Low Top End GT40 |
Post Reply | Page <12 |
Author | |
TRBenj
Grand Poobah Joined: June-29-2005 Location: NWCT Status: Offline Points: 21171 |
Post Options
Thanks(0)
|
Prop down 1/2" and keep running it. I wouldn't touch it unless you really had the desire to do an engine rebuild. 43mph out of a 21' Sport does not seem out of family, especially since you are a little over propped.
|
|
63 Skier
Grand Poobah Joined: October-06-2006 Location: Concord, NH Status: Offline Points: 4269 |
Post Options
Thanks(0)
|
Agree completely. Paul, in an earlier post you said "I really have no issues with how the boat runs". You are really so close to expected performance for that boat that it's possible you could do a full rebuild and not see any difference. If you read the props threads you probably saw that these boats seem to vary by 2-3 mph with no obvious mechanical reasons for it. If you are trying snake oil, I'd put my vote in for Marvel Mystery Oil. Add a bit to the next few tanks of gas. Also, I don't know how much you get out on the boat but there is nothing better than skiing on it as much as you can, putting a load on it and putting hours on it, to clean up a very mild ring problem. I can't imagine with the compression numbers you listed that you have a cracked ring, seems more likely just some rust or cylinder wall scuffing. My usual disclaimer, I could very well be wrong! |
|
'63 American Skier - '98 Sport Nautique
|
|
Blamey
Gold Member Joined: August-18-2015 Location: White Plains,NY Status: Offline Points: 631 |
Post Options
Thanks(0)
|
Thanks Tim, I have some questions 1. When you say don't touch it, does that mean the snake oil too? I already have these so unless it's possible I'll cause harm, I'd like to try them. 2. Would a new prop be better for the engine or just give me better performance? Should i get a new prop if I don't need the performance gains. Ultimately, half the reason I bought the boat was to learn how to fix an engine. I'd really like to solve this problem even if it doesn't really need it, which I why I have these questions. Sounds like the best advice is to run the boat for a couple more seasons and wait to rebuild if things get worse. |
|
96 Super Sport
Previously: 95 Sport Nautique, 1980 Ski Supreme |
|
Blamey
Gold Member Joined: August-18-2015 Location: White Plains,NY Status: Offline Points: 631 |
Post Options
Thanks(0)
|
This is the advice I got last year when I bought the boat. This season I have done about 50 hours, 20 of which were wakeboarding without any change, hence me trying to go with the snake oil. I am mostly motivated to learn as much as possible. I have learnt so much this year thanks to this site. Mostly simple stuff but I knew nothing about it a year ago. I've change spark plugs, fuel filters, impellers, oil, Installed perfect pass, wet sanded and buffed gel coat. done gel coat repair, replaced relays and IACV, removed a stuck propeller, lapped a new prop, cleaned throttle body and spent loads of time with my family on the lake. It's been a great year and I guess I am just looking for some projects for the winter. I would like to rebuild the engine next year after I have bought a new house (hopefully with room to work on the boat). I was hoping there were some thing worth working on this winter to see if I could get things running a little better. |
|
96 Super Sport
Previously: 95 Sport Nautique, 1980 Ski Supreme |
|
75 Tique
Grand Poobah Joined: August-12-2004 Location: Seven Lakes, NC Status: Offline Points: 6127 |
Post Options
Thanks(0)
|
there is always another project that can be done. A boat is never really "done" |
|
_____________
“So, how was your weekend?” “Well, let me see…sun burn, stiff neck, screwed up back, assorted aches and pains….yup, my weekend was great, thanks for asking.” |
|
TRBenj
Grand Poobah Joined: June-29-2005 Location: NWCT Status: Offline Points: 21171 |
Post Options
Thanks(0)
|
Don't touch it, meaning don't touch it. No snake oil (ever).
Propping down will ease the load on the engine and return better performance. Win/win. |
|
75 Tique
Grand Poobah Joined: August-12-2004 Location: Seven Lakes, NC Status: Offline Points: 6127 |
Post Options
Thanks(0)
|
Tim, I had never heard of Restore until Pete posted the link. I was thinking, why not, what the heck. My engine might be a little tired and my compression, although OK isn't tops. But you are saying don't touch the stuff? |
|
_____________
“So, how was your weekend?” “Well, let me see…sun burn, stiff neck, screwed up back, assorted aches and pains….yup, my weekend was great, thanks for asking.” |
|
Blamey
Gold Member Joined: August-18-2015 Location: White Plains,NY Status: Offline Points: 631 |
Post Options
Thanks(0)
|
Any prop suggestions? ACME 1442? |
|
96 Super Sport
Previously: 95 Sport Nautique, 1980 Ski Supreme |
|
TRBenj
Grand Poobah Joined: June-29-2005 Location: NWCT Status: Offline Points: 21171 |
Post Options
Thanks(0)
|
I can think of all sorts of things that would be bad to run through an engine... Do you know exactly what is in that bottle?
Look at it the other way- what do you hope it will do? Is there any logical reason to think it will improve something? Smells like leprechaun farts mixed with unicorns and rainbows to me. |
|
TRBenj
Grand Poobah Joined: June-29-2005 Location: NWCT Status: Offline Points: 21171 |
Post Options
Thanks(0)
|
470, 1442 or 654 are all candidates with 15" pitch.
|
|
gun-driver
Grand Poobah Joined: July-18-2008 Location: Pittsburgh, Pa Status: Offline Points: 4127 |
Post Options
Thanks(0)
|
All your numbers are down by over 40 PSI + compared to mine so I would say a rebuild is your only option if your concerned about performance. If you not worried about performance then run it as is.
Restore may get you a little improvement but it's not going to cure it. DON'T CLEAN THE INTAKE with any type of cleaner you can damage the intake. I agree with Tim |
|
KENO
Grand Poobah Joined: June-06-2004 Location: United States Status: Offline Points: 11061 |
Post Options
Thanks(0)
|
From 63 Skier "Agree completely. Paul, in an earlier post you said "I really have no issues with how the boat runs". You are really so close to expected performance for that boat that it's possible you could do a full rebuild and not see any difference. If you read the props threads you probably saw that these boats seem to vary by 2-3 mph with no obvious mechanical reasons for it." After reading this thread, what I get out of it is that you're happy with the way the boat runs, had a lot of good family time in it it doesn't have any other issues you're new to working on engines (comments like attempting to replace a distributor cap and rotor make me think this) you're saving for a new house So like everybody says leave it alone and drive it. If you want to get some first hand experience find a dirt cheap (hundred bucks or so) junkyard engine like a 302 or 351. It doesn't need to run. And get a book on rebuilding a small block Ford. Get yourself an engine stand and have a blast taking it apart and doing plenty of hands on learning as you go. You might even want to put it back together again You gotta be careful though, things like this can get contagious and you'll be looking for more "projects" It's one thing to read about it and another to actually have all the pieces right in front of you. You'll figure out what tools to buy along the way and be much more comfortable when you decide to tear into the boat engine sometime in the future KenO |
|
Blamey
Gold Member Joined: August-18-2015 Location: White Plains,NY Status: Offline Points: 631 |
Post Options
Thanks(0)
|
Getting junkyard engine sounds like a great place to start and something I had thought about doing (i"d been looking at prices on craigslist a few weeks ago). I have the book already and was actually re-reading it this weekend. Thanks for the advice Ken. I'll put this on hold for now until I'm ready for a rebuild. In the mean time I'll see if I can find an old 351W. |
|
96 Super Sport
Previously: 95 Sport Nautique, 1980 Ski Supreme |
|
Post Reply | Page <12 |
Tweet
|
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |