Starflite 135 HP Troubleshooting Help

[brandonkbrock]

I just recently bought a 1981 Ebbtide Dyna Trak with a Evinrude Starflite 135 HP engine that's not running very well. Here's what I've done so far and what has happened.
1. It took a while to crank and then would shut off when throttled up in a barrel of water (this was at the guy's house I bought it from... he lived an hour from the nearest water, so unfortunately I couldn't take it out to test in water. It was a good deal, so I bought it anyway).
2. I put fresh gas and oil mix in the tank
3. I took it to the lake and it would not start at all. It would turn over, fire for a second, and then peter out.
4. I made sure it was getting fuel through the line
5. I put a new battery on it because the old one wouldn't hold a charge
6. I put 4 new spark plugs on it (the motor recommends Champion UL77V but the auto stores in my area were out so I used NGK comps).
7. Took carb off and cleaned it
8. It fired up pretty easily w/ water hose and muffs when I put the carb back on, ran for a while, and then shut off. There's a little smoke coming out of the two holes on back of motor (where normally water would spit out). The water that is coming out of the slots in the foot is hot.

Any ideas? The guy I bought it from said he had changed the water pump a few months ago, but I don't trust him. Could it be overheating? Any other suggestions? Do these engines have fuel pumps?

Thanks!

 

[emdsapmgr]

Re: Starflite 135 HP Troubleshooting Help

I'd remove the current plugs and locate the correct ones that are recommended. That engine does not have a telltale. You have to check a couple of things to see if it is cooling normally. 1. A laser temp gun should show cyl head temps of around 120 to 140 degrees when running on the garden hose. Any readings much over 155 would be of concern. An overheat horn should go off at 212 degrees. You can rent a laser gun at most auto parts stores. 2. Start the engine when it is cold. Hold the palm of your hand back by the two exhaust relief ports at the top of the midsection. After 45 seconds or so, water droplets should start to form on your palm. This mist indicates that the thermostat has opened- a good sign. If you don't see the droplets, be concerned. Possible the fuel pump is weak. Once it is running, constantly prime the fuel hose bulb. This will force fuel around the pump-into the carbs. If it only runs when you prime the hose bulb, the pump may be weak. The original rubber fuel components on that engine are not made to handle today's ethanol fuels. The ethanol will break down the rubber and bits will transfer through the carbs-could lodge in the jets. You may want to consider changing all the fuel hoses and perhaps the fuel pump (it has a rubber bladder). It is normal to see a little blue smoke out of the exhaust relief ports-but you don't want to see a lot of white smoke-could be an indication of an overheat.

 

[brandonkbrock]

Re: Starflite 135 HP Troubleshooting Help

Thanks! I'll get the plugs ordered and try your suggestions.

 

[brandonkbrock]

Re: Starflite 135 HP Troubleshooting Help

I've ordered the correct plugs and a laser temp gun (figure it'll come in handy with my deep fryer and smoker also). It didn't run any differently when I pumped the primer bulb and the rubber in the fuel pump looks good (appears to have been replaced not too long ago). Took the carbs off and cleaned them again, this time letting them soak longer in Berryman's Chem Dip and then spraying with carb cleaner and compressed air. The hoses appear to be in good shape, but I will probably replace them to be safe.

Here is a video of how the boat typically runs... it's usually difficult to crank (several turnovers, sometimes won't crank at all) and then it will often just suddenly stop on its own like in the video. It has ran steadily until I turned it off a few times, but these instances are rare! I do have a video of it running steadily without shutting off if anyone thinks that would be helpful.

 

[hidef]

Re: Starflite 135 HP Troubleshooting Help

Check all of your wiring to eliminate any chances that it might be an electrical issue. Start by checking all of your wiring

http://maxrules.com/graphics/omc/wiring/V4_1973.jpg
http://maxrules.com/fixomcwiringcodes.html

Also use the CDI troubleshooting guide in my sig. The manual calls for UL-77 plugs use the QL-77 set the gap at .030. The UL plugs have a nasty habit of fouling if you idle to long.

 

[brandonkbrock]

Re: Starflite 135 HP Troubleshooting Help

Okay, so I have the QL77s in there now. All are getting spark. Compression tests were around 150 psi on first turnover. It settled around 180 on the 3rd tunover. This seems pretty high... All cylinders were within 5 PSI of each other. The motor is running well now on the muffs with the new plugs and the cleaned carb, but when I put the foot in a barrel of water, it will not crank at all. It's also not putting out drops of water from the two nickle-sized holes in the foot anymore. Any ideas or suggestions? Someone suggested it having too much back pressure but I have no idea how to check for that or go about fixing it.

 

[emdsapmgr]

Re: Starflite 135 HP Troubleshooting Help

You may want to recheck your compression with another gauge. I doubt that engine has much over 135 compression-which is really strong for that year. Putting the lower unit in a water tank should still crank over just like when it is out of the water. It's the running of the engine (rpm's) which is affected by the depth of the water. The engine started well and seems to run fine in the video. Halfway through the video, the engine started to lean sneeze. (occasional cough, or sputter.) This is probably due to a fuel restriction in the idle passages of the carbs. Also possibly why it shuts off abruptly. You may want to clean the small, dedicated idle passages in the upper carb body again.

 

[brandonkbrock]

Re: Starflite 135 HP Troubleshooting Help

This motor is driving me crazy. I bought a different compression gauge and it tested fairly even and high on all cylinders (ranged from 145 to 160). Took carbs off and cleaned again, this time as thoroughly as I possibly could. It was still running rough. I finally broke down and took it to a mechanic to diagnose. He said it was either the reed valves or that air was coming in through the gel coating between the two engine halves. I took the carbs back off and looked at the reed valves, and they look fine to me. The motor won't crank unless I spray gas into the carbs. I took it on the water today and it ran REALLY slow. Still lean sneezing. Also, there's water in the foot oil, so I got screwed on this purchase .

 

[emdsapmgr]

Re: Starflite 135 HP Troubleshooting Help

I need to ask-does the choke/solenoid work on this engine? A slow running engine would seem that it is not running on all cyls. Run the engine on the trailer on the garden hose. When running, pull one of the spark plug wires off a plug with a set of insulated pliers. The engine rpms should drop noticeably. Put that wire back on and check the next plugwire. If you pull one plugwire off and you get no rpm drop, that is a problem. Remember to warm the engine up fully. Weak ignition components tend to run fine when the engine is cold.