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1999 35hp Johnson engine trouble

I had the boat out yesterday and she ran pretty good. Quit on me a few times, but of course I had forgotten the spark checker. Ran all day today without issues and finally acted up at the end of the day. I was able to confirm that there was no spark when it died, so it seems to be something electronic as opposed to fuel related.

How do you go about testing the power pack? I'm guessing it will read fine until it doesn't, so I'd have to run the engine until it dies, and then do the testing? Anyone know what the part number is?

I like the way the motor runs (smooth and quiet), and the controls are a TON better than the '88 Evinrude that it replaced. That said, it is quite a bit heavier, and it doesn't run any faster, which is hugely disappointing. That, and it's costing me money to get it going properly, on top of the ridiculously high fuel consumption. I burned through 5 gallons in just 1.3hrs of run time (based on the hour meter on the mini tach). Is it possible that the power pack is affecting overall performance and fuel consumption, or is it one of those things that just works until it doesn't?
 
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Found the power pack info on a schematic. I'll have to take a look at the motor tomorrow to see how it all comes apart. Would be nice to know for sure that this is the problem, but not sure what else it could be???
 
Like I said I have one of these J25TEL3EEM. I have added trim to mine. I love the little motor. I can't help but think your fuel usage will be better when running correctly. 25 horsepower is 25 horsepower so not getting ahead there. I have a friend in FL that has two 1 - 25 & 1 - 35. We have both had to put packs on all three engines in the last two years. No stators or sensors, yet! This is not a recommendation, but you have to make a leap at some point. This system is hard to trouble-shoot for a definite failure. These packs fire out of time (hard on pistons, double fire, no fire till they cool off) all very irritating.

 
Now that you mention it, an erratic powerpack could be causing my tach to look like it's going haywire (if it's sending spark more than it should be).

My motor is a 35hp and the old one was 25hp... that's why I was expecting a jump in performance. For all I know though, I could be running on two cylinders. I'm going to call the joint that I bought the engine from and see if they will warranty parts (they have a 1 year warranty, but it may only be good if they do the service, which isn't an option because they are out of state). Either way, I'll be ordering a new powerpack today.

How difficult is it to pull and replace? I haven't looked at the engine yet to even find where it is, but I'm guessing it's behind the starter based on the schematics that I've seen.
 
Powerpack is on the port side of the motor.----Rectangular black box with 3 mounting screws.-------2 plug in connections at the top.
 
Well, it looks like part of my problem is solved. I put a new powerpack on and my erratic running has disappeared. No more sputtering at speed, and she ran good the last two days without dying on me. Performance, however, is still lackluster, and fuel consumption is atrocious (5 gallons in 1.3hrs of run time).

I currently have a 9" prop and she's hitting 5,800rpm. I tried a 15" prop and lost considerable hole shot and didn't gain me any top speed (still 20mph). WOT was down around 4,400rpm, which is way too low. I think I'll try a 12" prop and see how that one works.

Any thoughts on fuel consumption?
 
I'll take a look at them the next time I'm on the boat.

If the diaphrams are worn out, wouldn't the boat run poorly (it's running smooth and responsive with the new powerpack, just still guzzles fuel and lacks punch)?

Either way I'll check them out!
 
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Well Im glad to hear we are getting somewhere. Just got through talking to my buddy in FL. Just a wild guess here, but haven't talked about it. You wouldn't have taken a 15" engine off & put this 20" engine on the boat would you? That would kill the performance! Long shot, but something is out of whack here & I dont think its fuel pumps. Should run rough & ragged if that much extra fuel (bad diaphragms) is going in the crankcase.
I am interested in the 12" prop as 4400 is too low. You will be getting on the high speed circuit to soon & burning extra fuel. That motor should burn around 3.5 gallons at WOT/hr. Most engines will be 10% of rated HP at WOT only. Backing off will save fuel unless the motor is working itself to death. Dragging the gearcase & midsection would definitely classify as no efficiency. What motor did you take off?

 
It's funny you ask that. Originally, that's exactly what I did. I wasn't paying attention and bought a long shaft motor for a short shaft application. I tested it out anyway and got up to 20mph and burned 5 gallons in about an hour or cruising. I yanked the motor off and converted it to a short shaft by removing the extension piece and swapping driveshafts and shift rods. I put her back on the boat and was expecting some big changes, but I still topped out at 20mph and burned a ton of gas. That's when she started giving me trouble with cutting out, so I changed out the powerpack which solved the issue. Still no performance gains though.

I was thinking the same thing about the fuel pumps.... if it was pumping too much gas, it wouldn't run so smooth and would be hard to start.

I've been trying to stay out of the high speed circuit as it doesn't give me any extra speed, but I'm burning about twice what you're stating.... would love it if I could get down to 3.5ga/hr!

The boat had a 1988 25hp Evinrude on it when I bought it. It ran decently, but I didn't like the controls, it was hard to start, there isn't a kill switch, and I was hoping for more oomph, so I jumped on the 35 when I found it. The Johnson is about 40lbs heavier than the rude, but I was expecting something more........
 
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Not questioning you (guess I am), but TEL & mine (25TELEC) don't have an extension to remove. Did you get a different exhaust housing? I wish I had a 15" too. I put mine on a jack plate. Looks kinda weird! OK, now I guess I'm going to ask what kind/brand of boat. I really want to see it with the 12" prop. 9" would be poor performance on anything but a heavy boat & 15" was too much as a result of too many RPMs lost. Usually you lose about 200 RPM per 1" of pitch. Not too far off from that, but going from 9" to 15" the motor fell so far out of its power range you lost a few more. WOT is the worst fuel economy you should get. Any backing off should make a huge difference. We are missing something here, but can't put my finger on it. Wish we were there! Keep talking to us.
Pull the high speed jet (bottom of the bowl). Top carb should be easiest. Suppose to be 38D. That is approximately .038 diameter hole. Guess someone could have opened up jets? Long shot, but we may be looking for something weird here?
 
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?/----There is an extension on these motors !!----The man said he removed it.------The 25 hp powerhead and the 35 hp powerhead look exactly the same.-----Any chance to see what you actually have.
 
I am under the impression that the only difference between the 25hp and 35hp are the carbs. Is that accurate? Is there any way to to tell what I have by model number on the powerhead somewhere?

As far as the extension, I saw it in the schematics, but it was very difficult to see on the motor until I pulled it apart. The seams are hidden and it looks like a single piece. How hard is it to pull that jet out and check it out?
 
Nope-----The 35 hp models have a bigger bore and more displacement.---The 25 is 500 cc and the 35 is 565 cc displacement.------I can't believe the lack of knowledge , sorry.-------Inspection / testing / trouble shooting is the path forward !!
 
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I stand corrected, sorry. I was thinking they built the motor both ways. 20" mid & with the extention kit. The trim system takes the 45 cu in system (40,48,50hp motor stern brackets, swivel bracket & trim) & I was thinking you had to have 20" for that. My mistake. Guess I can get rid of my jack plate. After I find a short D/S. Those long pans do sort of hide things.
Like racerone says the motors have different bores. 500cc vs 550 or 565cc. I'm horrible at that cc thing.
Of course port timing would be different.
 
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I can't believe the lack of knowledge , sorry.-------Inspection / testing / trouble shooting is the path forward !!

What do you think I'm doing on this board? I'm not here to waste peoples time.... I'm trying to gather knowledge!

I'll take a look at the fuel pumps. What else can/should I be troubleshooting at this point?
 
Some people seem bothered to help those who need it. Expect everyone to be as knowledgeable as them. That’s not what’s this forum is about. Maybe you should take a break if your feeling “frustrated” enough to insult us. You are very knowledgeable but like I said, you seem as though you NEED to help us. You don’t. Racerone.
 
It is encouraging that the displacement is larger on the 35hp. At least it's different than just a bigger carb. Now I just need to figure out what's keeping this engine from reaching it's full potential before I end up with a new e-tec!
 
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Received the 12" prop today. Will be trying it out in the next couple of days. Should be interesting.

On another note, is there a classifieds forum here? I've got some parts that I'd like to sell to help recoop some of the money I've had to shell out for this motor.
 
Tried the 12" pitch prop and performance was marginally better. Slightly higher top speed, but I can't really tell what my WOT is because the tach isn't reading right (it hasn't read right from the beginning).

I checked the diaphragms int he fuel pumps and they looked good. I'm still burning ~5 gallons in 1.3 hours of use. Very little of that was at WOT this time... lots of idling while casting for bait and I made sure to stay out of the high speed circuit when cruising to the next fishing hole....

Any thoughts on what to check next?
 
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