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Indyblackhawk
05-16-2006, 02:12 AM
The stringers on our LE BH are completly rotted out. We are wanting to fill them with a ki that is a fiber compound. My question is; how far back do the stringgers go? DO they just go to the fire wall, or more forward? Also, any suggestions on how to fix this would be greatly appreciated.

We have been pretty dissapointed with the quality of our Donzi with rotting out and all. We take great care of the boat so we have no idea what went wrong. How well made is the Z line of Donzi's? We are wanting to get a more off shore boat for our house in florida and are now doubting Donzi after this. Looking into either going all out and getting a Cigarette or possibly looking into a Baja.

Thanks for any advice

Pismo
05-16-2006, 09:18 AM
Check the transom thoroughly too. This is the only time an old style boat with an easily removable floor so you can get to the stringers is better. Good luck, so sad to hear.

MOP
05-16-2006, 06:59 PM
The moisture may stop near the rear seat as mine did, I still overlapped and doubled the stringers to meet the forward most bulkhead roughly 5 feet. The back end of my stringer were wet but still white wood and very solid, where they met the transom was the bad spot. There was not glass to isolate the ends of the stringers from the transoms wood section, more then likely the transom is wet also. It appeared as if what water did get in was from the stringer drain holes and the the hull drain plug. At the advice of the glass guy the new transom wood was cut straight across from the bottom of each stringer eliminating the V dead wood, the area below was built up of solid glass just shy on 1 inch. Drying stringers in my opinion is very hard, it is best to cut them out and replace them. Tommy "Rust & Rot" can supply "Rot Proof" marine plywood with a life time garentee. I used a similar CCA treated 7 ply marine plywood for my stringers, I have been testing a piece half buried in the dirt by my gutter pipe to keep it good and wet, it is over a year now with -0- rot or glue delamination. Well worth the cost.

http://www.greenwoodproducts.com/xlpanels.htm

Phil

Greg Maier
05-16-2006, 09:22 PM
Indy,

Have the same problem with my Blackhawk. Currently undergoing a complete resto. Stbd stringer was completely rotted out. Transom was also rotten. I almost pulled a K-Plane through the transom and sank. Also have some rot in the forward stringers where the fuel tank was screwed in. Donzi did a poor job sealing the boat up after all the hardware was installed. What else can you say but shoddy workmanship.

gcarter
05-16-2006, 10:19 PM
My Minx stringers were not rotten, but very wet. I cut out the stringer-hull joint material with a grinder so that the stringer bottoms were open. Once they dried out, I filled the gap with thickened epoxy. I did this for about six feet, port and starboard. I formed a generous radius on both sides of the stringers with more epoxy and glassed over the radii.
A trick that's used in drying out hulls for osmotic blister repair is to tent the boat, install several de-humidifiers and fans to circularte the air under the tent.
You could accomplish the same thing in your bilge by taping a plastic drop cloth over your deck, including the engine vents and cockpit. Put a de-humidifier in the bilge, run the drain out the transom plug hole, and a fan to circulate the air. If you were to continue this for several weeks, the boat would definately dry out. Many times dry wood, you'll find, can recover remarkably.
I also epoxied the wood in all the holes through the stringers. Additionally I noticed the stringer drains were poorly placed and no where near where they needed to be. I used a hole saw to cut drain holes through the stringers tangent with the hull and about six inches in front of the transom. Then I epoxied PVC pipe into these drain holes and completely sealed the stringer/pipe joint. Now you can run a water hose wide open into the hull outside the stringers and no water collects in that area.

LKSD
05-17-2006, 07:44 AM
The stringers on our LE BH are completly rotted out. We are wanting to fill them with a ki that is a fiber compound. My question is; how far back do the stringgers go? DO they just go to the fire wall, or more forward? Also, any suggestions on how to fix this would be greatly appreciated.
We have been pretty dissapointed with the quality of our Donzi with rotting out and all. We take great care of the boat so we have no idea what went wrong. How well made is the Z line of Donzi's? We are wanting to get a more off shore boat for our house in florida and are now doubting Donzi after this. Looking into either going all out and getting a Cigarette or possibly looking into a Baja.
Thanks for any advice

I would stay with Donzi. If you do leave a formula or cig are the only ones that will probably come close to comparing. The Baja while not a bad boat will truly be dissapointing if you are going to go that way after a donzi... Kind of like going from a Ferrari to a camaro... If you need the boat repaired I can do the work for you depending on the time frame you are in. Call me if you need me.. Jamie / lakeside 570-639-2628 :) :)

Indyblackhawk
05-17-2006, 03:16 PM
Thanks for all the responses......

the wood in the stinggers is not just rotted, its basically gone. I can put my finger in the drain holes on either side and just pull lots of wood flakes out. Also, we custom made some engine mounts and when we were tightening them down, the stingers were starting to pull through even just at hand tight.

Jamie, how much would a job like this cost to have done?

LKSD
05-17-2006, 04:29 PM
Thanks for all the responses......
the wood in the stinggers is not just rotted, its basically gone. I can put my finger in the drain holes on either side and just pull lots of wood flakes out. Also, we custom made some engine mounts and when we were tightening them down, the stingers were starting to pull through even just at hand tight.
Jamie, how much would a job like this cost to have done?

Feel free to call me It's easier to discuss it with you by phone.. You can email me your # & I will call you or you may call me.. @ 570-639-2628 Jamie :)

Btw: Not to scare you but it could easily get into the thousands.. :umbrella:

wannabe
05-18-2006, 04:08 PM
Was this boat kept in the water for long periods of time (all summer at a dock)?

cigarette30
05-18-2006, 09:55 PM
Was this boat kept in the water for long periods of time (all summer at a dock)?

I would be interested in that also.... less than ten years old and rotted stringers, sure not a good thought huh? I keep mine on a lift, and zero, and I mean zero water in the bilge, even wipe up the excess after washing.

I had the factory/dealer install the two batteries far to the rear to have more access, as well as seal the drains from the upper stringers better (thanks to a few suggestions on the Donzi Registry)

BTW, it's the ONLY boat I have ever had that I can run for hours and have dry bilges, seems you also pick up a little water somewhere, not this one. (YET lol)

Indyblackhawk
05-19-2006, 02:22 AM
We are the second owners of the boat. We've had it about 5 years now and have always kept it coverd, on a covered lift. How the last guy treated it is now a mystery. Now we are a little worried that the transom may also be rotted. Hopfully going to fianlly pull it from winter storage next weekend and assess everything.

MOP
05-19-2006, 06:04 AM
No matter how well you have treated you boat there is a big contributing factor which I discovered last year at 1K, there was a very heavy down pour and Bonnie and I were trapped on the island with nothing better to do but watch the rain. I looked out at the Beast and noticed the bilge pump going on way more times then I thought it should, though I had water proofed the cockpit cover I thought it was the culprit. When the rain stopped I pulled the cover off to find the interior bone dry, then it dawned on me the engine hatch is a huge water shed direct into the bilge. I did a test with the garden hose toward the front end it looked like about 75% drained into the bilge. Donzi like all other manufacturers cut drains through the stringers and do not seal the opening, in the case of our boats all of the hatch water drains on the outside of the stringers and has to drain through into the center bilge. When I re-did the stringers in mine I tried to do a good seal job on the holes, so much water getting into the bilge still bothered me. I decided to make up overboard drains for the engine hatch, I will seal the forward drains in the hatch channel and install 5/8" copper tubes at the aft end which will dump overboard. I would advise all to check the condition of the wood where it drains through and do something similar to drain it overboard we know the results if we do nothing.

Phil

MR MAGOO
05-19-2006, 06:27 AM
I've got an old 1983 18 2+3 that's left in the water from May to October every year. Also have a 22 Sea Ray Pachanga been in the water every season since 1986. No rot at all. Boats should be made to live in the water.

I guess some boats are not made very well right out of the factory. Pretty sad considering how much they charge for them.

Pismo
05-19-2006, 08:54 AM
Wood is just the worst, modern boats should be made with no wood at all. Just because the wood is completely encapsulated does not mean it won't rot out either. Modern epoxy encapsulated classic wooden boats rot out faster than anything out there. The solution is no wood (like Formula has done)

Craig S
05-19-2006, 09:13 AM
Modern epoxy encapsulated classic wooden boats rot out fast than anything out there.

imho, traditionally-built epoxy encapsulated wood boats rot. Modern boats designed to be built with epoxy do not. For instance, I don't think Grand Crafts have an issue here. Are Donzi stringers made of built up plywood?

Morgan's Cloud
05-19-2006, 10:22 AM
Was there a time when Donzi went through a period where they were using inferior quality plywood ?
I know that I have read elsewhere that Wellcraft was notorious for this and there are loads of 'newish' boats built by them that are no good now .
Phil raises an interesting point about the cover and the rain and how I believe it relates to a boat staying in the water by Mr Magoo ...
I've seen more boats rot out here on land because they fill up with water that can't drain out than I have seen boats rotted because of sea water intrusion..... Although like Phil mentioned a while back , salt water tends to preserve the wood .

gcarter
05-19-2006, 10:43 AM
I know many boats use plywood for stringers, I know because I've had some.
IMHO, plywood isn't the best material because only half of the wood grain is going in the direction it needs too. The vertical grain is only adding thickness, but no strength.
FWIW, the mid '80's Donzis seem to have clear pine stringers. That's the way mine and Truesers was, and that's what I replaced the transverse frame with.

Pismo
05-19-2006, 11:59 AM
Many of these West System encapsulated new wooden classics are having problems. The West system does nothing but trap the water inside. The new method is all mahogany construction with CPES, no plywood, etc but it will take 10yrs until we know if that works.

MOP
05-19-2006, 12:03 PM
Plywood is down and dirty but if kept dry will last as long as the boat, wet wood will be a problem sooner or later. Several boat manufacturers have used foam to form the stringers with a heavier layup, in critical areas like engine and transmission mounts the inserted hard fillers. I have done some glass over foam work it is amazingly strong, the weight comes out about the same as glass/plywood but is not as cost effective due to the extra glass/resin needed to equal the strength. It is easy to see why many builders stick with the plywood.

Phil

Just Say N20
05-19-2006, 12:14 PM
Where I work we use a sandwich of 1/4" plywood, foam, and then another 1/4" plywood. This is simply a material to provide shape for the glass. The strength of the stringers comes totally, by design, from the glass build up, thus making any "wet wood" potential down the road irrelevant.

gcarter
05-19-2006, 12:30 PM
The strength of the stringers comes totally, by design, from the glass build up, thus making any "wet wood" potential down the road irrelevant.
This is a true statement.
Unfortunately most Donzis (and many other boats I've seen) just use the 'glass as weather proofing.

Indyblackhawk
05-19-2006, 02:02 PM
The bildge pump does not pump the bildge completely dry. My bad, I should have been sponging the bildge dry after each use. The boat has been caught out in the rain and I would only quickly rag off the engine and stringer box. With the boat storred on a covered lift, I wasn't pulling the plug to drain - I would just run the bildge pump and I know there was always a little water left in the bildge. What about oil? I had a valve cover leak that left an oil mess - will oil contribute to rot? Is a salt water boat preserved by the salt water?

Morgan's Cloud
05-19-2006, 02:10 PM
Is a salt water boat preserved by the salt water?


AS far as I can tell my St T has been a salt water boat its entire (40+year) life.
When I replaced the transom last year , it was the original trans, it was wet about half way up from the bottom, but no discernable rot .... hmmmm

Greg Maier
05-19-2006, 07:08 PM
My transom was cored with 1 inch by 2 inch strips of plywood with flexible caulk in between them. They were arranged vertically like a parquet floor. I'm not sure why they did that, maybe it was the curvature of the transom.

MOP
05-19-2006, 08:52 PM
Greg my transom was a bunch of over lapped blocks about 5"X5" the logic may have to keep water from migrating through it. I think 95% or better of transom rot starts at the drain hole and works up and outward, that why I eliminated the lower V section and went straight across. Most builders do not isolate the the various wood parts from each other water wicks from one to the another. All the wood in mine is isolated plus I am anal about a damp boat, I have a strip of towelstuffed in the drain which gets out the last few drops. I use a solar fan on 4" PVC running up to the cockpit while its covered on the trailer to circulate air.

need for speed
05-19-2006, 09:31 PM
I always take 5 more mins in my wash time and suck the bilge dry with my shop vac and dry her out .. every time!...it keeps it dry and makes everything last longer .. :)

Indyblackhawk
05-20-2006, 10:12 AM
Not sure yet if we are going to fix this ourselves or just hire it out........ Checked out our local baja dealer yesturday and looked at a 35 and 40 Outlaw. Pretty sweet boats and we are getting pretty excited about getting a true off shore boat. Maybe we should just trade in the Black Hawk, the 4 blackhawk outdrives, 5 sets of props and the 95% set of mercruiser/ blackhawk specific tools we own.............. Naw, hopefully we can get it running and keep it up here

cigarette30
05-21-2006, 09:44 AM
I will seal the forward drains in the hatch channel and install 5/8" copper tubes at the aft end which will dump overboard. I would advise all to check the condition of the wood where it drains through and do something similar to drain it overboard we know the results if we do nothing.
Phil

Phil, have you done this yet.... pis would be great. Whats your thoughts at least dumping in the center bilge, I am not much on any more holes through the hull.

MOP
05-21-2006, 04:26 PM
Phil, have you done this yet.... pis would be great. Whats your thoughts at least dumping in the center bilge, I am not much on any more holes through the hull.

For trailer guys like me the center bilge would be fine, I keep my plug out when not in use. But I would rather shoot it over the side when the boat is in the water, I rarely leave it in except when I am up at the St. Lawrence. Last year it rained for nearly about hour so hard I could barely see the boat about 100 feet away, I could see the big Rule working overtime when it was over the battery was noticeably low that's is why it will go over board. For guys on hoists that do not pull the plug it would pay to dump it over board, pulling the plug on the hoist can a real pain unless you have 6 foot arms.

Phil

cigarette30
05-21-2006, 06:43 PM
For guys on hoists that do not pull the plug it would pay to dump it over board, pulling the plug on the hoist can a real pain unless you have 6 foot arms.
Phil

Or, good balance ....... LOL

MOP
05-21-2006, 08:16 PM
:rlol: :rlol: I have been dumped in the drink a few times when I had hard dinks!

Indyblackhawk
02-05-2007, 10:09 PM
We still need to fix our stringer problem, hopfully this winter. We decided to buy a true off shore boat and after looking at Cigarette and Donzi, we wanted somthing with more cabin space. We went ahead and got a Formula 382 Fas3Tech w/ Merc. 600's

Ed Donnelly
02-05-2007, 11:49 PM
Indy; Have fun with your new boat,and, you still stayed in the Aronow family...Ed

Walt. H.
02-06-2007, 01:27 AM
Dang!,
Thats truely a big dollar combination, lotsa luck and enjoy!!

94-more days until launch time,
Walt

Pismo
02-06-2007, 06:19 AM
We still need to fix our stringer problem, hopfully this winter. We decided to buy a true off shore boat and after looking at Cigarette and Donzi, we wanted somthing with more cabin space. We went ahead and got a Formula 382 Fas3Tech w/ Merc. 600's

The real good news is that your new 382 has no wood in it. No rot in your future with this boat.

glashole
02-06-2007, 06:56 AM
what are you doing with the old boat? :)

osur866
02-06-2007, 07:08 AM
Does anyone know if the classics still use wood in the construction of the stringers or did they change to something else, and if so what year of any changes?

Donzigo
02-06-2007, 08:23 AM
The last time I went through the plant, I saw many boats still using the plywood or other wood plus fiberglas stringer construction. The wood gives a from for the fiberglass to be adhered to and therefore a fiberglass beam is made. The wood, while important, is not stronger than fiberglass. Having said, that, I want my stringers to be dry and whole; so, I would repair any stringer that was rotten on a boat I wanted to keep for years to come.
During the late 80s on some of the Donzis, there have certainly been stringer issues. But, these issues don't signify bad workmanship, any more than any other boat manufacturer at the time. Some of the Donzis built during that time seem to have more problems than earlier or later models. I had a 1986 & 1986 Donzi and still own a1989 Z-33. The Z-33 has zero problems, the 1986 C-22 had some and the 1987 Z-25 had a complete rebuild of all stringers for the cost of $14,400. I figured it was my last Donzi to own; so, I wanted it right.........yeah, right, then I was looking at the paper one Saturday morning and saw a RED Z-33 for sale, a few miles from my house. So, David and I took a look...........a month later i owned it. Go figure. Then, a guy flew down from Vermont to look at the 1987 Z-25. I was going to keep it, had no interest in selling, and he said he just wanted to see a nice one to know what to look for. (he had been flying all over the US looking - collects Porsches & Ferraris). Having coffee after a ride, he writes this check and now I have a situation...........I look at the check then the boat.........OK, so I sold it to him. Great guy and we still are freinds today.
The moral of the story: When it comes to Donzis - never pre-judge what you might do................like dude, don't offer a drink to a drunk. OK, so I saw this RED - 38ZR with the yellow Ferrari symbol on the side somewhere a while back on Offshore Only or maybe it was for sale at the time, can't remember, don't want to remember...........I think it's in lake Tahoe...........hell, I'm scared to death that I might see this beast in Florida one day, with a "for sale" sign on it........ OMG - I could get drunk again................(for more information on this condition - consult Joe Griffin - aka - CUDA).