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lickmychode
06-09-2003, 01:25 PM
I have a 2000 outback and it is running like S@#t, Heavy gas smell coming from exhaust, what could cause this,

Brian Raymond
06-09-2003, 09:58 PM
Is the motor a carb. model or fuel injected? How is the boat used, wakeboarding, skiing, or a little of both? If it is a carbureted version, it may be fouled plugs or incorrect float level or ruptured power valve. The carb. is a 4160 Holley. which requires bowl removal for the proper float adj. You may also have gunk build up on the needle and seat valve which control the float level, and let in unmetered fuel, a ruptured power valve will do the same. If you have not changed the plugs in the last 100hrs., or at the beginning of the season, it would be wise to do so. If the motor is fuel inj. you may have a faulty coolant temp. sensor which may tell the engine it is running cool, thus giving it more fuel. Your gauge temp. send. unit is run off of another sensor, so your analog reading may be correct, but the other sensor is telling the motor how to run. Have this checked out by a dealer, they should have you running better in no time. Brian Raymond

lickmychode
06-10-2003, 06:52 AM
It is carbed, I changed the plugs, dist. and points, I cleaned the carb pretty good, and ran sea fome through the fuel system, Do you have to jumper the ignition to set the timeing or can you just set it at idle...I have a wierd feeling this is the problem, I am not fluent with holly's so I would take it to the dealer for that but have all the tool to do anything else.

Brian Raymond
06-10-2003, 10:29 PM
With a points distributor, there is nothing to shunt out for timing issues. Timing should be @ 10deg.BTDC under 850 rpm. It sounds more like a fuel issue than a timing issue, or electrical problem. Brian Raymond

lickmychode
06-12-2003, 07:14 AM
Sorry didn't mean points cap and rotor is what I was going for

Brian Raymond
06-12-2003, 10:52 PM
You may also want to check the choke adj, if it seems to be functioning properly, I would look into a rebuild.Brian Raymond

CWS_Kahuna
06-13-2003, 03:34 PM
Check the small filters on the Carb. They are located right behind the fuel lines going into the carb (you need to use 2 wrenchs to pull this apart). Mine were totally gummed up so my friend and I tore apart the carb and cleaned it out completely. Had to buy new gaskets which cost like $8.00 and the filters to the carb were about another $8.00. I am just throwing out an idea.

Brian Raymond,
What is the proper idle RPM on a 310HP carb motor (is it 850RPM)? Also what temperture should the motor run at?

Brian Raymond
06-13-2003, 10:15 PM
The engine(@ operating temp. of 160 deg.) should idle between 700-800rpm., ideal in gear @ idle is 650-700. It is important to have the idle air bleed screws(on the sides of the main metering plate behind the primary bowl) adj. properly. A good reference is to screw them all the way in, and then back them out 2.5 turns. Carbs will differ, if you have a good ear, screw in (one side at a time) until you hear the eng. lower in rpm., then unscrew until the eng. picks up rpm., it will fall off again if you back out to far, just screw in again to max rpm. Repeat on other side. Once this is done, set your idle accordingly. The engine should normally run between 140-175deg. depending on water temp. When shut down and restarted, higher temps may first be noted. If running temps are higher, check trans. cooler on intake side for debris, also check for impellar wear. If temps. are cooler, it may be a thermostat. Brian Raymond

wdf
06-14-2003, 10:26 PM
Where is the temp sensor located? Not the analog one for the engine temp guage, but the one for the injection efi system.

Brian Raymond
06-14-2003, 11:46 PM
The Coolant Temperature Sensor(CTS) is located on the intake manifold above the #1 cyl. It is a 2 wire brass sensor(blk&yel). You can determine if this sensor is faulty by(A) taking the boat to a certified dealer, or (B) taking an ohm reading at running temp. to determine if the sensor may be open or grounded out. Brian Raymond

wdf
06-15-2003, 12:00 AM
Ar operating temp, should the sensor be closed or open circuit?

Brian Raymond
06-15-2003, 12:22 AM
It is always open(kinda,it runs off the ground circuit), but can exceed its parameters. The sensor(if bad) will always default the motor to run rich.Brian Raymond

CWS_Kahuna
06-17-2003, 10:49 AM
Thanks Brian. I got my idle set right in that range and my temp is right in there too.

wdf
06-17-2003, 09:06 PM
So, at operating temp, can one short the temp sensor lead to ground or unplug it and see if that helps, or is there a resistance value that idicates proper working?

Brian Raymond
06-17-2003, 10:40 PM
Bring the motor to operating temp(160-175deg.) on the analog gauge. Shut the motor off, and disconnect the 2 wire sensor, take a ohm reading by touching the 2 test leads to the terminals inside the sensor. As temperature increases, ohms decrease, and vice versa. there is a temp. configuration for ohms to temp., write down your findings, and contact your dealer to see if it is reading correctly. The font on the temp. gauge is to your advantage, if the gauge reads 175deg., a proper ohm reading will put you around 157deg. This is incorporated to read higher, sooner, so if an overheat happens, you will hopefully shut the motor down b4 it is toast. Brian Raymond