Retail the valves run 120 to 350 / ea the thruhulls are 30 to 85 /ea and there is at most 2 hr labor /ea so 350 +85  +250 would max out at about 700 - 900 including new hose clamps. But they may be quoting more work than that? did the # include, like bottom paint, hoses other work or? bottom paint sanding and repaint alone could be like 3.5K, or?

Now for your work, the notes say the valves are sezed, did they loosen the tee nut on the back of the valve before trying to turn them? (other side from the handle) and because your boat is out of the water you can take the barrels out and look at them (two screws holding the plate which holds the barrel in) Ace hardware sells silicon grease, and it is the correct lube to put them back in. (just be sure the tee is all the way out so that the plate can screw down all the way to the valve) . A side note: some grease will harden (lanacote) and the valve will not want to turn (this is fixed by taking the barrel out cleaning it off and putting silicon grease all around on the rubber and reassembling it, for as good as new (ok very used) condition but you have to be out of the water to do this.

(the tee screw on the back is the part that puts the rubber under compression and thus seals it up)

for the thruhulls take a pocket knife and scrape the bottom paint off in a couple of places (if they are pink then replace) Bronze goes a salmon color when the zinc is lost = starting to fail

I can not tell from the photos, is the wood under the valve (between the bottom of the valve and the hull) real soft? if it is rotting you would need to replace them.

In any case I still have this type of valve in my boat (no issue, but I have had to replace 2 (one for lightning strike and one for corrosion I found replacements at swap meets and boat recycle stores) so until you take them apart you can not tell. Oh the thruhull can be removed without removing the valve, but if the thruhull is in bad shape it is likely the valve is as well.

One point to look at when you take out the barrel,  the handle is connected to a bronze tube (in the rubber) that is perpendicular to the barrel. If this is bad you would be best off replacing the valve as they do not make replacement parts for these.

P.s. it will add an extra 1 - 2 Hr to each thruhull but flush thruhulls are faster. They pay off after 10 Years or so.  = an extra 0.02Kt gain in boat speed.

Lastly: your survey person has commited you to the 8500.00 ( just say insurance, they require all defects be fixed real or made up defects by the surveyor) else no insurance.

Oh Plastic tailpipes or tees are a no no (will leak or break) melron being an exception;  mine are all bronze with double hose clamps. these can set you back 50 -  100.00 ea. if you can find them

oh Do glass in #4; the engine intake can provide this service >>> less holes = better

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OH man, I looked online for seacocks and wow inflation i.e. doubled from 2006 ! a 1 1/2 " spartan is $442.00 UGH! https://www.spartanmarine.com/all-products/seacocks-for-adapter

at this rate min wage should be around 22 /hr < I guess 5% / year is a true inflation number UGH!

Nicholas

I missed the serviced option.

here is the deal if you have a pink spot or two = start planing for next haul out

all pink = you could just replace the thruhull (special tool required); but you most likely would have pinking  issues in the valve (they are connected) so not the best choice but only a full inspection can tell. A flapper wheel sanding disk on a drill can be helpfull in seeing if it is just surface dezincification or if it goes deeper.

Why no one likes the old valves! (the ones you have) turning them, is a three step process.

a.) loosen the tee

b.) turn the valve

c.) retighen the tee and ck for leeks in 20min or so. tighten more if needed

They fail when you ask someone else to close the valve (they bust off the handle because they did not loosen the tee and then you have a big problem because the valve starts leaking and will not turn). They also become inoperable if you use a grease that hardens.  But they can last, if you take care of them, but they are going on 45 year old. kind of like the boat.

for new valves;

they requires a new valve, new thruhull, fill (fiberglass in the old valve holdown bolt holes) drill new bolt holes = different hole pattern on new valve. make a backer plate (between hull and valve ) and then calk and assemble it all (WITH NEW hoses yes I know they are 12.00+/foot but it is a good choice unless yours are less than 5 years old. they have been labeling them with the dates for some time)

I am not a fan of the ball valves in any form for this service, a true seacock is a better choice in my opinion. blake, sparten, willcox or? are some options

lastly on the cost, most don't say this but 5 to 10% standard value (75K for yours) / year should be budgeted every year. just a FYI. if you bought for less then there is the extra $$ if you paid more then you did not do so good, but in any case the better you know the boat the less likely you are to have a suprise

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in case you do not have pictures http://www.trojanboats.net/wforum/viewtopic.php?t=5101

I would have linked to WOA information on the valve, but low and behold google owns that data, using java script to track my every move UGH!

I just checked your profile Nicolas , we are neighbors . Plus I have been on Blue Fin at a Rendezvous (long time ago) What yard are you in right now ? If it's Marina Shipyard in Long Beach we need to talk . Are you planning on keeping Blue Fin in the area ? 

Mark