Prostar 205 engine surge issue

[JimN]

Originally Posted by jmhjgh

Do you think a bad fuel line could stop both injectors temporarily? I would think bad lines would slowly slow the boat, and not behave like someone is turning the ignition off and on. I need to tow the boat home so we can run some more tests.

Did you check the fuel pressure? Do it at Key ON/Engine OFF, Idle, 2000 RPM and WOT. These are the recommendations from Indmar and MC. If you watch the gauge as you pass through the 3200 RPM area, it's probably dropping and this is most commonly caused by carpet fivers or other contaminants in the fuel pump screen, at the pump inlet. You don't need the boat at home for this but you can't do this on the trailer- it needs to be in the water, under normal load.

[jmhjgh]

Fuel pressure check is on my list. I do not currently own a fuel pressure gauge. I removed the pump last fall before winterizing, and the pump inlet was clean (also installed a new filter upstream of the pump). The manual valve at the tank does not have a good feel moving open to close and I probably should remove and inspect, but it doesn't seem like that would cause both injectors to drop out.

[jmhjgh]

If I were to purchase this gauge:
http://www.amazon.com/Actron-CP7817-...ressure+tester

Where exactly is this hooked up on my 96 Indmar TBI with no schraeder vavle on the fuel rail?

[JimN]

Originally Posted by jmhjgh

If I were to purchase this gauge:
http://www.amazon.com/Actron-CP7817-...ressure+tester

Where exactly is this hooked up on my 96 Indmar TBI with no schraeder vavle on the fuel rail?

You can get the same gauge at Autozone or Sears. I have the same one. It also lets you take a fuel sample, using the bleeder valve and the clear tubing.

Look at the fuel line going to the throttle body- you should see a black cap on a Shrader valve, which is just like a tire valve, on the hard fuel line (I did see that you didn't see one). Don't put the gauge on while it's running and if you put it on immediately after shutting it off, put a paper towel over the valve and release the pressure- gas will squirt out.

Where in the Midwest are you?

[jmhjgh]

I am in Minneapolis, Mn. I looked through the on-line Actron Manual, and I think I need to go in-line between the fuel filter and the fuel line to the TBI. I do not have a Shrader valve, but I will look again to make sure.

[JimN]

Originally Posted by jmhjgh

I am in Minneapolis, Mn. I looked through the on-line Actron Manual, and I think I need to go in-line between the fuel filter and the fuel line to the TBI. I do not have a Shrader valve, but I will look again to make sure.

Call the nearest dealer- if they have been an MC dealer for a long time, they might (should) have an adapter to connect inline with the fuel line, for measuring the pressure while it's running. I have one, but I'm in MKE. Otherwise, if you decide to buy one, OTC (Owatonna Tool Company) sells one. It has to be the type that works with double O-ring connections.

[jmhjgh]

New development: while out troubleshooting the boat, engine would not restart because of dead battery. Alternator was not charging. Brought it in to a rebuild shop and condenser strap broke and it took out the rotor and wiring (also burnt insulation and damaged rectifier). I am wondering if last year, it may have been overcharging at times, and this year we were seeing weird voltage spikes that would explain both injectors cutting out. Anyone think the alternator will fix my problem? Family reunion in 2 weeks, but I was not planning to drive 3 hours north to try the boat before the reunion.

Jim, I saw your note on another thread about silver soldering in a schraeder valve on a new fuel filter. Good idea, are the materials compatible? I think a co-worked has a gauge I could use if I had a schraeder valve. I think I should still check this, but I am wondering if my hopes should not be so high about the alternator?

[JimN]

Originally Posted by jmhjgh

New development: while out troubleshooting the boat, engine would not restart because of dead battery. Alternator was not charging. Brought it in to a rebuild shop and condenser strap broke and it took out the rotor and wiring (also burnt insulation and damaged rectifier). I am wondering if last year, it may have been overcharging at times, and this year we were seeing weird voltage spikes that would explain both injectors cutting out. Anyone think the alternator will fix my problem? Family reunion in 2 weeks, but I was not planning to drive 3 hours north to try the boat before the reunion.

Jim, I saw your note on another thread about silver soldering in a schraeder valve on a new fuel filter. Good idea, are the materials compatible? I think a co-worked has a gauge I could use if I had a schraeder valve. I think I should still check this, but I am wondering if my hopes should not be so high about the alternator?

Harley Davidson has silver-soldered their frames for almost 100 years, if not more. AFAIK, not a single one has failed at that joint. The other option is using a brass T block with compression fittings that fit GM fuel line. This can accept a brass or stainless Shrader valve and doesn't require any melting metal. You just need to make sure it won't leak if you decide to leave it in place.

[jmhjgh]

Any comments on the alternator possibly causing weird problems? The materials question on the schraedar valve was around if the material between the fuel filter casing and the plated schraeder valve are compatible.

[JimN]

Originally Posted by jmhjgh

Any comments on the alternator possibly causing weird problems? The materials question on the schraedar valve was around if the material between the fuel filter casing and the plated schraeder valve are compatible.

Yeah- wrong voltages will cause all kinds of problems and there's not much possibility of knowing exactly what will happen because there's the possibility of not only higher DC voltage but also AC and there's really nothing on a boat that runs on AC.

I know of people who had things silver soldered using various metals but they weren't plated. I bought one at Ace Hardware with a brass body. As long as the valve won't leak, you could mount the T block on the hard line, as I posted before. I don't know who decided to omit the valve on production boats, but it doesn't seem like a good idea, even from the standpoint of service techs having to waste time installing one. As far as the fuel line repair kits working reliably- I used one on my Chevy pickup because I couldn't remove the filter (the joys of Wisconsin Winters, you know) and it hasn't leaked. That doesn't have a Shrader valve, either and it has always annoyed me.