Have a987 E350 Motorhome with the Carburated 460. This motor has always been a strong engine and always ran strong...until recently. All of sudden it will cut out on me driving around town...just stall, no warning. It would start right back up, and I can get home. ISo I kind of figured it may be a fuel related issue so I changed the fuel filter near the carb. and cleaned the carb with Berryman's. It has not stalled when I just drive it a small amount, but it is really rough idling and in gear. Exhaust smells like gas.
So, round two. The RV is new to me last summer. So I decided to due a complete tuneup, rotor, dist. cap, wires and spark plugs. All of these items looked original. So I gap'ed the plugs and replace everything. Started great, but then went back to rough idling and sputter and when I rev. in Drive, it sort of backfires a little?
So I am stuck. Whats next. I did the above as it probably needed anyway. Other observations, sparks plugs looked fine, but had a lot of gas on them. Seems as it is running rich. There appears to be fuel filter of some sort in-line under the drivers side. it looks like a can and is an AC delco part. I can't find it in my Chiltons book. Only fuel filter is referenced near the carb and the only fuel pump is electronic in the tank on the carb model. What is the other "filter". No electricity to it just in-line with fuel line. It appears tob e soem sort of filter?
Any other suggestions, bad carb.? It is the original 2 barrel Holley.
Did you check the timing? If it's over-advanced too much it will cause it to backfire.
There could be several things wrong that would cause the engine to run rich and idle poorly.
1. Stuck Choke
2. Misadjusted idle mixture
3. Ignition Coil putting out low voltage
4. Incorrect spark timing (again)
If the motorhome sat for awhile with gas in the carb then it could have left a coat of varnish in it that would cause it to run erracticly. Also, because of age, something as simple as hitting a bump in the road could have shaken somthing loose (ex. coil wire, gas deposits...) that could cause problems.
It could also be more in depth problems with the carburateor but I can't troubleshoot anything else without additional information.
1987 460 class c motorhome
<HR style="COLOR: #666666" SIZE=1>Did you ever solve the stalling problems on your motorhome? I have the same year and engine and it is doing exactly what you described. Ford has been no help. I could use help fast because I am to use the motorhome for christmas 2005. Thanks
We just inherited a 1984 27' Jayco (E-series chassis, 460/C6) from my wife's parents and it is having similar problems. Part of the reason they were willing to give it up is because their mechanic could not figure out the problem. He had rebuilt the carb and changed the filter. The issue now is that no fuel is getting to the carb.
I haven't had time to go up and really tear into it yet. When I did look at it, I noticed that it also had a filter down along the frame rail, and it had not been replaced. I also saw that they had about 2 dozen clothes pins on the fuel line, so I know that vapor lock has been a problem. What puzzles me is that there are electric pumps in the tanks, so vapor lock really shouldn't be an issue. From the few minutes that I did get to look, I think my problem is that the pumps are not working (I did check the inertia switch to make sure it was not tripped).
I rebuilt the carb. That didn't fix the problem. Replace the fuel pump relay. Not fixed. New coil. Not fixed. I have replace the electronic ignition mounted on the finder well. That might have don't it. Not sure I have to drive some more. Were was the inertia switch. My coach says their is one, but I haven't found it? I'll repost if the electronic ignition seems to do the trick. I used a napa ignition part.
On the 1987 E350 it is mounted on the inside of the front engine compartment wall on the driver's side of the car it is one relay with black and green halfs that don't come apart. It has 4 blades on the Ford part. The Napa replament has 5 blades but seems to work. If you have a house battery on that side it is probally hidden infont of the battery. The bracket is one screw and you might need it for the new relay.
I have the new type filter. As I said earlier, I replaced the ignition module on the fender well and the motorhome has run fine for over 250 miles. Out of curiosity I took the old module to Auto Zone to have them test it because Ford couldn't test it. It failed the 1st time and the test guy fiddled with the modules connection and retested. It passed. He tested again and it passed. I noticed that the electrical grease that they put on the connectors was dried out. I don't know but I'm guessing that with the dried electrical grease and engine compartment heat that the connection from the module was not conduting consistantly. That's a guess only. It still could have been the module which I replace. I hope to put another 300 or 400 miles on it this week to see if it hicups at all.