Good Morning Folks,
Before you go commenting about a carb being mis-adjusted, etc lemme esplain. I've only had this truck a few months and really only had it on the road and working it for the past 2 weeks. Prior it's been on the road but starter issues left me stranded or in the driveway.

Anyway, since I got the vehicle I replaced the fuel filter, rebuild/refreshed the carb, replaced the entire cooling system sans heater core and replaced the brake booster/master cylinder. Not that this has much to do with anything but I just wanted to make note.

SO last week when I fueled up I put a can of sea foam in the tank. I've always been skeptical of these kinds of products BUT i have read alot lately about seafoam helping clean things out. Since then I feel as if the truck has been ideling rougher. I mean it is a 158k mile old lady but prior to adding the can to the tank it ran pretty dang smooth at 600 rpm. Now i can feel an intermittent vibration/misfire at low idle that wasn't there a few days ago.

One thing I should note...I did check the oil level the other day and it wasn't even reading on the dipstick. I topped it off and off I went. This ideling roughness didn't start for a few days afterwards. When I say rough I just mean its running as if every so many revolutions, one cylinder is misfiring. I don't want to call it a misfire exactly as it doesn't sound like that. It's hard to explain but I hope someone might be able to interpret my description!

Any input is much appreciated!
Thanks,
Al

 

Have you replaced the fuel filter since you put the Seafoam in? It's very possible that Seafoam dislodged dirt in your fuel system that's now residing in the fuel filter.

 

^ That sounds like a very reasonable explanation. Is it more like a sudden shake of the motor (almost feels like a miss)?

That Seafoam really works great. I always had a little lifter tick on the highway in the '86, so I dumped 3/4 can in the oil. After about five miles, it already started to go away. Now after approx. 100 miles, it's completely gone. Great stuff IMO.

 

I second what they've said.

The seafoam has probably knocked something loose that has gone through your carburetor. It probably wouldn't hurt to open up the bowl on your carb and blow things out with some carb cleaner and add an inline fuel filter.

Have you tried inducting the seamfoam through the PCV valve? You'll need to change your spark plugs afterwards, but it's supposed to be great at cleaning out the intake, cats, the valves, the PCV port and PCV valve, etc.

 

I have not changed the fuel filter. I had thought about maybe gunk in the fuel tank loosened up and clogged up the sock (I always have to this worst case) but oversaw the fuel filter...DUH! The fuel filter is just an aftermarket and clear so I can at least see what's going on.

Now why do you have to change the plugs after seafoaming the fuel? I thought the stuff was meant to clean carbon deposits? LOL I haven't changed the plugs since I got the truck and the PO claimed he did but for my own peace of mind I probably should. Who knows if the PO even gapped the plugs properly.

On second thought as well as rough running intermittently, it's also harder to start. I used to be able to turn the key one short click and that pig fired right up (warm of course). Now I have to pump the gas as i'm cranking a warm engine. Yeah this is definately sounding carb/fuel related.

Any other thoughts, ideas? Thanks for your input...It is much appreciated.