Engine Rebuild Interval Thread
Printed From: CorrectCraftFan.com
Category: General Correct Craft Discussion
Forum Name: General Discussion
Forum Discription: Anything Correct Craft
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=48792
Printed Date: March-05-2025 at 10:36pm
Topic: Engine Rebuild Interval Thread
Posted By: Crmaverick
Subject: Engine Rebuild Interval Thread
Date Posted: June-03-2020 at 12:02pm
| Here’s a thread to post how many hours everyone putting on their engines before rebuilding. How many hours can you typically go before needing atleast a hone job and piston rings? |
Replies:
Posted By: Jonny Quest
Date Posted: June-03-2020 at 12:29pm
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There are a lot of factors to consider, not just hours. I’ve seen many well-maintained marine engines that have over 2,500 hours in a ski boat application. Long hours at high RPM can shorten shorten Life. High performance mods and higher compression ratios can also impact engine longevity. You can run a top-end rebuild if the pistons, mains and rod bearings are OK. You could squeeze out some additional life that way. JQ ------------- Current 2003 Ski Nautique 206 Limited Previous 2001 Ski Nautique Open Bow 1994 Ski Nautique Open Bow Aqua skiing, ergo sum |
Posted By: GottaSki
Date Posted: June-03-2020 at 12:36pm
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Any symptoms, or you just want to stay ahead of it? Its summer, not the time to take it apart! That engine has been apart before, correct? Its sister boat has over 2000 hours, never apart. an indmar mastercraft i know got 3000 hours before it fragged. Leakdown test would give you a barometer of its innards' health. ------------- "There is nothing, absolutely nothing, half so much worthwhile as messing around with boats...simply messing." River Rat to Mole |
Posted By: Orlando76
Date Posted: June-03-2020 at 1:04pm
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I have a boat I bought with 383 hours on it, super clean, but 1 cylinder was low on compression which made engine run rough. Replaced that motor. I have another boat with over 3000 hours on original 1975 Waukesha. It’s getting tired, holeshot is getting longer, top end is still reasonable but that 3000+ hour motor runs so damn smooth and clean, until it fails we can’t justify touching it. Maintenance plays a part, luck plays a bigger part. ------------- Please support The Cystic Fibrosis Foundation 1976 Ski Nautique 351 Escort 1993 Ski Nautique purple and black 351 HO PCM |
Posted By: DVskier
Date Posted: June-03-2020 at 1:13pm
| I have a friend with a 1998 Malibu with 4,20o hours. Other than replacing a low pressure fuel pump and regular oil changes, raw water impeller the engine has never had a wrench on it. Of course he runs only non ethanol fuel (that many forum members decry as “unnecessary”). The key is he runs the boat regularly and pays attention to engine temperature, oil level, etc. He has owned the boat since new. |
Posted By: Crmaverick
Date Posted: June-03-2020 at 1:46pm
For sure, I wouldn’t pull it apart for a few more seasons at the earliest and during a winter. I was curious and wanted to stay ahead of it, approaching 900 hours. The engine hasn’t been apart before according to the second owner. It does use about a half quart oil every 10 hours or so. Do you know if the sister boat uses any? I hear that hi po motors can tend to do that with loser tolerances. Also valves seals are going so that contributes some. I got a bore scope and took some cylinder pictures attached, looks like typical cylinder wear. https://drive.google.com/file/d/1ev9DsNqHkNCnbr8BBm85oDaWZiSjtfFe/view?usp=drivesdk" rel="nofollow - https://drive.google.com/file/d/1ev9DsNqHkNCnbr8BBm85oDaWZiSjtfFe/view?usp=drivesdk https://drive.google.com/file/d/1YFLxg_eWJm1xvcj8Dbw2qUP0f0t5qmcu/view?usp=drivesdk" rel="nofollow - https://drive.google.com/file/d/1YFLxg_eWJm1xvcj8Dbw2qUP0f0t5qmcu/view?usp=drivesdk |
GottaSki wrote:Posted By: MrMcD
Date Posted: June-03-2020 at 2:49pm
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My 1978 Nautique ran 1,100 hours before it started fouling one spark plug regularly. Turned out it had one burnt valve not sealing any more. We installed just new heads, switched to some old 289 HI Perf heads that had been ported and polished with larger valves installed. A friend who was heavily involved in racing offered them to me. They pumped up the compression having smaller chambers and that old 351W had a lot more power than ever. Did not use any oil between changes. We sold that boat at 1,600 hours and it was still running very strong. After 1984 or so the new boat engines were built with Moly top piston rings. They are much softer on the cylinder walls causing much lest wear, probably doubling the cylinder wall life. Keep it tuned up and enjoy it. ------------- |
Posted By: KENO
Date Posted: June-03-2020 at 6:12pm
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Hey Mav I heard a rumor that you got your Delco EST distributor issues ironed out  |
Posted By: Crmaverick
Date Posted: June-03-2020 at 6:33pm
I did that advance curve was no good, tried two modules. The new Davis distributor has a perfect curve |