Once again I would like some assistance in diagnosing a problem with my 92 Nautique. Here is what happened.

Had my dealer "winterize" my Nautique and having it water ready for relaunch. Have had good dealer servicing for the last 17 years. Last winter I inadvertently forgot to put fuel into the tank. (totally my fault). The tank was almost empty but during the winterization the dealer added a can of "fuel conditioner" to the tank. I put my Nautique back into the water yesterday and started the engine as I have done for many years, but it was running very rough and very rich with lots of smoke. Usually it cleared within a minute or so but this time just wouldn't run properly. I looked at the fuel gauge and it was EMPTY. Again I didn't add fuel since the winterization so I figured the engine was trying to run on engine conditioner instead of fuel. Totally my mistake so I pulled out the Nautique and filled the tank with fresh gas and tried again. This time it started up , engine sounded normal but won't hold idle and engine RPM varies heavely below 2500 RPM.

High speed is good but even there there is some hesitation or fluctuation in RPM.

At idle I can smell fresh gas. I am assuming that something got clogged up in the fuel system, filter, carburator etc.

Anyone have an idea what this could be?

Thanks to all,

 

1.  Fuel in tank at layup --  Many experts agree that you should fill the tank to 7/8 full prior to layup.  This helps mitigate condensation while allowing for some fuel expansion with the changing temperatures.

Rene,

JQ mentioned the Pro Tec becuse it could be the problem and not the carb. Check to see if it does have it. 

Thanks

How can I upload my pics?

Rene,

Here's how:

https://www.correctcraftfan.com/forum/forum_posts.asp?TID=49031&FID=7&PR=3&title=adding-images-to-your-posts" rel="nofollow - Adding Images to your Posts - CorrectCraftFan.com Forums

In case you're having trouble figuring out the picture posting, here's a picture showing where to find the list number. 

The one in the picture is 50419-1.

Thanks for the pictures.  As indicated in the metal engine tag, the engine is a PLP-PR-R12PT.  That is super-secret Correct Craft speak for:

Pleasure Craft Engine

Left Hand Rotation

P "engine" or Ford-based 351 W High Output 

Pleasure Craft Transmission

RR reverse rotation transmission

12 means 1.23:1 transmission ration

PT is ProTec engine management system

Your troubles could be caused from the carburetor, ProTec, or a combination of both.  I discussed (above) the potential carb issues.  A carb rebuild is not a big deal and may fix the symptoms.

So, you have ProTec...

ProTec was an engine management system developed by PCM.  It was a reasonably good system for its day, but now there are no longer any repair parts available if the system starts to fail.  There are many happy ProTec owners out there whose ProTec continues to perform as designed.  Sadly, there are also many owners out there whose ProTec has failed.  ProTec EMS, or Engine Management System, was designed to manage the spark distribution and timing of the engine.  The system was designed to optimize the timing advance for performance and to provide some type of protection in the event of a serious engine malfunction.  If ProTec senses a significant loss in oil pressure or a high engine temperature, the system goes into "Limp Mode" which shuts down most of the cylinders and limits RPM to just above 2,000.  The idea behind this was to allow the boat to "limp home" in the event of an engine malfunction, without totally destroying the engine in the process.  

A ProTec system that is failing can exhibit several symptoms, i.e. hard-to-start cold; hard-to-start hot; intermittent engine shut-down; limp mode when all systems are fine, etc.  My old 1994 Ski Nautique came from the factory with ProTec and throttle-body fuel injection.  I was experiencing intermittent hard-to-star problems when the engine was warm.  Then the system completely failed -- in the middle of Lake Powell, Utah.  That was painful.

If ProTec is, indeed, failing then you may want to consider retro-fitting the engine back to the "old school" distributor and coil.  Many former ProTec owners have done this and it is well documented here on CCF.  There are kits that you can purchase from SkiDim.com and NautiqueParts.com, or you can simply do it yourself and purchase the required parts as the retrofit is fairly simple.

Before you start getting all ProTec worried, I would tackle the carb rebuild.  If that solves the problem, then you may be able to get a few more seasons out of ProTec.  If the engine gremlins persist after the carb rebuild, then you may want to look at a ProTec conversion.

JQ  

For your viewing pleasure:

https://www.holley.com/products/fuel_systems/carburetors/marine_carburetors/parts/M-600

William:  Interesting question.  Here is my "take" on the situation...

QuickFuel Technologies (QFT) was started by ex-Holley engineer, Marvin Benoit, who wanted to build a better carburetor.  It is my understanding that Marvin went to Holley management about upgrading certain Holley products with the many useful upgrades now found on the QFT line.  It appears that Holley management said "NO", so Marvin left Holley in 1997 and started QFT.  The QFT designs are based on tried-and-true Holley models but with some nice improvements, enhancements and innovations.  Because QFT didn't have the same corporate structure as Holley, they were able to offer a better product at equal-to or better-than pricing.  Holley eventually realized their mistake and High Performance Industries (Holley) purchased QFT in 2012.

Now that Holley owns the QFT brand it would make for some awkward questions and answers for customers who have purchased either brand to see Holley start moving prices around.  I believe that, eventually, QFT prices will start to climb and eventually equal or exceed the Holley equivalent.  That's just my 2 cents...

JQ

They may be headquartered in Kentucky, but................do all those parts come from here in the US for either outfit?

Thank you all for your insight and knowledge. So I brought my Nautique to my dealer (has done my servicing for the last 17 years) and to be frank , the dealer is not too keen to diagnose the old 92. Basically gave me the speech, "Well you know it's an old boat and could be this, could be that ......" So I have decided to do it myself with a very good friend of mine who has a lot of knowledge who is a retired Auto Mechanic who worked on Camaro's with Holley Carbs etc.

So I want to make sure I order the right parts and if someone could just respond if what I am purchasing would work.

I would puchase the Quick Fuel M-Series 600CFM Marine Carburator -4160

I also am going to get rid of the Pro-Tec and purchase the DUI Marine Distributor Red for Ford 351 Windsor 

You'll need a new fuel line since the old one won't reach the new, different bowl fitting location.

"MSD

That could work with some additional work.

It has the wrong gear for your 351W. The 351C/460 use a bigger diameter gear.

You can't swap your present gear on to the MSD because the shaft sizes are different.

Yours now on the Pro Tec assembly is .531 inches and the MSD is .500.

You could find a gear(.500 ,cast iron, normal rotation) and a coil also to go with the distributor.

I'd probably get on the phone and call places including DUI to find out about availability, since if you look at the same distributor M35820 with different color caps, the dates all seem to be different and you might find something in stock or shipping real soon at one of these places

I think Jonny Quest and his constant, glowing recommendations for the RED cap version have created a shortage 

Or go with the Mallory kit from SkiDim, Nautiqueparts etc. Your mechanic friend shouldn't have any problems and if he does, you can ask here

If you haven't already red the thread in the link below, then read it.............it might scare you or it might answer lots of questions.

Erik made it through and has a running boat

http://www.correctcraftfan.com/forum/forum_posts.asp?TID=49747&KW=&title=removing-protec-throttlebody-installing-carb" rel="nofollow - link

Well I decided to go for it and will order the parts needed. This will of course take some time. I will most probably need support from the nice people on this forum and I'm sure when everything is done I will be very happy with my Nautique.

Keep you posted as time moves on.

I purchased FORD 351 DUI Marine Distributor RH (right hand rotation)

Item # DUI-M35820-RRBK  from SKIDM , So I just checked as discussed earlier in this thread it's a LH, so my bad, ordered the wrong part. I hope I can cancel my order at SKIDM,

They for some strange reason only list a reverse rotation DUI distributor for a 351w on their website

Or, if your mechanic is comfortable with a gear swap and getting the gear placement correct for the Ford distributor you could order a 351W cast iron gear and he could install it. 

Or reuse your present gear which should be the right shaft size and material, but it'll probably need to have the hole for the pin redrilled to fit correctly at the right height.

But............if the gear is not at the right height, you could turn your camshaft and distributor gear into junk with a lot of metal shavings in the oil of your engine

The best solution is finding one with a normal rotation gear already on it, for warranty purposes if you were to have an issue with the new distributor.

And it's quite a bit cheaper to buy one with the normal rotation gear on it 

If you decide to go the new gear route, do plenty of research about proper installation, it's easy to screw things up.

Updated June 20th, Well Keno you were right. After notifying SKIDIM that I had ordered the wrong ROTATION Distributor , I pleasantly received an E-mail from them on a Saturday (when they.re officially closed) and said they will correct my order, no problem.

So very happy about this.

Received Fuel line

DUI from SKIDIM should arrive mid July

QuickFuel Carburator B.O. until August 4th

So waiting on parts , not anyone's fault just need to wait.

 

So I now have the DUI, Fuel Line, Spark Plugs, wire set. Just waiting for the QuickFuel carburator which should arrive by early August from Summit Racing.

I will sure need some guidance on installation when doing the install.

Appreciated!

JQ

Well installed the DUI and new QuickFuel Carburator and the engine just sounds fantastic. The only issue I had was that the cooling hose from the thermostat housing was too close to the new DUI distributor as the hose had swollen at the ends over time and it was also wire enforced therefore I couldn't get the proper timing. So as a solution I installed a high temp hi pressure silicon hose.

Can't believe the difference when starting and all. Thank you for all of your input which made the install easy.

Thanks,

Hudson

Since you are Rene, just out of curiosity, who is Hudson?