Replacing Manifolds?
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Boat Maintenance
Forum Discription: Discuss maintenance of your Correct Craft
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=40230
Printed Date: November-16-2024 at 9:53am
Topic: Replacing Manifolds?
Posted By: td_in_nc
Subject: Replacing Manifolds?
Date Posted: November-26-2016 at 11:01am
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I think the previous owner of my boat (2000 Supra - yes I know not a CC) used it in brackish water from time to time (had a flush kit). One thing in the back of my mind is the exhaust manifolds. I have removed some heavy rust call off the bottom exterior of the manifolds, but they appear solid once the scale was removed and they do not leak. Also a couple of the bolt heads are almost all rusted away. The boat runs great and does not overheat. Because of the fear of the unknown or having a mid-season repair with lots of down time, I am considering as a winter project removing the manifolds and checking them out. I am sure getting the manifold bolts will be a challenge. I am guessing it is not common for manifolds to have heavy rust scale on the bottom, but I am looking for a little advice if I should take it apart or leave it alone? |
Replies:
Posted By: MACS81SN
Date Posted: November-26-2016 at 6:20pm
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Actually it is normal for the exhaust ports, portion of the manifold bolted to cylinder head, to be rusty. This area probably operates in excess of 800 degrees. At this temperature, the iron reacts with oxygen in air to form iron oxides (rust). Heating and cooling of this area causes the rust to flake off as iron and rust expand and contract at different rates Going through and testing the manifolds now and finding them okay is no guarantee something won't happen next summer or 5 years from now. I think I would just leave them alone. JMO ------------- Mark 1999 -SN - 502 Python 1981 - SN Owned 33 years - Sold 1968 - Mustang - Sold |
Posted By: john b
Date Posted: November-26-2016 at 9:55pm
I agree with macs81sn. An inspection only gaurantees they are good at inspection time. I would also suggest you just run it and enjoy it. I suspect the boat was used in salt water a good deal to be that rusty. Here is the engine in the 93 Supra I currently have under my wing for comparison..  ------------- 1970 Mustang "Theseus' paradox" If everyone else is doing it, you're too late! |
Posted By: Jonny Quest
Date Posted: November-26-2016 at 11:36pm
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John B: How is your ProTec holding up? ------------- Current 2003 Ski Nautique 206 Limited Previous 2001 Ski Nautique Open Bow 1994 Ski Nautique Open Bow Aqua skiing, ergo sum |
Posted By: john b
Date Posted: November-27-2016 at 12:37am
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Hmmmm, where would I find my Pro-tech? Is that what they call this PCM engine? ------------- 1970 Mustang "Theseus' paradox" If everyone else is doing it, you're too late! |
Posted By: 8122pbrainard
Date Posted: November-27-2016 at 8:54am
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John, The Pro-tech is the ignition system on the PCM engine. Note the 4 coil packs on the aft end of the engine and then instead of a typical distributor there's a device in it's position that senses engine rotation and position. They are notorious for failure but conversion kits back to a standard distributor and coil are available. There are some "how to" threads on the conversion. Good luck with it as parts for the Pro-tech are NLA. Just don't use the boat and you'll be fine!  ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: Jonny Quest
Date Posted: November-27-2016 at 12:23pm
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Pete is spot-on. In the early 1990's, PCM came up with the ProTec Electronic Engine Management System. The components of ProTec consisted of a combined computerized control module and coil assembly, sensor (trigger) activated by an interrupter timing system (which replaces the conventional distributor), a new wiring harness, 8 M.M. silicone ignition wires, temperature and oil switches and a knock sensor. (Your sensor "trigger" is that thing that looks like a big hockey puck where your distributor would normally go) PCM used this system on many engines between 1990 (I think) and 1994. The ProTec system was also used in the first PCM offering of throttle-body electronic fuel injection (1994). Many people consider the ProTec system to be a "ticking time-bomb" as they are prone to failure -- often without warning. Symptoms may include hard-starting, poor engine performance (as one or more of the coil packs are failing). engine running in "limp-home" mode, or engine just quits for no apparent reason. Parts for ProTech are NLA (no longer available). Something for you to look forward to... JQ ------------- Current 2003 Ski Nautique 206 Limited Previous 2001 Ski Nautique Open Bow 1994 Ski Nautique Open Bow Aqua skiing, ergo sum |
Posted By: TRBenj
Date Posted: November-27-2016 at 12:37pm
| 1991-1995 |
Posted By: john b
Date Posted: November-27-2016 at 2:43pm
Thanks for the education guys, you have my attention. I have seen Pro-Tech mentioned on the forum before but never bothered doing any research since it didn't apply to me.....until now. This must be very relevant to CCs as well as other manufacturers, I would guess there are a lot of these enginesut there. I would think it would be an easy and inexpensive fix to replace the trigger assembly with a DUI distributor. Is there something more to it than that? This boat has about 430 hours on it and has never had a problem, but I suspect it is like most electronic components and doesn't have a problem until it does. I will keep a tow line handy. I am just the guardian of the Supra TS6m. It belongs to my nephew who got it new for his 16th birthday. It has been in storage much of its life. He does his water sports these days behind a boat more appropriate to this forum. ------------- 1970 Mustang "Theseus' paradox" If everyone else is doing it, you're too late! |
Posted By: Jonny Quest
Date Posted: November-27-2016 at 3:06pm
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John: You are correct in your assessment. If/when ProTec fails, one simple solution is to replace the system with the DUI you mentioned. JPASS did a nice write-up on the ProTec to DUI swap-out. See the LINK below: http://www.correctcraftfan.com/forum/forum_posts.asp?TID=33526&PN=1&title=protec-ignition-replacement-question" rel="nofollow - LINK to ProTec Replacement ------------- Current 2003 Ski Nautique 206 Limited Previous 2001 Ski Nautique Open Bow 1994 Ski Nautique Open Bow Aqua skiing, ergo sum |
Posted By: Hollywood
Date Posted: November-27-2016 at 3:14pm
| desertskier has mentioned low voltage contributing or whole heartedly causing failure. A comparison would be welded starter solenoid due to corroded battery cables. |
Posted By: john b
Date Posted: November-27-2016 at 3:33pm
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Seems logical, low voltage-high amperage. ------------- 1970 Mustang "Theseus' paradox" If everyone else is doing it, you're too late! |