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84 Evinrude 60hp twin compression and wot rpm range

Sttuppid

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I am thinking hard on the purchase of a 1984 Corson 15 ft runabout in near-perfect original condition. It has the original 1984 Evinrude 60 hp twin with power trim/tilt and I took it for a 15 min test run, and it runs great but only maxes out at 4800 rpm, which seems low and unhealthy for that engine. I'm unable to locate the correct WOT rpm range. It has a 13x19 prop in good shape but is only revving to 4800 rpm. I have the service manual, but it doesn't say the recommended RPM range. I was thinking of putting a 17p on it to gain around 400 rpm, but I simply cannot find the correct WOT rpm range. Thanks. Also, It has a full gauge package installed; I believe they are Faria VDO? gauges, and I am unsure what I
should set the "poles" to. Currently, it is set for 2 poles; is that correct, or should it use the stator poles instead? Here are a couple pictures of the unit. And last but not least, I am going to do a compression test on the cylinders, and I am unable to find what that should be? Thanks again
 

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I am not sure, but the owner (original owner) said he thought it was about 4700-4800 with the 19p prop, which he put on to give him the right trolling speed. When I ran it, it showed 4800. However, he is 80 years old and suffers from prostate cancer, so he rarely ran it at full speed. He possesses the original 13x17p prop for the boat. Generally speaking, that should bring it up to 5300, I think. I have found several variations of the recommended wot...some say 55-6000, another says 51-5800, and yet another says 5000-5500. Additionally, should the 1984 60 hp twin engine use a 50:1 mixture or a 40:1 mixture? Also, that boat sat for the past 5 years shrink-wrapped in dry storage at the marina, and he had them give it a tune-up and lube the cables, wash and wax it, etc. They rebuilt the carbs, replaced the plugs, and lake-tested it for him. I have not checked the compression but will before I hand over the money, but I don't know what it should read. Thanks, guys.
 
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I don't know how much it cost to take it out of storage and tune it up, but he has all the marina's receipts. He claims to have all the records and receipts from the original purchase price and all the work done to it during its life, as he bought it from that same marina. He had it winterized and shrink-wrapped every year, and he kept it in his garage when not in use. It is almost stunning the condition it is in for being 41 years old. He has put all that together for me to look over when I go up today to decide to take it home or not. He is asking 5500 for it, and I tried to get him down to 4500, but no go. He said it cost him 6k for the five years of storage and the tune-up. Seems like a very honest, kind man. However, it is a lot of money for a boat of that age? I really like the condition and simplicity of that boat. It doesn't have much deadrise, but it seemed to ride pretty well. I went over some wake waves, and the boat felt firm but did not pound.
 
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Sorry, boat is no name, nothing special other than clean. I buy boats and wouldn't do more than $2500. Who cares what the storage bill is, has nothing to do with the boat's value. I learned from my father years ago, keep emotions out of buying stuff, that nice guy wants to take your money based on some preconceived notion of value. Make an offer that you can live with and write it down on a piece of paper and tell him to call you and it will be going to a good home. I watched dad buy "valuable" stuff for $.50 on the dollar, because he was willing to walk away. It works!
 
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Hi everyone, I brought the boat home! Compression was great: 135 top, 137 bottom. It starts right up and idles great, but I think it is a bit slow; I will check it with my tiny tach. It shifts instantly without any banging or grinding. I am pleased with it and need to register it today, as well as adjust the tach settings. It is a VDO gauge with 6 dip switches. The trailer pulls great; I drove it on the highway at 60-70 mph for 80 miles without any swaying, and after stopping a couple of times, I found that the bearing buddy hubs were just lukewarm. The lights work as they should, but one of the lenses has a small section that is broken off, but no issue. The mixture is 50:1. The RPM range is indicated on the engine ID plate as 51-5800. and peak HP is labeled at 5500. Thanks for all the help!
 
Sorry, boat is no name, nothing special other than clean. I buy boats and wouldn't do more than $2500. Who cares what the storage bill is, has nothing to do with the boat's value. I learned from my father years ago, keep emotions out of buying stuff, that nice guy wants to take your money based on some preconceived notion of value. Make an offer that you can live with and write it down on a piece of paper and tell him to call you and it will be going to a good home. I watched dad buy "valuable" stuff for $.50 on the dollar, because he was willing to walk away. It works!
Boat is a Corson, they were extremely good boats that were handmade in Maine. https://maineboats.com/print/issue-146/classic-maine-plastic
 
I'm glad you're happy with the purchase, hopefully you'll be able to keep it in the same shape it is in, hopefully in a garage. Good luck with her.
 
I'm glad you're happy with the purchase, hopefully you'll be able to keep it in the same shape it is in, hopefully in a garage. Good luck with her.
Maiden Voyage went excellently! The engine started up after pushing inward on the key switch, which activates an electric primer for a couple seconds, and it idles perfectly at 750-800 RPMs. The transmission is completely silent when the boat shifts into gear. The boat comes up on plane with nearly zero nose rise and stays on plane down to 15 mph at 2600 RPMs. The throttle range exhibits no flat spots, and it reaches its maximum speed of 4,800 RPMs at 33 mph, according to the GPS. I will drop down to a 13 1/4 x 15p prop, which should get it up to 5,000-5,100 RPMs. Currently, the boat is equipped with the original 13 1/4 x 17p prop, which has no cupping. The hull weighs 700 lbs., and the 2-cylinder 60 hp Evinrude engine adds about 200 lbs., two 160 lb. people, two 6-gallon fuel tanks full, and a huge marine battery that weighs at least 75 lbs., in the rear, so the total weight is around 1300 lbs. It makes me think that it's 17p would it be able to let it rev higher? It has a variable, a deep-V in the nose to a 15-degree deadrise in the stern, and it was very windy with a 1 ft. chop with broken water caps, and she rode better than I thought she might. When going against the crosswinds at 10 mph, the upwind side splashed out enough in the bow to get a bit wet if trimmed down, but trimming it up at that speed stopped it from blowing the water up in the nose, and running on plane slightly nose down in that heavy chop was more tolerable. The wind died down after a couple of hours, and it was wonderful as the large lake calmed down. I encountered three issues: the trim very slowly creeps down over 15 minutes. I am certain that the bleed-down screw is leaking, as it affects both the trim and tilt cylinders. Is there a way to simply plug the bleed-down? The screw/O-rings are no longer available. The speedometer doesn't work, and I am not sure why, as the line is clear, as I blew it out first with my mouth and then with the air nozzle when I got home in the garage (30x60 heated shop), and the hose seemed clear? Lastly, the navigation lights are not working; it's a simple fix. We were out for about three and a half hours, and I was pleased to find that I only burned about half of one of the 6-gallon tanks. Additionally, the taillights burned out immediately upon entering the water. I believe they are original parts because the lenses are cracked and not waterproof. I ordered a new harness with LED sealed taillights. The harness is in rough shape with multiple repairs done and corroded wires. I think this boat will last me at least another 10 or more years, and by then I will be too old and lame to deal with trailering it anyway. I am satisfied with the unit. I love the top cover; it keeps the sun and rain off you all day and has the original side curtains that zip on. I will provide updates as time progresses. Thanks, everyone.
 

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