VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1912-1928 Timing Gear

How do you time the Distributor to a 1928 engine Chev? It back fires thru the carb and won't turn over! We need help!

Could timing be 180 degrees off? Make sure that at the timing mark cylinder #1 is firing at the end of the compression stroke.

Hi Touring Darla,

Give us a hand on this one. Can't give you any advice until we know more specifics about the problem. Define "won't turn over". Has the engine been running and now the problem has occured? Has the distributor been removed and replaced? Do you have the owners/repair manual? Have the timing gears been replaced? Aftermarket gears are often mis-marked and give mechanics searious headaches. Not being critical, but we need more info in order to provide intellegent information.

No, the timing degree isn't off. This engine sat years in Texas, in a touring car and was covered with 2 inches of Texas dirt and stuff. It was bought to Ohio where my Dad is trying to totally restore the car ground up. The x-owner thinks it ran maybe 5 years ago but not sure. The timing gears has not been replaced. The engine was taken totally apart and 1 oil ring was broken and replaced. The distributor was removed and cleaned then replaced. He was a poor copy of a owner's manual but it doesn't appear to be helping him much. When he tries to start it, it throws gas thru the carb and back fires as well. It appears to be firing before it suppose to(pre-ingintion).

Darla, please have your Dad purchase a 1928 repair manual (shop Manual) Hemmings Motor news Magazine lists several vendors, also you can order them on line from the Filling Station, Chevys of the 40's Check out the Vendors section of this site. To time the distributor check the repair manual.(if he is not a member of VCCA he may want to check into joining)You get a great magazine each month (the Generator & Distributor)and leads to local clubs (Regions) for a paultry sum. Go to www.vcca.org for details!

What I always do is pull #1 plug so I can see inside and turn the motor with the crank until cyl #1 is at TDC of compression stroke (watch rockers for hint). Then I drop the distributor in place such that the rotor is pointing at the terminal for #1 wire on the distributor cap. (Note firing order is 1-2-4-3). Then try to start. If it kicks back, loosen the timing collar at the distributor and retard the spark (turn dist. clockwise). If it labors to run, advance it (turn dist. counterclockwise).

As previously said, you should get the "Repair Manual" for 1928. There is a wealth of information in there.

Good Luck!
-R

Darla, Rusty Fender is right on with the repair manual, it also says you can use a long screwdriver or a rod inserted into the sparkplug hole to tell when the # 1 cylinder, the front one is TDC and you also have to be sure the valves on # 1 cylinder are closed before inserting the distributor with the rotor pointing to 31 spark plug. The piston is at TDC two times during the 4 cycles, you must be sure it is on the compression stroke, ( both exhaust and intake valves will be closed) and not on the exhaust stroke ( the exhaust valve will be open)
You said the engine was torn down did he remove the cam shaft ? the valves must be in time with the crankshaft the two gears on the front of the engine ,Camshaft and Crankshaft, timing gears must be assembled correctly, there is a punch mark on each gear, the two dots must be together for the valves to be in time. each shaft has a key way that keeps the gears from becomeing out of time, sometimes a worn gear or bearing will allow the cam shaft gear to slip a notch or two, one notch off may allow the engine to start but it will not have full power and will cause missing at all speeds.

Exercise extreme caution in the assembly of the timing and crank gear. DON'T rely on the punched marks, but count the teeth for safety. Many gears are mismarked.

In addition to all that has been said, make sure the #1 piston is on the compression stroke, the piston should be top dead center when the rocker arms are both loose on #1 but the timing mark on the flywheel and the pointer have to line up as well or you are off one full cycle! this could account for back firing throught the carb. Also do not try to start a back firing vehicle with the air cleaner off, this is hazardous. We just lost one Montana citizen and had two more seriously burned when attemting to start an old car with the air cleaner off.It is also possible that a valve is sticking open.

Contrary to what the repair manual says, I would recommend against inserting any kind of instrument into the spark plug hole to find TDC. The piston may hit it and bind, scratching up your cylinder wall or damaging the piston. As for the timing mark, some gears are marked 180 degrees off which will still allow the engine to run but wont jive with the service manual. Some other gears are just wrong. There is a bulletin in the 1928 Chevrolet Service news that tells how to properly mark the gears.

"The crank gear is marked exactly opposite the keyway and will fall between two teeth."

The camshaft gear is marked by locating the tooth exactly opposite the keyway. "Calling this tooth number one, count anti-clockwise, or to the left, 15 teeth and punch mark the fifteenth tooth."

Regards,
-R

EVERY THING SAID IS CORRECT! BUT TO ADD TO MR RUSTYFENDERS COMMENT! NUMBER 1 AND NUMBER 4 PISTON WILL BE T.D.C WITH VALVES CLOSED ON # ONE PISTON, AND THAT WOULD PUT YOUR CRANK SHAFT KEY POINTING STRAIT DOWN . THAT WAS THE EASY WAY FOR ME. WITH MY 28.

N J, and R F Thanks, I always learn more than I give out here!

Thanks Gentlemen for your great help!! Dad who is a young 74 years old, spend last night reading your words of wisedom and playing with the distributor, finally getting it to run!! It's still ruff and needs fine tunning yet....but's running!
Yes, both Dad and I are card carriers to the VCCA and have both joined the local club. But we have only owned this car since Oct and it seems to work different then our Model A Ford.
Dad needed to know which way to turn the distributor and now he knows!! Keep up the great advice.
Again, Thanks for all your help. I'm sure I'll be back on another topic, we start the brakes next week and hope to run the car around without the body to work out all the bugs soon.

Yes, Darla youall are going to see quite some difference in the Chevy and the Model "A". I had a Model "A" as my second car when I was 14 back in 1951, My first was a 1934 Chevrolet 1/2 ton that was "stripped down" from the windshield back, it was a Hot water six and very fast for a 13 year old. I hope to be the owner of a '28 Chevy soon, I have been looking for the "right one" for a couple of years now. I think that your Chevy and the Model "A' are both major players in the history of man's quest for the perfect mode of land transportation.

I just purchased another NORS pre-28 timing gear and as I was placing it up on the shelf I compaired it with the NOS metal Chevrolet gear that I keep just for this purpose. You guessed it, the timing mark is wrong on this gear also. I say again, look at the pictures and COUNT TEETH.

Recently I learned it's great to drive any vintage car(Ford or Chevy) and watch the heads turn. But driving up to a Nursing Home by far has given me the chance to share my new hobby with the men and women who had to drive them 60+ years ago. The stories I have heard and the sparkle in the eyes that I have seen will last with me forever! It's been worth the time we have spent getting these cars a going. We will spend a lot more time on this Chevy (Mostly locating parts), but already I see the faces lighting up as I talk to the Greatest Generation about what's in my garage. I wouldn't trade it for nothing!
It might be awhile before the car is all put together, but THANKS to you fine gentlemen, our engine is running and doing much better with every turn of the screwdriver.
We start the brakes next week! Wish us luck.....

Darla,
See you are in Cincinnati. What good luck, you have many knowledgeable 20s Chevy owners in your area (VCCA Miami Valley Region). Some have been messin' with chev 4s for over 30 years. Even the VCCA Pres lives in the neighborhood.

Yes, we are members of VCCA Miami Valley Club since the beginning of this year. We are learning from some of the club members about how to date this car, since it contains parts from 25, 26, 27 and 28. There is a picnic with the club this Sunday and we hope to ask more questions since we have the engine running on how to best fine tune it. And yes, the VCCA Pres has even given us some good advice on our problems. We only wish that there was more books on this car like there is on the Model A's. But with this Chat room, it sure helps work out some of the bugs.
We now hope to wear our Bow Tie this Summer in our 26 Touring Car (Without Top Bows). By the way, you know where one can get top bows or do you need to make Model T's bow work?