1991 Evinrude 150 XP (E150SLEI) with constant alarm and won't go over 3000 rpms HELP!

[stephenpence]

Re: 1991 Evinrude 150 XP (E150SLEI) with constant alarm and won't go over 3000 rpms H

results: not so hot. compressions, CYL 1,3,5: 80, 81, 80. CYL 2,4,6 75,70,71....

 

[stephenpence]

Re: 1991 Evinrude 150 XP (E150SLEI) with constant alarm and won't go over 3000 rpms H

Well, i think the order of business should be to get it firing on all cylinders, then focus on the compression. . i can't expect to burn the carbon out of a cylinder that's not firing, no can i??i've gor a DVA adapter coming in to check the power pack, then i'll check it and the timer base... see if i can figure out why the # 4 cylinder is dead.

 

[TexasHawkeye]

Re: 1991 Evinrude 150 XP (E150SLEI) with constant alarm and won't go over 3000 rpms H

the pump is definitely pumping water.. i have a solid stream coming out at all time. I'll go snag an infrared sensor to see if the engine is overheating. if it is, then i'll know it is the thermostats. otherwise it'll be the sensor. Would the motor still go into slow mode even when the alarm isn't sounding?? also, when i have it on the earmuffs, and the alarm isn't sounding, it'll go up to 5000 rpms no problem.
in another turn of events, i replaced the plug on the #4 cylinder, and when i pulled it after running it, it was damp and i was getting a fuel air mixture steam coming out of the hole. it could be that that cylinder was about to fire when i killed the engine, but seems more likely that something else is going on. i pulled every other plug wire while she ran and the motor stumbled on all of them but #4.. I'll check the grounding on the coil tonight.

NOTICE: An old -- but -- experienced OMC Tech says on another thread -- Do not rev over 1500 RPM's while on the muff -- or -- your internal parts will become external parts.

 

[BonairII]

Re: 1991 Evinrude 150 XP (E150SLEI) with constant alarm and won't go over 3000 rpms H

Might be time to pull the heads to see if there is any visible damage. I'd want to know what's going on in there(carbon deposits, scoring etc) before pulling the trigger on a new powerpack etc trying to get #4 to fire.

The OP needs to decide what he would do if the motor needs major work(new rings etc) to get the compression up. No need to get #4 firing, if he has no desire to tear the motor down(should it need it).

Pulling the heads should give him an idea of how much carbon is in there. If nothing else, he'll have to replace the head gaskets which may increase compression a tad.

 

[stephenpence]

Re: 1991 Evinrude 150 XP (E150SLEI) with constant alarm and won't go over 3000 rpms H

I talked it over with the boss, (pointed out the finer details of the devil we know vs. the devil we don’t… same old arguments for rebuilding vs. buying used) and she has agreed that we at LEAST need to know WHAT’S wrong with the motor before we can make an informed decision on how we want to fix it… so head gaskets are on the way. She seems inclined to rebuild before we buy anyways, so anything less than a complete rebuild will be a success!
SO, since it’s looking like rebuilding the motor is on the table, should I go ahead and get the #4 cylinder firing? Or not worry about it for now and just focus on getting the compression up? Pull the heads, take some pictures and let you experts decipher them?? I can’t tell you how much I appreciate all of the help!!

 

[BonairII]

Re: 1991 Evinrude 150 XP (E150SLEI) with constant alarm and won't go over 3000 rpms H

Nothing wrong with trying to get #4 firing, but if that entails ordering a new PP....I'd wait.

I'd pull the head gaskets and see what's going on in there. Def take good quality pics, so the pros here can get a good look at the condition of the pistons, sleeves, head surfaces etc.

 

[stephenpence]

Re: 1991 Evinrude 150 XP (E150SLEI) with constant alarm and won't go over 3000 rpms H

I'll get the new head gaskets in before the end of the week (i hope!) and i can break it down and see what is happening. for the mean time, i'll check the timer base and pack and see if i can pinpoint what's going on there as well. thanks again for your help... i sure wish this was an easier fix haha...

 

[stephenpence]

Re: 1991 Evinrude 150 XP (E150SLEI) with constant alarm and won't go over 3000 rpms H

Here's an interesting turn of events... so, my in-laws were in town.. and wanted to see where some dinosaur tracks are on one of the local lakes... so i was tasked to take them. In preparation to their visit.. i soaked the cylinders in deep creep over the weekend to see if i could close the gap a bit. WELL, when i got back on monday, and checked the compression.. they were: CYL 1,3,5: 85,87,85, CYL 2,4,6 83,81,81. I was TENTATIVELY optimistic headed out to the lake to finish this round of de-carbing.. so everyone piled on for me to take them across the lake and i slowly idled it up.. and sure enough.. it creeped right past 2500... to 3000.. then all the way up to 4500 before my tach died on me again. Long story short, she ran... fast. i kept her at WOT for a good 15-20 minutes since this was the first time she'd been there in oh, say, 4 years, and then we went and putted around the lake for another 30 minutes.. killed the engine and fished for 2 or so hours, and when i tried to get her back up on top after that.. she wouldn't go... Thinking maybe it was the full livewells, i pulled the plug on them.. still nothing. SO.. i dropped everyone off except my wife at the dock to bring down the truck to load and we took her for another spin. so once i had her at WOT.. around 2500 rpms, my wife took the wheel, and i went to the front of the boat and started throwing my weight into the nose to bring it down.. sure enough, within 2-3 pushes.. the boat planed out and we were back on top clipping along. I know the #4 cylinder is still not firing, so i won't be running her like this again until it is, but this has to be a good sign, right? i'll pull the plugs again tonight.. and replace them. i can't imagine them NOT being fouled after 3 rounds of de-carbing.. and check the compression one more time when they're out. and then get working on the #4 cylinder. The head gaskets are still on the way, so i'm excited to get a look inside of the motor to see a little better what's going on in there!

 

[stephenpence]

Re: 1991 Evinrude 150 XP (E150SLEI) with constant alarm and won't go over 3000 rpms H

To anyone having the same issues as me, it ended up being my timer base. i got the DVA adapter, and checked the ignition system, and the resistance on the #4cyl was infinite. so i replaced it and the plugs, and took it out on the water this morning.. and it LAUNCHED into plane. APPARENTLY one cylinder not firing CAN, in fact, keep the motor from being able to plane! I know i'll need to rebuild for the motor to reach it's max potential, but i had the old girl running at 55 mph. that's fast enough for me for this season!! thanks again to everyone for their help!
In review:
The constant alarm was caused by the fuel system vacuum alarm sensor, which was being triggered by the fuel filter being plugged.
The lack of power was from one cylinder not firing, which was because of the timer base. I checked each plug wire by connecting my inductive timing light to it, and the #4 cylinder was firing sporadically. I then ran resistance and current tests on the power pack, stator, and timer base, and determined that the #4 cylinder trigger was bad inside the timer base/trigger coil. once that was replaced (along with the plugs for good measure) the problem was resolved.

It's pretty important to remember that sometimes, you just have two problems, not one problem with 2 symptoms haha.. i hope this helps someone else out as well!