502MPI - Intermittent Crank, No Start
#11
I'm taking it out tonight to see what happens. It's hot and humid today, so should be a relative test. I'm planning to take my spark tester, Fluke, and the service manual. I'm almost hoping that it does exhibit the condition so I can get to the bottom of this.
I appreciate all of the advice - I'll report back with the results.
I appreciate all of the advice - I'll report back with the results.
Even though ambient air had cooled off, the engine compartment stays hot for a looooong time. And after the vapor lock has pushed the gas back to the tank (assuming you don't have a check valve) you still have to crank like you ran out of gas. Try running slow with hatch open slightly for a little while before shutting it off or running blower for a while after you shut it off and see if problem disappears. My guess is it will.
#12
Registered
Join Date: Jul 2004
Location: Michigan
Posts: 139
Likes: 0
Received 0 Likes
on
0 Posts
Like was mentioned before, If the battery has enough to crank engine normal speed there is most definitely enough voltage to run ecu/fuel pump and injectors. If it were a hot electrical component problem then jumping would not help. When my hp 500's do it I crank and it fires for a split second then quits and I know I just ran the little bit of fuel in the fuel rail out and have to crank and crank and crank to prime again. Oh by the way, the reason they added the mechanical pump in front of the electric high pressure pump on my hp 500's was because they had vapor lock issues and the high pressure pump sucks (pardon the pun) at priming.
Last edited by supercat; 07-27-2011 at 04:26 PM.
#13
UPDATE: Took the boat out Wed night. The only changes I had made at that time were cleaning the connections with a wire brush. The boat started in the driveway and started at the ramp. We drove about 10 mins at top speed, then parked at a beach. Sat around for a couple of hours - boat started, then died. Tried to start again, and just cranked - no start. So, we sat around for about 20 more minutes with the hatch open. Tried to start again, and the engine started - no jumper cables.
So, I'm starting to the think that maybe this is vapor lock.
While having the hatch open and the blowers on, I discovered that the starboard blower was inop. Replaced that last night.
So my plan for the weekend is to run the blowers quite often prior to beaching and starting (obviously) to see if that improves my no start condition. I appreciate all of the suggestions!
.....more to come, I'm sure!
So, I'm starting to the think that maybe this is vapor lock.
While having the hatch open and the blowers on, I discovered that the starboard blower was inop. Replaced that last night.
So my plan for the weekend is to run the blowers quite often prior to beaching and starting (obviously) to see if that improves my no start condition. I appreciate all of the suggestions!
.....more to come, I'm sure!
#14
Registered
Join Date: Aug 2005
Location: sint maarten
Posts: 1,491
Likes: 0
Received 0 Likes
on
0 Posts
UPDATE: Took the boat out Wed night. The only changes I had made at that time were cleaning the connections with a wire brush. The boat started in the driveway and started at the ramp. We drove about 10 mins at top speed, then parked at a beach. Sat around for a couple of hours - boat started, then died. Tried to start again, and just cranked - no start. So, we sat around for about 20 more minutes with the hatch open. Tried to start again, and the engine started - no jumper cables.
So, I'm starting to the think that maybe this is vapor lock.
While having the hatch open and the blowers on, I discovered that the starboard blower was inop. Replaced that last night.
So my plan for the weekend is to run the blowers quite often prior to beaching and starting (obviously) to see if that improves my no start condition. I appreciate all of the suggestions!
.....more to come, I'm sure!
So, I'm starting to the think that maybe this is vapor lock.
While having the hatch open and the blowers on, I discovered that the starboard blower was inop. Replaced that last night.
So my plan for the weekend is to run the blowers quite often prior to beaching and starting (obviously) to see if that improves my no start condition. I appreciate all of the suggestions!
.....more to come, I'm sure!
#16
Post Weekend Update:
I had the boat out on Friday night, Saturday, and Sunday. As I approached our usual anchor out or beach locations, I turned the blowers on and opened the hatch about 1'. The boat started each and every time I needed it to ! I was quite happy!
Thanks for all of your help. I'd be happy to hear about the permanent solution to fix this (if there is one). If you prefer email, try easyrider1340 (@) gmail dot com
I had the boat out on Friday night, Saturday, and Sunday. As I approached our usual anchor out or beach locations, I turned the blowers on and opened the hatch about 1'. The boat started each and every time I needed it to ! I was quite happy!
Thanks for all of your help. I'd be happy to hear about the permanent solution to fix this (if there is one). If you prefer email, try easyrider1340 (@) gmail dot com