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viabill
06-28-2006, 09:44 AM
I recently bought an '89 Barefoot 190 with the 454HO engine. THe boat has 280 hours and the rudder has a cavitation burn on the upper right (looking at it from the rear) side that is over 1/4" deep. Is this a common occurrence with some boats? Should I expect to have to replace the rudder every 300 hrs?

bigmac
06-28-2006, 10:00 AM
I recently bought an '89 Barefoot 190 with the 454HO engine. THe boat has 280 hours and the rudder has a cavitation burn on the upper right (looking at it from the rear) side that is over 1/4" deep. Is this a common occurrence with some boats? Should I expect to have to replace the rudder every 300 hrs?

I had this kind of conversation with my propeller guy a couple of weeks ago. On inboards, the interplay between propeller and rudder is complex, but he tells me it's mostly a function of propeller geometry. He showed me a Ski Nautique he had in the shop with a serious cavitation burn on the hull between the prop and rudder, and he strongly contends that such burns on the hull or rudder are mainly due to a prop thats out of spec, badly designed, or simply the wrong prop for the boat.

His trick is to custom tune the prop. He paints the prop blades with mechanic's paint, puts it back on the boat and runs it. He will then periodically check the prop for the areas where the paint is NOT wearing off and says that represents an area where there is inefficient prop blade flow and therefore a clear source of cavitation. He grinds that part away, which he says will fix the problem.

If I were you, I'd consider getting some mechanic's paint and paint your prop blades. According to this guy (Mike, at Precision Propeller Works (http://www.brainerdguide.com/boats_props/repair.htm) , this will give you a lot of information about how your propeller is working on your particular boat. Mike's a great guy, and will talk your arm off about propellers. I'm confident he'd be happy to discuss your situation with you if you want to give him a call.

Cloaked
06-28-2006, 10:00 AM
I recently bought an '89 Barefoot 190 with the 454HO engine. THe boat has 280 hours and the rudder has a cavitation burn on the upper right (looking at it from the rear) side that is over 1/4" deep. Is this a common occurrence with some boats? Should I expect to have to replace the rudder every 300 hrs?I have never seen any burn on the rudder from cavitation.

Honestly, this makes no sense to me, but I may not clearly understand you're point.

Sounds like a side-grinder gone wild with a 1/4" gouge in the nibral rudder. :eek:

Cloaked
06-28-2006, 10:05 AM
I had this kind of conversation with my propeller guy a couple of weeks ago. On inboards, the interplay between propeller and rudder is complex, but he tells me it's mostly a function of propeller geometry. He showed me a Ski Nautique he had in the shop with a serious cavitation burn on the hull between the prop and rudder, and he strongly contends that such burns on the hull or rudder are mainly due to a prop thats out of spec, badly designed, or simply the wrong prop for the boat.

His trick is to custom tune the prop. He paints the prop blades with mechanic's paint, puts it back on the boat and runs it. He will then periodically check the prop for the areas where the paint is NOT wearing off and says that represents an area where there is inefficient prop blade flow and therefore a clear source of cavitation. He grinds that part away, which he says will fix the problem.

If I were you, I'd consider getting some mechanic's paint and paint your prop blades. According to this guy (Mike, at Precision Propeller Works (http://www.brainerdguide.com/boats_props/repair.htm) , this will give you a lot of information about how your propeller is working on your particular boat. Mike's a great guy, and will talk your arm off about propellers. I'm confident he'd be happy to discuss your situation with you if you want to give him a call.Hmmmmmmmmmm.....

Not to dispute anything I know little or nothing about but this is a bit extreme for me to clearly grasp. I'd have to ask right away, why not put the correct prop on the boat and eliminate all of this underwater-galactic fine tuning and spray painting?

bigmac
06-28-2006, 10:28 AM
Hmmmmmmmmmm.....

Not to dispute anything I know little or nothing about but this is a bit extreme for me to clearly grasp. I'd have to ask right away, why not put the correct prop on the boat and eliminate all of this underwater-galactic fine tuning and spray painting?

Obviously, cavitation burns are far less likely on an outboard or I/O, but on an inboard, the prop wash goes from the prop back along the hull and across the rudder. If the prop is putting out a stream of bubbles (cavitation), THAT will cause cavitation burn. The most likely source is a ding on the prop (which mechanics paint will point out). But it might be that the prop flow hits the hull or the rudder in a certain way that ALSO creates that stream of bubbles, or it might be there's a ding on the hull, or on the rudder that's doing that too.

All of these inboard manufacturers redesign their hulls rather frequently, but the prop that the boat manufacturer puts on there is an off-the-shelf Acme (some mfgrs use OJ). IIUC, the boat manufacturer selects a prop for appropriate RPM at WOT using the best/cheapest prop available from their selected manufacturer, but they're constrained by what props are available from that prop maker. In point of that, I note that the stock prop that came on my 230VRS was an OJ 14x18. I replaced it with an Acme 847 and have better acceleration, better top speed (by 1.5-2 mph), and less cavitation. Since cavitation problems may take time to show themselves, the boat maker has no immediate way of knowing if that particular prop will create some kind of flow issue that results in cavitation across the hull or rudder - they can only look at performance (WOT and acceleration).

In other words, the boat maker may have several reasons for not being able to put the correct prop on the boat - mostly, I suspect that they can't afford to test and have a prop custom made for every boat model they make - they have to take what's available.

east tx skier
06-28-2006, 10:57 AM
Hmmmmmmmmmm.....

Not to dispute anything I know little or nothing about but this is a bit extreme for me to clearly grasp. I'd have to ask right away, why not put the correct prop on the boat and eliminate all of this underwater-galactic fine tuning and spray painting?

Propellers are never perfect. My hunch is that the propeller on his older boat is hand finished. It was not uncommon to get a hand finished prop NIB that had some flaws to it. I think BigMac is assuming that he has the recommended prop on there as far as size/pitch goes.

bigmac
06-28-2006, 11:03 AM
Propellers are never perfect. My hunch is that the propeller on his older boat is hand finished. It was not uncommon to get a hand finished prop NIB that had some flaws to it. I think BigMac is assuming that he has the recommended prop on there as far as size/pitch goes.

Yeah - based on my limited knowledge, imparted to me by a (IMHO) real smart guy who's living is propellers, I suspect that viabill's cavitation burn is either a small ding in the prop, or a small ding in the part of the rudder just forward of the gouge he mentioned.

viabill
06-28-2006, 07:54 PM
Thanks for the inputs, guys. I'm going to take some pictures of the rudder and post them so you can see what I'm talking about. It's pretty strange!
For now, I'm attributing it to something bigmac mentioned about the mfgr not having the time or resources to choose the best prop.
If I'm not mistaken, MC put this 425 HP/ 500 ft lb engine in these boats without making any real changes to the hull or rudder designs to accomodate it. The prop looks like it is original, and is a 4-blade stainless version. Another twist is that the prevoius owner had a ballast bag in te boat and was trying to wakeboard behind it. I suspect the attitude of the boat while pulling was much more bow-up than MC intended, and the prop was slipping more than it normally would with skiers in tow. Maybe these factors could cause what I'm seeing.

TMCNo1
06-28-2006, 09:23 PM
In other words, the boat maker may have several reasons for not being able to put the correct prop on the boat - mostly, I suspect that they can't afford to test and have a prop custom made for every boat model they make - they have to take what's available.[/QUOTE]


You should see the pallets of experimental props in boxes that Mastercraft has built up over the years, that MC has had made special for all the boats they have built. The prop manufacturers are always working with boat builders in this manner for their business. The R&D department is always trying out new ideas and combinations to provide the best all around performance in the boats they design for sale. The most amazing thing is, most if not all of these props that were not acceptable for use are then sold to a scrap dealer or given back to the prop manufacturer to melt down and recycle into other props.

Why do OB's and I/O's have sacrifical zinc anodes on the engines and lower units? Electrolysis! Why do most inboards other than salt water boats not have them. Any boat powered by a engine using electrical current as part of its function releases static electricity into the water to ground while running and this causes the softest metal in the water that has a direct ground to the engine to eat away at that metal. In OB's and I/O's the softest metal in the water is the engine or outdrive of aluminum, therefore a softer metal to be exposed is the sacrifical zinc anodes that they install on the transom and on the adjustable tab above the prop and have to be replaced over time. On an inboard the softest metal with a direct ground to the engine is the prop, which in turn discharges the static electricity to the rudder thru the water and then into the water causing the rudder to burn or eat away because it is softer [brass] than the prop [nickel/brass/aluminum alloy] or S/S which is harder. You may even see some erosion of the prop blades near the hub, but that is usually caused by cavatation and maybe some very small amount of electrolysis. The strut does not erode because it is isolated from the shaft by the bushings plastic surfaces and even though the steering cable is attached to the strut it is not attached directly to the electrical system via a ground. The New Saltwater Series boats that MasterCraft builds has sacraficial zinc anodes on the S/S Swim platform brackets and the shafts because salt water has a higher erosion factor because of the salt and electrolysis.
This was explained to me by a Mercury/Mercruiser engineeer several years ago at a boat show and in numerous article in magazines published throughout the marine industry.

JohnnyB
06-28-2006, 09:28 PM
Never seen a cavitation burn....can you post a pic?

TMCNo1
06-29-2006, 01:04 PM
No picture, but it looks like someone has sandblasted a spot on the starboard side of the rudder about 1.5" in dia. about 1.5" down from the top of the rudder, with coarse sand and spots can occur in the thick meaty part of the prop blade close to the hub on the rudder side of the blade about the same size. The prop spots are really noticable on OB or I/O aluminum props, where it has eat away the black factory paint, more so from cavatation than electrolysis.

jeverett
06-29-2006, 03:07 PM
Sounds to me like someone tryied to put some pull in the steering by grinding said rudder on the right side and didn't know what the HE#@ they were doing?????

Hoff1
06-29-2006, 03:53 PM
my rudder on my 1990 shows some cavitation signs with the pits in it. Prop is original, don't have a clue if it's sized right, or if it causes excessive vibration, or noise or caviation. But it keeps me going. :steering:

Probably should upgrade, but just cheap and lazy I guess.

viabill
06-30-2006, 09:15 AM
Here are a few pics of this rudder erosion. It looks just like TMCNo1 described.

You can't really see it, but in one place, you can see light from one side through to the other side.

SkiDog
06-30-2006, 10:11 AM
In other words, the boat maker may have several reasons for not being able to put the correct prop on the boat - mostly, I suspect that they can't afford to test and have a prop custom made for every boat model they make - they have to take what's available.


You should see the pallets of experimental props in boxes that Mastercraft has built up over the years, that MC has had made special for all the boats they have built. The prop manufacturers are always working with boat builders in this manner for their business. The R&D department is always trying out new ideas and combinations to provide the best all around performance in the boats they design for sale. The most amazing thing is, most if not all of these props that were not acceptable for use are then sold to a scrap dealer or given back to the prop manufacturer to melt down and recycle into other props.

Why do OB's and I/O's have sacrifical zinc anodes on the engines and lower units? Electrolysis! Why do most inboards other than salt water boats not have them. Any boat powered by a engine using electrical current as part of its function releases static electricity into the water to ground while running and this causes the softest metal in the water that has a direct ground to the engine to eat away at that metal. In OB's and I/O's the softest metal in the water is the engine or outdrive of aluminum, therefore a softer metal to be exposed is the sacrifical zinc anodes that they install on the transom and on the adjustable tab above the prop and have to be replaced over time. On an inboard the softest metal with a direct ground to the engine is the prop, which in turn discharges the static electricity to the rudder thru the water and then into the water causing the rudder to burn or eat away because it is softer [brass] than the prop [nickel/brass/aluminum alloy] or S/S which is harder. You may even see some erosion of the prop blades near the hub, but that is usually caused by cavatation and maybe some very small amount of electrolysis. The strut does not erode because it is isolated from the shaft by the bushings plastic surfaces and even though the steering cable is attached to the strut it is not attached directly to the electrical system via a ground. The New Saltwater Series boats that MasterCraft builds has sacraficial zinc anodes on the S/S Swim platform brackets and the shafts because salt water has a higher erosion factor because of the salt and electrolysis.
This was explained to me by a Mercury/Mercruiser engineeer several years ago at a boat show and in numerous article in magazines published throughout the marine industry.[/QUOTE]

Harold, I didn't know you knew so many BIG words!!!!!!!

Hoff1
06-30-2006, 10:42 AM
Here are a few pics of this rudder erosion. It looks just like TMCNo1 described.

You can't really see it, but in one place, you can see light from one side through to the other side.


My rudder has pits similar to the 3rd picture, but nothing as severe as the 1st picture. I have about 700 hours on mine for reference. Yours only having that amount in less than 300 hours does seem severe.

TMCNo1
06-30-2006, 11:01 AM
You should see the pallets of experimental props in boxes that Mastercraft has built up over the years, that MC has had made special for all the boats they have built. The prop manufacturers are always working with boat builders in this manner for their business. The R&D department is always trying out new ideas and combinations to provide the best all around performance in the boats they design for sale. The most amazing thing is, most if not all of these props that were not acceptable for use are then sold to a scrap dealer or given back to the prop manufacturer to melt down and recycle into other props.

Why do OB's and I/O's have sacrifical zinc anodes on the engines and lower units? Electrolysis! Why do most inboards other than salt water boats not have them. Any boat powered by a engine using electrical current as part of its function releases static electricity into the water to ground while running and this causes the softest metal in the water that has a direct ground to the engine to eat away at that metal. In OB's and I/O's the softest metal in the water is the engine or outdrive of aluminum, therefore a softer metal to be exposed is the sacrifical zinc anodes that they install on the transom and on the adjustable tab above the prop and have to be replaced over time. On an inboard the softest metal with a direct ground to the engine is the prop, which in turn discharges the static electricity to the rudder thru the water and then into the water causing the rudder to burn or eat away because it is softer [brass] than the prop [nickel/brass/aluminum alloy] or S/S which is harder. You may even see some erosion of the prop blades near the hub, but that is usually caused by cavatation and maybe some very small amount of electrolysis. The strut does not erode because it is isolated from the shaft by the bushings plastic surfaces and even though the steering cable is attached to the strut it is not attached directly to the electrical system via a ground. The New Saltwater Series boats that MasterCraft builds has sacraficial zinc anodes on the S/S Swim platform brackets and the shafts because salt water has a higher erosion factor because of the salt and electrolysis.
This was explained to me by a Mercury/Mercruiser engineeer several years ago at a boat show and in numerous article in magazines published throughout the marine industry.

Harold, I didn't know you knew so many BIG words!!!!!!![/QUOTE]


I'm not as good as I once wuz, but I'm as good once as I ever wuz! :eek:
Like you Skidog, there are somethangs you just don't ferget! :rolleyes:

TMCNo1
06-30-2006, 11:14 AM
Here are a few pics of this rudder erosion. It looks just like TMCNo1 described.

You can't really see it, but in one place, you can see light from one side through to the other side.

Dude, get that rudder replaced!!!!!!!!!!!!!!!!
I've never seen erosion that bad before and does look like a cavitation problem, especially on the back starboard side of the rudder behind the thick part. My original rudder eroded like that on the front starboard side, but only after I ran a polished and chromed 3 blade for 8 years. The original factory finish or polished prop did not erode the rudder. The port side looks like casting imperfections that weren't ground away when the rudder was made, as original rudder had marks like that new and it took forever to grind them out to polish the rudder.
My original rudder cracked 2 years ago about 1.5": down from the top on the starboard side in the thick part where the S/S shaft is cast into the bronze blade. I guess too much grinding and polishing in that area where the erosion was occuring, so I wasted no time in replacing the rudder!

viabill
06-30-2006, 01:21 PM
TMCNo1
I agree. In fact, I had ordered a new one and I picked it up today. I thought about smoothing it out, since they are pretty rough with lots of heavy grind marks as they come from the MC dealer. Will smoothing it out help to minimize the erosion?

I'm still really interrested in talking to someone who has experience with the Barefoot 190 to see how much erosion they have seen over the years. and if they changed props to help the situation.

viaBill

TMCNo1
06-30-2006, 01:26 PM
TMCNo1
I agree. In fact, I had ordered a new one and I picked it up today. I thought about smoothing it out, since they are pretty rough with lots of heavy grind marks as they come from the MC dealer. Will smoothing it out help to minimize the erosion?

viaBill

Good call on the new rudder!
No, slicking up the rudder and even polishing it won't help prevent the burn, but it sure makes it PURRDY!!!!!!!!!!!!
Is the prop that you have on there now, the same one you have always run or is it fairly new. Looks like a S/S. That kind of burn and damage on a rudder takes several hard years of use to show up. If erosion or burn starts appearing on the new rudder real soon, I would recommend changing props to see what happens and it doesn't hurt to have a spare prop if you don't have one. There just may be a problem with the prop causing the erosion that severe. Talk to Eric @ OJ or Bill Weeks @ ACME for their recommendatios for your application.
I assume the '89 Barefoot 190 you have is the TriStar, with the 454C.I. and that situation may just be the nature of the beast as there are very few of those boats around! IMO

Farmer Ted
07-03-2006, 11:43 AM
some info on prop cavitation

xsvfooter
08-01-2006, 06:34 PM
I have a 1990 version in open bow. The rudder showed the exact cavitation burn. The first thing you need to do is pitch that oem prop. It's a really small SS four blade that requires a brass hub adapter. If you lose that hub adapter...your toast. I heard you can't buy it anymore. I bought the boat with 165hrs on it and replaced the rudder and prop within 200hrs. Running a different prop for over 360 hours (560 total on the boat) I have some cavitation burn, but nothing like I was getting with the OEM prop.

I have two other props that I run.
The first is an OJ Force 4 13x14 four blade. I had OJ add additional cup to bring my RPM's down. The boat handles great and gets great hole shot. I foot a lot and the table is nice and soft with that prop. I have no problem deep water starting 4 footers (lots of banging obviously). It still rev's around 5300, higher than I'd like to see. Con - not a great big lake cruising prop. I have to run it pretty hard to cruise at a reasonable speed. That causes the 454 to eat lots of gas.

I just bought an ACME 431 13x13. I spent a week on Table Rock Lake in MO running this prop. It's silky smooth. Hole shot doesn't feel quite as strong (nothing scientific so it may actually be the same), but I don't have to run it as hard to cruise. I burned alot less gas with this prop. I think I have more top end, but I didn't use GPS to compare. I can still over rev it in the 5300 range. One additional benefit, it seemed to handle rough water better. I think to boat has a tendancy to ride higher in the water which might aid in the rough water ride. A con is it seemed to slightly porpoise with a heavy towing load (84" multi rider tube) when below slalom speeds with this prop. It may have just been some rollers, not 100% sure it was an actual porpoise.

All that being said, I'm keeping the ACME and it will be my lake prop. I mostly ski in a shallow river and don't go great distances so I use the OJ on the river. The down side to both props are they are Nibral. The river I ski in is extremely shallow. Never any large boulder strikes, but sand and gravel skims do occur. The Nibral just doesn't hold up to minor taps. I'm looking for a SS prop for the river since getting the OJ tuned up 1-2 times per summer is getting expensive. Anybody have any experience with the SS cutter?

viabill
08-01-2006, 09:03 PM
xsvfooter- It's great to hear from someone who actually has another B/F 190. I'm going to take your advice and change over to the ACME. It looks like I have another issue to fix, also. My 190 tops out at about 4200 RPM @ 45 mph, but it should turn 5000 to 5300 RPM, as your does. I attributed the low RPM to the odd-ball prop that I thought was aftermarket, but now that I know it's OEM, I likely need a tune-up or something.

xsvfooter
08-02-2006, 11:49 AM
You should be getting way more than 4500 RPMs. My engine is extremely strong and I'm always concerned with over reving. I like to keep it below 5200, but depending on which prop and condition of the prop I touch 5400 at WOT. With the ACME 431, I'm pretty sure I touching at least 50mph, likely 52ish.

I've had this boat since 98 and have lots of lessons learned. Another upgrade was replacing the standard ignition with breakerless. I actually bought the whole distributor assembly. ($173 at the time from dim) Quite easy, just pull the old distributor out, drop in the new one, and time it.

I had a winterization brain cramp two years ago that caused a cracked block. After opening the petcock, I didn't poke it with a hanger. Sand in the petcock caused water to stay in it. I created a temporary closed cooling system to run Moroso Ceramic Seal through the block. It sealed the crack and I ran an entire summer on the motor. I was just fearful it would let loose at a bad moment. Last winter I had the motor rebuilt with a new block. Since I had the motor out I also replaced the carpet. The new motor runs great, but I now have a slight leak at the rear main seal. Not a major repair in terms of part cost, but I do need to pull the motor out this winter to replace the seal.

Are you getting a nice blue puff of smoke when you start it after the engine has been running? The valve stem guides on the heads aren't nurled down to allow for rubber valve stem seals. I had the valve stem guides cut down on the heads to allow clearance for the rubber seals when I had the new block built. No more blue puff. It's not worth doing if your not having any other work done.

viabill
08-03-2006, 08:38 AM
More good input, xvs. I'm going to check out the RPM situation this weekend. What kind of Elect distributor did you get? The guys at Indmar told me thay have a kit that includes a GM dist., wires, etc. that is a drop-in for ~$375.
No valve seal smoke, yet, but I do get black smoke from a rich condition when starting the engine after the engine is thoroughly warmed up and we're doing lots of stop & start with changing skiers, etc. My only thought is to change both needle & seats in the Holley. Have you had any carb issues?
Did you have any trouble finding a replacement block? I understand these are 4-bolt main blocks and finding a MarkIV (old) performance block could be difficult and would be pricey.

TMCNo1
08-03-2006, 12:06 PM
[QUOTE=viabill]
. The prop looks like it is original, and is a 4-blade stainless version. QUOTE]


Just caught this statement, and a 4 Blade S/S prop should not have been original on a '89 Barefoot 190 454HO!
Do you have a owners manual and what does it say in it as far as the prop it came with. My '89 PS190 manual tells me what prop my boat came with and in my manual it also has the specs. for your boat too, 454CI, 340hp and 425hp both had a 14X14 cupped 3 Blade.

TMCNo1
08-03-2006, 12:13 PM
More good input, xvs. I'm going to check out the RPM situation this weekend. What kind of Elect distributor did you get? The guys at Indmar told me thay have a kit that includes a GM dist., wires, etc. that is a drop-in for ~$375.
No valve seal smoke, yet, but I do get black smoke from a rich condition when starting the engine after the engine is thoroughly warmed up and we're doing lots of stop & start with changing skiers, etc. My only thought is to change both needle & seats in the Holley. Have you had any carb issues?
Did you have any trouble finding a replacement block? I understand these are 4-bolt main blocks and finding a MarkIV (old) performance block could be difficult and would be pricey.


All you need is a Electronic Ignition Converson Kit from Skidim for around$100, fairly simple, follow instructions and you may need a coil too.

xsvfooter
08-03-2006, 12:45 PM
TMCNo1, those were my thoughts initially. I was so unhappy with the prop I had on it I called MC to find out what the oem prop should be so I could put one on. I was stunned when they told me the 4 blade stainless was it. No body could tell me who made the prop or much about it (diameter or pitch). I had a local prop shop, Airmarine out of Chicago, tell me they thought it was done my Michigan Wheel. They also told me to guard the brass insert with my life since it can't be ordered anyplace.

Regarding the distributor, its a GM from discount inboard marine. Their part number back in 4/98 was prs44-879 and cost was 173.50.

Regarding the carb, while the engine was being rebuilt I used a holley refresh kit and rebuilt the card. It's actually an easy carb to work on. Just follow the directions in the kit. The powervalve in the kit was not the same size that was in the carb, but I used it anyway. I didn't have any hesitation issues after the rebuild, so I just continued to use the new PV even though it was different than the original. I used a vacuum gauge to tune the carb and the motor runs flawless. The electric choke is broke, but the engine warms up so fast it's not a big deal.

Most prebuilt marine BB rebuilds offered from engine rebuilders are low HP (300 ish) and a two bolt main. None of them had a short block I could drop in, so I opted to have a local shop do the work. The guy who owns the shop races boats, so he has lots of experience with marine motors. Regarding getting the 4bolt Gen IV big block, yes they are difficult to find. Not impossible, but just not real common. You'll also find that the hot rodders love the heads from that engine. I seriously thought about going to a new generation BB and heads. I don't remember the exact amount, but selling the heads would have offset a lot of the expense. As it turned out, I spent $2470 getting it rebuilt. List of services: rebore .030 over, align bore, rods reconditioned, cylinders hones, polished crank, block resurface, magnaflux block, valve job, heads refaced, magnaflux heads, cut for seals (I may have missed a few). List of parts: block, pistons (speed pro forged), rings, bearings (main, rod & cam), wrist pins, gaskets, lifters, oil pump, valve st seals, freeze plug, spring shims.

Moral of the story - remove the petcocks and put plug in so your not tempted to just open them. When you remove the plugs, poke the holes in case there is sand in there.

TMCNo1
08-03-2006, 01:09 PM
Most props have the Manufacturer, size [dia./pitch], rotation, cup or not and date of mfg. stamped on the hub, between the blades. My original '89 is a Federal Propellor.

TMCNo1
08-03-2006, 01:25 PM
Somewhat of a double post, but,..............
On our '89, the original is a Federal, SuperCup, Equi-Poise, 13LH13, Ni-Bral, 5-88, stamped on the hub between the blades and a "S" stamped on the hub face behind the prop nut. FWIW, Look for the info. on it.

viabill
09-11-2006, 02:21 PM
I thought I would post an update on my Barefoot 190 progress, since your collective advice was instrumental in helping me find my lost horsepower.

I took xsv's advice on the carb and distributor improvements, and found some interesting things.
The carb had two major flaws, and the distributor wasn't advancing the spark nearly enough.

First, the small tab that holds the check ball for the accel pump was never peened in place correctly and had fallen out, thus the story I was told that "you have to pump the gas 16 times to start it cold".

Next, I noticed that the jets for the primary side appeared much larger than I would have expected for that size carb. They were 84's. So I checked the secondary jets and they were 76's. After much searching on the web, I found a listing that showed that the jets were reversed!!

Last, I checked the centrifugal advance of the Prestolite distributor with a timing light and found that I was only getting 12 degrees. Adding the initial 10 degrees advance to that, the engine was only seeing 22 degrees total advance, and it should have had about 36. I bought an MSD marine ready-to-run distributor and dropped it in after changing the springs to the correct ones, and got 34 degrees total advance with 10 deg. initial setting.

With all of these fixes in place, we took it to the lake last Sat, and couldn't believe the improvement!! The speedometer now pegs out at 50+, and the RPMs go over 4500. I'll use GPS to check the speed next week, but I'm sure it will hit about 53. That should be enough for the 'footers who always need more speed.

All I have left to do is change the prop (yes, it's the original small 4-blade SS prop with the goofy brass insert) to a 3-blade, since it appears that my rudder burn is reappearing. I can feel some roughness in the same area where the burn was most intense before, and we have only put about 40 hours on the new rudder. It looks like the ACME 13x14 or similar would be a good choice.

I'll let you guys know how that goes, but in the mean time, thanks for your wise advice!!

TMCNo1
09-11-2006, 02:26 PM
I thought I would post an update on my Barefoot 190 progress, since your collective advice was instrumental in helping me find my lost horsepower.

I took xsv's advice on the carb and distributor improvements, and found some interesting things.
The carb had two major flaws, and the distributor wasn't advancing the spark nearly enough.

First, the small tab that holds the check ball for the accel pump was never peened in place correctly and had fallen out, thus the story I was told that "you have to pump the gas 16 times to start it cold".

Next, I noticed that the jets for the primary side appeared much larger than I would have expected for that size carb. They were 84's. So I checked the secondary jets and they were 76's. After much searching on the web, I found a listing that showed that the jets were reversed!!

Last, I checked the centrifugal advance of the Prestolite distributor with a timing light and found that I was only getting 12 degrees. Adding the initial 10 degrees advance to that, the engine was only seeing 22 degrees total advance, and it should have had about 36. I bought an MSD marine ready-to-run distributor and dropped it in after changing the springs to the correct ones, and got 34 degrees total advance with 10 deg. initial setting.

With all of these fixes in place, we took it to the lake last Sat, and couldn't believe the improvement!! The speedometer now pegs out at 50+, and the RPMs go over 4500. I'll use GPS to check the speed next week, but I'm sure it will hit about 53. That should be enough for the 'footers who always need more speed.

All I have left to do is change the prop (yes, it's the original small 4-blade SS prop with the goofy brass insert) to a 3-blade, since it appears that my rudder burn is reappearing. I can feel some roughness in the same area where the burn was most intense before, and we have only put about 40 hours on the new rudder. It looks like the ACME 13x14 or similar would be a good choice.

I'll let you guys know how that goes, but in the mean time, thanks for your wise advice!!


It's good to hear you have made some dramatic advances!