1982 suzuki dt9.9 starting problems

[japratt67]

I have an old 9.9 I am trying to fix. The guy I got it from said he thought it had a bad CDI unit. I thought the problem was either spark or fuel related. I poured some mixed fuel in a spray bottle and sprayed a squirt in each cylinder, replaced the plug, and it started every time and ran a few seconds before it burned the fuel up. I think I eliminated a spark problem since the motor started with fuel sprayed in the cylinder. I took the carburetor apart and cleaned it and blew it out with an air compressor, but it still will not start. I even took the fuel pump apart to check the diaphragm and it looks good too. It looks like the fuel is getting to the carburetor, but is not making it through to the cylinder. I am thinking that it must be fuel related, but do not know where to go from here. Any help will be appreciated.

[Solarman]

Check for vacuum at carb, hold hand over throat (if possible), pull start several times. Is there good vacuum? Did any gas & oil get in throat of carb, on hand? If gas in throat, do plugs get wet?
Have you checked compression?

Post back when able, let us know.

[japratt67]

Thanks for the info. I held my hand against the throat and could not feel much vacuum and I do not see any gas in the carburetor throat. I was looking at it and trying to figure out how the gas gets from the carburetor to the cylinders to diagnose my problem. I know how a car engine works, but I am new to outboards. The plugs look wet, but that may be left over from the gas I sprayed in there. It feels like it has good compression when I turn the motor over, but I have not checked it with a tester. The motor is really clean and does not look like it has been used much. I will rent a compression tester at autozone and see what the readings are. It may be this weekend before I have a chance to test it, but I will post what I find. Thanks again.

[Solarman]

For 2 stroke motors, it operates on compression spark and fuel, to get the fuel to the cylinders a vacuum is created in the cylinder(s) pulling fuel mix into combustion chamber. If not getting good compression, may not be getting good vacuum through carb.
Sometimes old gaskets and seals cause leaks, preventing good suction for compression. Other times it is related to rings seating good. But if had it running, I might check spark and vacuum type leaks.

Good luck.post back if find anything.

[japratt67]

I tested my compression with a compression tester and I am getting 115 on each cylinder. I put my hand over the carburetor and I did not feel any suction. I got gas on my hand and it is running out of the top of the carburetor so it is coming out of the carburetor but is not being sucked backed into the engine.

[Solarman]

When hand is over carb throat, did you get back and forth pressure? If pressure, and vacuum at throat of carb (like in and out motion) the reed valves may be the problem. If not any pressure pushing out, but real weak vacuum, that might be leaking seals at top, or bottom of crank shaft, or could be bad gasket seal, at base of carb, or the intake the carb is mounted to.

If you have enough suction to pull gas into carb (and get on hand when covering throat of carb) seems like should be enough to get into cylinders? Dry plugs with compressed air, then try to start normally. Check plugs to see if wet? If dry, reinstall them, and put hand over carb throat, then remove hand and try to start.check plugs again, wet?

Post back, let us know, when able.

[japratt67]

I got my motor to start. I took out the spark plugs again and squirted an eyedropper full of gas into the head and put the spark plugs back in and started it up and it burned up the squirt of gas. Next I squirted gas into the carburetor throat and it started up. I hooked up my gas tank to the motor and it still would not start so I squirted a couple of squirts into the carburetor and started it up a couple of times and then it started and ran from the gas tank. I put some sea foam in the gas to see if it would clean up any gunk. Now it will idle, but only with it choked almost all the way. As long as I leave it choked almost all the way, it will idle. If I let the choke off, it dies. I am not letting it run long because I have one of those suction cups things hooked up to my water hose and it is blowing water out of the propeller, but the motor still seems to be running a little hot. Do you have any idea what may be causing not to run without the choke on? Thanks again for all your help. I have been messing with this motor on and off for almost a year and this it first time it has started from the gas tank.

[japratt67]

I went out and started my motor again and this time it ran after a minute or so without the choke on. It was hard to get started up at first. I had to squirt a little fuel in the carburetor throat but once I got it started and it ran a minute, it would idle without the choke on it would start right up with the choke off. I will let it cool off for a while and try it again later. It seems like the more I run it, the better it runs. I may need to take it out to the lake and try to blow the cobwebs out of it.

[Solarman]

It's possible you didn't get the idle pas-sages cleaned enough, but it appears it's cleaning itself. The sea foam should help as it runs.

Over heating is not good. Has motor been run dry at all? Do you have a good stream of water from tell-tale? You may need a new water pump kit installed. If turned over dry to many times the impeller could be shot, it has to have water to lubricate it. If dry, it won't last more than a few seconds, before it fragments.

If overheating, that problem needs to be fixed. Before taking to blow cob webs out.
If you have a large bucket, container, or small trash can, that should work. It needs to be higher than the water pump, can block container up with wood to raise it up, but water level should be a few inches above pump.
When running, the water coming out of the tell-tale should not be too hot to hold hand in it. If it gets to hot, need to check thermostat and water pump system.
If you have blockages, in the water pas-sages, you can try running a corrosion flush, or vinegar for a couple of hours (in ten to twenty minute stages, letting same solution in bucket cool down between runnings). Providing water pump, thermostat, are ok, and any blockages are not set up like concrete (may mean manually scraping clean), your motor should start cooling down more, and then the lake run.

Good luck, let us know how it's going.

[japratt67]

Do you have any suggestions to solve the hard starting problem? I went out again last night and cranked and cranked on it and it would not start. I did not have enough mixed fuel in my second gas can to get any with an eyedropper to squirt in the carb so I put it away for the night. After the engine is started and run a minute, it will start up with one pull. After you let it sit for an hour or two and the engine cools down, it will not start without fuel squirted into the carb throat.

[Solarman]

You may still have blockages in the idle pas-sages that didn't get cleaned out good enough, you may have to take carb back apart, and let it soak in carb cleaner for a couple hours before blowing idle pas-sages out with compressed air again. But need to fix the overheating problem too. It won't do any good to get it running well, if it overheats and damages the rings, or pistons.

Good luck. Keep us posted on how it's going.

[japratt67]

I am looking at the diagram for my carburetor, it has a pilot jet, and air jet, and a main jet. Should I remove the jets before I soak the carburetor? I soaked the carburetor and blew out every passage and hole that I could find with compressed air before but I was afraid to remove the jets. The next time I work on it, I also plan to replace the water pump impeller and try to blow compressed air and water through the cooling system.

[Solarman]

Yes, you have to remove the jets to clean properly. If it is an adjustable screw jet (idle mixture screw) slowly close (counting each turn) till lightly seated, and write that down. You will want to reinstall it to what the manual suggests, but it's important to know what it was set at. Then re-clean/ soak carb again, blow pas-sages again, them re-assemble.

You still have to fix overheating problem before running.

Good luck.

[japratt67]

1982 suzuki dt 9.9

I bought another old boat and motor and have been working on it, so now I am getting back to the suzuki. I put a new impeller in and it solved my overheating problem. I took the suzuki out to the lake today. It starts on the third pull with the choke on and runs great with the choke on. After it warmed up, I tried to wean it off the choke and slowly pushed it in. It will idle and troll with the choke in, but when you give it throttle it dies. It will rev up in neutral with the choke in, but when I put in gear, it dies. If I pull the choke out, it revs up and runs great. I ran it for about 2 hours on the lake to see if I could get to run with the choke in. I thought it was going to take off a few times, but it would bog down and die. It took a little more throttle before dying, but nothing much over fast trolling. I assumed the problem was a clog in the carburetor. I brought it home and tore my carburetor down, took out all the jets and did not see any blockages. I blew air threw all the passages and it seemed clear. I have not put the carburetor back together. I may soak it again. I know my fuel economy will suffer, but will it damage my motor if I run it with the choke out?

[Solarman]

Actually if it runs better with the choke out, then your economy should be closer to normal, and it should not add harm to the motor. If your motor is running poorly/flooding when choke is out, your economy is less, and running poorly does more harm than good.

From what you have told me, it sounds like your problem is a fuel/air blockage in the jets, or in the pas-sages. So if you removed, the needle valve & seat (possible trash behind the seat), plus all the jets, then letting it soak well. then a couple hours later, blow out the air and fuel pas-sages, I feel pretty sure your problem should go away.

Add some sea foam, or other good fuel additive to each tank of fuel, run your motor at least every month or two, just to change the old fuel in the carb, and re-lube the internals, and I think you'll be fine for a long time.

Good luck.