'85 720 dies intermittently

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Radio Ron
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'85 720 dies intermittently

Postby Radio Ron » Thu Dec 25, 2008 9:59 pm

I have a 1985 Nissan pickup that has a very intermittent problem.It seems to be carb icing but none of the normal fixes help.Just to describe a typical drive, yesterday morning I left home at about9am, it was in the mid 30s. I drove about 20 miles, half of it on the interstatecrusing a 65mph with no probelm, after exiting the interstate and driving about 2 miles the motorlost power and died. I sat about 1 minute and it started right up and ran finefor another couple of miles and died again. This went on for the rest of the drive,After setting for a couple of hours I drove it about 15 miles, made a 5 minute stopwhen I started again it went about 1/2 mile and died. Started right up after about1 minute and drove another 15 miles home with no trouble.

It was in the shop a couple of weeks ago for 5 days, they changed the fuel filterand the distributor cap and rotor button.The warm air pipe from the exhaust to the intake is in place and the damperin the aircleaner snout is working.

It has never failed to restart.

Does anyone have any ideas for what I should do next, beside drive it to the junk yard???

If I take to a regular garage they''''ll drive it around to block with no problem and sayit runs fine...


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breadbox
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Re: '85 720 dies intermittently (Radio Ron)

Postby breadbox » Fri Dec 26, 2008 9:28 am

If someone messed with a fuel part and then it has trouble running, I'd look over my fuel system and see that everything is right.

You could seafoam and see if it helps. It helped my truck run at lower rpms but I think I have a vacuum leak so it ran kinda crappy at low idle.

Also I am curious how important is the intake to exhaust "warm air pipe" as far as running smoothly.

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Radio Ron
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Re: '85 720 dies intermittently (breadbox)

Postby Radio Ron » Fri Dec 26, 2008 12:45 pm

It runs fine until the engine stalls. Wait a minute or so and it'll start up and run just fine until it stalls the next time.The only thing that was done to the fuel system is the fuel filter was changed.

I guess I'm out of the loop a little, what's seafoam, and what does it do???

Ron

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phlebmaster
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Re: '85 720 dies intermittently (Radio Ron)

Postby phlebmaster » Fri Dec 26, 2008 12:55 pm

Radio Ron wrote:I guess I'm out of the loop a little, what's seafoam, and what does it do???

Ron
Seafoam is a gasoline additive/cleaner. Works good.

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PEZi
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Re: '85 720 dies intermittently (breadbox)

Postby PEZi » Thu Jan 01, 2009 4:35 pm

breadbox wrote:
Also I am curious how important is the intake to exhaust "warm air pipe" as far as running smoothly.
i cut my air box so that is just the filter with a lid.... no snorkel at all so i deleted the "warm air pipe"

it runs amazingly better but has issues warming up but that was easily fixed by putting a blocker in front of the radiator (cardboard works fine). the downside to this is that i have various sizes that i have to put in for different temperatures and highway vs city driving accordingly. i'm looking into an electric fan as well so that it wont spin while its warming up which should help a bit. i'd suggest taking the pipe out because it definately helped me out as far as smooth running... but basically if making a bunch of different radiator blockers and getting in and out to switch them doesn't sound fun leave it in


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