1998 yamaha 200 saltwater series 2 oil issue or something else?

[BlaineAtk]

I purchased this boat not long ago and since I have been having some type of issue. I have had it back and forth to mechanics with no real fix so far.

My engine will run fine for a while at all RPM's then it will randomly start dropping engine speed until it is missing on multiple cylinders. Pull the plugs and they are all wet black and oily.

I have had the carbs checked and synced, always ran good ethanol free fuel with stabil. Changed water seperator and spark plugs, wires. Still same problem.

Could the oil injection system over oil? I had the linkage checked, I'm just lost.

Any ideas?

[rodbolt17]

the plug wires on that model are not replacable seperatly.

can it over oil? yep.
can that be easily tested? yep.

if its affecting all 6 cylinders lets look at things that affect all 6.
oiling,fuel and spark.

do an oil consumption test, the manual gives an output test.
consumption test is quicker and easier.

check the lift pumps.

test the CDI output voltage.

do a Yamaha dealer function search.
find a dealership that employs a master tech and specify that tech works on your rig.

[BlaineAtk]

Thanks! I will take it back to a Yamaha Dealer. When I called Yamaha, I asked the question if it could over oil and was told "have you ever heard of a pump going bad and pumping more than it is supposed too?"

Seemed like sound information at the time. lol

Anyway, Thanks once again!

[boscoe99]

Thanks! I will take it back to a Yamaha Dealer. When I called Yamaha, I asked the question if it could over oil and was told "have you ever heard of a pump going bad and pumping more than it is supposed too?"

Seemed like sound information at the time. lol

Anyway, Thanks once again!

I don't see the pump going bad and over oiling either. I could see the oil control rod coming loose in which case the oil pump would default to the maximum oil flow position, but that is a different issue. And, you said that you checked the linkage and it was too specification.

Even with the oil pump in the maximum position I don't see that causing such an overly rich fuel/oil mixture that the motor would start missing. But...

Have you checked the fuel supply system to make sure that it is not causing a lack of fuel flow at RPM's to cause your problem?

[rodbolt17]

if the oil link breaks and the arm goes to wide open it will smoke and shake like you were fogging it.

I have never seen the pump overoil if properly adjusted.

I have seen the shaft seals and check valves leak.

that's why I do the consumption test.
its quick and easy.


not all dealerships have techs with the same level of training,experience and motivation.


I know several techs with over 16 years experience that have done all 6 course plus a few others that have not and probably will never pass the master tech exam.


if you really really wish to blow the techs mind ask him to check the puddle drains.
they fail rarely but they are a madding thing when they do.

careful testing of the fuel,igntion producing and oiling systems is fairly quick and easy.

in the service manual there is an output test.
this test will require running on premix and testing the oil output from each oil line for a specific time and RPM.

that's why I do a comsumption test.

multiply the output by 6.
this should be the consumption at the test RPM and time.
use a graduated cylinder filled with oil on the pump intake line and test, if it passes its not oil related.

same as the CDI output.
knowing the output is roughly the same as the input and its affecting all 6 cylinders you can monitor stator charge coil output voltage.

on the fuel, I would not suspect all 6 carbs failing at once.
however a leaking lift pump can cause flooding especially when drains start picking it up.

that's the first step in trouble shooting and it starts,supposedly, with the service manager. interrogate the customer.

cannot tell you how many 100 hour services I have done only to have the customer come back saying its doing the same thing.
then the service manager brings him back and I am looking at the work order with no running issues noted.
sometimes these motors need repair not 100 hour routine maint.

1 an accurate description of the issues and how and when they occur.
2 make sure its all on the work order.
3 the tech must step back and eliminate a few things and focus on what system he/she is working on.

[ausnoelm]

that is something that has bugged me big time when I have worked in all sorts of repair operations, people think a "service" will fix faults (and maybe, to a point it may) a service is routine maintenance, NOT a repair, if your motor has an issue, do not take it to a dealer and ask for a service, as mentioned, EXPLAIN if it has some problem that may not be rectified by a service.