Johsnon 175 Motor Question

[beckleybassfanatic]

I have a 2004 Stratos 285 Magnum (ProXL) with a 175 Johnson (J175GLSRM)...I have been on here several times asking questions about this, but still having issues...I am running a 24P Raker that has just been worked by Mark Croxton, 10 inch Pro-HiJacker jack plate, Hot-Foot, right now Im at 2 5/8" Below Pad...I have new Champion plugs in it gapped correctly, also de-carbed the motor this year, checked motor compression, around 95-100 on all cylinders...I still cant turn but 5100 RPMs, and only get 62.8 GPS...Almost everybody I talk to tells me my motor needs to be turning 5500-5600 RPMs, the motor simply wont do it, except when I go to a 23P Prop, but then I lose speed...Is there anything else simple that could make me be losing power?...I also cleaned the fuel filter this year....It just makes me think that Im not making full HP...The motor sounds strong when running...Ive got guys here running 285s with 150s and there burning me down the lake...Please Help!!!

[ChampioNman]

Timing needs to be checked, and throttle plates need to be verified they are opening fully at WOT and that the timing is at the proper * at WOT. If you have everything but the kitchen sink in the boat that makes a difference to. The 285 is weight sensitive and needs to have the bow up and on the pad to make it run. Can't have a couple of 300 pound biscuit eaters and make it fly. As the boat sits now take it to a set of truck scales and weigh it with you in it and your partner too. Then take it home empty everything out of it and go back to the scales with you and your bud. The difference is how much stuff you have inside of it. Run it empty with you, your bud and safety gear on. See how much difference it makes. Strange as it sounds you may have too much setback.

[DanCard]

Agree with above poster. You may have too much set back. 6" plate would probably be best on that boat, 8" at the most. But 6" is probably where it needs to be. My 175 was turning 5850 RPM on my Javelin with a 24 raker. Put a 5.5" plate on it and ran a 26 Raker II, it turns 5400 RPM and im running 66.2 mph with a load and my partner.

[beckleybassfanatic]

I just installed the 10 inch plate maybe 3 months ago....I had a 6 inch Slidemaster before it....The only thing I gained from the "10 inch jackplate" was maybe 50 RPMs and it felt like the bow was lifted more...I do believe that the speed stayed the same...BUT, after Mark reworked my prop, I gained close to 100 RPMs and a little over 2 MPH...I am gonna check the timing, Is this something I can do??? these local boat dealers are a joke at times....My only reason for installing the 10 inch plate was because some people were telling me that the more setback you have, the more the bow is out of the water...I wish I didnt have a full time job and was rich, I'd get this thing figured out,

[ChampioNman]

If I'm not mistaken the maximum setback Stratos recommends is 8" or it will void the warranty of the hull. Power band for your motor is 4500-5500 and the HP is rated at 5000 RPm

[beckleybassfanatic]

Sorry if I sound stupid, what does "power band" mean? Is there any way of me checking the timing myself on my motor?

[ChampioNman]

Sorry should have said operating range. Yes you can check it with a timing light, a test wheel (prop) and an assistant to apply WOT.

[beckleybassfanatic]

Ok, I understand everything I need...But have never used a timing light, I'v seen them used on vehicles...what would be the correct timing?...Does my motor need to be in gear when using the light?...how does the light work?....how would I adjust the timing if its off?....sorry for all the questions...

[SEAHORSE]

Using a timing light around moving machinery is inherently dangerous, so because of the questions you asked, it would be best for you to enlist the services of a professional.

[Frank A]

suggest while he's check timing have him check rpms with a diag tach----you 62.8 sound like great speed for you hull and equip. mine runs 5600 rpm with just me and 20 gallons of fuel and my fishing gear tops out at about the same speed 62.1 gps and with 250 more lbs added it falls to 58.7 gps turning 5400 rpms.
3 or 4 hunderd rpms could be just tach reading off on an old tach.
LIKE MINE ..YOU RIG WILL ONLY GO 70MPH ON ITS' TRAILER..

[StratosDadRI]

I agree with Frank if your realy doing 62.6 GPS? that 5100 rpm for a 24 raker is very low. Again if you are realy doing 62.8 the math doesnt add up. That speed with a 24 Raker puts your motor at 5350-5500 rpms. What concerns me even more is that you claim all the 150 are flying past you. 99% of 18 Stratos's with 150's will never be a 65+boat loaded to fish.

Is there anyway that 62.8 GPS is inaccurate mph? cause that would make much more sense that your only tunring 5100 and all the other 150 are passing you.

Sound to me your more in the 55mph range and that would explain alot.

I have a 18 stratos with a 150 and its a 64 mph boat real light, its a 59 mph boat on tournament morning. I have run 2 Renagades ( 1 B& B ) by Mark, 24 & 22 Rakers, 24 Tempest, 24 Fury, 23 Tempest and a Shooter. No jackplate, 6" Jackplate and now a 8" Jackplate. 5" below pad to 2" below.

Hope this helps

[beckleybassfanatic]

I think my GPS is correct...only because I've ran beside of somebody that also had a GPS and was telling me they were doing around 62mph...Now the tachometer could be an issue, maybe set on the wrong pole,but what should the pole be set on.. I sorta exagerated when saying "all" 150s' are running past me...but there is a couple...Do you think my 10" Jackplate is to much?...

[Frank A]

I went from no jack plate severalyears age to a 8 in now the same 24 raker will break loose so much I had to JB weld the holes and drill them out to 3/8 and then send the prop to have recupped. now hawls but with just me but will loose bow lift with the 2nd person and their gear. Thinking of sending my prop to Mark having it repitched to a 23 and have him change the rake and add a ton of cup to the blade tips to hold the bow up while under a load. If I had to do it again Id proble stay with a 4 in 6 max on our hulls
Good Luck!

[Frank A]

just ran the numbers on prop slip calc
5100rpms with yu 1.86 gear ratio with ZERO SLIP (which is impossible) would put u around 62 mph
but if tach 5100 rpm and gps reading your statine to run 62.8 you would have -1 prop slip
but with a really great prop with only 8% slip @ 5100 you'd be right on 57 gps.
Think Id Get my tach checked and then look under the cowling on those 150hps that s blowing you out of the water.

[beckleybassfanatic]

Found out that my tach was on the wrong setting...needs to be on 5, it was set on 6...so I put it on 5...hopefully thats why Im showing only 5100 RPMs....these dealers around here are horrible...they supposedly pre-set the tach before I installed....

[Bassmeister]

All the rudes I've seen were set on 6.....

[ChampioNman]

6 is the correct number unless your tach manufacturer says otherwise.

[beckleybassfanatic]

According to Farias website it says 5....I hope!!!

[ChampioNman]

Faria site says 6. http://faria-instruments.com/s...u.pdf 12 pole alternator so the setting would be 6.

[316jughead]

OK Carlos, how about slowing down here a little bit. Did you do any of the things that ChamioNman suggested in his first post? As Seahorse said I would find a good Dealer with a dyno and have him check out your motor, he could tell you if your motor is putting out the HP it should. These two guy's know what they are talking about.