Suzuki DT30c won't start, but runs when I get it doing

[rymored]

I have a Suzuki DT30C from 1994 that's been running fine for years. A couple of weeks ago I had some problems with the engine on a boat trip, and I've been struggeling with finding the answer ever since.

The last time I had the boat out the engine was hard to start, but I got it going after about 10 minutes. Then it ran just fine for about 20 minutes, before suddenly the engine power dropped to about 1/3. After cleaning out the fuel filter and checking a couple of other common issues, cable connection, etc., I got it going at about 2/3 engine power so that I could get myself back to the marina. The fuel filter had some water and dirt in it, so I'm thinking this could be a part of the problem. Could this explain the problems I'm experiencing now ? I assume that when I get the engine going how, it does not run at full capacity, but since the engine is on land it's kinda hard to tell.

I've tried replacing the spark plugs, cleaning out the fuel filter and controlled that fuel reaches the carborators when the engine turns over (I disconnected the fuel line at the top cylinder, cranked the engine over a couple of times and saw that fuel came pumping out). What to do next? Any thoughs and ideas would be greatly appreciated!

PS. I should also mention that I did not do any "fall-maintenance" before putting it away last year, and I did not do any "spring-maintenance" before taking the engine out for the first time this year.

 

[99yam40]

Re: Suzuki DT30c won't start, but runs when I get it doing

Sounds like you need to drain and clean the whole fuel system.
Tank, lines, bulb, pump, and carbs.
Water and trash is not good for a motor

 

[mike__b]

Re: Suzuki DT30c won't start, but runs when I get it doing

Yeah, sounds like you have bad fuel to me. Suzuki has a fuel water separator you can buy, but the easiest thing to do is just try new gas. Also, you may try some of the various recommended fuel treatments for outboards / engines.

 

[rymored]

Re: Suzuki DT30c won't start, but runs when I get it doing

Any tips or links to online guides related to cleaning the whole fuel system ? How to drain and clean tank, lines and bulb ? How to check and clean the pump ? And what about the carbs ? Could some of the "various recommended fuel treatments" be a decent substitute to pulling everything apart or is this the only way to get it good enough ?

Thanks so far!

 

[mike__b]

Re: Suzuki DT30c won't start, but runs when I get it doing

If it hasn't sat long, I'd just dump the gas (use it in your lawn mower) and get new gas. Run the new gas for a while. Any small amounts of moisture in the lines, etc will flush out. Just let it run for a while to where the system is flushed. That's what I would do anyway. I've done this with old gas on my boat for a tank that sat outside for a while and I was concerned it had water in it.

Suzuki's recommended "fuel conditioner and water remover" is part number 99950-06010.
I use Sea Foam, available at Walmart, etc. Some people swear by Sea Foam to keep motors running...

 

[99yam40]

Re: Suzuki DT30c won't start, but runs when I get it doing

There is a good chance of messing up a motor is it is running lean on one or more cylinders by running it while shoving additives in the fuel to see if will get better

 

[mike__b]

Re: Suzuki DT30c won't start, but runs when I get it doing

the easiest thing to do is just try new gas.

Do that first, before using additives. I'd use a low octane since it will ignite easier, but it won't run as clean. Don't try using anything high octane, 86 or 87 is actually easier to get most motors running. But from what I hear, most manufacturers are "recommending" always using their additive in every tank of gas.

 

[99yam40]

Re: Suzuki DT30c won't start, but runs when I get it doing

The higher the octane the slower it burns the lower it is the faster. Not really easier to ignite.
Fuel additives are good for preventing fuel problems, but will not fix problems that have already happened.

Drain/pump out all you can and then take things apart to clean them up and flush them out or replace.