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View Full Version : What is low hours???



DUCATIF1
02-20-2003, 05:34 PM
What do you guys consider low hours in regards to engines and drives??? 250 middle of the road?? Thanks

MOP
02-20-2003, 05:49 PM
This one should get some response, I think your in the ball park with the way Donzi's are run. Weekend warriors that never go over 3200 get two to three times as much

Dr. Dan
02-20-2003, 05:52 PM
:cool: Duc........The hours of any boat or vehicle are directly related to age and maintenance history! A 10 to 20 year old ride with only 200 hours would be considered very low....a boat with 2 seasons of operation with 200 hours would be considered alot.....but again this is all relative!

We found our 1993 22 Classic....we purchased it as the 3rd Owner...after surveys, compression tests.......and the general condition of the boat being categorized as "very clean for it's age".....all opinions suggested our boat had less than 100 hours of operation(there was no hour meter)....and likely closer to 50! We lucked out, however some one who maintains there boat and uses it all of the time may have alot of hours on it (Poodle, Tomahawk...or many others) and I would not hesitate to purchase their boats.regardless of the hours on the meter! We average around 60 hours per season/year. I hope this helps wink .........Doc

Greg Maier
02-20-2003, 06:10 PM
Hey Doc,
Do you have EFI? When the computer is hooked up to an EFI Engine, the actual hours will display. My hour meter and the hours in my ECU are off by 20 hours, the hour meter being higher. I was told that if you leave the ignition on it will run up the hour meter.

FASTEDDIE
02-20-2003, 06:30 PM
Some comments on hours. Simple compression tests will tell the story. I bought a boat that had 73 hours on the meter. If the boat has the Mercruiser computer chip, 1994 or after, MPI or EFI, Mercury dealers have a plug in tool that reads the chips actual engine running hours. Mine read 57 hours. I asked how the chip reading could be different from the hour meter and it was explained to me that even if the key is turned on to listen to the radio, the hour meter will record hours. So, not all hour meters are correct. The newest hour meters are now designed not to record engine hours until the engine revs exceed 900 RPM'S. So ,idle at 650 to 700 doesn't count nor listening with the ignition key turned on to the accessory position.
One of the better engine builders told me once , that a fair guage on the 350 Merc, 260 HP is to rebuild it anytime after 800 hours of use. As you can see, its your best judgement call based on digesting all this information.

HyperDonzi
02-20-2003, 08:29 PM
Is there any general hours/yr? like with cars, 12-15k/yr is pretty average?

Hours dont also show how hard its driven, could be at wot or at idle.

Hardonzi
02-20-2003, 09:00 PM
Let`s not forget here in Fla. we boat year round,so hours are gonna be higher. I would much rather have a boat that was run and maintained then one that sits and seals warp,hoses dry out and internal parts rust. I`ll put my 22ZX against anyone with as many or a whole lot less hrs. and see who picks what. It`s on the classifieds and a new pic is at www.spectrepowerboats.com (http://www.spectrepowerboats.com) pre-owned sect.

Shanghied Again
02-20-2003, 09:13 PM
All depends on how well the boat has been maintained and run, My 26ZX has 160 hours the first year I change my oil every 25 Hours like clock work, My 22 Zx had over 300 hours when I got rid of her on a Supercharged motor, Never burned a drop of oil. You can tell a pig boat sometimes by looking at it, If the boat is clean inside and out with a clean bilge runs clean no noises are odors, Oil is clean no leaks, Then she was taken care of. The person who tries to clean up the boat when they sell always miss something.

abelchinewalker
02-20-2003, 09:51 PM
Like Frank said as long as the fluids are changed regularly you should be fine. Take a close look (and sniff) in the bilge, if somethings not right you will see (or smell) it.
Usage is not always a bad thing sometimes you can do more damage by lack of use. My grandmother is replacing her 1984 Ford LTD II this month, the car only has 36,000 miles on it, but since she doesn't drive it all the belts, hoses, and tires are deteriorating. Just put a new carb on our 1973 18 Classic last year due to lack of usage (couldn't be reubilt again), and I'm sorry to say that I have not had her out since Mt Dora last March, can't wait to see what I find this year. But I will say that the fluids are changed regularly and I've never experienced any engine or drive failure. Up til last year the boat was being used regularly in both fresh and salt water.

Donnie

Rodger
02-20-2003, 10:07 PM
An engine can have a lot of hours on it and still be in great shape. I just finished disassembling my turbo 454 that I built 15 years ago. It has 1200 hours on it. I can still see the cross hatch honing on the cylinder walls and the most taper I'm able to measure in a cylinder is only .001". Bearing journals are still round and to the .010/.010 undercut that I did when I built it. Valve seats and guides look very good. I run an entire season on the same oil change. I have a 15 qt. pan and use 2 oil filters with no bypass but I do change the filters half way through the season. I use synthetic oil but no brand in particular; just whats on sale. I never go over 1800 RPM until the oil temp gets to at least 160 degrees. I kind of wish I didn't take the thing apart. It doesn't appear to need any work.

DUCATIF1
02-20-2003, 10:34 PM
Rodger I would love to know your combination? 1200HRS and you still see cross hatch pattern on walls? What kind of stones did your machinist use?? Your rings are properly seated?? Moly? The pattern is there to seat the rings so after that many hours with no oil consumption and proper pressure how do you still have pattern?? 10/10 is the undersize of the cut on the crank at your rod and main bearings journals, what are your clearances??? no bearing wear?? Considering all clearances are set at "tight" clearances during build up that is amazing amount of wear .001?? Most break in of bearings and related surfaces should show a lot more wear than that just to seat properly?? What the heck are you using in that thing??? Synthetic oil does reduce wear but parts have to seat and that is why synthetic oil is not used durng break in or atleast 500-1000 miles of use. What parts are used? pistons? bearings? rings?? I guess my question should have been how does hours relate to miles??? I am still stuck on your claims? Most engines run on the principal of .004 clearance for every inch of bore for upper moly rings. What were your initial settings?? Upper ridge is caused by heat, oil consumption, and combustion conditions not wear. I am amazed and hats off to your or you for your combination. I am skeptical. Brian

Digger
02-21-2003, 06:12 AM
go to www.rinda.com (http://www.rinda.com) click on marine application to get your very own software that will get your ecm to spill it's guts.

MOP
02-21-2003, 07:33 AM
Poodle I bet like me you have seen some pretty high hours on the clock and got a nice surprise at the interanals. I have a 53 Hat that I have sold three times one engine at 4500 hours still made it through survey by Cliffy Sousa a well known tough guy in my area. I can not vouch for the first owner habits but know that the others had deep pockets and did all the right stuff. Also note Rodger built his own as I did, he and I are confident that we did a better job then most. Up here you have guys that love the boats and the wrenches that finess them. Anyone up here will use the best parts available, truely it only cost a few bucks more to use the best. I like many even though I have gone the extra mile do frequent oil samples on my stuff. Also when selling any boat I insist the buyers do the same.

Rodger
02-21-2003, 08:50 AM
Ducatif1,
I used Sealed Power forged pistons, Speed Pro .035 rings (moly) @.004"/inch of bore on the top ring and a little tighter on the 2nd ring. The TRW bearing clearances were .0025". I did break the engine in on normal oil and the first season I do a few oil changes including one at about 20 minutes after the initial start-up. This is the best wearing engine I have ever built, although I 've had some good results on others also, following a similar protocol. Keep in mind that I'm only running 7.8-1 compression which keeps the heat down in the upper cylinder area except when I'm generating boost. This probably helps some.

DUCATIF1
02-21-2003, 09:22 AM
I am spending way too much time on this site. I guess the point I was trying to make is the reason to put finish crosshatch pattern on walls is to seat rings. 1200 hrs is a lot of hrs to still see pattern. Now when you tell me you still see pattern I am expecting to see a pattern throughout the walls. With modern rings they do seat faster and do not tear up the walls as much and require a different stone. A properly set up pattern and matched rings will be gone at those hours and the rings will be fully seated? The rings will have worn the pattern off. Honestly I have no idea how miles translates into hrs?? If that is about 10k miles the pattern should be worn. What kind of rings you guys using in those deisels? I never worked on a deisel and am always amazed at the pressures they run at. I think i heard the same thing about the Vettes and I doubt Chevy is pre running them. But then again they have the wear clearances and metals used a little better down then us backyard mechanics (speaking for myself). After all of that I am assuming the 250hrs is not excessive and we all agree the maintenance of those hours is more important than the hours itself. I am now off to calculate my cars mileage into rough hours??? Thanks

Rodger
02-21-2003, 11:06 AM
It's difficult to convert hours to miles. I used to equate 2500 rpm in a boat to about 60 or 70 MPH in a car. If your average boating is at about 2500 RPM that would be about 60,000 miles or so for 1000 hrs. of use. 60k miles is not alot on a car these days. Of course it's not the same kind of use. A boat engine is alway loaded; maybe similar to a car pulling a trailer or going up a hill. So, who knows? It probably isn't worth trying to compare hrs. to miles. Just be glad if the thing is running well.

Trueser
02-21-2003, 11:30 AM
How is a cleaner running boat motor figure into this equation ? No road dust or dirt.

My boat has 440 hours still runs strong.
350 Magnums

BUIZILLA
02-21-2003, 11:57 AM
1 hour of passenger vessel operation = 35 miles in real time. your mileage may vary..

this is the truck and industrial industry standard..

i just took apart an engine yesterday, that has 22,000 original hours..

J

MOP
02-21-2003, 02:16 PM
They do run in a cleaner enviroment but even when babied have a very harsh life compared to cars. In a car you mash the gas get up to speed and let off. In our boats we are operating similar to fairly hard acceleration all the time. At cruise I would say we are at about half throttle, try keeping your car at half throttle. I bet you will be doing 85-90 pretty quick. I know that I am at about 1/4 throttle when I am doing 80 in my car. I don't get to do that much just on my trips up state. I am not sure what others have found, but with the gas stuff burnt valves, detonation damage and overheats topped my list. Very few wear outs, lean conditions, timing and poor fuel, cooling system problems did 95% of the motors in that I worked on.

Bryan Tuvell 33ZX
02-21-2003, 09:55 PM
Great thread, the maintenance is the key, we put 157 hours on our new boat this past season, but changed the oil/filter every 30 hours (that is pretty damn often too) and did the drive lube just as often, yes over kill, but I don't care. Plus documented scheduled maintenance from a Merc mechanic is an added bonus.
As for the old boat, hour meter was 300, computer was 267 I believe, checked at trade in.
I would buy a boat from me, but not too many others when it comes to used boats. Maintenance is costly and time consuming, only the true lovers of the sport, with the extra budgeted dimes do it routinely, let alone save every receipt.
My Donzi bag is full of receipts, dated, hours on each one. I buy for 2 changes at the store each time, that way I am never dreading a run for supplies.
To bad Merc drive lube is so expensive, more would change it more often, need it or not, based on others opinions.
Lastly, IMHO, if a boat is flawless overall, the owner probably did the maintenance and can prove it.
As always, buyer beware.
Bryan