500hps 380 hrs what to do
02-05-2007 | 06:57 AM
#11
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From: pa
Re: 500hps 380 hrs what to do
let met this straight.... you are going to do all that work if the leakdown is GOOD ? why bother w/ the leakdown at all ? the only thing standing between you and a complete freshening at this point is a handfull of oil pan bolts and a set of rings. the logic of doing all the diagnostics just so you can rattle it almost all the way to pieces anyway escapes me.
as far as the leak down numbers go , you can believe what you want... sure... single digit numbers are wonderful but a good solid motor when cold will give you some numbers in the 12 and 15 % range which wouldn't bother me in the least... and if you are telling me that you are going to warm this thing up in the boat, then strip the plugs out and get the leak down done in any reasonable sense without really having a miserable day... well youre a better man than i.
it sounds to me like your mind is made up to go for more power... just make the decsion, take them apart and do it. thats going to be anall or nothing deal...
why would you think of going thru all the work you are discussing just to leave old bearings and rings in it ?
not trying to give you a hard time... just don't understand your approach.
as far as the leak down numbers go , you can believe what you want... sure... single digit numbers are wonderful but a good solid motor when cold will give you some numbers in the 12 and 15 % range which wouldn't bother me in the least... and if you are telling me that you are going to warm this thing up in the boat, then strip the plugs out and get the leak down done in any reasonable sense without really having a miserable day... well youre a better man than i.
it sounds to me like your mind is made up to go for more power... just make the decsion, take them apart and do it. thats going to be anall or nothing deal...
why would you think of going thru all the work you are discussing just to leave old bearings and rings in it ?
not trying to give you a hard time... just don't understand your approach.
i was asking for advise so thanks, the aproach is that i do not have to pull the motors out of the boat to do what i mentioned. but i agree 100% that i should just pull them and do it all, or wait another year then do it rite when im more ready?. and really my main post was weather 380 hrs is somthing to worry about on these motors.
Last edited by rssteiny; 02-05-2007 at 06:59 AM.
02-05-2007 | 08:25 AM
#12
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From: Naples, Maine
Re: 500hps 380 hrs what to do
Rick,
I hear ya man! My boat was running fine but I had 300+ hrs on the power. I knew I should refresh but they were still running fine. When we did the leak down test, it told the real story, one motor had 3 cyls with 50-70% leakage. The other motor had two bad holes, 50% and 90% leak.
Too many hot suppers
!
See ya at the Pirates Run AARRR!
Kurt
I hear ya man! My boat was running fine but I had 300+ hrs on the power. I knew I should refresh but they were still running fine. When we did the leak down test, it told the real story, one motor had 3 cyls with 50-70% leakage. The other motor had two bad holes, 50% and 90% leak.
Too many hot suppers
! See ya at the Pirates Run AARRR!
Kurt
02-05-2007 | 01:16 PM
#13
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From: pa
Re: 500hps 380 hrs what to do
Rick,
I hear ya man! My boat was running fine but I had 300+ hrs on the power. I knew I should refresh but they were still running fine. When we did the leak down test, it told the real story, one motor had 3 cyls with 50-70% leakage. The other motor had two bad holes, 50% and 90% leak.
Too many hot suppers !
See ya at the Pirates Run AARRR!
Kurt
I hear ya man! My boat was running fine but I had 300+ hrs on the power. I knew I should refresh but they were still running fine. When we did the leak down test, it told the real story, one motor had 3 cyls with 50-70% leakage. The other motor had two bad holes, 50% and 90% leak.
Too many hot suppers
! See ya at the Pirates Run AARRR!
Kurt
02-05-2007 | 05:25 PM
#14
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From: Castro Valley, California
Re: 500hps 380 hrs what to do
heavy ol doesnt flow very well through tight tollerances.... that motor was built around 10-30 or at most 25-40W not 50W oil... tollerances are tight and wear actually could be increased as the pressure spring opens before full oil FLOW through the motor occurs.. and the pump will bypass most of the oil back into the pan...
Larry
62 Bel-Air 409
260 Eagle XP HP500EFI
2002 Corvette M6 Coupe
02-05-2007 | 06:56 PM
#15
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From: beaumont tx
Re: 500hps 380 hrs what to do
I would think the bottom end is fine, but the heads will most likely need a mild surface, then a valve grind, have the machine shop check the valve seats real good and the springs, crankshaft bearing clearance on a 500 is .002 to .0025" to me a tight tolerance motor is less than .0015"
02-06-2007 | 08:37 AM
#16
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From: Naples, Maine
Re: 500hps 380 hrs what to do
Even though they might run fine, you never know until you look around
http://www.offshoreonly.com/forums/s...d.php?t=150745
http://www.offshoreonly.com/forums/s...d.php?t=150745
02-06-2007 | 04:24 PM
#17
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From: Denmark
Re: 500hps 380 hrs what to do
05-09-2007 | 09:06 PM
#20
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From: Ray Twp. Michigan
I agree seems people have a urge to mess with performance boat engines before they need it.And generally if they try to save a buck doing it they end up worse off then they started.
