Timing on 881

Lynn Patrick

Well-known Member
Just finished rebuilding the engine: new sleeves, rings, etc. I have the timing set at 0 to start, have checked & valves are closed on compression, but all I get is backfiring thru the carb. The carb was the dirtiest I have ever seen & have cleaned it twice, but still not sure about all the passages. It's a TSX769 MS. Could the backfiring & non-running still be a carb issue? There are only 2 adjust screws, 1 top & 1 bottom. Where is a good place to start on setting those 2?
Thanks for any help!
 
(quoted from post at 16:19:37 12/05/14) Just finished rebuilding the engine: new sleeves, rings, etc. I have the timing set at 0 to start, have checked & valves are closed on compression, but all I get is backfiring thru the carb. The carb was the dirtiest I have ever seen & have cleaned it twice, but still not sure about all the passages. It's a TSX769 MS. Could the backfiring & non-running still be a carb issue? There are only 2 adjust screws, 1 top & 1 bottom. Where is a good place to start on setting those 2?
Thanks for any help!
1 zero, at TDC-comp? And wires in cap CW, 1,2,4,3?
 
Backfiring through the carb is usually a sign
of timing problems, and as JMOR said, be sure
you have the dist. installed right by being
sure you are on compression stroke and as the
timing marks align that the rotor conductor is
pointing at #1 post. He listed the firing order.
As to the carb adjustments, the one on top is
the idle needle and the one down by the float
bowl is the power needle. Turn them both in
(CW) fully to seat and then back out one turn
for initial starting. Keep in mind that the
idle is the air-adjusting type on your carb and
turning it out (CCW) will lean it, and in to
richen. The power adjustment should not be
critical for initial starting. -Will
 
Distributor is timed w/timing light on #1 wire at zero TDC while turning w/starter. Wires are new and are 1243 order. Valves are both closed on #1 at the zero mark. What am I missing???
Thanks for the responses!
 
Yup! But I had the dist out to prime the oil pump & am beginning to wonder if I have it timed 180 degrees off! Will check that in the morning!
Thanks!
 
(quoted from post at 19:04:38 12/05/14) Yup! But I had the dist out to prime the oil pump & am beginning to wonder if I have it timed 180 degrees off! Will check that in the morning!
Thanks!
n your first post, you seemed sure that valves were closed on TDC-compression, but...........if not, then simply swap wires on distributor cap as follows: swap #1 & #4(opposites) and swap #2 & #3(opposites), then give it a try.
 
OK, I win the bonehead of the year award .... again!
JMOR was right! When I pulled the distributor to prime the oil pump I must have put it back in timed 1 engine revolution off. I thought of that when I read my own post about timing it w/the timing light, not with the old fashioned finger in the spark plug hole! It starts now, but runs very rough, probably now a carb problem. That I can deal with!
Thanks for all the help!
 
Don't feel bad.
Many of us have been there, done that.
Back in the 70s I had a real nice Ford pickup with a 390 in it. Had a 2 bbl carb on it.
So I bought an intake manifold w/4bbl off a T-bird and put that in it. Had to pull the distributer to make the change.
I got it all back together and just got backfiring when I tried to start it. I checked and rechecked the timing for TWO DAYS.
Wore down the battery and starter.
No one to ask, no phone, no manual, stuck at home with an engine that wouldn't start.
I was ready to set the pu on fire.
Finally it dawned on me that the dist could be 180 out.
Switched it, burned the excess gas off the plugs and the engine fired up instantly.
That was 39 years ago.
I have NEVER made that mistake again.
You probably wont either. :)
 
Thanks UD! I overhauled my first engine ('29 Model A Ford) at 15 & am now 71. By your experience of 39 years I won't make the same mistake again until I'm 110 years old! I'll settle for that!
 

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