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View Full Version : Question about 2.8 V6 carb...



Grumpiebill
03-12-2014, 11:30 AM
I just purchased my 2nd Jeep ever last week it's a 1986 Comanche 2.8 V6 auto 2wd. When I was looking at buying it I drove around the block at not much speed. 25-30 mph. The seats weren't bolted down and no lights out back. Seemed to run good. Engine has been rebuilt by a Napa shop and sounds real good internally. But after negotiating a price and driving home it fell on its face at 30-35 mph. Thought was running out of gas. Got it to a station put $40 in it. Samething. Been tinkering with vacuum hoses and have noticed this is not a feedback carb. No t.p.s. And no metering solenoid. Did find a leaky coil wire but that repair didn't help either. Anyone have any experience with this carb? Engine just falls flat, wants to stall and pumping the throttle has no effect or worsens the condition and stalls...new here, I appreciate any help...

wayoflife
03-12-2014, 02:49 PM
Sorry, I have no experience with the 2.8L V6. Are you sure the problem is with the carb?

Rccrwlr
03-12-2014, 03:24 PM
Any thought to a fuel filter clog? Had an issue that when I was going faster and requiring more fuel the clog would suck up against the filter and block the gas. This is on a diff motor but sounds similar

Grumpiebill
03-12-2014, 11:41 PM
Yes rccrwlr, that is a possibity. Will look into that. No, not 100% sure it's a fuel issue. Just strikes me as odd that this '86 doesn't have a feedback carb on it...

Grumpiebill
03-13-2014, 12:11 AM
Sorry, I just realized I failed to add that the engine cranks for an exceptionally long time before it starts. Seems to indicate carb might be leaking down...is this common with Rochester r22se?

Grumpiebill
03-14-2014, 02:26 AM
Spent most of the day working on this carb. It's a rochester varajet2. Had sludge in the bowl from sitting I suspect. Cleaned it up. Making sure all internal ports are open. Got it back together this afternoon. Made a big improvement. Still having issues with the secondary. Driving it after reinstalling the carb it was good up to 40-45 mph. Falls flat and stalls. The vacuum servo is bad. Probably a ruptured diaphragm. I used a 1/8 drill bit pushed into a vacuum hose so it wouldn't fall in to hold open the secondary air plate and used a zip tie to hold the plate in position then removed the drill bit. Seemed to help. Also found ignition timing to far advanced. Set to 12 deg. Btdc...wish me luck. It's been a long day.