Messages

Hi Gary,

One thing you need to know about the remote location option of the panel in the XC series charger is that while it can be removed from the main unit, there is no mounting means provided for it except for some rather permanent adhesive backed tape already in place around the periphery of the panel. If you ever want to be able to remove it from a mounting location, you will have to make a backing plate with a cutout to permanently mount the remote panel onto, and then mount the backing plate + remote panel assembly with screws in the corners. Not a very well thought out design detail in my opinion. The lip around the panel is relatively small, and drilling mounting holes in it could result in warranty issues in the future.

Also, as I noted previously, the XC series chargers for now(?) should only be used with flooded batteries because of over-voltage issues in the float mode with AGM batteries.

Regards,

John
1988 C34 wing keel
Hull 728
Otra Vez

Here are few random comments on various topics emerging in this discussion, in no particular order.

Xantrex Echo Charge Function If you are using the built-in function contained in the larger Freedom Series inverter/chargers, be advised that you do not want to use the Echo Charge function with any low internal discharge batteries: i.e. - any form of AGM or Gel battery technologies. The way the Echo output(s) receive their power internally in the Freedom unit causes high voltage spikes to propagate through the Echo output and can result in float voltages appearing across connected low loss batteries up to 16 volts. This will result in rapid degradation of the positive plates in the battery and seriously reduce the useful life of the batteries. I haven't specifically looked at the stand-alone Echo charge module in detail, but I have seen the same problems appear with them when used with a few older chargers and some alternators that had "dirty" outputs.

Link 10 Replacement The old Link 10 has been directly replaced by the new Link LITE, and with one or 2 features unavailable in the basic Link 10. Of particular interest, the Link LITE provides for the display of a second battery voltage on the internal display much like the Link 1000 provided. The accuracy of the Link LITE is comparable to the original Link 10, and I think retails for a little less than the Link 10.
The Link PRO has all the features of the LITE but at higher internal accuracy for voltage and current measurements, and therefore all computed charging parameters are also more accurate. The PRO also offers a few features not available on the LITE, and the retail price is about 15 to 20% higher than the PRO depending where you buy it.

Truecharge2 I noticed that Xantrex has now dropped the ridiculous idea of having this charger available in 7 different output current levels. It is now produced in either 20 or 40 amps like it's predecessor. If you are using flooded cells, you will definitely be using the equalize function, and without the optional remote panel you will only be able to activate the equalize function from the control panel built into the charger, which means you will have to provide for physical access to that part of the charger unit. Unlike the remote panel option for the Truecharge+ series ( which was almost worthless ), the remote panel for the Truecharge2 will let you fully utilize/program any features available from the charger.

Microwave Ovens and Psuedo-Sine Wave Inverters  With a large fully charged battery bank, a non-smart "psuedo-sine wave" ( i.e. bastardized square wave ) inverter will sort of work a microwave, but always at reduced power output.  I have used one that way, and it was better than heating up the cabin in the summer with the regular stove or oven. As the battery voltage reduces, however, the microwave power starts to drop in a hurry and quickly becomes almost useless.
If you want to use the microwave a lot and effectively, you will have to go with a smart true sine wave inverter that will allow the microwave to maintain it's normal peak power output over a larger battery output voltage level range. As an added bonus, the microwave and some fans and power tools won't "growl" at you as the battery voltage level drops.....

Xantrex XC Series Chargers In my on-going evaluation of this product, I have discovered some disturbing characteristics when used with low internal loss batteries ( AGM for sure, and maybe Gel ) that I have discussed with Xantrex personnel and am still awaiting their response to my disclosures and questions. I'll update my previous product review on Xantrex chargers once I have received a response from Xantrex. For now, I will caution everyone to only use the XC Series chargers with flooded cell batteries.

Regards,

John
C34 Otra Vez
1988 wing keel
Hull 728

Copied to the Battery Charger Evaluation thread (http://c34.org/bbs/index.php?topic=4352.0)  November 10, 2008 - Stu

A wise move! As I noted in my previous posting, push-on spade terminals are out of favor with me, especially at anything over about 10 amps since they are just a problem waiting to happen. I always will use screw terminals ( the "K10" version I mentioned ) on circuit breakers and almost anything else aboard a boat for improved reliability.

Welcome to the site!

John
C34 Otra Vez
1988 wing keel
Hull 728

An interesting thread, Stu. Your final observation is very pragmatic and absolutely correct, particularly if you have flooded cell batteries and their lower acceptance rates due to higher internal impedance. If you are using AGM or even gel batteries, your "charge it back up at home" discharge level will be higher by about 10% or more, again because of the lower internal impedance of the newer battery technologies.

One point worth noting is that "hot" is very much a relative thing when talking about an alternator. It is not at all uncommon for alternators to regularly run with case temperatures in the 200 degrees F range, which is the temperature that Powerline and several other manufacturers use as their "hot operation" reference temperature. These temperatures will burn your hand/fingers pretty easily and make you think something is terribly wrong based upon your "damned hot to me" impression. As bad as that sounds ( or feels ), it is on par with other engine components found under the hood of a car, and well designed alternators will run for long periods of time at those temperatures without noticeable reduction in service life.

Most alternators that die from over-heating will do so from a slipping belt. At higher rotational speeds and high loads, the slipping belt will heat the pulley and rotor shaft to many hundreds of degrees. These elevated temperatures will cause the front bearings to fail first, which then causes the whole front case and rotor of the alternator to get even hotter. I have seen an alternator rotor that got so hot in this situation that the solder melted out of the slip ring terminations of the field winding. Needless to say, this sequence quickly becomes a catastrophic failure of the alternator.

While increasing air flow to the alternator is never a bad thing, the real killer is improper belt tension. If you are running a single 3/8 inch belt and a high output alternator, you need to watch your belt tension like a hawk. The nifty belt tensioner tool in a previous article will become your alternator's best friend, and make tensioning your belt easy enough that you will be without excuse. Got to get me one of those!

[Ed  Stu]  See: http://c34.org/bbs/index.php/topic,3667.0.html

Regards,

John
1988 C34 hull 728 "Otra Vez"

While the installation info that comes with the Truecharger+ series chargers does recommend fuses in the positive leads, this family of chargers already has internal fuses on each output: 30 amps on each output of the 20+, and 60 amps on each output of the 40+. I can vouch for the ability of the internal fuses to give up the ghost appropriately, but replacing them is a little messy and you have to know the "secret handshake" about how to successfully get the unit apart ( after you remove it from the mounting location... ). ( Please don't ask how I know so much about this subject  ..... ) The only time I have ever seen one of the fuses get blown is an accidental short of an output feed to ground or a reverse connection. The external fuse will be a lot easier to replace than the internal one.

John

First of all, don't bother having your Dyteck charger repaired: it is not a very desirable charger, and will produce charging voltages that are excessively high on your nice Trojan 6 volt batteries. The Guest 2615 is a 2 stage charger that is not a terrible charger, but has already been replaced in the Guest product line by an improved version. The primary problem is that it doesn't have sufficient capacity for your 225 a-hr per bank battery capacity, it does not have a well regulated float voltage, and cannot be configured for optimum charge performance with flooded batteries.

My best current recommendation for you is to install a Zantrex Truecharge 40+ charger. They can still be found at a quite reasonable price on the Internet, and will do no harm to your Trojans when properly configured.

The Trojan 6 volt batteries can give very good service if they are well cared for and properly maintained, which includes periodic equalization charge, something the Guest charger cannot provide, but the Zantrex Truecharge will perform.

John

The video, while explaining the basics of the "back and fill" maneuver, fails to demonstrate what I think is the most important feature. By using non-idle power ( i.e. - aggressive applications of power ) in forward and reverse, the distance moved forward and in reverse can be almost nothing - you can make the boat just pivot around the keel ( hence, the "pivot turn" ) and at a fairly impressive turn rate even from a dead stop.

The times I generally am inclined to use this maneuver combine all the things you don't want: crosswind or current from a bad direction, and not much room in which to turn. This translates into not much time to spend getting turned around, and the faster you can get turned around the less time the wind or current has to try to send you hurling into something big or hard or expensive.

I encourage everybody to go out and practice this very useful maneuver enough times and in a variety of conditions so that you become very comfortable with it. The C34 does it very nicely. You will finally come to love prop walk .

John

I'm going with Ken on this one. The big blast of power followed by NO power to the prop will indeed give you the ability ( sort of, cross wind permitting ) to turn to starboard. In our previous 1991 C34 with a 3 bladed prop from 15 years ago, that technique got us out of the slip regularly. Our current 1988 with 3 blade also responds to this technique, but now it is less important in that the boat house behind us in now about 125 ft behind us rather than the 70 ft from 15 years ago.

The good thing about the 3 bladed prop and it's pronounced prop walk is that it enables you to do a mean "back and fill" that it very handy and will let you generally turn 180 degrees CW in about 1.2 boat lengths or less without breaking a sweat. With 20 kts of wind off the port bow last Saturday, turning to starboard during backing wasn't going to happen..... Just turned to port to get out of the slip and then did a 'back and fill" CW turn get turned around for the trip out of the marina. Works every time.

John

Thanks for the editorial endorsement, Jon. Your check is in the mail......

You are correct about the lack of any "flickering" if you only have one battery connected to the XC. Under those conditions it would have "disqualified" the other 2 banks and would skip them in the sequential bank charge cycle, leaving only 1 battery in the "loop". You would never see any intensity change for all practical purposes under those conditions.

Thanks for the info.

John

The COMPLETE Charger Evaluation is here:  http://c34.org/bbs/index.php/topic,4352.0.html

[Installment #3: Xantrex charger review and associated comments.]

Installment #3: Xantrex charger review and associated comments.

The actual comparison tabulation is attached as a pdf file. I tried only to list the areas that could be meaningful in normal usage. There are other shared features with small technical differences, but I judged them not worthy of much discussion. All of them have various protection features for either the charger or the batteries, so there wasn't too much point in dissecting the small print.

If you scan across the product offerings, you will note that the Truecharge2 (when it ever is actually available...) is a poor substitute for the Truecharge+. If the offered price at WM holds, the Truecharge2-40 charger + BTS combo costs more than the equivalent price of it's namesake. Not only that, it offers a significant feature loss with the elimination of the 2 stage charge protocol option ( more on that later ). The only advantage that the "2" offers over the "+" is being about 5 inches shorter in length and about a half inch shorter in height. If that is not an issue, the "+" wins hands down.

After careful reading of the product information for the XC series, I can see a few things to like compared to the "+". The on board control/display panel insert is removable and can become a fully functional control / display panel, which I think is a nice improvement over the pretty dumb and way-too-big remote display-only panel offered with the "+". The XC also retains the option of either 3 or 2 stage charge protocols, with the addition of an improved float mode which, although not well described, appears to have the ability to function in a pseudo-inactive float mode after spending a reasonable amount of time in the active float mode. For the record, a full charge can only be achieved by either an active float mode charge ( constant regulated voltage at less than bulk ) for many hours, or at the absorption voltage for an extended period of time, or a charge at the absorption voltage until the actual battery charge current gets below a relatively low threshold. If the pseudo-inactive float mode works as implied, the 2 stage charge protocol becomes less important except for a few limited number of specialty cases.

The big advertising hype for the XC focuses on the ability to mix battery chemistries between the 3 banks. While this sounds good, in most practical applications is has little importance. A mix of flooded cells and AGM batteries can be done using only the AGM charge parameters. Not many people use true gel cells any more, and if they do, it's usually all gel cells because of the problems associates with single source charging from the main engine alternator. While it's true that the multiplexed or sequential charging of the 3 banks means that each battery will be presented with an optimal charge step series based upon the charge state of the particular battery bank, the down side of this scheme is that as you sit on your boat at night with the cabin lights on, there will be periodic and noticeable light intensity changes as your house bank goes from being on charge to off charge. In this scheme, only one battery bank at a time is actually under charge. [ Jon, can you comment on how noticeable this is in the real world?? ] Since on my boat my primary battery charger will be the Prosine 2.0 inverter/charger, I am pretty committed to single source charging at the dock or underway, and the equivalent of multi-source charging for my single house bank and dedicated starting battery ( all AGM ) is not a big issue.

If you spend long periods of time away from your boat, and you don't have "shore power phobia" , then the XC series offers an optimized solution to keeping all your batteries well cared for in your absence with the sequential/multiplexed charging and the pseudo-inactive float mode.

If you are only away from your boat for a less than a month at a time, either the "+" or the XC versions can keep your batteries and your boat safe in our absence. You can accomplish 90% of what the XC can do in this situation with the "+" by placing it in the 2 stage mode after you have fully charged your batteries before your departure. Any of the Xantrex chargers with the 2 stage mode available will automatically come out of the inactive state and initialize a new 2 stage recharge if any battery falls below 12.5 volts for more than 15 minutes. In addition, it will automatically initialize a new charge cycle every 21 days from the last recharge cycle, or upon a new application of AC power to the charger. Those of you who worry about your Mother Of All Bilge Pumps running for hours at a time in your absence can rest easy as long as you have shore power available.......

For those you still using flooded cells, the automatic full recharge cycle every 21 days is especially important to you if your are away from you boat for significant lengths of time. Flooded cells have one not well recognized problem associated with sitting with no charge or on a float charge for long periods of time: acid stratification. What this means is that when a flooded cell sits still for long periods of time, the acid separates into different levels within the cell based upon the specific gravity of the acid. The portion of the acid that has the highest specific gravity settles to the bottom of the cell, with decreasingly lighter acid in layers above the denser acid. If you recall basic lead acid battery chemistry, low specific gravity is associated with lower charge levels, and higher specific gravity ( within certain limits ) with higher states of charge. Once this happens, the average state of charge of the battery decreases because most of the plates are in contact with a non-optimal acid mix. This can produce a significant loss of usable capacity. The good news is that it can be easily corrected by bringing the cell voltage well above the gassing voltage ( i.e. – to the absorption voltage ) and producing lots of bubbles: the flow of the bubbles up through the cell plates causes the acid to remix and restore a homogeneous specific gravity throughout the cell. This action also replaces charge lost through internal self-discharge of the battery ( only when left off charge: it doesn't occur on float charge ), which with flooded cells can be as high as 20 to 30% of capacity per month. To make matters, the lead sulfate which forms because of self-discharge turns in the crystalline form more quickly than that which results from heavier discharge, and the crystalline form does not readily convert back into lead dioxide during normal recharging. Lead sulfate will turn into the crystalline form in about 45 to 60 days. Once your battery has lead sulfate in crystalline form, your battery has what will usually become a permanent capacity loss. This is what having your battery "all sulfated up" means. Most flooded cells need to be completely recharged every 30 to 45 days to avoid permanent sulfation.

OK: time for the BOTTOM LINE.

Truecharge 40+: Old but very good. Best feature set per amp of charge capacity. Can deliver first rate battery care in probably 90% of all applications. Has an exceptional field reliability history. Probably will get scarce once the Truecharge2 is available in large numbers. For now, Practical Sailor John gives it a "Best Buy" rating among the Xantrex selections.

Truecharge2-40: Newer than new ( not available currently ), "cute" with it's modern look and smaller size, and capable of handling most normal applications. Lack of 2 stage charge protocol makes it less able to deal with unique situations. It will likely be reliable after the bugs are worked out of it ( and there will be some.... ). I doubt that the small current steps between models will be maintained once the product is out in the real world: too many production and inventory variants, and no justification technically for less than about 2:1 steps in charging current between models.  I would buy a "+" now rather than wait on this one to become available.

XC3012/XC5012: I wanted to not like this series based upon price and what I initially considered to be some gimmicky features. However, after careful study, I have to revise my opinion. Yes, it costs more per amp than a near equivalent "+" unit, but it does have some features that offer the possibility of longer battery life in a more automatic, transparent manner than other Xantrex or other brand offerings. Also, the fixed/remote control/display panel included as part of the basic package is a plus in some applications; if you already have a battery monitor system that can tell you all you want to know about your batteries ( and why wouldn't you??? ), the remote display is not a big deal.  If the pseudo-inactive float mode works as indicated, that is a big factor in achieving true "plug-it-in-and-walk-away" battery care that has been unavailable in the consumer market up to now. Even though I need yet another battery charger like another hole in my head, I'm probably going to buy one just to put it through it's paces and see if it can realize the potential I think it may have. I won't say that I think you should go buy one, because I generally only do that based upon positive personal experience. You can buy one and experiment with me, or wait for my update in 6 months or so.

Well, I still have some battery and charging things on my list to pontificate about, but that will have to wait for Installment #4.

Hope this is useful.

John
 

As a follow up to Installment #2, here is the schematic ( attachment ) for the AC-DC change-over relay and power supply wiring for the AC power supply addition to your Cold Machine. After looking over my original notes on the subject, I determined that the original 250w power supply that I used with my older Cold Machine compressor ( pre-2000 vintage ) was rated as 12v/17a. I also noted that I had adjusted the output voltage up to about 13.2 volts for maximum efficiency for the compressor. The 17a current rating is a continuous rating, and this power supply easily handled the substantial starting load surge of the older compressor.

Based upon this information, there are actually 2 better options for power supply selection for the pre-2000 compressors. If you don't mind configuring a pair of units for parallel operation, you can use a pair of 100w units from www.mpja.com, part number PS1-100W-SF12 at $32.80 each. If you would rather have a single unit, use a 240W unit from www.jameco.com, part number 137649 at $106.85. This unit has a 2 year warranty and a cooling fan that only runs on demand, which in this application will be almost never.

Craig, if you add the AC power adaption to your fridge, it can be cold all the time if you have shore power available at the dock . I think I'll stay away from remote diesel heater starting............

John

Here we are again with installment #2, and the main topic here will be the AC-to-DC power supply usage with the Adler-Barbour Cold Machine.

First, a little background and history of the Adler-Barbour compressor. Prior to early 2000, all the compressors were fixed speed, brush commuted motors that had a very nasty current spike when the compressor started, but also were very electrically noisy while they were running. The installation manual for these units made a strong point of using big wire from the battery and the fact that you had to have a battery on the feed circuit to help "absorb" the current feedback of the motor back into the voltage source. Upon starting, the peak starting current was in the neighborhood of 17 amps for a couple of hundred milli-seconds. However, my discussions with the engineering folks back then ( pre-WAECO ) confirmed that with a reasonably "stiff" power supply ( i.e. - AC-to-DC power supply ) there was no reason that the compressor wouldn't be happy without a battery in the feed circuit. Of course, I had already tried it by then and knew that to be the case, but it made me feel better having them agree with me...... I used a 250w 12 volt nominal switching power supply with the output voltage set at about 13 volts, which meant that I had about 19 amps available. I used this from the end of 2002 with no problems on my Stamas 44, and the next owner is still using it. The power supply had a cooling fan that ran all the time, and the fan quit after about 3 years. However, since the run current of the compressor was only about 5 amps, the cooling fan wasn't really necessary anyway, and it wasn't an issue. However, the supplier of that power supply no longer carries or makes that power supply, so to duplicate what I did will require some adaptations ( at least at a reasonable price..... ).

For the post-2/2000 Cold Machines, the compressor was changed to a variable speed brushless motor in a slightly larger and more efficient compressor, the Danfoss BD50. The variable speed motor starts "softly", and the maximum start current is less than 10 amps. This means that a 150w power supply provides ample reserve to start the compressor, and really coasts along at the 4 to 5 amp run current. The motor also runs more electrically "quiet", which is a very good thing if you have other radio receivers on the boat. This is what I have now on Otra Vez.

For change-over from AC to DC power, I use a standard SPDT 30 amp automotive relay with the relay coil power by the AC power supply. The common terminal of the relay goes to the compressor, the NC contact of the relay goes to the DC feed circuit breaker, and the NO contact of the relay goes to the output of the AC power supply. If the AC power supply is powered up, the compressor runs from shore power; if not, it runs from the house battery bank. When I'm away from the boat with the charger turned off, I leave the fridge DC power turned off at the distribution panel: if shore power goes away, I don't want the batteries run down just to keep the beer and bottled water cold for a few days.......

The power supplies I have used on both the Stamas and the current C34 both came from www.mpja.com. The 150w power supply I use for the newer compressor is part number  16020 PS and costs $40.75. If you have an older compressor, you can use a pair of the same units in parallel after carefully setting the outputs to have equal voltages before tying the outputs together. If you want to pay more and have a better warranty, you can use part number 709-S150-12 from www.mouser.com at $57.96 each. I should note that the cheap units from MPJA have worked without a hick-up for 5 years and counting being turned on 24/7.

When I have the schematic diagram of the power change-over relay scanned into a suitable format, I'll post it here as well.

For installment #3, I'll summarize my comparison of the TrueCharge+, TrueCharge2, and XC series of chargers. We'll of course ignore the fact that the TrueCharge2 is currently still marketing blue sky.......

Until later.

John

Hi everyone! Sorry to be so late for the party! Given the late hour, I'll probably have to do this in several sessions, but I'll try to answer all the questions eventually.

First, let me say that I am a mixed-bagger: I keep ( for the last 20-ish years) AC power on the boat 24/7 to keep the beer cold, and to keep the inside temperature of the boat reasonable with my wonderful 16,000 btu of reverse cycle air-conditioning. Down here in north central Texas, the boats never leave the water, and our temperatures can change about 100 degrees F from February to August. We don't have to worry about salt induced corrosion  up here, but I did the same thing while I had the Stamas 44 on the Texas gulf coast for 9 years by exercising reasonable preventative measures to prevent salt from causing potentially dangerous electrical hazards at the dock and on the boat. Having said that, the explanation for my veiled comment about not leaving the battery charger on 24/7 ( but not for the reason you might think ) is that I have no problem with AC power on all the time, but I have some technically sound reasons to not keep any kinds of deep cycle batteries on a charge 24/7.

All battery do not like having residual charge current flowing through their plates for extended periods of time. However, for our discussion here, I'll limit my comments in particular to deep cycle lead acid batteries. As Stu accurately quoted some of our direct correspondence, the problem created by continuous charge/residual current flow through lead acid batteries in positive grid corrosion. This is something that happens anyway during the charge process, but when the charge to float mode time ratio becomes mostly float mode, the grid corrosion continues to happen with no useful effect on the battery, so that the positive grid corrosion is highly accelerated. The grid corrosion produces increased internal impedance ( i.e. - reduced cranking capability ) and reduced deep cycle capacity from the loss of effectiveness of the positive plates. The relative reduction of capacity percentages I cited due to continuous charging versus cycle charging come from 2 primary sources: manufacturer's data, and my own empirical data from messing about with deep cycle batteries extensively since 2000. The primary manufacturer I have worked with is Concorde Battery, who manufactures not only the Lifeline AGM batteries, but also a complete line of aircraft and aerospace batteries in civil and military applications. The same family that owns Concorde Battery also owns Trojan Batteries, so the experience base there is pretty broad. Trojan was the premier manufacturer of submarine batteries during the diesel/electric submarine era. They are also still the leading manufacturer of golf cart batteries, among other batteries.

The stated 35 to 40% maximum reduction in useful life of a deep cycle lead acid battery due to continuous float charging was based upon Concorde's own testing and their experiences in field applications of their batteries in solar power applications ( the ultimate cycle charge environment ). My own customer experiences and the results of my own studies with the Lifeline batteries supports the stated range of useful life reduction with some reduced effect if the float voltage is temperature compensated and well regulated at the lower end of the allowable float voltage range. In the last several years, Concorde/Lifeline has reduced their recommended float voltage range from a nominal 13.4 volts to 13.2 volts, and this will further reduce the rate of positive grid deterioration in the float mode. In one of my own examples, the new AGM 4D batteries I installed on my Stamas 44 lived about 3.5 years in constant float mode at a temperature compensated 13.4 volt nominal. At the end of that time, the measured cranking power ( CCA ) and deep cycle capacity was reduced by about 20%. The next 1.5 years was spent using cycle charging, and the measured CCA and a-hr numbers were only about an additional 5% lower. I have to note that these examples are from premium grade AGM deep cycle batteries, and the results from a relatively inexpensive flooded battery would probably be significantly worse.

So, if 24/7 float charge is bad, what to do about 12 volt refrigeration ( i.e. - your Cold Machine )? The simple answer is to provide a suitable AC-to-DC power supply to run the fridge when you are at the dock, and then run it on the batteries when away from AC power. I have been doing this since 2002. There are a number of inexpensive and suitably reliable small switching power supplies out there that will do the task admirably.

One last quick comment: I like the TrueCharge + series because it has been an extremely reliable product with good features and performance at a fair price. I have never seen one fail at all in normal service in 8 years, and more importantly, never fail in a mode that produces an uncontrolled high output voltage across the batteries. This is in stark contrast to may of the other charges that were in use on boats over the same period of time. I think the TrueCharge II has excellent potential, but I want to see some in operation over time before I offer any additional opinion. I think the XC series is over-priced and touts primary features that offer little benefit in the real world.

This will have to be it for installment #1. I'll keep working down the list of questions and comments as quickly as I can.

John

I have had good luck with some of the Island Girl products [ www.islandgirlproducts.com ] for a variety of cleaning and restoration projects on fiberglass and vinyl. For tough stuff like 3M 5200 and Cetol, I would use the Neutral cleaner since it is a more potent cleaner that the Pink. The Island Girl cleaners will basically remove anything from gel coat that has not chemically combined with the gel coat. It will do no harm to your gel coat! You can call Jim at Island Girl and see what he recommends procedurally.

Good luck.

John
1988 hull no. 728
Otra Vez

Sorry: forgot to include the search engine address. http://afdcmap2.nrel.gov/locator/FindPane.asp

John