BillM Posted June 23, 2015 Report Posted June 23, 2015 Compression should be the same no matter how the engine is started (pull or electric). Should be around 200.. What you want to make sure of is that all cyls are within 10% of each other.
BassMan11 Posted June 23, 2015 Author Report Posted June 23, 2015 OK i'll check that tonight. Hopefully it will be up around those numbers. What numbers does the compression start to be a concern? 150-100? Thanks for everyone's help so far. I hopefully didn't buy a lemon.
porkpie Posted June 23, 2015 Report Posted June 23, 2015 If it's running at 100 psi, it won't matter how close the cylinders are compression wise, you probably have issues. Keep in mind I'm quoting numbers for a 50HP, but I imagine the 30 would be similarily high. Remember to advance your throttle when doing the test. Good luck.
BassMan11 Posted June 23, 2015 Author Report Posted June 23, 2015 If it's running at 100 psi, it won't matter how close the cylinders are compression wise, you probably have issues. Keep in mind I'm quoting numbers for a 50HP, but I imagine the 30 would be similarily high. Remember to advance your throttle when doing the test. Good luck. So open the throttle in neutral when testing?
porkpie Posted June 23, 2015 Report Posted June 23, 2015 Yes, I think the factory spec calculates it at 500 rpm. Most ATV's need to be tested with the throttle open as well. If you run it until warm on the muffs before the test, you''re likely get your best readings. I'm sure it will turn out ok, but it just rules out one more thing. Good luck.
BassMan11 Posted June 23, 2015 Author Report Posted June 23, 2015 Didn't have the room to pull out the boat and throw the muffs on. But I did a compression test on all three cylinders. Top - 136 Middle - 133 Bottom - 135 Are these numbers ok from a cold start? Can I rule out compression being an issue?
Fisherpete Posted June 23, 2015 Report Posted June 23, 2015 Just for comparison my 16' Legend with 30 Honda gets 27.5mph when I am solo, 24.5 with a 200lb passenger. Boat weighs around 1000lbs with motor batteries etc. included.
BassMan11 Posted June 23, 2015 Author Report Posted June 23, 2015 Thanks Pete. That's what I figured. My boat is 1000 with 2 people included. I was looking to get close to 30 so when I was struggling to get 15-17 by myself I knew something was up.
porkpie Posted June 23, 2015 Report Posted June 23, 2015 Didn't have the room to pull out the boat and throw the muffs on. But I did a compression test on all three cylinders. Top - 136 Middle - 133 Bottom - 135 Are these numbers ok from a cold start? Can I rule out compression being an issue? I really am not sure with the 30, so I am talking out my proverbial behind here. When I bought my 50, compression from a cold (it was minus 8 out at the time) was around 175 across all cylinders. Factory spec called for 199psi. I was satisfied because the engine was cold, and it was a 1999. It runs great and carries a 16 foot boat with full interior and console, 2 guys at 230lbs a piece, 3 batteries and full of gas and gear at 30mph in perfect conditions with a tail wind. I likely wouldn't have bought the boat with 135 on all cylinders. BUT, it's not a 30hp. I suggest you call a honda dealer, explain the situation and see if they will give you the factory compression for your motor. They should be able to help you out with year also. Hopefully your compression is good for the year/motor. Good luck with it.
BillM Posted June 24, 2015 Report Posted June 24, 2015 Those compression numbers are fine according to a few Google searches I've come up with.
BassMan11 Posted June 24, 2015 Author Report Posted June 24, 2015 Those compression numbers are fine according to a few Google searches I've come up with. I agree Bill..... reading just about everything I can on the interweb the general consensus is they are pretty good. Plus I talked to my mechanic buddy yesterday and there is a feature on the pull start Honda outboards that lower the compression when starting so it is easier to pull so that's why I don't see anything near 200. It's called auto decompression I believe. Going to dump a bunch of seafoam in the tank and give it a good run this weekend. Next week I will start looking at flushing all the fuel lines and possibly change the fuel pump. I think we have narrowed it down to either a fuel issue or an air intake issue.
Sinker Posted June 24, 2015 Report Posted June 24, 2015 It would help if you knew what RPM's you were running. A buddy at work had a similar issue with a 25 merc 4 stroke. Boat wouldn't plane, and lack of power. Turned out it was his prop.....over propped. Try the seaafoam though, and I would try it with a new fuel line as well. I had one do something similar on mine, and it was the fuel line. It was eaten up by the ethanol in the fuel. The line looked fine, and seemed to work fine, but after replacing it and having a look at the inside, it was all gunked up with crud and hardly any fuel was getting by. S.
porkpie Posted June 24, 2015 Report Posted June 24, 2015 If the engine has a decompression feature that would account for those numbers. Most quads with a rope starter have a decompression lever or you'd tear your arm out of the socket trying to turn one over.
BassMan11 Posted June 24, 2015 Author Report Posted June 24, 2015 It would help if you knew what RPM's you were running. A buddy at work had a similar issue with a 25 merc 4 stroke. Boat wouldn't plane, and lack of power. Turned out it was his prop.....over propped. Try the seaafoam though, and I would try it with a new fuel line as well. I had one do something similar on mine, and it was the fuel line. It was eaten up by the ethanol in the fuel. The line looked fine, and seemed to work fine, but after replacing it and having a look at the inside, it was all gunked up with crud and hardly any fuel was getting by. S. The prop was the original prop for the motor when I bought the motor. I also bought a brand new prop 1 size small but the motor sounded and felt the exact same. Hopefully it is as easy and changing the fuel line(s).
Wagoneer Posted June 24, 2015 Report Posted June 24, 2015 Sounds like a fuel issue. I'm guessing the connector at the motor is sucking air. When you squeeze the primer do you notice any hissing from the engine? Or any air escaping at all? I had a similar problems with my Suzuki 2-stroke outboard. Idle was fine, but anything above half throttle it would bog really badly. Turned out the fuel connector (brand new) was sucking air and not fuel under any sort of load. I swapped it out with a much simpler (and this will be the only time I'll admit to using merc parts) Mercury connector at the engine as well as at the tank and it seals up perfectly now. Even though the Suzuki connectors never leaked fuel when disconnecting/connecting but the mercury ones spill fuel all over the place when you disconnect them, at least the Mercury connectors seal properly under suction. Doesn't really matter what prop you're using, that motor should get you on plane no problem on a 14' boat.
BassMan11 Posted June 25, 2015 Author Report Posted June 25, 2015 Next week I will be troubleshooting fuel components. Thanks again for everyone's help. I will keep you posted.
BassMan11 Posted June 29, 2015 Author Report Posted June 29, 2015 Hey Guys, Got out on the water this weekend and played around with the motor. After reading a few reports I saw someone say if you played around with the choke it might do something. I did that and immediatley the boat launched up to 20mph. Is this a carb / jet issue? At least I was up on plane with two people!
BillM Posted June 29, 2015 Report Posted June 29, 2015 Yup, something is clogged. My guess is old fuel was left in it.. Simple fix as well.
Fisherman Posted June 29, 2015 Report Posted June 29, 2015 If you're pulling out the choke and it's running faster, then you definitely have carb issues, the jets need a thorough cleaning. I just did a lawnmower for a lady a couple doors down, run for 2-3 seconds and quit, over and over. Pulled off the bowl and it was full of little gummed up gas balls. Took out the main jet, ran a very thin piece of copper wire through it and pushed out more jello gas. A little more cleaning, put it back together and it runs like new. She even said she used stabilizer regularly. I showed her the can of Seafoam for future use.
BassMan11 Posted June 29, 2015 Author Report Posted June 29, 2015 (edited) Thanks guys. I'll get my mechanic to look at it. I took it to a marina to have the carbs cleaned but I guess they weren't cleaned good enough? Paid a pretty penny for it as well. Makes me a little upset but at least the problem is diagnosed now and I can just get it fixed properly. Edited June 29, 2015 by BassMan11
BillM Posted June 29, 2015 Report Posted June 29, 2015 I'd go back and get them to do the job properly. I wouldn't pay for it again either, that's Bull.
Beavertail Posted June 29, 2015 Report Posted June 29, 2015 (edited) Paid a pretty penny for it as well. Makes me a little upset but at least the problem is diagnosed now and I can just get it fixed properly. Don't let them off the hook so easy, I would definitely go back and talk to them about it. I have limited experience dealing with marinas but so far they all have been serious let downs. Edited June 29, 2015 by Beavertail
MrSimon Posted June 29, 2015 Report Posted June 29, 2015 I agree. Don't let it go. Cleaning carbs isn't all that hard, but it's one of those jobs that people often don't do properly .... especially the jokers some marinas hire to work in the shop. If at all possible, take the boat out on the water and show them what's happening, then after the fix it, take them back out to make sure it's fixed. Also, I believe the carbs on that motor need to be synchronized ... which should have been included in the work they already did.
Sinker Posted June 30, 2015 Report Posted June 30, 2015 Have you given it a good dose of seafoam yet? I bet that will clear a lot of it out. S.
ecmilley Posted June 30, 2015 Report Posted June 30, 2015 3 carbs with all the same problem is unlikely pulling choke still makes most of fuel come through main jets. Be looking at fuel lines/connectors /pick up first then check fuel pump diaphragm
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