Driveablity Problems '86 300 I6 4-spd
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Driveablity Problems '86 300 I6 4-spd
Hello,
I've been trying to get my brother's '86 300 straight 6 running and driving decently since it's been in bad shape. The problems I'm dealing with now: leaking carb(just rebuilt, probably set the float level too high), have trouble finding the timing marks on the balancer, and while driving it doesn't have any power in 4th gear. I put the throttle to the floor and it still won't maintain speed or accelerate.
I rebuilt the carb, replaced the fuel pump, fuel tank(it was leaking), spark plugs, O2 sensor, removed the smog pump and included emissions parts, and other varies things. All of those things have improved the idle, fuel ecomony, and power somewhat but it is still has trouble holding 50-55mph in 4th gear. Is the timing off? Any suggestions on what else I should try would be greatly appreciated.
Also, while rebuilding the carb, I noticed while installing the accelerator pump that the lifter for the pump doens't move much when the throttle goes to wide open. Is this right or normal? This is the first carb I have rebuilt(I'm a EFI guy.)
Thank you for your time,
David
I've been trying to get my brother's '86 300 straight 6 running and driving decently since it's been in bad shape. The problems I'm dealing with now: leaking carb(just rebuilt, probably set the float level too high), have trouble finding the timing marks on the balancer, and while driving it doesn't have any power in 4th gear. I put the throttle to the floor and it still won't maintain speed or accelerate.
I rebuilt the carb, replaced the fuel pump, fuel tank(it was leaking), spark plugs, O2 sensor, removed the smog pump and included emissions parts, and other varies things. All of those things have improved the idle, fuel ecomony, and power somewhat but it is still has trouble holding 50-55mph in 4th gear. Is the timing off? Any suggestions on what else I should try would be greatly appreciated.
Also, while rebuilding the carb, I noticed while installing the accelerator pump that the lifter for the pump doens't move much when the throttle goes to wide open. Is this right or normal? This is the first carb I have rebuilt(I'm a EFI guy.)
Thank you for your time,
David
Last edited by rotarydave; Oct 19, 2007 at 12:20 AM.
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From: Virginia
It sounds like the engine is computer controlled. You can verify this by looking at the dist. If it has no vacuum line going to it, then it was computer controlled. I say "was", because if you took some of the sensors off, or they are not working, then the computer will not have good info to advance the timing. The computer controls the timing, there is nothing in the dist to advance it. This may be why it has no power.
If you think the computer and it's sensors are not working, and you don't want to mess with trying to get it to work, then you can go with an older dist that has a vacuum line on it, and use a dursapark II module, or you could even put an old points dist in it, and use a pertronix conversion kit to make it electronic.
If you look around in this forum a little bit, there is a guy with the same problem, but he has a v8.
If you think the computer and it's sensors are not working, and you don't want to mess with trying to get it to work, then you can go with an older dist that has a vacuum line on it, and use a dursapark II module, or you could even put an old points dist in it, and use a pertronix conversion kit to make it electronic.
If you look around in this forum a little bit, there is a guy with the same problem, but he has a v8.
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From: sunny fla sometimes windy
Did you dump the fuel from the old tank into the new one? Is the timing advancing
at all? You need to clean off the timing marks and then paint them, Some 300 had two set's of timing indicator one on one side and one on the otherside of the motor. Make
sure you are shooting off the right one!!
at all? You need to clean off the timing marks and then paint them, Some 300 had two set's of timing indicator one on one side and one on the otherside of the motor. Make
sure you are shooting off the right one!!
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Thank you for the replies. Yes, it is a feedback carb and there isn't a distributor vacuum advance. Is there an online factory shop manual somewhere online so I can test the sensors and ecu. I have a Haynes manual but it doesn't go into detail much on the feedback carbs. No, I didn't put the old fuel in the new tank. The motor does have two sets of timing indicators but I can only find one timing mark. It seems like it matches up with the timing indicator on the passenger side(the one with alot of teeth). I've cleaned the indicator off but can't see what it says.
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From: Virginia
I don't have much info on the feedback carb systems, though if it says EECIV, then that's the same computer system the efi engines use. On these, when you check the timing, you usually have to take control away from the computer, so you can set it with a light. The computer will fight you every time you try to move the timing unless you unplug it. On the EECIV systems, there is usually a single wire leaving the dist module with a plug or jumper in it called the "spout" connector. If you unplug this, it takes control away from the computer so you can set it with the light, turning the dist mechanically.
They did have EECIII systems too, so see what the radiator sitcker says about it.
They did have EECIII systems too, so see what the radiator sitcker says about it.
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It's a EEC-IV controlled engine. Fixed the flooding problem. I found a little strip of something keeping the needle from fully closing. I was able to set the timing and now I know the computer isn't advancing the timing. Guess, I be heading to the junkyard for all the Duraspark II components.
