97 Evinrude 115 - runs like a dog, low max RPM

AdamLotz

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Oct 24, 2004
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Hey guys, hope someone can offer some suggestions.<br /><br />Took an 18' open fisherman out for a sea trial today. The boat was S-L-O-W. Acceleration was weak, and top end seemed low to me. If I had to guess I'd say maxed out we were doing maybe 25-30.<br /><br />According to the tach (which I'm going to "guess" was accurate) the engine idled around 1000 rpm and I think we maxed out around 4100-4200. Dealer "felt like" the right (original) prop was on the boat - and the boat was rated for a max hp of 130 so a 115 should have been appropriate.<br /><br />In all honesty, it just plain felt like we were only giving it 2/3 throttle. I didn't think at the time to check the linkage to make sure it was actually opening the throttle all the way, but lets assume it was.<br /><br />The more distressing thing was the overall acceleration - weak weak weak. It didn't take too long to plane, but it was a slow climb from 2200-3500 rpm. <br /><br />The dealer said "oh well it's been sitting, probably needs a carb rebuild" and they are going to take a whack at it and I left a refundable deposit, will try again in a week.<br /><br />Any other suggestions? Does it seem plausible that the carbs are the culpret here? Anything else that jumps out as wrong? (aside from maybe a prop that is way, way off?)<br /><br />From my reading it sounds like the engine should be hitting ~5000-5300 rpm no problem at WOT. Definitely didn't feel like this guy had it in him - I heard none of that familiar 2 stroke WOT scream in it... but overall it ran smoothly???
 

AdamLotz

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Oct 24, 2004
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Re: 97 Evinrude 115 - runs like a dog, low max RPM

PS: I should mention that the engine did seem to be in good shape overall, no obvious signs of neglect or major repairs... but no idea how many hours. Dealer said "oh the compression was good" but I didn't verify myself.
 

rodbolt

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Sep 1, 2003
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Re: 97 Evinrude 115 - runs like a dog, low max RPM

dont pay for it until an acceptable sea trial is run.
 

AdamLotz

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Oct 24, 2004
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Re: 97 Evinrude 115 - runs like a dog, low max RPM

Well, right, that's the idea. The boat is clean and the price is good. If I hadn't taken it for a sea trial, every other indication was that it was a good deal and ready to go. (ran great on a hose)<br /><br />PS: Grew up in Kitty Hawk, parents used to own the bumper boat place + the Nags Head pier!
 

Solittle

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Re: 97 Evinrude 115 - runs like a dog, low max RPM

This is a red flag for me "Dealer said "oh the compression was good". We have had many posts like this with claims made by the seller. The buyer buys the boat and winds up here later wondering why his motor dosen't run right. CHECK IT YOURSELF especially when the motor did not perform well.<br /><br />By the way that idle is way to high which could mask other problems. You should hit 5500 rpm at WOT. 41-4200 rpm indicates to me that the motor is sick or has the wrong prop or both.
 

AdamLotz

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Oct 24, 2004
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Re: 97 Evinrude 115 - runs like a dog, low max RPM

Well right now my take on it is that they have a week while I'm on vacation to make it run well - if it doesn't during the next sea trial, I'll keep looking. If it runs like I think it should, then I'll call it good to go.<br /><br />Can I get a reliable compression check as easy as pulling each plug and popping in a gauge? If so I may ask them to let me watch them do it. <br /><br />So far every indication is that the dealer is pretty legit, I'm not worried about that, just trying to get to the bottom of what might be wrong. <br /><br />They were certainly helpful and willing to go on sea trial #1 with no issues, and just as happy to take me on #2 after they think they've fixed the problem. The boat is on consignment, so they have a pretty casual attitude about everything - and apparently the owner was up for repairing any minor issues etc that they found.
 

Dhadley

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Feb 4, 2001
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Re: 97 Evinrude 115 - runs like a dog, low max RPM

If the dealer knew the boat had been sitting and suspected the carbs were dirty enough to cause that bad of performance he should have stopped right then. Dirty carbs can cause unhappy pistons.<br /><br />Regardless of which 115 it is - crossflow or looper - it should turn close to 5800-6000 with an average load for longevity. Do the compression yourself or watch them and then go for a ride after they "solve" the problem.
 

walleyehed

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Jun 29, 2003
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Re: 97 Evinrude 115 - runs like a dog, low max RPM

it should turn close to 5800-6000 with an average load for longevity.
This is a KEY element here...when they get it running right, make'em prop it right too.
 

AdamLotz

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Oct 24, 2004
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Re: 97 Evinrude 115 - runs like a dog, low max RPM

Can anyone fill me in on what the proper compression range should be for this engine?
 

Dhadley

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Feb 4, 2001
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Re: 97 Evinrude 115 - runs like a dog, low max RPM

As long as the compression is within 15 lbs from hi to low. We look at the difference not a specific number. Actual numbers will vary with proceedure, heads, head gaskets and gauges.
 

AdamLotz

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Oct 24, 2004
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Re: 97 Evinrude 115 - runs like a dog, low max RPM

Thanks Dhadley, that's what I figured. Just got back from vacation and going to swing by this afternoon or tomorrow for my 2nd sea trial...
 

AdamLotz

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Oct 24, 2004
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Re: 97 Evinrude 115 - runs like a dog, low max RPM

Well, second sea trial went better but still not great. They put some work into the carbs, and the engine would do ~4800 rpm trimmed down, and ~5200 at the very peak of what it would do. <br /><br />I debated for a while, but today decided it just wasn't worth the risk, I just wasn't happy with the performance overall.<br /><br />Of course, I go back to get my "refundable deposit" and the guy freaks out on me. He wants to "talk it over with the owners" and have me get back to him tomorrow.<br /><br />Not happy.
 

Dhadley

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Re: 97 Evinrude 115 - runs like a dog, low max RPM

At 5200 max that motor isnt happy either. With a bit of set up tweaking it may be OK but always go with your gut feeling.
 
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