Hard Starting Engine after Flooding

[hafskip]

Hi all,

I've got problems with a boat diesel (4 cyl, 42 hp) that is hard to start. I attached a sound clip of a cold start. About halfway I stop cranking. The engine then still isn't running by itself. On the second attempt it starts. At the very end of the clip I increase the revs a little. Link: http://www.janharing.nl/motorgeluid.mp3

After the engine has been running - maybe only 30 secs - starting is without any problems. Also it seems to be running alright and able to deliver power. No black/white/blue smoke.

Actually I'm not even sure whether the starter motor is the problem or the main engine. Starter battery is fine and fully charged.

I checked the glow plugs with a test light and they seem alright.

I'm quite certain about the events leading to this condition. About six months ago the engine was flooded with river (fresh) water. I pumped out a great amount of oil/water sludge from the block. Refreshed oil several times and running the engine in between until it wasn't milky anymore. The starter motor is located low on the engine and was also flooded. I didn't notice any starting problems then - also not when cold.

Then it became winter and I left the boat for several months.

When starting the engine the first time in the spring, the starter didn't do anything. One knock with a small hammer on the casing of the starter, something sprung loose and it cranked. Probably something got stuck inside. The knock wasn't necessary anymore the subsequent starts, but the starting is still not good.

Any ideas here after this story and listening the audio clip?

Thanks,
Joost

[SkiprJohn]

It sounds to me like your starter is not spinning your engine fast enough. It also sounds like maybe you have a need to have your injectors tested. It doesn't sound like they are firing equally on start mode.
To be honest this is just a guess and hard to say just by the sound of it but I'd pull the starter and have a shop test it to see how much torque you're getting out of it. It may need a rebuild.

[DeepFrz]

I recommend you pull and overhaul your starter. You could probably do that yourself given some degree of mechanical aptitude.

[sailful]

Sounds to me like you need to give it more throttle right from the beginning. I start mine with lots of throttle and when it fires back it off to about 1200 rpm. It starts much easier this way compared to starting with low throttle and then bringing it up.

[SkiprJohn]

Originally Posted by sailful

Sounds to me like you need to give it more throttle right from the beginning. I start mine with lots of throttle and when it fires back it off to about 1200 rpm. It starts much easier this way compared to starting with low throttle and then bringing it up.

That certainly sounds like the easiest cure.

[hafskip]

More throttle during starting might work, but it is just because this problem occurred after the flooding, that I'm wondering what is wrong. It cannot be normal wear, because it happened so suddenly.

Starter motor test/inspection/overhaul is suggested twice. It very well could be the problem, because it was completely under water and I also had the issue that it needed a tap with the hammer. I go for that one first. Should be able to remove it myself.

But this doesn't sound like damage (compression?) in the main engine? (except injector overhaul - could an injector be damaged by the flooding?)

[Jentine]

It sounds as though there is a very high current draw during the initial start that gradually reduces. I would disassemble the starter and clean it thoroughly. I am sure there is some insulating crud (corrosion) in that is increasing resistance.

[SkiprJohn]

Originally Posted by hafskip

More throttle during starting might work, but it is just because this problem occurred after the flooding, that I'm wondering what is wrong. It cannot be normal wear, because it happened so suddenly.

Starter motor test/inspection/overhaul is suggested twice. It very well could be the problem, because it was completely under water and I also had the issue that it needed a tap with the hammer. I go for that one first. Should be able to remove it myself.

But this doesn't sound like damage (compression?) in the main engine? (except injector overhaul - could an injector be damaged by the flooding?)

That it starts and runs is a very good sign. Injectors with improper spray will prevent them from popping and spraying the right mist at the exact time needed. It sounds by the audio that one or two cylinders are catching but not enough to keep the engine running. It's just a thought. Flooding might not have damaged them at all but any corrosion caused by moisture can have a very negative effect on how they work. It's much cheaper to have them checked than to rebuild or replace a fuel pump and that's why I suggested having them checked first. There's a whole bunch of other things to try to fix this but throttle advance and starter repair would be the easiest. No doubt that your starter needs help.

Let us know how it works out.

[hafskip]

Thanks, will keep you updated.

[NoTies]

Getting a mechanic to check it out will be best. It could simply be a bad ground connection causing voltage drop. If you need to ask the question on here then you need to get expert advice rather than guesses from a sound clip.

[jimbunyard]

Certainly nothing wrong with trying to figure out a problem on your own, most find it commendable. And what if the 'expert' isn't around?

The idea of a sound clip is also good and (at least to me) novel.

Post 7 above is a good idea. I've taken apart many salt water flooded starters, squirted them out with the hose, let them dry in the sun, lubed them up, reassembled them, good as new. The solenoid usually goes out in a year or so though, even if you can take it apart and clean it.

Not mentioned above are the battery cables themselves. If they went under, their lifetimes have most likely been severely compromised. They may look good, but a sure sign of failure or impending failure is increased stiffness relative to other cables. A loose connection could also cause the erratic starting speed.

Seems like there is another problem though. Without knowing your make of engine, one can't say for sure that submersion won't affect the injectors, but the only small marine engine I know of that uses injectors that can be directly affected by short term water immersion are Detroit Diesels with unit injectors, and that didn't sound like a Detroit to me. So without having more specifics, but hearing the engine finally catch and run (though it did sound like a cylinder was missing, the clip wasn't long enough to tell), and assuming that the engine was only under water for a short time I would say no, the injectors are probably fine.

It does sound like the engine is starving for fuel, so in keeping with the philosophy of simplest things first, I would check fuel tank vent, fuel filters, and pickup tube before moving on to more complicated (read expensive) issues.

[hafskip]

I like doing things myself. That way I learn something and with boats I often found that knowledge very useful in the most unexpected situations.

However with something as complex as an engine, I certainly see a point after which it becomes risky and/or very time consuming to do it yourself.

I also think that the starter/circuit has some kind of problem. By the way, it was submerged in fresh water, not sea water, so that is a little better.

The make of the engine is Peugeot. It sounds indeed as if at least one cylinder is missing during start. Fuel system is also a good suggestion I haven't looked at at all yet.

[SkiprJohn]

Aloha Hafskip,

I think most the folks here started with very little knowledge of how a diesel boat engine works but have experienced a lot and helped others work on their engines to get them running properly. I had a friend show me how to bleed my diesel engine back in the early 80s after I messed up and undid a screw on the fuel injection pump. That was my first eye opening lesson on how a diesel is different than a gas engine.

Just start with the simple things that are familiar and learn as you go. Removing a starter is an easy one. Taking it apart and knowing what your looking at is a bit more daunting but doable especially if you have a person with more experience looking with you. You can always take it to a shop for a test or rebuild if you don't want to tackle it yourself.

Removing injectors is easy too as long as you check a manual to see how they come out. The piping going to the injectors needs some care not to crimp or bend or twist too far out of shape. The copper washers you find in the system are good to replace after a few times being tightened down.

If you want to do a test on whether a cylinder is firing properly then get your engine running then loosen the nut on the top of an injector until fuel is pumping out of the pipe. Don't take the pipe/tubing all the way off but just loosen it. If the engine doesn't slow or sound different when you do that then that is the cylinder that's giving you problems. If your engine slows or missfires when that injector is losing fuel then it is good so tighten it back up before your engine stops so you won't have to bleed that injector. It's kind of the same principle as taking an ignition wire off a spark plug in your car to see whether it is missfiring on a cylinder.

Good luck on your trouble shooting.

[hafskip]

Took the injectors out and brought them to a shop for testing. The said the spray patterns were really bad and that new nozzles were needed. So they will replace the nozzles and I'll give it another try.

Just wondering whether I need to replace the copper washers underneath the injectors (not the ones from the fuel lines)? It seems not so easy to get the old ones out.

[DeepFrz]

Yes, you should definitely replace the copper washers. Do you have a dental pick on board that you can lift the washers with? A small screw driver might work as well or a piece of stainless wire with a small hook bent into it. Vacuum the area well first and make sure the seat for the new washer is nice and clean before installing the injectors.