Carb issue on older car.. or?

[Guest]

I picked up a ice beater recently with some issues.. it was cheap.

Its a 87 AMC eagle .. strait 6, 4.2 liter(basicly the same as most jeep 4.0) and its carborated.

To make a long story short, the guy had a *cheap mechanic*... It ran like dirt, the timing was obviously off, the idle screw was cranked in so it wouldnt stall(yeah, a backfire is better?).. so I backed off the idle back to normal, an got it as close to in time as possible with a broken timing light(doesnt work). It idles decent and it doesnt miss...

but I didnt lose one problem... no power under load. The car wont kick down when I step on it in driving conditions, and it wont run to higher rpms when under load. It seems to be starving for gas.

The kick down linkage is connected at the throttle.. havent traced it down to the tranny but it has a serious lack of power so I havent messed around with that(least of my concerns right now).

Am I dealing with a bad carb(cant be adjusted other than idle), or am I looking at a probability of a bad valve somewhere? We dont have a lot of money to sink into a new carb if its not a high percentage chance it will fix it.

I know there are other possibilities.. fuel filters(replaing tomorrow), bad gas, etc. I just dont want to get stuck speding unneccisary cash we really dont have. Anyone around the minneapolis with a timing light?

[Macgyver55]

Oooh its been so long since I've messed with carbs (other than my own car) I don't remember what carb that vehicle has on it. Has the car been sitting for a while? It could be old gas has varnished up and plugged main jets and/or passages in the carb. Start with a fuel filter. Wouldn't hurt to throw a can of sea foam in it. The timing could be off some, but it would have to be off quite a bit to not have any power. The fact that it idles ok tells me it probably is fairly close, although the vacuum advance could be bad or sticking. (providing it has one)

I still have a good old fashined timing light and it would probably love to get used sometime but I don't live in the city anymore.

[upnorth]

One way to get your timing really close it to turn up the idle and turn the distributor until you get the motor runs at the highest yet smoothest RPM. You could just have your timeing a little bit retarded. Just be sure to put match marks on the distributor before you start so you can easily put it back to where it is. Also make sure you get it nice and warm and shut it down, let it sit for a bit and restart, cuz if you get it too far advanced you may have some issue getting it to start again.

[Guest]

This vehicle is a particular pain because its in the emission transition years, and many vehicles were going to fuel injection... So I have lots of different vaccuum lines all over the place and little egr valv looking things all over the air cleaner, 3 big lines that look similar(an size) to the crank case breather that come to the air cleaner, a couple different electrical plug in's on the carb other than choke... the thing has a O2 sensor and a leak in the exhaust...

I would hate to replace the carb just to find out I had a faulty O2 sensor. I would rather just replace it with a throttle body injection system... but finances wont allow.

This thing has a jeep power-train, ford starter, gm ignition.. and I think Osama Bin Ladin himself designed the emission system.. what the heck does it need 2 charcoal canisters for?

[Guest]

Well.. I lucked out and got the timing on by ear.. cecked it with a light this morning to find I was 1 degree off.

Its not the fuel pump, fuel filter, or a plugged cat.

I am going to drive a bunch of gas out of the car(got it with a full tank) and fill it back up with fresh gas.. If that doesnt take care of it, its getting a new carb.

[Enids Hubby]

If it idles o.k. and does not missfire at low speed and just lose power it could be plugged exhaust or a flat cam shaft . you said the converter was not plugged, did you drop the exhaust at the manifolds and try?

[DTro]

Quote:

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I am going to drive a bunch of gas out of the car(got it with a full tank) and fill it back up with fresh gas.. If that doesnt take care of it, its getting a new carb.

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Might as well try to run some Seafoam through one of the vacuum lines while your at it.

[Guest]

Endis Hubby.. I cut the exhaust off with a sawzall before the cat and drove it without exhaust.. no improvement. It was easier than trying to get off the old crusty bolts. The muffler and tail pipe are new.. only thing that could have been plugged was the cat. The ext pipe(center exaust pipe) has so many holes in it.. it wouldnt make a difference if it were plugged

Dtro.. I plan on it, I am going to put some heet(alcohol) in the tank also... if it does have moisture in there, it will help.. if it doesnt, its not going to hurt anything.

Im going to drive the gas out of it tomorrow.

[Papa Grump]

The o2 sensor could possibly be the main cause of all your issues, since that will tell the carb what and how much fuel is needed. You could probaly pick one up at the parts store for $20. The 2 charcoal canisters are fuel vapor reclamation and quite frankly you don't need them . I had a 82 Chevy pickup with all the garbage in the engine bay like that and I put on a pre-emission carb and eliminated everything else and it ran just fine. I think the carb you have is a spreadbore 2 barrel Rochester that makes a wonderfull doorstop as I've tried re-building several of them to no avail. They either work or get smashed with a hammer. Hope this helps and good luck.

[upnorth]

It has a been quite a while since I drove something of that vintage, but you may also have a severe vacumm leak. That could and would cause all sorts of problems especially your vacumm advance. Those charcoal canisters, if I am correct could be a big vacumm leak if they are bad. I would make sure that all the vacumm lines are good before you sink $$$ into a new carb.

[BIG DS]

If you can find them, all you should need is vacuum to the climate control, brake booster, and the vacuum advance. I had one of those cars about eight years ago and I remember filling a 5 gallon bucket with un-needed hose.

[IFallsRon]

Check to see if the carb is tight against the manifold. If there's a gasket, it may have a crack. I just replaced a throttle body gasket and the difference was dramatic.