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strad
10-07-2012, 11:01 AM
84 S & S. I just had it out for the first time Friday. Bought it after a sandbar accident, fixed it, etc. Fri was test drive day. Anyways, I noticed that the airguides are off from each other by about 3-4 mph indicated. Is that a normal occurrence? If not, where do I look for a problem? I also notice that one has a red/orange needle (the starboard one) and the other has a white needle. Did they come that way, or has one gauge been replaced?

When I bought it, one pitot was busted (was original style) and the other was the kind skidim sells. I replaced the busted one with another one from skidim, so my pitots match now.

EricB
10-07-2012, 11:25 AM
strad;
They are adjustable. Use a GPS to figure out which speedo is off and adjust them. Usually there is the small Allen screw sticking through the lower portion of glass to fine tune the speedometers. Also, it is best to target your normal speed when adjusting. If you ski at 32 mph, tune/match them at that speed.
If one has the orange needle and the other white, they are probaly different "vintages".

JimN
10-07-2012, 12:02 PM
84 S & S. I just had it out for the first time Friday. Bought it after a sandbar accident, fixed it, etc. Fri was test drive day. Anyways, I noticed that the airguides are off from each other by about 3-4 mph indicated. Is that a normal occurrence? If not, where do I look for a problem? I also notice that one has a red/orange needle (the starboard one) and the other has a white needle. Did they come that way, or has one gauge been replaced?

When I bought it, one pitot was busted (was original style) and the other was the kind skidim sells. I replaced the busted one with another one from skidim, so my pitots match now.

Your boat has a small vinyl line going from each pitot to its gauge, with a ballast at transon for each. If the ballast or line is clogged, or the line is pinched, it will read low. Blow compressed air into each line from the front and make sure it's cleared out. If one (probably the older one) is restricted, use a paper clip to clear the pitot by inserting it from the outside. It may have silt or vegetation in the passage. You could also swap the vinyl lines to the gauges- if the same one reads low, it eliminates the pitot and line from the equation.

mikeg205
10-07-2012, 09:56 PM
No need for speedo's anymore...all smart phones have free speedo GPS app. Unless of course you're boating in flyover country...

strad
10-08-2012, 12:24 AM
Hmm. Well I took it out for the second time today. Went for three runs with it, and on each one they read closer and closer to each other, until the last one they were reading almost identical. So maybe one was dirty and blew itself out.

mayo93prostar
10-08-2012, 07:57 AM
strad, you should still check them against a gps and adjust if needed. only adjust one to gps and then get the other to match the first one. also, never miss the opportunity to post a pic of that classic.

madcityskier
10-09-2012, 10:12 AM
My 85 has red needles. I had friends with 84's and theirs were white. It would stand to reason that they must have change over at some point, and if they had an odd number of gauges from the older batch... Your's may have been the changeover?
I would highly suggest getting them dialed in either by gps, or by setting based on times as you run through a slalom course. It's always nice to know that you're actually towing someone at the speed they want to be towed.

strad
10-09-2012, 10:52 AM
Haha well now that I've replaced the iphone that I drowned last weekend while loading the boat (thank God for Apple's Genius Bar replacement program), I'll try the GPS trick and see how far off the speedos are.

Besides the difference in needle colors, the speedos look exactly the same with regard to design, age, wear etc.

madcityskier
10-09-2012, 11:32 AM
That fits with the changeover theory. I will say that one end of our slalom course has a fair bit of weed growth which tends to clog speedos. I picked up a cell phone mount from bestbuy.com for like 6 bucks and put my phone on that with a good digital speedo app. Works great, but if you haven't added a 12v outlet for a charger somewher it will kill the battery fairly quickly. Another nice app is navionics if you're on water you're not highly familiar with. Lake map with depth chart and course tracking can be very useful to keep that prop nice and especially if you're retracing a long haul after dark on an unfamiliar body of water.

88 PS190
10-10-2012, 12:30 AM
Got 350$?

http://precisionstar.ca/?page_id=124

If 350 weren't starting to get closer to the ~1200$ a perfect pass digital pro goes for, I'd be tempted.

mikeg205
10-10-2012, 09:02 AM
This plus your smart phone trumps the $350... :) - That GPS Speed should be priced a tad above the Faria - then they would sell a bunch...

http://www.gandermountain.com/modperl/product/details.cgi?pdesc=Dry-Pak-Floating-Waterproof-GPS/PDA/Smart-Phone-Case&i=72601&r=view&aID=506G7H&cvsfa=2586&cvsfe=2&cvsfhu=3732363031&s_kwcid=goobasecontent_goobasecontent_filler&cID=GSHOP_72601

Sodar
10-10-2012, 10:37 AM
Got 350$?

http://precisionstar.ca/?page_id=124

If 350 weren't starting to get closer to the ~1200$ a perfect pass digital pro goes for, I'd be tempted.

That is double what a GPS speedo from gaffrig or livorsi. I wonder if they have to be more precise than just a GPS speedo. Do they also take input from a paddle wheel like StarGazer does?