J115TLETS shutdown on overheat?

[bart98stang]

Good evening gentlemen,

I have '93 J115TLETS with 13"x19" prop on a 19'4" Sunbird Cuddy Cabin. I'm currently troubleshooting a fuel issue. Thinking my anti-siphon valve was bad I put a straight fitting on the gas tank and I took the boat out for a test run. I was running at WOT at 5400-5500 RPM for about 3-4 minutes and my engine shutdown on its own and it would turn over but it wouldn't restart. Unfortunately I didn't think about putting my hand on the power head to see if it was hot or not but I did notice that water shooting out of the "pee hole" was cool. Water is approximately 60 degrees. After about 45 minutes the motor started right back up and I took it easy back to the dock. I've been trying to find this answer but nothing so far, will the engine shutdown on overheat? The alarm horn does sound when I ground the tan lead but I'm not 100% sure if the temp switches work. Thanks for your time!

 

[Joe Reeves]

Re: J115TLETS shutdown on overheat?

Does the fuel primer bulb have a tendency to be drawn flat when this takes place?

There's a arrow on the fuel primer bulb... is it correctly pointed at the engine?

From what you've had to say, it doesn't sound like the engine is overheating... If the engine go hot enough to seize the engine and bring it to a halt, there is no way the electric starter could crank it over.

 

[bart98stang]

Re: J115TLETS shutdown on overheat?

Joe, thank you very much for your reply. I've read to check the bulb to see if it's flat on many other posts but I never noticed if it was. Not saying it wasn't flat, I just didn't noticed. The arrow on the bulb was pointing in the right direction but the bulb I suspect was pretty old so yesterday I replaced it with a brand new one.

I didn't think the engine overheated and seized, but it was strange that it shutdown at WOT and after trying for 45 minutes it finally started as if the engine had a overheat shutdown circuit and restarted after it cooled down.

After reading post after post about fuel delivery I have replaced the anti-siphon valve, new fuel/water separator, new bulb (pointing in the right direction), new in-line filter, new quick disconnect fitting and all fuel lines in between except for between the anti-siphon valve and splash well bulkhead. I haven't checked to see if the vent was clogged which I will do tomorrow. I will post my results.

Lastly, why would the water out of the "pee" hole still be cool even though for certain the engine was up to temp?

 

[boobie]

Re: J115TLETS shutdown on overheat?

Get an open air gap spark tester, set it to 7/16 " air gap and check your spark when it quits. It could be an ign prob.

 

[Joe Reeves]

Re: J115TLETS shutdown on overheat?

Lastly, why would the water out of the "pee" hole still be cool even though for certain the engine was up to temp?

I'm not familiar as to where the water telltale outlet fitting is located on the 1993 115hp model, but usually it is extremely close to the first water passage area that is encountered by the incoming water flow. As such, the telltale water exiting the overflow fitting is simply showing water pressure... water that hasn't been completely thru the entire water flow system of the engine.

 

[emdsapmgr]

Re: J115TLETS shutdown on overheat?

As Boobie said, check your spark. Weak ignition components tend to fail once the engine heats up to normal operating temps. Run the engine again till it quits, then check for spark.

 

[bart98stang]

Re: J115TLETS shutdown on overheat?

Thank you gentlemen for your replies. I thought about spark yesterday afternoon and I did check for spark on all four cylinders and I got a fat blue spark but I'm not sure if I was at 7/16" air gap, I just set the gap and turned it over. I will double check today. Joe, thank you again. I took a look at the water flow diagram in my service manual (actual factory and not a Clymer or Sealoc manual) and it looked like it was at the end of the cooling loop so thats what I assumed where it was.

I know I'm getting a little ahead of myself becuase I have yet to check the timing yet even though I've taken it out on a few occasions so I plan on starting with Joe's WOT timing procedure. I've done it a couple of times on my '91 J200 with successful results.

 

[rothfm]

Re: J115TLETS shutdown on overheat?

Bart,

I dont see where there is a "STOP" circuit for heat that would prevent it from starting. I also have a 1993 J115, with the Sunbird 202 19'er!! I had an overheat issue now solved, but no matter what temp (even with alarm buzzing) it would always at least start.

Do you know actual temps from an IR temp gun? it might be good to pull heads and looking at the water deflectors, head gaskets, then LU impeller? Just so you know thier state, and have peace of mind.

I'd rather rule out a heat issue first, as it can be destructive...Just some thoughts. Going to pm to ask a couple questions of your setup since I have the same.

 

[bart98stang]

Re: J115TLETS shutdown on overheat?

I set the spark tester at 7/16" inch gap and I had a fat, blue loud spark on 3 of the 4 cylinders. The boot off of the other plug wire fell off. It had a lot of salt water corrosion so time to buy new plug wires. Once I get new ones on I will check that last cylinder.

I also did the Joe Reeves WOT timing procedure and the spark advance was 5? low. Manual says 28? BTDC, Joe says to minus 4? of what the engine calls for and I was at 19?. So I set it to 24?.

roth,

I didn't think I overheated the engine but I wanted to make sure so I asked. I'm pretty sure my problem(s) lay with fuel delivery and as stated above the timing was out of whack. Going to order new plug wires and take her underway once again.

 

[Joe Reeves]

Re: J115TLETS shutdown on overheat?

I also did the Joe Reeves WOT timing procedure and the spark advance was 5? low. Manual says 28? BTDC, Joe says to minus 4? of what the engine calls for and I was at 19?. So I set it to 24?.

NOTE: Did you make sure that the "Fast Start" feature was disconnected on that engine before you set the timing via the method I suggested? If not, the timing is set wrong.

 

[bart98stang]

Re: J115TLETS shutdown on overheat?

My engine doesn't have the fast start feature. No white w/black tracer wire coming from temp switch, only a tan wire.

 

[Joe Reeves]

Re: J115TLETS shutdown on overheat?

Strange.... I don't have the schematic or the manual here in front of me but I would think the 1993 115 Johnson incorporated the Fast Start feature.

 

[bart98stang]

Re: J115TLETS shutdown on overheat?

Nope, I just took a look at both thermostats just to make sure I wasn't crazy and I looked at the wiring diagram in my manual and it shows only a tan wire coming from each thermostat. Of course if I ground the tan wire on either side the warning horn sounds. I am by far not a outboard motor mechanic but I've been in the Navy for 17 years as a communications electrician and I don't see a white wire with a black tracer!!

 

[rothfm]

Re: J115TLETS shutdown on overheat?

Yea, I got the same engine...No fast start.