Spark and gas but wont run, 225HP

[Philn]

I have a 225 HP Johnson 1995 looper.
I get spark and gas but will not fire.
Replaced the power pack since it was the original, but still no go.

Where next?
Any suggestions would be appreciated.

 

[Reggie08]

Re: Spark and gas but wont run, 225HP

Have you checked the kill switch wire? Should be black and yellow

 

[tashasdaddy]

Re: Spark and gas but wont run, 225HP

if it were the kill circuit, he would not be getting spark. what has recently been done to the motor? have you checked compression?

 

[Reggie08]

Re: Spark and gas but wont run, 225HP

if it were the kill circuit, he would not be getting spark.

Good point :redface:

 

[JB]

Re: Spark and gas but wont run, 225HP

Go to Engine FAQs and do the troubleshooting in "Outboard won't start".

 

[Philn]

Re: Spark and gas but wont run, 225HP

Checked compression on only two top cylinders @ 60. Low, but that is my recollection of what compression was after rebuild several years ago.

Nothing done recently to the motor. Just wouldn't start after running fine 3-4 weeks earlier.

 

[Hoss 350]

Re: Spark and gas but wont run, 225HP

Check all cylinders. They should be close. But at 60psi, that is really quite low. I wonder if you can't get a go because you don't have enough?

That said, once you have gas and spark, there are only a few things that could be messing you up:

1.) Timing (spark not firing at the right time). This is often diagnosable by how hard the starter has to work to turn it over. A timing light is the only real way to know, though.

2.) Mixture. To rich can suppress a spark, and keep you from getting anything. Have to pretty far off, though, and on every cylinder.

3.) Low compression.

I vote for #3. 60 is pretty low.

 

[CharlieB]

Re: Spark and gas but wont run, 225HP

First, verify compression and SPARK on ALL cylinders.

Second, grab onto a timing light and verify that the timing is within the prescribed range, i.e., that the flywheel key has not sheared and shifted the timing.

Inspect your spark plugs.

Once you have established adequate compression, spark and timing, only then can you begin to suspect that the fuel system is at fault.

DO NOT ASSUME that anything is right, test and re-test each cylinder, check the battery to ensure adequate cranking speed. Slow cranking will not produce a hot spark and make an engine very hard to start. Check battery cable connections, both ends, both cables.

 

[JB]

Re: Spark and gas but wont run, 225HP

**Sigh.**

Do the troubleshooting, Phil. That will tell you what is wrong.

 

[Philn]

Re: Spark and gas but wont run, 225HP

Did compression test on all cylinders. 60 psi, but I think that is what it has been for a long time.

Motor turns smoothly, but I suppose it still could be out of time.

Plugs were wet with gas, put in dry ones, but still wouldn't fire so dont think it is too much fuel.

Timer base ohm meter test shows no readings where shop manual indicates there should be.
Can bad timer base be the cause?

 

[clanton]

Re: Spark and gas but wont run, 225HP

How did you check the spark?

 

[JB]

Re: Spark and gas but wont run, 225HP

What did you find when you did the troubleshooting, Phil?

 

[LubeDude]

Re: Spark and gas but wont run, 225HP

Not sure if this is your problem, but you have to have a "PIG" of a battery to start a looper, a 1000 CCA Battery is called for!

If your Comp tester is accurate it will not start with those #'s! Because you have even #'s I would say that you need a new comp tester. 100-110#'s is about normal!

 

[alwood0422]

Re: Spark and gas but wont run, 225HP

I would imagine that even with Low Compression it would run, or at least try to run and have degradation of power. I have a 200 HP 1987, My compression is slightly low with 95 in each cylinder, so you are definitely low. keep going back to the basics of spark and fuel. If you need to spray fuel in the carbs to make sure it is getting some, or spray fuel in the spark plug hole. Check and recheck the spark.

 

[Philn]

Re: Spark and gas but wont run, 225HP

I tested spark on all cylinders by pulling plug wire from plug, install a loose plug in the wire, hold side of plug to ground, crank engine and watch spark arc on the plug.

Rechecked the timer base ohmmeter reading and verified no readings at all.
Don't know if this points to timer base as problem.

Want to do a TDC pointer verification, but shop manual doesn't address it, CDI trouble shooting document says need to use a piston stop tool or dial indicator to accomplish this. I am looking for directions and a way a accomplish this test without buying the special tools.


Phil