Print Page | Close Window

Pro Boss GT 40

Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Engine Repair
Forum Discription: Engine problems and solutions
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=36092
Printed Date: October-07-2024 at 10:52pm


Topic: Pro Boss GT 40
Posted By: Left Lane
Subject: Pro Boss GT 40
Date Posted: May-19-2015 at 1:22pm
I have a 1995 Hydradyne with a EFI 351 pro boss GT 40. My issue is, when I park it after running it for a little bit the boat wont start back up unless I start it within 20 min of shutting it off if I wait longer it wont start again until the engine is completely cooled down.. It will turn over fine but it wont fire. Any Ideas?

-------------
Left Lane 95 Hydradyne



Replies:
Posted By: Left Lane
Date Posted: May-19-2015 at 1:23pm
I just put a new coil on it so I don't think that is the issue


-------------
Left Lane 95 Hydradyne


Posted By: Hollywood
Date Posted: May-19-2015 at 1:30pm
How do we know it's the right coil?

You have to do some diagnosing first, are you starving for fuel or not getting spark.

The early GT40s were prone to vapor locking.

-------------


Posted By: Left Lane
Date Posted: May-19-2015 at 1:52pm
I just went off of the coil number that was on the boat in the first place. I haven't checked for spark. When we tow it in and the air goes down through the hull from the intake vents up on the bow it will start also. Would the LP and or HP fuel pumps have anything to do with this?

-------------
Left Lane 95 Hydradyne


Posted By: Gary S
Date Posted: May-19-2015 at 2:08pm
I don't think there are many choices with Gt40 coils like regular oil filled ones. Do you have 2 pumps on it? I seem to remember a PCM guy tell me they added an extra pump. Mine has 2,the high pressure one is the one that's connected right to the fuel rail and has the return on it. In my case there's another connected on the same bracket just before the high pressure one. Have you by chance opened the engine cover and let it cool off some and seen if that helps?

-------------
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


Posted By: Left Lane
Date Posted: May-19-2015 at 2:50pm
Yeah Gary that sounds like the same set up ive got. Yeah that works sometimes. It seems like its starting to take longer for it to fire compared to last year. On mine there is a high pressure fuel filter on it too. Ive just found it. Also it seems that one of my fuel line fittings is loose. its not leaking just loose


-------------
Left Lane 95 Hydradyne


Posted By: gun-driver
Date Posted: May-20-2015 at 12:04pm
I've been fighting this on my '95 the last two years. So far I've only replaced the TFI but not sure that solved it. I now carry an arsenal of test equipment waiting for the problem to arise.
I carry a fuel pressure gauge that screws to the shrader valve, spark tester, and Lewys jumper wire setup to jump the fuel pumps.
My current thoughts are the low pressure fuel pump, but have not had the chance to test the theory as the condition is so intermittent.




Posted By: malibud
Date Posted: May-21-2015 at 10:20am
Had the same problem on a 95 replaced filter, both fuel pumps (i had extra parts laying around ) finally figured it out it was a fuel pressure regulator. I had a varied fuel pressure (habor freight ) gauge. The pick up screen in the tank is a B*tch


Posted By: Left Lane
Date Posted: May-21-2015 at 10:30am
So your boat was doing the same thing, wouldn't start after it ran for a while and when you replaced the regulator it fixed it?

-------------
Left Lane 95 Hydradyne


Posted By: Left Lane
Date Posted: May-21-2015 at 10:36am
this problem happens every single time I take the boat out on the LAKE

-------------
Left Lane 95 Hydradyne


Posted By: phatsat67
Date Posted: May-21-2015 at 10:55am
Originally posted by gun-driver gun-driver wrote:

I've been fighting this on my '95 the last two years. So far I've only replaced the TFI but not sure that solved it. I now carry an arsenal of test equipment waiting for the problem to arise.
I carry a fuel pressure gauge that screws to the shrader valve, spark tester, and Lewys jumper wire setup to jump the fuel pumps.
My current thoughts are the low pressure fuel pump, but have not had the chance to test the theory as the condition is so intermittent.




Just upgrade boats Paul . Wait, you just 4 footers behind it again to recreate the issue!

-------------


Posted By: malibud
Date Posted: May-21-2015 at 11:19am
Take off the low pressure fp clean the screen, get a new inline fuel filter, Get a fuel pressure tester plug it into the port on the fuel rail you should have steady flow around 40 psi (i think you can look it up in manual)


Posted By: Left Lane
Date Posted: May-21-2015 at 11:22am
ok and that is at idle?

-------------
Left Lane 95 Hydradyne


Posted By: malibud
Date Posted: May-21-2015 at 11:38am
I think so but look at the manual it is posted here ...95' did not have the fuel cell . also if you can clean the anti siphon screen in or near your tank


Posted By: Left Lane
Date Posted: May-21-2015 at 11:43am
Ok cool Thank you. Did your 95 only do it after you ran it for a while and then after it cooled down it would start? I just saw in the manual I down loaded that they also have a coolant temp sensor as well

-------------
Left Lane 95 Hydradyne


Posted By: Bri892001
Date Posted: May-21-2015 at 2:48pm
Take a look at this thread:
http://www.correctcraftfan.com/forum/forum_posts.asp?TID=25584&title=poor-mans-gt40-diagnosis" rel="nofollow - http://www.correctcraftfan.com/forum/forum_posts.asp?TID=25584&title=poor-mans-gt40-diagnosis

Keep in mind you've got your ECM and Fuel Pump relays in there too. Often problematic, and heat related failure is a primary symptom.


Posted By: Left Lane
Date Posted: May-21-2015 at 2:58pm
Thank you I appreciate all of the feedback. I was just told it's most likely my ignition module

-------------
Left Lane 95 Hydradyne


Posted By: malibud
Date Posted: May-21-2015 at 3:00pm
thats true I would start by replacing those two and keep spares in the boat napa has them . and yes I would have the same problems start run great for 15 mins then run like poo .spudder then would not start


Posted By: lewy2001
Date Posted: May-21-2015 at 8:50pm
You need to diagnose when it is in the no start situation.
Check for spark and fuel pressure.

-------------
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: gun-driver
Date Posted: May-21-2015 at 10:16pm
Originally posted by lewy2001 lewy2001 wrote:

You need to diagnose when it is in the no start situation.
Check for spark and fuel pressure.


Listen to Lewy on this. With this intermittent problem the only time you can diagnose it is when it is in the no start condition.

Zach didn't mine do it at Tim's after pulling the barefooters I'm thinking that's what your referring to.

Also the problem of diagnoseing the problem is trying to do it before cools off and starts as usual. Mine starts with one turn of the starter all the time until this problem hits then it's no start when it cools it's back to one turn of the starter.




Posted By: Left Lane
Date Posted: May-21-2015 at 10:18pm
Put the ignition module on today and so far so good. I will keep you all posted

-------------
Left Lane 95 Hydradyne


Posted By: Bri892001
Date Posted: May-22-2015 at 9:36am
cool, let us know how it turns out.



Print Page | Close Window