Black Max 150 has me baffeled

[kendo]

Re: Black Max 150 has me baffeled

John,
I Just recently replaced the stator. Have you known them to be bad from the factory or did it get fried for some other reason. High speed coil seems to be what I am lacking, could The inner magnet of the flywheel cause a problem with the trigger. When I checked the magnets the outer ones were a lot stronger than the inner one using a screwdriver as a probe. I'm going to try the timing light test, switching the switch box's is no problem if need be. I can't really feel a missing at high speed and all plugs seem to be the same temp when touching them. I agree about the carbs, they dont leak or change speed while pressing the primer bulb. I'll leave them alone for now. What do the 3 coils in the trigger do and would they hamper the strength of the spark to the coils? I'll test the stator with the ohm meter again just to make sure all coils are functioning. I started to doubt myself and rechecked several things including timing and compression which is still at 120/125 per cyl. I'll keep you posted, thanks Kendo!

 

[jims3000]

Re: Black Max 150 has me baffeled

a friend of mine was having a simular problem would not get to top speed.he rebuilt carbs ck fuel done everything he could think of.i went with him on the boat last week to try and find the problem he ran the boat at full throttle while i adjusted the carbs and ckd the timming adjustment and we found the timming was advancing to far.the motor sounded fine at full throttle no misses but would not run it pottential until i set the timming runs great now.

 

[j_martin]

Re: Black Max 150 has me baffeled

Kendo,
When you set the timing, did you check the .462 mark on the flywheel?

You find the top of the throw, then go around again to TDC - .462" with a dial indicator or depth gauge, then set your timing pointer to .462 on the flywheel. Only then are your timing adjustments valid.

The trigger magnets aren't as strong as the alternator magnets. They only have to create a signal, not real power. If they were weak somehow, it wouldn't even start, as the weakest current would be at cranking speed.

I believe the trigger is set up on one pair of magnets, and each coil has a center tap, with that grounded and each end of the coil going to one of the switch boxes, thus when N goes by a coil, it fires it's plug on one switchbox, and when S goes by, it fires the other. Usually when a trigger goes, it takes out 2 cylinders, one on each bank.

Is it remotely possible that the core of your boat got waterlogged? It's pretty easy to pick up 500 lbs that way, and it really loads the motor down. I think you said you tried a shallower prop though, which would compensate for that.

When you're playing with the light, if it's possible to shine it on the timing marks, look for obvious misfires and prefires. You could put a chalk mark on the flywheel roughly 1/6 around from the b23 mark for reference for each cylinder. It's very remote, but you might have a hidden crack in one of the trigger magnets that's causing trouble. Just don't get dumped over the transom messing around.

It is possible to get a bad stator new. It's possible to miss the grounding of it, either through a seperate lead or 2, or by the screws into the bearing cap. It sure looks like a high speed miss to me. The plugs would heat up in a hurry to normal as you came back down to the low speed side. You might not feel a miss at high speed, especially if it happened on 3 evenly times plugs and "phased" in as one would expect with a bad stator. I have a known good 16 amp stator that would probably fit if you need to try it.

Still offering to help if you're anywhere near close to me.

John

 

[kendo]

Re: Black Max 150 has me baffeled

John,

I'm taking a break for the Holiday, plan on getting into it after that. Just to let you know I picked up a digital caliper from menards, made a bracket and tested for .462 and tdc. .462 was nuts on and I did the link and synch after that. Timing is spot on 11atdc and 18btdc will test more on Tues/wed. weather permitting. Also will be taking timing light with me checking for misfire at speed. After that, I'm going to get serious. Wife says riiiiight. Thanks, Kendo

 

[rkrueger]

Re: Black Max 150

Re: Black Max 150

Hello i am putting a black max 1987 150 oil inj. on a 1974 starcraft...but i need some wiring diagrams to make sure all is hooked up right any other head aches i might have ! power trim diagrahms also! randy!

 

[kendo]

Re: Black Max 150 has me baffeled

Randy, I havn't figured out my own problem yet but I sure have learned a lot along the way. Not being outboard savy I was intimidated the first time I took the cowling off that monster. Since then I have gotten to know that engine pretty well with the help of the Seloc Marine manual for that motor and the guys that have contributed to this sight. The Seloc manual has a complete wiring diagram with actual pictures and explanations of your motor. Just determine what model you have and it's all right there. It was $35.00 well spent, I'll use it as long as I have this rig. Beats 75.00 to 80.00 bucks an hour at the dealer plus you get personal satisfaction.

good luck. Kendo

 

[studlymandingo]

Re: Black Max 150 has me baffeled

You definitely want a manual for your motor; there is tons of invaluable information. If you plan to wrench on it yourself, without question, get a good manual.

We're all waiting for Kendo to get back from holiday to see what is going on with the beast!​

 

[kendo]

Re: Black Max 150 has me baffeled

Studlyman,

I'm back at it again. Here's where I'm at. Took her out with the timing light and checked all cylinders for any type of miss with negative results, all seem to be firing although hard to tell at higher rpm. Light just goes solid. Brought her back to the garage and pulled the carbs. All appeared normal, right jets and adjusted the floats to spec. Checked reeds at the same time all are there and have tension. Also removed the exhaust cover and baffles to check for obstruction, there were none. Pistons are clean, no scuffing and ports are clear. Put her back together. Took her out for a run, ran the same 3900 rpm, 32 mph. Only thing left at this point is the trigger and flywheel. Saved up enough to order a trigger assembly from Boatfix, Inc, $84.00 not to bad. Should arrive on Friday or Monday. If that doesn't work I might have to hit John up for that spare flywheel he has. Thanks for the interest, I'll keep you all posted. Kendo...

 

[j_martin]

Re: Black Max 150 has me baffeled

A bad trigger or a flywheel would cause a misfire that you could see with a timing light.

Are you sure you don't have a waterlogged boat, or way too high pitched propeller?

John

 

[skidplate]

Re: Black Max 150 has me baffeled

Had same problem with similar motor and spent lots of money on electrical and fuel related parts. Finally found a real mechanic who diagnosed my problem in 15 minutes. My problem was too much fuel and it was being caused by the "choke solenoid valve. The needle within the valve had broke and was dumping fuel into the carbs all the time. Before the valve was replaced I was only able to run at 25 - 3000 rpms and raw fuel was dumping out of the exhaust. Quik test is to diconnect or plug the fuel line fron the solenoid.

My 2 cents skidplate

 

[kendo]

Re: Black Max 150 has me baffeled

Skidplate, thanks for the suggestion, I will give it a try the next time out. In the past when trying to add gas while under way either by spray bottle or choke solinoid the engine always bogged leading me to believe she was not fuel starved. Also piston domes have normal carbon deposits and no sign of seizing. On the bright side I'm getting real good at launching this rig, won't be blamed for tying up the boat landing ever again. Kendo.

 

[kendo]

Re: Black Max 150 has me baffeled

A bad trigger or a flywheel would cause a misfire that you could see with a timing light.

Are you sure you don't have a waterlogged boat, or way too high pitched propeller?

John

John, just to eliminate one more possibility I'm going to weigh the boat this weekend. I know about what she should weigh minus the trailer. As for the prop when I went from the 21 to 19 there was no differance in rpm. I'm liking the last post having to do with the choke solinoid. I know my snowmobiles don't rev. when I accidently leave the choke half on. Kendo

 

[kendo]

Re: Black Max 150 has me baffeled

Well John you were right, the new trigger assembly didn't make a differance. Also tried Skidplates suggestion of cutting off the fuel from the electric enrichner with a locking surgical tool which made no differance. Still 3900 rpm. Engine definetly seems to be missing at mid speed, 3000 rpm level and refuses to pull high rpm. Still feel in my gut that the timing is off, just don't know how to get it on. Conventional method isn't doing the trick. Sorry to say that I'm going to hang this project up real quick before I run out of summer. Have a house to paint and a son getting married in June. Oh and I have to go to work once in awhile. Work is another 4 letter word that ends in "K" you know? Everyone, Thanks for the help, Like Arnold says, "I'll be bock" Kendo from Wi.

 

[AndyL]

Re: Black Max 150 has me baffeled

G'day, Nothing too technical, but have you tried firing her up in the dark with the cowling off to make sure you aren't getting any electrical tracking to earth (ie bolts of lightning) off the wiring. It may be something simple as that which is bringing the electrical power down. Looks like you are getting superb technical help elsewhere so this was just a more rudimentary idea.

Good luck and hang in there.
Andy

 

[kendo]

Re: Black Max 150 has me baffeled

Andy, thanks for the idea, I did this years ago with a car that was giving me trouble and found some arching on the plug wires. I had forgot about that and will try it soon. You are right I have gotten some great help and I appreciate this forum. Kendo from Wi.

 

[AndyL]

Re: Black Max 150 has me baffeled

Hey Kendo... Any luck yet??
Andy

 

[kendo]

Re: Black Max 150 has me baffeled

Andy, thanks for the interest. I tried the trick of running her in the dark and could not see any stray electrical charges just a nice glow under the wire cap. Kept a close eye on the coils and wires but saw nothing. Had to put the project on hold for awhile but will start working on it again. Went for a ride the other day and noticed a miss on cylinders 2 and 4 with the timing light. I'm looking for a pair of switch boxs now just to try that again. I hear if you change 1, change them both. Wish I had a bunch of parts laying around. We have a boat swap meet coming up in Aug. I'll be there looking for cheap parts. Still think it's electrical. Good thing I have another boat to use (15 ft. aluminum with 35 evinrude) while I play with this one. Thanks, Kendo....

 

[kendo]

Re: Black Max 150 has me baffeled

Well, it's 09/09/2007 and this story finally has a happy ending. This motor had many problems and through elimination, replacement parts and repairs I can now say that she's a great runner. I also have become somewhat of an expert on this particular model with the help of all the contributers to my post. It turned out that upon inspection there were 2 different types of carbs on this motor when all should have been the same. The top 2 were WH-35's, 34.5 mm and the bottom 4 were WH29's, 39.5mm which were the right ones for this motor. When and how this happened I will never know. I can only suspect that while being repaired possibly by the previous owner the wrong carb was installed by mistake by a careless mechanic working on more than one motor at a time. They look the same except for the rear ventury area and have the same bolt pattern. Also found one coil that worked at low speed and failed at higher rpm's. Upon testing on the lake I had a great hole shot and reached 5800rpm and 52mph. At this time I am under propped as you may remember I went to a 19 inch pitch trying to pick up more rpm's. Special thanks to John Martin who hung in there with me through this trying ordeal. Happy boating, Kendo from Wi.