350 bored over 60 compcam and hirise intake edelbrock 600cfm electric choke, th350 2800 stall
so i pulled 2 spark plugs and one was wet and had oil on the threads it was number 1
so i pulled number 2 and it was dry and looked ok some one said i was running rich and needed to down jet the carb does seem to have some white smoke at idle when car was wormed up. this is a rebuilt engine trying to find out if they broke it in correctly or not
i have had alot of luck from u guys so this is were im turning to thanks
My gut feeling is that the engine has problems. Remove all spark plugs, wedge the throttle plate open, and run a compression test on all cylinders.
Post any results for discussion.
While the plugs are out you might consider installing the correct plugs in the motor and get rid of those trick plugs that will accomplish nothing.
Back in the early 1960s, I replaced the spark plugs in my 1954 Buick with sparks I bought from Western Auto that had two side electrodes. I had a continual problem with these plugs fouling out. I replaced them with AC 45 that were specified for the car and had no more problems. I cleaned up the Western Auto dual electrode plugs and tried them in the lawnmower. They didn’t work very well there, either.
Do the compresssion test to be sure that the engine has proper compression, then throw away those trick spark plugs.
That chart is excellent but they did not include a flooded plug. Of course the black sooty plug is the result of excessively rich combustion but an engine that has been running well but suddenly fails to start due to flooding will result in a clean but wet plug.
thanks for all the responces i will do a compression test, and as for the plugs i need to find short plugs due to the headder clearence but the guy i had got the car from said he rain those becouse he didnt no what to gap the plugs at, but i do agree with everyone on the plugs and they will be hitting the trash, should a run the engine first then take down each plug result for the cylinder or just go ahead and toss them run new plugs then check those, again thanks for all the help so farr i will be doing a compression test and give the results.
The carburetor settings are going to affect all cylinders pretty much the same. You are not going to get one plug fouled and the next one normal because of the jetting.
The plug in image 845 is oil fouled. The rings were either installed incorrectly or it has not been broken in yet.
Check all the plugs. If this engine is installed in something, take it out and do a couple of hard accelerations on high gear from 30 to 50 mph. Do not push the throttle to the point that it downshifts. 10 cycles of this would break in any rings. If the plug continues to foul, the engine will have to be torn down again.
The white smoke bothers me the most though. That could indicate a crack in the block or head or a bad head gasket. It won’t be in the cylinder this plug came from, but if you find a plug that looks like it has been sand blasted or steam cleaned, or the ceramic on the center electrode is cracked or missing, that would be the one.
As for a plug and gap recommendation, I would install a set of ACDelco R45TS copper cores gapped at .045". This combo has worked well with every Chevy 350 I have had, and is the setup of choice of all the Chevy nuts and gurus I have known. If the junk Bosch multi-prong things fit with the headers (I swear, those things look like they are designed to foul out the center electrode, completely snuffing out the spark), the ACDelco plugs will fit. If the installation clearance of your current plugs bothers you, you could order a set of header plugs from Summit Racing. I believe they are made by Accel, but do not buy them expecting performance gains. They are only good for keeping your plug wires from getting burned in extremely tight situations, as they are about 3/8" shorter than standard plugs.
The readings are all a bit low but Number 1 is horrible. If the reading jumped up to 156 during the wet test then that’s a piston ring problem and from the sound of things Number 7 may also have a serious issue; maybe worse than Number 1.
Engine break-in is irrelevant at this point so I think you need to start consdidering an engine rebuild or replacement.
As to whether this engine was rebuilt, rebuilt properly, broken in properly, and so on I have no idea but a reasonably safe bet would be that whoever told you it was rebuilt knows full well it had problems before you bought it.