Please Help, cant get 2.4 XRi started...

[JimG]

Heres the story, the motor has just gone through a rebuild and some grinding. After assembly the motor fired up no problem but every now and again the idle stayed at 2000 RPM but this was happening before the rebuild just at a lower RPM. My buddy and I ran the boat in the bay for about an hour one night to test and tune, couldnt figure out the problem. Last week when searching for anything, I found that the rubber gasket on the fuel rail/injector housing or case, whatever, (laser efi) was broken and causing a serious vacuum leak. This morning I recieved the parts and reassembled the front half of the motor. I replaced all the gaskets involving anything I touched. Now the motor wont start. On initial cranking after sitting for a few minutes it fires but doesnt stay running. After that it wont fire at all. My battery is real weak and wasnt fully charged when I started this morning and my little Sears charger aint cuttin it. Could a weak battery be the cause of the problem? I have a 2.5 wheel with the 15 amp stator instead of the stock 40 amp setup. I can smell plenty of fuel and the pump is running so i'm assuming I have a good supply. I appreciate any help you guys can give, i'm really gettin bummed now after all the work thats been done. Thanks

Read my recent posts in Tech Discussion about mine. I have been told that low battery can prevent these motors from running. the battery drops way too low in voltage while cranking, and the EFI system doesn't work properly as a result.

-Chad

[JimG]

Thanks very much Chad. I just got the thing running about 10 minutes ago but it wont idle. It seems that everything is out of adjustment. From what? I dont know. I just put the battery on charge for the night and i'll go at it again tomorrow. Are there any base settings for anything on these motors besides timing? Every stop nut and screw on the throttle/timing assembly was loose and i'm having some time trying to get everything right. I dont even know how to set base timing. I guess its time to buy a repair manual, huh...

Chad, I just finished reading all the problems your having with your XRi. I got nothin compared to you. What ever happened to your cold start problem? Did you notice any difference after you adjusted the TPI?

We might be on out own. Scream and Fly's brightest and best have stopped answering any of my Laser XRi EFI questions. Here goes:

About middle af last summer, there was a fast-looking bass boat out on my lake with an Evinrude 225. He He He, spanking time! I cranked the lift down, and went to start it. Nothing. Wouldn't even fire. The plugs looked dry. I bought a new battery. OK, it cranks faster now, but it still won't start! I shot a little starting fluid into one cylinder, and it finally started up, rough at first, but OK. I eventually figured out that I could make it start cold by unplugging the ambient air temp sensor (the one in the intake manifold), then plugging it back in as it warmed up. Otherwise, it ran fine at all throttle ranges.

This spring, I checked the Throttle Position Indicator (TPI) sensor. It was mis-adjusted. I corrected it, and now the engine will fire up when it's cold, but will not idle on its own. Unplugging the air temp sensor has no effect on it.

These motors' ECU has a cold start enrichment function. It is controlled by a wire that connects to the starter solenoid. When you're cranking it, it richens the fuel injection. If I keep holding the key to start, even after the engine starts and the starter bendix disengages, it will run fine, but after I release the key, 6 seconds later it dies. I have already since re-routed this enrichment wire to the blk/yel wire that goes to the "push key to choke" switch. On these motors, that wire is cut short and taped over in the harness at the engine end. Maybe wiring it that way will allow me to "enrich at will", and avoid the hard over-rich warm starting problems I've had before.

This is from the OEM service manual:
resistances measured in ohms:
Air temp sensor should be approx. 8.5 K at 68* F, or 12K at 50*
Head temp sensor should be approx. 1.2 K at 68* F, or 2K at 50*

A higher resistance corresponds to a lower temperature, and thus a richer fuel/air mix. Disconnecting the head temp sensor supposedly makes the mix 40% richer, and disconnecting the air temp sensor makes it approx. 20% richer.

The head temp sensor is connected in parallel with two of the wires going to the TPI. To check the TPI, first disconnect the tan/blu head temp sensor wires. Turn the ignition key to ON, Jam the test leads up into the rubber connector alongside the blue and tan wires, and look for voltage. At idle throttle, it should be approx .135 volts. At WOT, it should be approx 7.46 volts.
Loosening the two screws at the sensor will allow you to rotate it slightly and re-adjust it. A low voltage will make it too lean, higher voltage will make it too rich. It should be close to .135 at idle, no more than .250 and no less than .050 according to the manual. this setting is very important. Range the throttle and watch the voltage, make sure it increases as you give it more throttle. The sensor is likely bad if it doesn't.

The MAP sensor measures vaccuum and pressure in the manifold. the sensor is actually inside the ECU. A hose goes from the ECU to the manifold. Make sure the hose isn't kinked. I've heard of that happening.

What else? Someone please help us with our motors!!

-Chad

Things to check

[RONNIE]

I told you so! Call me tommorrow at the shop and we will get you fixed up

[JimG]

Hey Chad, maybe i'll take a drive up to Michigan and we'll compare our junk!!! At least I have my buddy Ronnie here helpin me out and giving me inspirational words of wisdom like "I told you so..."

Ronnie, I thought you were still in Florida so I didnt even bother tryin to get in touch with you. Anyway, I have to try and learn this thing cause your not always around to hold my hand.

I started mine on the hose by tilting it up and putting the nosecone in a plastic basin with a hose in in, overflowing. I think the previous owner removed the thermostats, so maybe the cold hose water wakes it run too cold. I'll find out at the launch ramp this weekend.

Check all your sensors, make sure they are indicating correct resistances.
-Chad

IT RUNS! It was just the cold weather after all. On sunday, I launched in 70 degree temps. I used my newly re-wired push-key enrichment circuit to start it. Before I re-wired it, it used the start solenoid to enrich, it used to start, quit, start, quit, etc., but now, when it starts to cold-lean, I can push the key in for a moment and it keeps running!

Adjusting the TPI was really the ticket! It idles perfectly now, no stumbling or sneezing! It is set at .150 volts @ idle.

-Chad

[JimG]

Congrats Chad. I,m glad you got everything worked out. I'm gonna get together with my buddy this week hopefully to try and straighten out my problem. I did check my TPI the other day and found that I have a dead spot at around 3.5V and max voltage is around 5.03V. I can only get it to idle with the timing cranked up but I know my throttle blades are out of whack and so is everything else.