Starting A Dead Outboard

pftreadman · 08-10-2004, 12:05 PM

I recently aquired a 6hp evinrude 2 cycle 70ish outboard motor. I cannot get it to start, yesterday I got a little exhaust but it would not start. It does not catch at all. I replaced the spark plugs and tried some starter spray.The person I bought it from said that it runs well, but im not too sure anymore. I would really appreciate some advice. Thanks.

Dave R · 08-10-2004, 12:22 PM

you need three things to run, fuel and air mixture, spark and compression. You don't have one of them. Easiest to test is compression. Does the engine resist being pulled over? If so, you probably have compression. Next easiest is spark. Pull a spark plug out, re-attach it to the spark plug lead, hold it tightly against the engine and have someone pull the starter rope. You should see a nice blue spark. Check the other cylinder the same way. I'm betting both will be OK which leaves fuel and air. Odds are extremely good you are getting enough air so fuel starvation or flooding would be the likely causes. After trying to start it for awhile, pull a spark plug. If it's wet, fuel starvation is not any issue. If it's dry, you need to sort out the fuel delivery. There is a possibility of flooding if the plug is wet and that's generally caused by operator error.

My money is on a dry plug with good spark and good compression. Check all fuel connections, make sure the fuel is fresh and the oil is properly mixed to the right ratio. If that all checks out, verify the primer bulb is doing it's job of getting fuel up to the carb. If that checks out, clean and/or rebuild the carb. Rebuild kits for that carb are readily available (they cover a huge span of years) and are quite cheap. The process of rebuilding a carb is simple and does not require special tools, but does require compressed air and carb cleaning solvent. Said solvent isn't very pleasant to have in your eyes so be careful when blowing it out with compressed air.

Just Sold · 08-10-2004, 07:30 PM

You said this is a 70ish motor. Depending on the manufacturer it could have a set of points and condenser under the starter pully. Remember outboards and I/O's did not have to meet EPA emmission standards untill recently so old technology such as points were still used. The points could be dirty and need at a minimum a little cleaning.

My 89 5 liter I/O still has points and a condenser.

Good Luck

gtxrider · 08-15-2004, 03:48 PM

I had a problem when I purchased a used outboard. The motor would start and idle but would not run at high speed. It seems that the engine sat with gas in the carbs and gummed up the works. I cleaned the jets and it would run fine for a while and then act up again. I finally bought carb/fuel system cleaner added it to the gas and and ran the boat around in Alton Bay between Sandy Point and the Band Stand. The cleaner did the trick and cleared the fuel system.

If you have spark, I would suspect carb trouble.

madrasahs · 08-15-2004, 06:50 PM

My extended family has five of these '70s 6HP OMC outboards.

They are pretty indestructable engines; however, I've seen it written that one should not use starter fluid to try to start 2-cycles. Reed-valve damage, maybe. (Gum-Out's OK).

Chances are if it was represented as "in running condition", but hasn't been run in a long time, that the fuel is too old or water-contaminated to get it started.

Try a fresh gasoline mixture, then drain the fuel line of its old gas by depressing the round brass valve in the motor-end of the gas line. Squeeze the bulb until the gas runs clear and fresh. (A smell of "varnish" in the fuel means it's really old gas).

Last year's gas mixture in the fuel line always makes for difficult start-ups in the spring.

If you need parts, the serial number plate will express the year of manufacture. Bombardier acquired OMC, but advised me a couple of years ago that parts were no longer being stocked for these engines.

(So I bought a "running spare" for $75. All our engines continue to run strong and have yet to borrow a single part from the spare).

08-10-2004, 12:05 PM	#1
pftreadman Junior Member Join Date: Jun 2004 Posts: 2 Thanks: 1 Thanked 0 Times in 0 Posts	Starting A Dead Outboard I recently aquired a 6hp evinrude 2 cycle 70ish outboard motor. I cannot get it to start, yesterday I got a little exhaust but it would not start. It does not catch at all. I replaced the spark plugs and tried some starter spray.The person I bought it from said that it runs well, but im not too sure anymore. I would really appreciate some advice. Thanks.

08-10-2004, 07:30 PM	#3
Just Sold Senior Member Join Date: Apr 2004 Location: Suncook, NH, but at The Lake at Heart Posts: 2,612 Thanks: 1,082 Thanked 433 Times in 209 Posts	Hard Starting Problems You said this is a 70ish motor. Depending on the manufacturer it could have a set of points and condenser under the starter pully. Remember outboards and I/O's did not have to meet EPA emmission standards untill recently so old technology such as points were still used. The points could be dirty and need at a minimum a little cleaning. My 89 5 liter I/O still has points and a condenser. Good Luck __________________ Just Sold At the lake the stress of daily life just melts away. Pro Re Nata

08-10-2004, 12:22 PM	#2
Dave R Senior Member Join Date: Jul 2004 Posts: 2,974 Thanks: 246 Thanked 736 Times in 438 Posts	you need three things to run, fuel and air mixture, spark and compression. You don't have one of them. Easiest to test is compression. Does the engine resist being pulled over? If so, you probably have compression. Next easiest is spark. Pull a spark plug out, re-attach it to the spark plug lead, hold it tightly against the engine and have someone pull the starter rope. You should see a nice blue spark. Check the other cylinder the same way. I'm betting both will be OK which leaves fuel and air. Odds are extremely good you are getting enough air so fuel starvation or flooding would be the likely causes. After trying to start it for awhile, pull a spark plug. If it's wet, fuel starvation is not any issue. If it's dry, you need to sort out the fuel delivery. There is a possibility of flooding if the plug is wet and that's generally caused by operator error. My money is on a dry plug with good spark and good compression. Check all fuel connections, make sure the fuel is fresh and the oil is properly mixed to the right ratio. If that all checks out, verify the primer bulb is doing it's job of getting fuel up to the carb. If that checks out, clean and/or rebuild the carb. Rebuild kits for that carb are readily available (they cover a huge span of years) and are quite cheap. The process of rebuilding a carb is simple and does not require special tools, but does require compressed air and carb cleaning solvent. Said solvent isn't very pleasant to have in your eyes so be careful when blowing it out with compressed air.

08-15-2004, 03:48 PM	#4
gtxrider Senior Member Join Date: Mar 2004 Location: Piscataway, NJ Posts: 1,030 Thanks: 2 Thanked 46 Times in 24 Posts	I had a problem when I purchased a used outboard. The motor would start and idle but would not run at high speed. It seems that the engine sat with gas in the carbs and gummed up the works. I cleaned the jets and it would run fine for a while and then act up again. I finally bought carb/fuel system cleaner added it to the gas and and ran the boat around in Alton Bay between Sandy Point and the Band Stand. The cleaner did the trick and cleared the fuel system. If you have spark, I would suspect carb trouble.

08-15-2004, 06:50 PM	#5
madrasahs Senior Member Join Date: Apr 2004 Posts: 381 Thanks: 0 Thanked 1 Time in 1 Post	My extended family has five of these '70s 6HP OMC outboards. They are pretty indestructable engines; however, I've seen it written that one should not use starter fluid to try to start 2-cycles. Reed-valve damage, maybe. (Gum-Out's OK). Chances are if it was represented as "in running condition", but hasn't been run in a long time, that the fuel is too old or water-contaminated to get it started. Try a fresh gasoline mixture, then drain the fuel line of its old gas by depressing the round brass valve in the motor-end of the gas line. Squeeze the bulb until the gas runs clear and fresh. (A smell of "varnish" in the fuel means it's really old gas). Last year's gas mixture in the fuel line always makes for difficult start-ups in the spring. If you need parts, the serial number plate will express the year of manufacture. Bombardier acquired OMC, but advised me a couple of years ago that parts were no longer being stocked for these engines. (So I bought a "running spare" for $75. All our engines continue to run strong and have yet to borrow a single part from the spare).