Shawn916

Ok. i just bought a fixer-upper out of some guys front yard for $300. Its a 1985 F150 4.9l strait 6cyl 1bl carb with a 4 speed mt. i rebuilt the carb and did a full tune-up on it and it ran great..... for a while. 2 days ago i was driving home on the freeway and every time i would give it gass it would knock lowdly so i pulled over and it started to overheat. i shut it off and towed it home. Ive done every ignition test my book has and no luck.i found out today that when i position the#1 cyl at TDC the timing mark on the balancer is at 15BTDC idk what to do. help please? oh and it will run but only with the timing mark off the BTDC side of the scale. im at a loss.

kaboom10

Sounds like the balancer timing reference mark has moved. You can replace the balancer or run it where you found it works well. Put the timing light on the #6 and see if you get the same condition. Another thing you can do is use a timing light with an adjustable pointer. You can move it to align the timing marks and see what it reads then.

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02 F-150 FX4 w/Baer rotors,carbon kevlar pads,SS lines,remote coolers/filters. IAS shocks,LiveWire tuned by me.

Shawn916

thats what i thought too. ill check in the morning. thanks :)

Shawn916

i checked with no luck. im pulling the timing cover today. yay only not.

Shawn916

i figured out why i couldnt time it right. the balancer was bad. I found this at another website that helped..... Ford in all its infinate wisdom put two sets of timing marks on the 300. There is one set on the right hand side near the top of the timing cover, these marks are cast in the cover. These naturally are the WRONG marks. On the left side of the timing cover where you can't see them are the right marks. They are on a metal plate bolted to the cover using the cover bolts. The vibration damper also has two sets of marks, wouldn't you know it! There is a large square notch , nope not the right one . There is also a very thin scribed line on the damper, yep that is the right one. .
To do this right, slide under the engine and clean off the thin scribe line and paint it white and while you are under there you can see the bolted on timing mark on the cover there is a large triangle cut in the plate , that is 10 degrees before TDC the correct setting .Pull your distributor cap and crank the engine untill the rotor points at number one cyl on the cap.Then see if you can see the alignment of the timing mark on the damper some how and the mark on the bolt on plate, its easier when the engine isn't running and you can stick your head in there without loosing half of it. Your timing marks should be some where near each other. Crank the engine to align the 0 degree mark and the mark on the damper, don't worry about the distributor position. Just line up the marks. Then go to the right side of the cover with the cast in marks( that you can see) and mark the damper with white somthing, paint even whiteout works.Now you have a new timing mark that you can see. Pull the spout, yes it is in the same harness as the distributor connector, its a gray jumper.Put the cap back on. Start the engine and use your new marks to set the timing at 10Degrees before TDC.
Of course this only works if your cover has the cast in marks, I have a 90 and it has the marks. I have just finished assembling the engine and found out that the engine was set using the damper line and the cast in marks. I figure the engine was running 40 degrees retarded, but MAN did ever start quick in any weather with any oil at any temp.
There are other way to do this but it takes too long to describe them here.Sorry I almost forgot. When you mark the damper with the new mark it should be marked the same as the left side original, i.e.--
if the original marks are aligned at 0 you should paint your new mark to align at 0 also, if the original is at say 6 your new mark should be painted to be in line with 6 on the cast marks and so on.

Shawn916

i had timing trouble kuz my balancer was bad. i got a new one and now its perfectly timed but when i give it gas it chugs through the carb like theres a valve open. the oil is almost on the H on the guage. could it be stuck lifters? idk. i just did an oil change a week ago to see if it would help but it didnt.