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pilot02
07-12-2007, 06:11 PM
I need some info. One of the boats I ski behind 1996 Prostar 190 with the 328hp LT1 died on saturday. My friend was pulling me through the course and the boat started having an intermittent hesitation as if it had a slight miss. We ran 2 passes through and it seemed to be ok then on the third it significantly lost power as we passed through the 55m bouys so he dropped me and we got in my boat to finish the set out. Well, I had people that had to be home early with me so we left and got back to the dock and I get a call that the boat died mid channel on the way back in and wouldn't restart. Originally, I thought the miss might be an ignition issue but now with it not restarting I'm thinking it's most likely fuel. No check engine light illumination and there's not a boat shop in the area this thing is located with the proper diagnostic equipment. So my questions are.
1) How to go about checking the codes on this boat without a scan tool.

2) Procedure for testing the fuel pump... pressures etc. on this year model with this engine.

3) Any other suggestions.

I plan to take a timing light and fuel pressure gauge down this weekend to verify that we still are getting spark and to check fuel pressures and then go from there. My understanding is that I'll have to remove the "corvette" covers to access the fuel rail. Is there anything else I need to know, special tools etc. since I'll be 75 miles from my tools.

Thanks!

Andyg
07-12-2007, 06:35 PM
There is a valve on the fuel rail, if I remember correctly it is on the starboard rear of the fuel rail. There is a black screw on cover, looks like a valve stem cover that comes off and then you can hook your fuel pressure gage to that. If you do a search on hear I think I remember seeing the proper fuel pressure for an LT-1

Also check the inlet screen on the bottom of the fuel pump to see if it has a blockage.

I would replace your inline fuel filter that is after the pump also. You can pick one up at any local auto store by bringing it in with you or writing the numbers off of it.


You failure sounds a lot like when my fuel pump went out on my 97 with the LT-1. It didn't die completely though.

I would also recommend to check all of your electrical connections to make sure they are tight and clean of corrosion.

MYMC
07-12-2007, 06:42 PM
I need some info. One of the boats I ski behind 1996 Prostar 190 with the 328hp LT1 died on saturday. My friend was pulling me through the course and the boat started having an intermittent hesitation as if it had a slight miss. We ran 2 passes through and it seemed to be ok then on the third it significantly lost power as we passed through the 55m bouys so he dropped me and we got in my boat to finish the set out. Well, I had people that had to be home early with me so we left and got back to the dock and I get a call that the boat died mid channel on the way back in and wouldn't restart. Originally, I thought the miss might be an ignition issue but now with it not restarting I'm thinking it's most likely fuel. No check engine light illumination and there's not a boat shop in the area this thing is located with the proper diagnostic equipment. So my questions are.
1) How to go about checking the codes on this boat without a scan tool.

2) Procedure for testing the fuel pump... pressures etc. on this year model with this engine.

3) Any other suggestions.

I plan to take a timing light and fuel pressure gauge down this weekend to verify that we still are getting spark and to check fuel pressures and then go from there. My understanding is that I'll have to remove the "corvette" covers to access the fuel rail. Is there anything else I need to know, special tools etc. since I'll be 75 miles from my tools.

Thanks!
1) You can't check the codes without a Tech1 or Diacom.
2) Andy is correct on the fuel pressure test port...remember this is high pressure so you'll need an actual FI tester to screw onto the test port.
3) Don't bother checking the timing you can't adjust it. If you are looking for spark, ground a plug wire or use and HEI tester.

Sounds like a fuel pump.

pilot02
07-12-2007, 07:39 PM
1) You can't check the codes without a Tech1 or Diacom.
2) Andy is correct on the fuel pressure test port...remember this is high pressure so you'll need an actual FI tester to screw onto the test port.
3) Don't bother checking the timing you can't adjust it. If you are looking for spark, ground a plug wire or use and HEI tester.

Sounds like a fuel pump.

Mike
I agree, I think based on what I've seen on this board it's likely the pump but I'd also thought I'd seen somewhere that you could ground a terminal on the diagnostic connector and count the flashes like you can on some cars of the same era.

Is that pump a dealer only item and if so, how long to get one? I won't be the person actually purchasing any parts as it's not my boat but I will make suggestions....

Andyg
07-12-2007, 09:58 PM
I had two fuel pumps go on my 97 LT-1. The first pump I replaced with one from Skidim. It came with the wrong fittings though so I had to swap them out from the original. That new fuel pump died within a year, probably from me running it dry at some point. The second one I bought from the local dealer. That one is still in the boat 5 years later and running great. I don't know if they are at all different or if I fixed another underlying cause. The biggest difference was the skidim pump cost about 60% of the pump the dealer sold me.

MYMC
07-13-2007, 10:51 AM
Mike
I agree, I think based on what I've seen on this board it's likely the pump but I'd also thought I'd seen somewhere that you could ground a terminal on the diagnostic connector and count the flashes like you can on some cars of the same era.

Is that pump a dealer only item and if so, how long to get one? I won't be the person actually purchasing any parts as it's not my boat but I will make suggestions....
Before OBDII and later generation GM diagnostics you could ground A & B with a paperclip and count the flashes on the check engine light for set codes...never worked in a boat since up until 2007 they were not equipped for closed loop operation.

I'd buy the pump from a dealer like me on line :D but there are multiple sources for this as Andy has outlined above.

tommcat
07-13-2007, 02:28 PM
the previous owners of my boat went through a bunch of fuel pumps. evident by the 3 spares in the glove box when i got it. for the first year i had problems with the pump screen getting plugged with black goo intermittently. i traced the problem to the rubber fuel line coming apart inside. after some research i found that fuel with ethanol(which we run here) will eat away rubber lines and some epoxy and sealers used in earlier boats. it's one of the great side effects of ethanol.
i replaced my fuel lines and have had no more problems since.

bowtie355
07-13-2007, 03:10 PM
1997 LT1 will have OBD2 PCM. 1995 LT1 was the last year for OBD1 PCM's. X-Ray makes a very affordable diagnostics tool which will allow you to monitor the engine sensors while running.
You can isolate a fuel issue by hooking up a fuel pressure gauge to the sharder valve. Jegs sell a fuel pressure gauge along with an adapter that will screw onto the sharder valve.
You should hear the fuel pump when put the ignition in run. It usually will run for 10 seconds to build pressure and then shut off by the PCM.

http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_761455_-1_11175

pilot02
07-15-2007, 11:46 AM
OK, looked at the boat yesterday. Hooked up a fuel pressure tester and had an initial pressure of a few pounds. Turning the key on pump would run for about 2 seconds and build pressure albeit slowly. Typically 2-3psi increase each time the switch was cycled with leaving about 10 seconds in between tries. Max pressure obtainable was 24psi. Boat would start and immediately die with pressure dropping to about 10 psi. Ignition appeared normal so sounds like fuel pump to me. Mike, anyone else, can ya'll confirm? Also this boat has 2 fuel filter's, one right before the fuel rail, and another, just outside the tank. Is that the typical setup? The filter outside the tank was not a screw on fitting type.

Thanks all!

Mike, PM me a price and I'll pass it on...

bowtie355
07-16-2007, 12:50 AM
OK, looked at the boat yesterday. Hooked up a fuel pressure tester and had an initial pressure of a few pounds. Turning the key on pump would run for about 2 seconds and build pressure albeit slowly. Typically 2-3psi increase each time the switch was cycled with leaving about 10 seconds in between tries. Max pressure obtainable was 24psi. Boat would start and immediately die with pressure dropping to about 10 psi. Ignition appeared normal so sounds like fuel pump to me. Mike, anyone else, can ya'll confirm? Also this boat has 2 fuel filter's, one right before the fuel rail, and another, just outside the tank. Is that the typical setup? The filter outside the tank was not a screw on fitting type.

Thanks all!

Mike, PM me a price and I'll pass it on...


You should always have at least 24LBS pressure, even if the engine dies. The fuel line should hold the pressure for sometime. Sounds like a clogged fuel line or bad pump.
Dan

Thrall
07-16-2007, 10:22 AM
2 filters is not OEM, at least on my boat. It only has one filter on the back of the engine. Shouldn't hurt the fuel pump if the filter before the pump is clean though.

tommcat
07-16-2007, 12:58 PM
2 filters is not OEM, at least on my boat. It only has one filter on the back of the engine. Shouldn't hurt the fuel pump if the filter before the pump is clean though.Mine also had just one filter, engine mounted. i did put on another before the pump though, a clear one so i could see if i was still having any fuel line issues.

bowtie355
07-16-2007, 03:31 PM
It's doesn't take very much interruption of fuel pressure for port injection to fail.

alpine740
07-17-2007, 10:10 PM
My '98 Prostar 190 has two filters; one above the tank upstream of the fuel pump and one above the engine downstream of the fuel pump. There is a removeable deckplate that provides visual access to the filter above the tank.

pilot02
07-21-2007, 12:50 PM
My '98 Prostar 190 has two filters; one above the tank upstream of the fuel pump and one above the engine downstream of the fuel pump. There is a removeable deckplate that provides visual access to the filter above the tank.

This is the setup he had.. He received the new pump and new fuel sending unit from Mike yesterday and it's been installed with new filter's and I'm told is running great. Fuel pressure is higher than I'd have expected 40psi but that matches the number an indmar tech gave for that engine. Skiing in 2 hrs so we'll see....:D :D :D