2015 Suzuki df20 runs rough 5 minutes (after red light turns on), dies

[jpan28]

I have a battery connected to the motor, as it has electric start. However, it also has pull start. So, in my mind it should be able to run without a battery. But seeing that the battery IS connected, can a weak battery cause problems?

[artdf175]

in most cases that I know of, the answer would be yes -- it does matter
all these engine need a good power source
if your battery is 3 or 4 years old would just replace it
or take it and have it load tested

[2014DF25ARS]

If you suspect the battery may be causing the problem, it seems you could simply disconnect it and pull-start the motor for test purposes, making sure that the motor's power cables aren't shorted to anything. I was on a cruise with friends last year and one of them had battery problems during the ride. I gave him my battery to get through the end of the cruise, and just pull-started my motor.

[jpan28]

Moonlighter: Ran the motor with the SDS connected and you may be right about the gradient temperature alarm. Seems to have gone off a lot and seems to coincide with the problems. My question is... does that alarm turn on the red light and cause the engine to go back to an idle? Also, why doesn't this alarm end up as an event code? Thanks.

[Moonlighter]

I am not sure, I am away from home and dont have access to my info.

If the gradient alarm is going off then if I were you, I would do a complete water pump kit replacement, not just the impeller. And also a thermostat replacement, its hardly worth the bother of trying to clean up the old one and test it, simpler to just install a new one.

[Hoosmatroos]

Is this solved yet? The issue with these engines has nothing to do with the fuel delivery or the water pump. It's a 1-2 hour job to resolve this. Underneath the block there is a water passage blocked. This is a common issue with these engines. Disconnect the fuel line on the inside and the cables. Remove the block (8-10 bolts from the underside) and clear the passages. Replace the gasket and put the block back.

The pee hole shows lots of water. Sometimes the line from the fuel cooler will leak because of this. Simple to see and change when you remove the block. Sounds intimidating but all to do is remove some nuts and bolts.

Imho this is a design flaw.

You can check this to hook up the SDS and let the motor run. After only a couple of minutes you see the temp rising and reach the gradient alarm temp. Let it run longer and it will shut down.

[jpan28]

Thanks, Hoosmatroos. I'm desperate enough to give this a shot. Otherwise, I'm looking at possible replacement of thermostat, sensors, impeller... Will let you know.

[Hoosmatroos]

For sure on my side that it's not problem. Tell tail is ok so the impeller must be ok as well. It's a known issue with these engines. Will look for a "how to" if I can find it. But not really hard. For someone who has done this before it's about 1-1,5 hours work.

If you do the job, please take some pictures for future reference. If you have any questions, please let us know.

[jpan28]

This is usually a bit out of my comfort zone, but I have the (electronic) service manual and I'm encouraged that it's fairly straightforward. Not sure I can get to it for a few days, but I'm definitely going for it.

[jpan28]

Hoosmatroos... If you don't mind, can you look at the following picture and identify the bolts I need to remove in order to remove the block for access to the tubes? I've identified in the picture the ones I think that you mean. Thank you in advance.

DFX20Block.jpg

[Hoosmatroos]

Yes, you need to separate the block from the drive shaft housing.

[jpan28]

I'm a bit confused because the service manual might be using different terminology. They refer to "Engine Holder", as it connects to the drive shaft. Is this what you mean? In the diagram below, is this the (possibly clogged) tube you are referring to? A single tube that runs vertically? Thanks
watertube.jpg

[Hoosmatroos]

No, the clogging is a bit higher, just under the engine block. Otherwise it would be possible to poke through the hole from the underside when de leg is removed.

[Hoosmatroos]

Looked again at your picture, the bolts are higher. You can leave the oil pan on the housing. I think they refer to it as the engine holder. So don't forget to drain the oil upfront. You also need new gaskets. When you separate the engine from the holder, look closely to the block inside. Good change that you see more clogging inside. Clean all out as good as possible and mount all back. To prevent this, I heard from a Suzuki friend/dealer is to mount a thermostat as low as possible (he said 42degrees Celcius) and rinse every winter with a citrus acid mix to remove build up chalk.

[jpan28]

Hi. Sorry to prolong the drama, but here goes... The thought of taking off the cylinder block was causing me heartburn as this is way outside my comfort zone. So, I decided to first go ahead and change the thermostat (since I had already purchased the part). When I removed it, I was shocked by the amount of gunk I saw inside the block (see pictures below). This lends credence to Hoosmatroos' theory about clogged up channels inside the block. However, it seems to be mostly salt accumulation (which I can't understand because I have flushed with fresh water after every salt water excursion). And, we're talking about an engine with less than 20 hours! The only thing that occurs to me is for some reason (maybe a bad thermostat), that fresh water never got into the cylinder block to flush it out. So I've decided to first do one or more "flushes" using Salt Away via the flush port and see (via the thermostat hole) if it has an effect on getting rid of the accumulation. Finally, I wanted to float an idea and get your feedback. I know vinegar is great for dissolving corrosion, etc. What would be wrong with filling the cooling system with vinegar and letting it soak for a period of time. I would pour it in through the hole for the thermostat. The hope is that it would help dissolve some of the crud. As I understand it, vinegar is pretty harmless (environmentally, etc.). After a period of time, I would just flush the whole thing with fresh water. Interested in hearing your opinions. Thanks!

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