Today was the day, first start for our 1919 Speedster chassis. Double checked all fluids and connections, topped up the coolant and added a bit of gas to my temporary gas tank. Set the key to BAT, spark retarded, gas cracked,
GAV 1 1/2 turns open, and cranked her over.
Cranked OK, but no fire.
We're running a Texas T Parts distributor, no water pump, newly rebuilt engine.
Checked spark from the center wire to a head bolt, and had good spark. Gave it a little more gas, choked a bit, and tried it again and this time got persistent backfires through the exhaust.
Need to let the battery recharge, so am asking for suggestions from the board. I think we're close, but I'm missing something. Timing off?
First/easiest guess as you say timing is off.
sounds like timing's off somewhere
spark just after TDC?
cam gear and crank gear timed?
valve lash correct?
First is most likely, and Quick compression check will rule out last two to a great extent
I went through this exact problem a couple weeks ago with a freshly rebuilt 1914 engine. I found that I needed to pull the spark down a notch or two farther and pull the throttle lever down a bit more, too. It seemed as though gas was not entering the cylinders to fire. Not a pop. Then I sprayed some starting fluid in #1 cylinder and replaced the plug. It started on the second pull! And even better, the engine continued to run because gas was now being sucked up into the cylinders. I posted this experience a day later and got mixed agreement postings. But it worked for me. I had worn myself out for two days prior, hand cranking and choking, allowing time for any excess gas to evaporate. Nothing. I'm convinced that the few blasts of starter fluid in #1 cylinder did the trick. Try that before you ruin your elbow hand cranking without success.
1 1/2 turns open on the gas valve seems a little
to much to me. Try about a 3/4 turn
One of my favorite tricks on myself is to set the timing on top-dead-center.... EXHAUST. Are you sure that when you set your timing you were on the compression stroke?
I'm with everyone else. Check the timing. Also check the firing order. From memory it is 1-3-4-2. Someone correct me if I am wrong.
Other than that, the mixture could be way off. A distributor is more touchy with regards to mixture than coils. It is easy to flood the engine. Look at the plugs. Are they wet?
Neil - 1243 I believe,.....
Double check your wiring especially between the plugs, coils and timer. Jim Patrick
1,3,4,2, according to the wiring diagram...
Jim - I'm pretty sure you're cranking the engine "backwards" (if that were possible) to get that firing order,........harold
Jim, Look at the timer on the schematic you posted. The brush turns counter clock wise looking from the front of the engine. 1-2-4-3
Always remember the little rhyme:
1243 that's the rule for the Model T. 1342 and it's over the fender with YOU!
Works every time.
Oops. My bad.
When trying to remember the Model T and Model A firing order, it's just as easy to envision the crankshaft design. When #2 piston is at the highest point in its travel, so is #3. If #2 is in the firing position, obviously #3 is not going to fire next because it will revolve back down with #2 (after it fires) as #4 comes into firing sequence. Then #3 swings back up into firing sequence in the compression stroke. The design of the crankshaft therefore precludes a 1-2-3-4 firing order. It MUST be 1-2-4-3, as dictated by the crankshaft's design
With 1-4 paired and 2-3 paired, like most in-line 4 cylinder 4 strokes, there are two possible firing orders: 1-2-4-3 and 1-3-4-2. The camshaft will determine which is correct for any given engine. T's are indeed 1-2-4-3, but I would venture to guess it is in the minority, with most being 1-3-4-2.
The most common mistake is to have #1 firing when the piston is up but on the exhaust stroke. The engine will pop and snort when you try to start it but won't run because as soon as it fires it is blowing the intake charge back instead of pulling it in to the next cylinder and the next cylinder doesn't have a power stroke. This is very common with timer rollers and cams that have the hole drilled all the way through but is easy to do with distributors, too.
I'm thinking I may have timed the engine on the exhaust stroke based on several comments above and will be checking that out before trying again this weekend. Discovered I blew out the muffler on one of the backfires.
The forum is such a marvelous place to get advice.
We had this system that was referred to as static timing. It was used when the distributor was pulled for whatever reason and did have the advantage of timing marks on "Modern" engines. You'd pull #1 plug and crank until you got compression (thumb over the hole). Then by hand you'd pull the motor over until the timing marks were aligned (what ever it called for. 10 deg. for instance). Install & wire up the dist and hook up a test lamp to the points. Ignition on. Rotate the dist body in the direction of it's running rotation until the lamp came on then rotate it back until the lamp just went out & lock it up. Where ever the rotor pointed became #1 and if you didn't take the wires off the cap you had an idea where #1 was anyway and set it with the rotor close to that position. It was so damn accurate re-setting was usually not necessary and it guaranteed a start because it was so close to right. You could do something like this with a T but the piston position becomes critical as there are no timing marks to align.
Just bumping this to the top to see if Wayne will reply with his solution.
Sounds like it was timed 180 degrees off.
Update -- Success!
I spent Sunday retiming the ignition and checking everything else, including adding some hose clamps to my jury rigged gas line. Pretty sure the timing was off 180 degrees.
Pulled her out of the garage, put some gas in the little tank, cranked her over a couple times with the choke out to prime, then turned on the ignition and she fired. A little more throttle, and she started and ran. Spark down, and turned in the mixture to about 3/4 turn and she smoothed out real nice. Turned her off for a few minutes, then restarted and let her run until the radiator started steaming a little, maybe 10 min. then shut down again. No bad noises or smells, just a little bit of oil burning off the exhaust.
My plan is to start her and let her run a little longer each day checking that the generator is charging OK, then getting her up on jack stands to check the bands and the Warford. Once everything checks out I'll disconnect everything, take off my temporary firewall and start fitting the fenders and body.
WOO WOO WOO great job.
Just started a rebuilt T with new SCAT crank, con rods, alum. pistons, rings, Valves etc. Found I had to play the choke to keep it running and It was tight. However a full battery is essential on coils,(yours is a distributer so don't think that is as important) carbureter needle at 7/8 to 1 turn from the bottom ( ie gently turn to right until it beds,then anticlockwise) NOTE gently as the needle is quite delicate and can be ruined.
Also make sure the carby and intake is tight on good gaskets and no air is being sucked in except through the carby. cheers
OOps too late!!
Update 2 - Break-in
Been running the chassis a bit more each day and she's loosening up, cranks over a bit easier each time. Generator's charging OK. This morning I put her up on jackstands to check out the transmission and Warford. Low gear and Reverse worked well, free neutral, shifted into high with no problems, and the Warford shifted between low, high, and neutral.
My daughter will be home for July 4th, so I'll keep running her until she can see her car run, then I'll pull things down to fit the body and fenders.
When I was installing the Bendix cover I thought I had dropped one of the small bolts into the openning. I could never find it and since there's no magneto coils on the flywheel to get chewed up, I finally just buttoned everything back up. I can't hear anything rattling around while she's running, so maybe I imagined it or its hiding somewhere non-moving.
You may be Lucky and find the small bolt when you drain the oil. Normally there is a plate with a hole under in the oil pan just above the drain plug to separate the dirt from the oil, see photos.