Flames showing! 1983 Johnson J70ELCTE

[JohnnyMat]

Hello all. Looking for some input on an outboard I am attempting to resurrect.
I picked up this one a few years ago with the intent on seeing if I could bring it back to life and I just got done breathing a little fire through her. It's been sitting on a stand outside for at least 4 years.
Rebuilt carbs, changed reeds (CCMS Sports), new coils, plugs, and new fuel pump. I used very rich fuel and sprayed some 2 stoke oil in cylinders and ran the starter a few times to coat walls. It has never been seized (in my possession anyway) and a compression test showed the following.
Cold compression test:
1- 120
2- 112
3- 122

I have a little fuel leaking from the choke solenoid...perhaps bad vacuum diaphragm? When I turn the red knob clockwise it stops leaking. Could not tell exact location of source but it was from the choke unit. What is the deal with that thing btw...how does that work. It has an "air fill" valve on it? Can someone explain that thing to me?

Anyway, it finally fired up, seemed to run "okay" (it ran)...then after about 30 seconds and hitting the throttle (only a little) I had some flames shooting out the bottom of the mid section. The lower unit is off and I have a hose running water directly through the up tube. I shut it off immediately, but wasn't sure if the flames were "normal" or something I need to make adjustments somewhere. It didn't seem to "backfire"...just flames. I didn't let it run to hear anything terribly wrong, but I wanted to get some professional input from you guys. Let me know if you have any questions and thank you in advance for any info you might be able to share.

 

[racerone]

The thingy with the red lever is an ELECTRIC PRIMER VALVE.-------It replaces choke flappers.------It opens when you push the key in WHILE cranking the motor over.----It sprays fuel directly into the carburetor throat.------This fuel bypasses carburetor metering circuits.-----It sprays this fuel because the fuel pump supplies fuel to it while cranking !----Your " air fill valve " is used to directly inject winterizing fluid or engine tuner products !!---A repair kit is available for the electric primer valve

 

[F_R]

Must say I've never duplicated your flames situation, but it's pretty safe to say you probably were dumping a bunch of excess gas into the engine, which went out the exhaust, then caught on fire. The cure is--------don't do that

 

[racerone]

You have a bad compression gauge or issues in the cylinder with 112 PSI.

 

[JohnnyMat]

Must say I've never duplicated your flames situation, but it's pretty safe to say you probably were dumping a bunch of excess gas into the engine, which went out the exhaust, then caught on fire. The cure is--------don't do that

I was just running it normal through the fuel system/carbs. I didn't dump any gas into the carbs or anything. After it started, I let it run for a minute, it smoked a bit, I burped the throttle a little, had some flammage. Turned it off immediately afterwards.

 

[F_R]

In your original post, you talked about the primer solenoid and red lever. If you opened the red lever, you dumped extra gas into the intake. I wasn't there so don't know. Besides, you were running it with the lower unit off. Who knows what goes on in there under that situation? Or even with the lower unit on, for that matter. There is always fire coming out the exhaust ports, it just normally extinguishes itself

That's all I have to offer.

 

[JohnnyMat]

You have a bad compression gauge or issues in the cylinder with 112 PSI.

Compression gauge is brand new (not to say new things can't be bad). Are those comp numbers so abnormal that it would have you thinking a gauge issue? If so, what kind of numbers should I be seeing on the cold comp test?
I wasn't too upset with them, but only because it was a cold test and the lowest number came in within the "10% rule".
The gauge was hooked up to the spark plug holes via threading in the hose...not using the rubber grommet tip. Was sure to check each cylinder a few times...all readings close...+/-2 psi. I disconnected the gauge after each attempt and moved to next cylinder...(not just releasing the pressure and retrying).
I will try another cold compression test again today to see if I get diff readings.

I checked the plugs...still clean...top plug was the dirtiest of the 3.
I'll run out and pick up a camera to try bore scoping it, to see if I can see anything abnormal in the cylinders. Otherwise, maybe a stuck ring from sitting for so long? Should I be running Seafoam through it at this point?

I visually inspected the lower cylinder walls when I had the intake off. Everything appeared to look really clean. I also inspected the connecting rods, and tried to test the bearings/journals for any play...best I could anyway. All appeared to be nice and tight. I realize that's a very limited inspection, but, nothing jumped out at me.

I did have fuel leaking from the primer unit too. Is it possible some fuel made it's way down into the exhaust housing from the top and ignited? Not sure if that's possible or not. It turns out the red service valve on the primer unit has a crack in it, and the gasket was varnished pretty good. Hence the leak. I just ordered that new kit.

 

[racerone]

Some will argue.----My compression test gauges ( I trust them ) would show 140 PSI on the motor.------Some folks go by the 10% rule.-----I do thing in a different manner.----????---Fuel does not leak from the primer and find its way into the exhaut housing !----Working on your first outboard motor ??

 

[JohnnyMat]

Some will argue.----My compression test gauges ( I trust them ) would show 140 PSI on the motor.------Some folks go by the 10% rule.-----I do thing in a different manner.----????---Fuel does not leak from the primer and find its way into the exhaut housing !----Working on your first outboard motor ??

I will try the comp test again.

This is the first "larger" outboard I have really worked on. I've done standard maintenance on my '82 60hp (and a cable harness swap) and a '81 9.9hp, but this is a little more involved. First time trying to actually bring one back from the dead.

Regarding the primer leaking...I wasn't sure if the fuel could somehow work its way down there and ignite because the lower unit is off. Just spit balling.

 

[JohnnyMat]

Some will argue.----My compression test gauges ( I trust them ) would show 140 PSI on the motor.------Some folks go by the 10% rule.-----I do thing in a different manner.----????---Fuel does not leak from the primer and find its way into the exhaut housing !----Working on your first outboard motor ??

Just retested: Cold Comp.

1 - 140-145
2 - 130-132
3 - 132-135

I was using an extension tip the last time I took the comp readings. These measurements were directly off the main line from the testing hose this time. Other than running the engine for a few minutes that tip extension is the only difference between the two days I did comp tests. .

 

[oldboat1]

Screw-in style tester, with a compression release button. Crank the engine with plugs out until the needle stops increasing, and record result. Throttle position has no bearing with your motor.

Flames! Cool. Haven't run into that, but never run them with the l.u. removed (although sometimes flush that way without motor running). You might run some Pine Sol up into the leg, then power wash or at least hose it out (could run it up the water tube and flush the water passages that way too). Won't stop the flame out, but should stop it from getting any worse. The inside of the leg collects a bunch of nasty exhaust stuff.

 

[JohnnyMat]

Screw-in style tester, with a compression release button. Crank the engine with plugs out until the needle stops increasing, and record result. Throttle position has no bearing with your motor.

Flames! Cool. Haven't run into that, but never run them with the l.u. removed (although sometimes flush that way without motor running). You might run some Pine Sol up into the leg, then power wash or at least hose it out (could run it up the water tube and flush the water passages that way too). Won't stop the flame out, but should stop it from getting any worse. The inside of the leg collects a bunch of nasty exhaust stuff.

It didn't shoot flames until I burped the throttle a little. As someone else mentioned above, may have been due to dumping too much fuel through the primer solenoid. Turns out its cracked too. Have a new one on the way.

Redid the compression test without using an extender tip. New readings are: (Tested multiple times) Cylinder 1 jumps right up. The other two take just a little longer to get up to max pressure.

1 - 140-145
2 - 130-132
3 - 132-135

 

[oldboat1]

Repeat tests under the same conditions on a cylinder should give you the same reading if you are testing correctly.

 

[JohnnyMat]

Repeat tests under the same conditions on a cylinder should give you the same reading if you are testing correctly.

Well, I've tested multiple times today...all the same. I'm trying to find out if these 130 readings are okay or if its something I may need to address before I start really running this engine. I will try to do a seafoam treatment to see if it makes any difference.

 

[oldboat1]

no ranges. discreet number for each.

If 140-132-135, you are probably OK imo. Some running may even things out, and a new head gasket wouldn't hurt (resurface the mating surfaces). I would stay away from additives for now. If mixing yourself run 50:1 with a good TCW-!!! outboard oil, and fresh gas. (just mix a gallon at a time for testing).

 

[boobie]

I wouldn't worry too much about those compression numbers. You may want to find some OMC Engine Tuner and run through it.

 

[webbd]

When you burped the throttle, did you burp it using the gear selector or just at the carburetors? These engines have a mechanical ignition advance operated by the throttle/gear selector mechanism on the side of the engine. If you just burp the throttle at the carbs, it doesn't advance. If yours is running too retarded, it might not have burned completely before the exhaust port was uncovered.

Second question: Are all the coil primary and secondary wires connected to the right coil packs and cylinders? A late firing due to wrong spark timing could cause flames down the lower leg.

Third question: How old are your coils? They go bad eventually and you can have all kinds of wonky problems with your engine when that happens.

Fourth question: How much blue/black smoke was coming out when it ran? Might you have been in a flooded situation and watched excess fuel burn off in the drive leg?

--DW

 

[racerone]

How much for this motor ?----I have always wanted a " belch fire special " to add to my collection.

 

[JohnnyMat]

When you burped the throttle, did you burp it using the gear selector or just at the carburetors? These engines have a mechanical ignition advance operated by the throttle/gear selector mechanism on the side of the engine. If you just burp the throttle at the carbs, it doesn't advance. If yours is running too retarded, it might not have burned completely before the exhaust port was uncovered.

Second question: Are all the coil primary and secondary wires connected to the right coil packs and cylinders? A late firing due to wrong spark timing could cause flames down the lower leg.

Third question: How old are your coils? They go bad eventually and you can have all kinds of wonky problems with your engine when that happens.

Fourth question: How much blue/black smoke was coming out when it ran? Might you have been in a flooded situation and watched excess fuel burn off in the drive leg?

--DW

I just hit the carb linkage a few times to rev it up.

All wires are connected properly.

3 brand new coils, wires, plugs. Good spark at each plug.

Don't recall "blue/black" smoke at all. Just heavier white'ish smoke then the flames. It was at dusk so I didn't get a great view of the actual smoke color.

I think it was a flooded situation. The exhaust housing was dripping with black "oily" substance. Probably unburned fuel. I am going to clean that housing out....its pretty funky up in there!
Just got the new primer rebuild kit. Throwing that on tomorrow along with the carbs, and will try firing it up again. I did go out and purchase a gallon can of that Seafoam stuff. I wanted to wash down the piston heads because they are all black, but a previous poster advised against running additives just yet. I'll try getting her running first, then blow some of that stuff through it to see if I can clean her out. We'll see what happens. I'll take a video of the show! lol

 

[ct1762@gmail.com]

just make sure when rebuilding the primer solenoid valve you screw down the top piece with the red valve away from the main body, so that when you screw it in and turn the lever it doesn't shift.