2000 200 efi smoking bad and running rough

[tkms002]

Re: 2000 200 efi smoking bad and running rough

Can you explain why a failed pulse valve would cause the oil pump seal to get pushed out?
Thanks
Bruce

 

[sschefer]

Re: 2000 200 efi smoking bad and running rough

Can you explain why a failed pulse valve would cause the oil pump seal to get pushed out?
Thanks
Bruce

Can you post a pic of that..

 

[Faztbullet]

Re: 2000 200 efi smoking bad and running rough

Can you explain why a failed pulse valve would cause the oil pump seal to get pushed out?

A bad/clogged/failed pulse valve will overpressurize the oil tank and oiling system. The onboard tank pressurizes and forces oil to engine oil tank and if pressure is not bleed off (valve)it will force oil thru the oil pump and it can fill the VST with pure oil or a really overrich mixture. Also the pressure can force oil seal in rear of pump to pop out and oil will enter crankcase. I have seen the pressure build up and crack the cap on the engine oil tank also..

 

[tkms002]

Re: 2000 200 efi smoking bad and running rough

Well I finally got the parts. Replaced the pulse valve, the oil pump bushing with the seal and all oil pump O rings. None of these looked bad. Ran for 15 minutes at 1200-1500 RPM and it still smokes real bad. Reving to 3000 causes a real smoke cloud.
Help, what can I try next?
Thanks
Bruce

 

[jeffersondodson561]

Re: 2000 200 efi smoking bad and running rough

Their is no way to tell the strength of a spark by its color, take the properly gapped spark plug and with insulated pliars hold it against the block, if it jumps the gap of the plug outside the cylinder in ambient conditions it is definately jumping the gap in the cylinder with a proper 14.7:1 Air/Fuel mixture.

 

[jeffersondodson561]

Re: 2000 200 efi smoking bad and running rough

Is your oil link rod still attached to your cam follower? If the link rod becomes disconnected or breaks, it will retract to it's WOT 50:1 position. If not the map sensor which is built into the ECM could potentially cause this, as far as the TPS goes it should have come from the factory with yellow index marks that indicated the position of the tps, if you test the tps make sure you use an analog meter not a digital one.

 

[sschefer]

Re: 2000 200 efi smoking bad and running rough

Get the real one... And be sure to look close at the MAP sensor. If it's plugged up with gunk the engine will idle very rich and produce a lot of smoke.

The TPS sensor, if it has one, if out of adjustment can also produce an over rich condition at idle. It's usually accompanied by an off idle stumble.

Once you get the Genuine Merc Service manual you will see how the system works and since you actually have the system you will understand how. It's a pretty simple throttle body injection system but it does depend on reading the throttle position and the manifold absolute pressure to determine the duration of the injector pulse.

Regular maintenance on these engines is checking the MAP sensor, the TPS and the injector flow. There are several other diagnostics that can be done with diagnostic equipment attached to the ECU. Usually a shop will have the equipment and can nail down your problem in a matter of minutes. It's often worth the cost of the diagnostics since it can save you a lot of hunt and peck troubleshooting.

Do you think you might want to venture back to this recommendation?

 

[Faztbullet]

Re: 2000 200 efi smoking bad and running rough

We will likely find out if the MAP sensor is bad sometime this weekend as I sent the fellow a ECU to try.....

 

[sschefer]

Re: 2000 200 efi smoking bad and running rough

We will likely find out if the MAP sensor is bad sometime this weekend as I sent the fellow a ECU to try.....

What a guy!

 

[jeffersondodson561]

Re: 2000 200 efi smoking bad and running rough

Have you looked at the mechanical fuel pump? Follow the gas line to the first fuel pump you find, will be mounted on the block. Even though no oil is mixed here will cause a rich running condition and will cause your symptoms, if the fuel pump has never been rebuilt now would be a good time to do it being 10 years. Never have heard of pressure causing an oil pump to over oil?

 

[Faztbullet]

Re: 2000 200 efi smoking bad and running rough

They dont teach you that in MMI school.....

 

[tkms002]

Re: 2000 200 efi smoking bad and running rough

Still working on getting time to get the spare ECU hooked up and tested.
Thanks to all and I'll keep you posted.
Bruce

 

[tkms002]

Re: 2000 200 efi smoking bad and running rough

Well, I got faztbullet's ECM hooked to my smoking engine and I see no difference. It still runs rough and smokes like crazy. Any other thoughts?
Bruce

 

[Faztbullet]

Re: 2000 200 efi smoking bad and running rough

Check you PM......

 

[CharlieB]

Re: 2000 200 efi smoking bad and running rough

I just reviewed ALL the postings and still do not find whether or not you have tested for adequate SPARK on each cyl, as I pointed out in the very FIRST response to your problem.

A failing stator, trigger or ignition module will cause problems and smoking from non-firing cyl's anywhere from an idle to WOT.

You MUST check spark using an adjustable gap tester set to a 7/16 inch gap.

If you do not have one then search these forums for Joe Reeves instructions on building a simple DIY tester using a block of wood and a few nails.

If spark checks out fine at cranking speed and the problem does not begin until 2000 to 3000 RPM then you will need to test stator, trigger, and ignition module output using a DVA meter to verify that the ignition system is operating correctly. It may be possible to test each plug wire with an inductive timing light at the problem RPM to see if the timing light goes out/fails, indicating a mis-firing cyl, HOWEVER this test MUST BE done under load, IN gear, with the prop in the water, as a 'no-load' condition will NOT produce sufficient load on the ignition system to fully replicate the problem.

 

[tkms002]

Re: 2000 200 efi smoking bad and running rough

CharlieB please see post #13. I noted there that I had good spark on all cylinders. Didn't specifically say I used a tester, but I did as you suggested.
Thanks
Bruce

 

[CharlieB]

Re: 2000 200 efi smoking bad and running rough

"Good" spark at cranking is no guarantee of good spark at RPM. A broken, but abutted trigger wire can spark cranking and at idle, yet begin to fail is soon as the trigger is moved with throttle opening, and two cyl's then begin to misfire.

Pull the plugs (to save your starter and battery) ground all the plug wires, disconnect the throttle linkage, retest spark while moving the throttle/timing lever to wot, watch for any failure. Repeat for each cyl.

A failing high speed winding in the stator will provide good low speed spark, yet begin start failing to provide enough voltage/current for higher RPM spark.

A weak capacitor in a switchbox will work fine at idle speeds, yet begin dropping on or more cyl's at RPM.

A timing light, or an inductive tach, used to verify spark on each cyl, at RPM while under load, can prove or disprove an ignition problem, especially when all fuel systems seem to check out fine.

 

[tkms002]

Re: 2000 200 efi smoking bad and running rough

Charlieb, see questions below.

"Good" spark at cranking is no guarantee of good spark at RPM. A broken, but abutted trigger wire can spark cranking and at idle, yet begin to fail is soon as the trigger is moved with throttle opening, and two cyl's then begin to misfire.

It smokes equally at idle and high speed. More smoke at higher rpm's but I think due to more rpms rather than more missing.

It does sound like it is missing at all RPM's though.[/B]Pull the plugs (to save your starter and battery) ground all the plug wires, disconnect the throttle linkage, retest spark while moving the throttle/timing lever to wot, watch for any failure. Repeat for each cyl.

What do you mean by ground all the plug wires?



A failing high speed winding in the stator will provide good low speed spark, yet begin start failing to provide enough voltage/current for higher RPM spark.

Is the above test for this??

A weak capacitor in a switchbox will work fine at idle speeds, yet begin dropping on or more cyl's at RPM.

And for this??

A timing light, or an inductive tach, used to verify spark on each cyl, at RPM while under load, can prove or disprove an ignition problem, especially when all fuel systems seem to check out fine.

Is there any way to test for this while out of the water using just a water bra?

Thanks
Bruce

 

[CharlieB]

Re: 2000 200 efi smoking bad and running rough

The spark energy HAS TO have some place to go, either ground all plug wires, connect all to a multiple spark plug tester, or leave the rest on the plugs and in the cyl head while testing one at a time. The latter leaves a lot of load on the starter and battery.

Voltage required for adequate spark rises with engine load and RPM, the increasing volume of air squeezed into the spark plug gap creates increasing resistance to the spark. Testing in open air requires a 7/16 inch gap to simulate this load.

The stator has two sets of windings, low speed, and high speed. The load is transferred in the range of 2000 to 3000 RPM, HOWEVER, this only occurs while the motor is LOADED.

Testing the high speed windings of the stator UNLOADED requires the use of a DVA meter or a DVA Adaptor attached to your volt meter. Search these forums for the parts and diagram to build your own adaptor quite cheaply and easily. Once you have the adaptor you can follow the detailed directions in the FREE Ignition Troubleshooting Guide from CDIElectronics.com

All DVA tests can be done either cranking or at idle in the hose.

Some will pull plug wires one at a time while idling to see if there is any change in idle speed. This can seem helpful, I don't like getting 'bit' by the spark and I do not like the possibility of stressing the ignition module (switchbox) by un-grounding a plug wire. I use a spark tester and a DVA meter.

 

[tkms002]

Re: 2000 200 efi smoking bad and running rough

So, to ground the plug wires can I just shove a large diameter wire into the plug connector and screw the other end to ground? I did use a 7/16 gap spark tester when I tested the spark before. All the cylinders appeared to have a good spark at cranking speed. Heck, that tester was <$3, I suppose I could buy 5 more and hook them all up at the same time.
If I can't get a difinitive answer from these tests or I cannot perform some of the tests due to lack of tools or knowledge are there some parts I could try to replace? It is far cheaper for me to replace a bunch of parts than to take it to my merc dealer.
Bruce