Mercury 200 blackmax serious help!!!!!

[wameyer]

OK, I am new to the forum. I did a search to try and find some symptoms that were the same on my boat but not much luck. I have a Blackmax 200 carbed motor with serial number 0b264023( I hope that correct). Alright let me start off by saying whats happening. I can put the but in throttle and rev it up it works great. When i put it in gear it will stay in "granny" gear and wont go any faster. The first time I had it on the water it would go FAST and when I stopped and let it sit for maybe an hour thats when the trouble started where it was in "granny" and when I went full throttle the motor would die. But would start up and rev in neutral with out a problem.

OK. I replaced the water pump when I first got the boat, I just replaced my t-stats. I really need some help I can try to explain more if needed to help diagnose I just want to be on the water and be able to enjoy my boat and motor without having to work on it and not showing any progress.

Thank you for any and all help.
my email is anthonymeyer_9@hotmail.com

 

[nbnewbie]

Re: Mercury 200 blackmax serious help!!!!!

don't take offense sometimes i can't seem to type for crap either but please clarify "I can put the ?but? in throttle and rev it up"
##
"it will stay in "granny" gear" not a term i'm familar with but if i'm understanding the problem at all it's that in neutral it will rev up ok under a "load" it fails my first inclinitation would be to check the fuel pump it might be delivering enough fuel to run "no load" but failing under load there are some ways to test of course but the kit for that fuel pump is probably about $20 and relatively speaking "an easy fix" good luck

 

[wameyer]

Re: Mercury 200 blackmax serious help!!!!!

Also when I start the engine up water will come out of the tell tale nozzle for alittle bit then it turns to steam. I then shut it off.

 

[wameyer]

Re: Mercury 200 blackmax serious help!!!!!

yes what you are saying is correct. I was trying to relate it to a car by saying granny gear. But under load it will not really move and when in neutral it will rev up without a problem.

 

[j_martin]

Re: Mercury 200 blackmax serious help!!!!!

"So what is going on", says the newbie...

With no load, it'll idle and rev with no load on very little fuel and missing some cylinders. It's a totally worthless test.

You need data to figure out what's wrong with the engine. First thing you need is compression data. If that's not good, nothing else will fix it period.

Then you need to check spark on all 6 at idle with a spark gap tester. It doesn't take much to jump the .040 gap in the plug with no compression in open air. You need enough spark to jump 7/16" in open air.

That good, then you go on to the fuel system. History helps here. Is this the first or second trip after storage for awhile? Has it been through a rain and windstorm that could have fouled the fuel? Does squeezing the primer bulb help.

If you plan to work on it yourself, get a mercury maintenance manual for it. Also lurk on this board for a few hours and pick up some of the marine engine lingo. We don't have gears, much less granny gears for instance.

hope it helps
John

 

[nbnewbie]

Re: Mercury 200 blackmax serious help!!!!!

the newbie... wasn't saying anything as a solution it was simply a suggestion if taken otherwise wameyer, i appologize note that i also stated there are other tests that could be performed i have from time to time taken a $20 shot in the dark (that would do no harm) and lucked out besides what i was speaking to was not presented as a "test" worthless or otherwise it was a symptom to me there's a big difference

 

[wameyer]

Re: Mercury 200 blackmax serious help!!!!!

I really appreciate nbnewbie. I will try that. I know I am getting spark and all on all my SURFACE gap plugs as recommended in the book. I know it wont hurt to buy the kit for it. The only thing I know the first time we had it out before it messed up, it was a blast then when we stopped it the fun ran out trying to get back to the dock. I will pick up a fuel pump kit tomorrow.

 

[j_martin]

Re: Mercury 200 blackmax serious help!!!!!

The newbie I was referring to was the original poster, wameyer. If the shoe fits.............

Anyway, advice still stands. Hope it helps
John

 

[wameyer]

Re: Mercury 200 blackmax serious help!!!!!

OK, I did a compression check last week and found that on one of the cylinders it was low. I pulled the head and what do you know a warped head. I had both heads decked/shaved to where they are both flat. Got new head gaskets and torqued everything to the required torque and in the specified sequence. I tried going on the lake today and still no luck. When I have a load on the motor in forward the motor will not get up on plane. When I have it out of water with the flush kit the motor works fine. My plugs are good and working, all coils are fine. There is zero blow by on the piston walls. My compression readings were exactly where they were supposed to be.

I have fuel and I know it is pumping to the motor. I also have oil for the oil injection. Put a new fuel filter on and a water fuel separator. I rebuilt the fuel pump. Replaced ALL the fuel lines and oil lines. Any help would be appreciated. I dont know if this matters or not. The motor is on a 25ft glasstream eagle 2500 with an ocean drive mount to put the motor deeper in the water. It also has a laser ll 21 pitch on it. Did not know if these are factors or not. Thank you for any help.

 

[njrextreme]

Re: Mercury 200 blackmax serious help!!!!!

Sounds like an electrical problem. I would suspect weak or intermittent spark. Try pulling a plug wire one at a time and see if it changes the way it runs. Does the motor rev up real fast or more of a slow/flat rumble rev? If you can pull one of the plug wires and there is no change, it has spark problems.

 

[wameyer]

Re: Mercury 200 blackmax serious help!!!!!

it will rev up fast. All my coils are good I am getting spark from them. I have been thinking it was an electrical issue from the start but then second guess myself. The motor does not want to do anything when there is a load on the motor. When I had the boat on the trailor and tied down to the trailor and to the truck I put it in reverse and the boat was trying to pull the truck in the water.

 

[j_martin]

Re: Mercury 200 blackmax serious help!!!!!

Has it ever run well in this setup? We run a 22 or 24 inch prop on that engine for an 18' bass boat, usually with the prop piercing the surface. 21 sounds a bit high for pitch, especially for a non ventilated prop.

With no load, that motor will scream when hitting on 2 cylinders. If spark on one bank were weak, it could idle perfectly, race to the moon on the cups, or in neutral, and drop 3 cylinders immediately if throttled up under load, raising the discharge potential for the spark plugs.

You need to acquire a spark gap tester, about ten bucks at the auto parts store, and check for a strong long spark on all cylinders.

You may need to do some other tests. We'll get there one step at a time.

hope it helps
John

 

[wameyer]

Re: Mercury 200 blackmax serious help!!!!!

Someone told me that it could be the advance spark on the top of the motor where it advance the spark when you drop it in gear. I know anything is a possibility but should I even check that .

 

[Wingedwheel]

Re: Mercury 200 blackmax serious help!!!!!

If it revs up but just won't go it could be a spun hub in the prop..My02

 

[wameyer]

Re: Mercury 200 blackmax serious help!!!!!

Thats the thing. the boat will somewhat move. When i put it in gear it starts to go but when I go to start trimming the motor down while giving more throttle the motor starts to die. nothing appears to be blocking it from getting any air and the fuel is getting to the motor.

 

[j_martin]

Re: Mercury 200 blackmax serious help!!!!!

Someone told me that it could be the advance spark on the top of the motor where it advance the spark when you drop it in gear. I know anything is a possibility but should I even check that .

The advance module has nothing to do with shifting. It runs strictly on engine rpm's.

I have asked you specific questions, and given you specific direction. Systematic diagnostics is the fastest and least expensive route to a solution.

 

[Superjetjim]

Re: Mercury 200 blackmax serious help!!!!!

Have you stripped and cleaned your carbs/jets? - could be gummed up or partly blocked.. they all run great under no load as mimimal fuel is required hence why above needs to be checked.

 

[wameyer]

Re: Mercury 200 blackmax serious help!!!!!

OK, I tested the 7/16" open air gap and all but one coil jumped the gap. I checked before and all my coils would jump the plug gap. So now what do I need to do.

 

[j_martin]

Re: Mercury 200 blackmax serious help!!!!!

OK, I tested the 7/16" open air gap and all but one coil jumped the gap. I checked before and all my coils would jump the plug gap. So now what do I need to do.

Swap the coil with a known good one and see if the bug follows the coil or the switchbox driving the coil. Now's a good time to detail the connections and grounds for the suspect coil.

FYI, it takes a lot less to jump a spark gap in open air than it does to jump the same gap under compression.

hope it helps
John

 

[wameyer]

Re: Mercury 200 blackmax serious help!!!!!

ok, will do. Heres the funny thing the other week after we got back from the lake my brother decided to change the transom oil. Low and behold it was good so he put fresh oil in. Then we did nothing this morning I tested the air gap for the plugs and as you probably read above the one coil on the port side bottom did not jump. We still said screw it lets go out on the lake and at least pull in a cove to have some fun. After we set in the cove for a few hours we said lets go home and when we left my brother pushed the throttle all the way down and voila we were haulin @$$ on the water. We did not change the coil or nothing the only real difference he changed the oil on the transom. We are going to go Monday to see if the motor works well again or what. Any ways will keep you posted and thanks for the help.