. Thanks

 

[tashasdaddy]

Re: 1991 Johnson 28 HP fuel problem

Re: 1991 Johnson 28 HP fuel problem

your thinking is all wrong, starter fluid is the best way to ruin that motor. it is electric start, with a primer, not a choke. the black thing with the bleeder is the primer, the red lever is not a shut off, it is a manual primer, for when the battery is dead, yes the carb need to be thourghly dismantled including the jets soaked and cleaned, then reassembled with a rebuild kit. here's a picture of the correct operating position for the primer. to manual prime the motor you move lever in opposite direction.

 

[wavrider]

Re: 1991 Johnson 28 HP fuel problem

Re: 1991 Johnson 28 HP fuel problem

Hello and welcome to the forum.

You are in the right place for advice with any of your projects. Hundreds of years combined experience here.

Do not use starter fluid on your engine. Starter fluid has no oil lube in it, two strokes require lube.

Use a spray bottle filled with premix, gas and oil same as you would run in your engine. Spray that into the throat of the carb if you are trying to start it.

Sounds lke you have a dirty carb, float needle sticking.

(

You will need new gaskets to rebuild carbs and also mounting gasket to intake.

You can get rebuild kits from this forum sponser. Good prices and not expensive shipping.

The RED handle sounds like a primer solenoid, replaces the old style butterfly choke. Handle should be in the down position when you push your key in it shoots a small amout of gas into your carb. If you raise the RED handle up it will constantly pump gas into your carb when the engine is running. In the up position this is if the choke circuit fails you can raise the RED handle and pump the primer bulb on your fuel line and it shoots gas into the carb to prime it for easier start.

Read in the faq section on starting techniques your engine should be coverd in it.

As far as removing the carb. Sometimes the starter needs removed depending on model of engine. Good time to clean corrosion on contacts also.

Remove the carb paying attention to the linkage rods and connection's.

After you rebuild the carbs you will need to do a link n sync after you install them. Manual again.

Good time to upgrade install new fuel lines also.

If you do not know when the water pump was changed last it is good idea to change it also. Engines do not last long if not cooled properly.

If you do not have an service manual, get one, it will save you hundreds of dollars and it is well worth the money.

( TD we were typing at the same time, hmm out fish me and out type me)

 

[Mr Bob]

Re: 1991 Johnson 28 HP fuel problem

Re: 1991 Johnson 28 HP fuel problem

Thanks gentlemen, the starter fluid was a test to see if electrical was ok, and yes I certainly probably used more of it than I should have. Hopefully I did not screw it up too bad. I won't do that again. Anyone know what the compression should be?? I don't have the operators manual for the motor and never had a motor with that style primer, shows what a rookie I am huh :redface:
Yes the starter definetly had to come off to remove the carb. A little more involved than I would have like just to remove one nut, but oh well.
I will now start to disassemble the carb and see what the inside looks like.

 

[wavrider]

Re: 1991 Johnson 28 HP fuel problem

Re: 1991 Johnson 28 HP fuel problem

Look for 100lbs or better for each cylinder and a variance of no more than 10% difference.

Looking for uniformity between the cylinders on the compression test.

 

[Mr Bob]

Re: 1991 Johnson 28 HP fuel problem, Now alarm goes off

Well after the carb rebuild all is well, runs wonderfully except now after several minutes of running the engine, the hot alarm goes off. It appears to be pumping water fine from the weep hose I will call it, pumps out strong.
Could it be the sensor becoming weak and tripping prematurely? What temp would be normal operating temp for the head with proper water flow?
Help! and thanks in advance.

 

[tashasdaddy]

Re: 1991 Johnson 28 HP fuel problem, Now alarm goes off

140 normal temp. probably tstat, there cheap to replace. while you have it out flush the motor thru the tstat hole.

 

[Mr Bob]

Re: 1991 Johnson 28 HP fuel problem, Now alarm goes off

Thanks..you have given me new hope.
Now at the risk of sounding like a complete idiot since I don't have a service manual yet. Where about on the engine will I find the T'stat, I assume I will need a kit with gaskets??

 

[HighTrim]

Re: 1991 Johnson 28 HP fuel problem, Now alarm goes off

You can see a diagram of your t stat assembly here, #16 in the diagram.

"http://www.crowleymarine.com/brp_parts/diagrams/24832.cfm"

 

[tashasdaddy]

Re: 1991 Johnson 28 HP fuel problem, Now alarm goes off

go here, http://shop2.evinrude.com/ext/index.aspx?s1=0c62234a5731f4b55d35ee424c1ebff3

clik on 1991 then 25 hp then model # then crankcase & cylinders. you need to remove part #46, you need parts # 22,21, 49. you can order right there.

 

[Mr Bob]

Re: 1991 Johnson 28 HP fuel problem, Now alarm goes off

Great diagrams..Thanks.

For clarification I have a 28HP, so I simply followed the steps to get to the diagram I need. I am confused why I need items 22 exhaust gasket and 21 overboard nipple?
The best I can tell from the diagram and never having done this before it looks to me I need items 16 t'stat, 17 t'stat gasket, 49 cylinder hd gasket.
I just don't want to order the wrong parts. Am I viewing the diagram incorrectly?

 

[tashasdaddy]

Re: 1991 Johnson 28 HP fuel problem, Now alarm goes off

100% correct, sorry for the mistake, of the 25, it is not a hard job, you are lucky, the tstats use to be on the bottom there and were a real bear to get to. just watch as it comes apart and goes back together in reverse. good luck.

 

[Silvertip]

Re: 1991 Johnson 28 HP fuel problem, Now alarm goes off

the thermostat may be stuck closed. Remove it and replace it.

 

[Mr Bob]

Re: 1991 Johnson 28 HP fuel problem, Now alarm goes off

Just wanted to follow up on the repair. The problem was the t'stat exactly as
mentioned. I took the boat out the day to run it and the engine ran perfect.
Thanks everyone for your help, it is most appreciated. What a great resouce you folks are.