GT-40 Hard Start When Hot
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=36856
Printed Date: January-16-2025 at 1:09am
Topic: GT-40 Hard Start When Hot
Posted By: sport1999
Subject: GT-40 Hard Start When Hot
Date Posted: July-25-2015 at 8:47pm
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Could anyone shed some light on a starting issue I am experiencing? Boat starts great when cold and runs great all day. However, after sitting (5+ minutes) when hot it will take a while to turn over (3-5 seconds) and barely wants to start at times. Has not left me stranded, but it's definitely noticeable. I've already changed the fuel pressure regulator and low pressure fuel pump. http://correctcraftfan.com/forum/forum_posts.asp?TID=36112&KW=&title=gt40-fuel-pressure" rel="nofollow - http://correctcraftfan.com/forum/forum_posts.asp?TID=36112&KW=&title=gt40-fuel-pressure |
Replies:
Posted By: lewy2001
Date Posted: July-26-2015 at 7:07am
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You need to check these to items when it is in the failing condition and report back. Do you have spark? Do the fuel pumps prime on initial key on?? ------------- If you're going through hell, keep going http://www.correctcraftfan.com/diaries/details.asp?ID=2999" rel="nofollow - 89 Ski <a href="http://www.correctcraftfan.com/diaries/details.asp?ID=5685" ta |
Posted By: NAUTIQUEjunky
Date Posted: July-27-2015 at 11:53am
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Barley turn over? Or Barely fire up and run? If the first your starter is dragging worn and is pulling to many amps and turning slow or your Battery is weak.. If the later your Ecm/fuel relays could be suspect if your Spark and fuel pumps checked out ok.. I recently had a extended hot start crank issue on my 99 gt40 and replaced my Fuel pump and Ecm relay's and it fixed my issue.. They are standard old school ford relays.. Duralast/Auto Zone # 19272 if you wanna do the local parts route.. ------------- 1977 MasterCraft Stars&Stripes 1994 Ski Nautique 2000 Super Air Nautique 1986 Ski Nautique 2001 1999 Sport Nautique gt40 current |
Posted By: sport1999
Date Posted: July-27-2015 at 5:10pm
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It would be the later, 'barely fire up and run'. We do not lounge much, so the condition has been hard to test. Battery is new and I don't get the impression of a weak starter. I also hear the fuel pump(s) prime, too. The best I can describe is extended cranking and barley fire up and run. Once running, no issues. Sometimes I have to turn the key multiple times and/or takes a few seconds until it starts, only when hot. The condition usually occurs when turning the boat off at the dock or when changing skiers/riders. I may need to let it sit for 15-20 minutes to find out if there really is a problem. I have a fuel pressure gauge, extra spark plug and a spare relay for testing. My plan is to test back at the dock and start with spark/fuel pressure when hot. |
Posted By: NAUTIQUEjunky
Date Posted: July-27-2015 at 9:23pm
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Dylan, Sounds like your in the same situation I was, I'm IMOP the Gt40 is one of the best motors PCM has ever produced and many on here will say the same.. Although it does have its quirks/common issues like any other engine.. Make sure both low pressure and high pressure pump prime when u turn the key to Start postion.. Sometimes it's best to actually put your hand on the low pressure pump to feel it buzz because it can be muffled by the HPFP.. Do you have a Spark checker? If so check spark when your engine fails to start.. If the spark is weak your Coil could be going South or the Ignition module.. but the Module's on these motors harldy ever fail.. Its almost always a fuel pump or relay issue on a hot/soak starting issue...like I said switch the ECM and Fuel pump relays out.. I would also recommend reading the Poor Man's gt40 diagnosis on here.. It's a sticky thread ------------- 1977 MasterCraft Stars&Stripes 1994 Ski Nautique 2000 Super Air Nautique 1986 Ski Nautique 2001 1999 Sport Nautique gt40 current |
Posted By: Canuck-Surfer
Date Posted: August-24-2021 at 10:02pm
Did you ever figure this out? I am having the exact same issue, only while hot though. Cold engine cranks instantly, hot engine turns over for 4-6 seconds before starting. For others who mentioned fuel and ECM relays, are the relays impacted by heat?
------------- 1996 Sport Nautique GT40 EFI |
sport1999 wrote:Posted By: Gary S
Date Posted: August-24-2021 at 10:49pm
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Anything is possible-switch them around one runs the pumps the other the ecm. I always carry spares of them in the boat. Ever change the distributor? ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=1711&sort=&pagenum=1&yrstart=1966&yrend=1970" rel="nofollow - 69 Mustang HM SS 95 Nautique Super Sport |