Timing & Distributors

[Buggy Man]

If I replace the distributor on the engine do I have to reset the timing?
Matt

[deltaracer_1]

If you replace the dist. "YES" you need to reset the base timing!

[AdnanRana]

whats the standard for idle speed and advance timing on the M151A2 ?

[raymond]

whats the standard for idle speed and advance timing on the M151A2 ?

550-600 RPM. When setting the timing, line the pointer up exactly with the notch or line on the pulley when timing the engine. If using a timing light with advance, set it to 0, as the timing marks take into account the proper advance. If you do not have a 24 volt light, you can use a 12 volt one by hooking it up to the grounded battery. If you do not have the timing adapter, you can still use a standard induction light by using 1 of 2 methods. You can remove the number 1 spark plug wire (the one that goes to the spark plug at the front of the engine) and replace it with an old one with enough of the metal insulation removed that you can attach the pickup. This is the method I use. Or, you can cut the ends off an old solid core standard spark plug wire and insert one end in the distributor socket for the number 1 spark plug lead and the other end in the number 1 spark plug. When finished timing, put the standard military spark plug wire back on.

Raymond

[deltaracer_1]

FYI---- Setting the pointer to the mark on the crank pully is at -- 6 deg. BTC on my 151. I am planning to chang my dist. from electronic back to the point's style,... just because it was what was on it from the factory.

[raymond]

If you are missing the timing pointer, you may have to time it using a vacuum gauge.

http://www.centuryperformance.com/tunin ... g-148.html" onclick="window.open(this.href);return false;

http://www.secondchancegarage.com/public/186.cfm" onclick="window.open(this.href);return false;

Raymond

[Rickf]

If you put a vacuum gauge on a 151 while you are timing it with a light you might be surprised at what you find. The best vacuum will give you timing that is too far advanced. If you do not have a pointer then you have to determine exact top dead center and make a pointer and then you would set you advance light at 6 degrees. Or you could get a timing tape for that diameter of wheel and install that for your adjustment with a non advance light. I can tell you how to find exact TDC but it is kind of involved and I don't have the time right this minute.

Rick

[muttguru]

Here's an easy-to-follow method of timing your engine and locating where the timing mark should be:-, presuming that you have checked the points/plugs/valve clearances first.
Check the ignition timing as follows (STATIC TIMING):-
1. Take out ALL the spark plugs.
2. Remove the valve cover (rocker? cover),
3. Remove the distributor cap.
4. Stand at the front of the vehicle looking into the engine compartment.,
5. Put your hands on the fan-blade and turn the fan CLOCKWISE (as you are looking at it).
6. While doing this, watch the TWO valves on number 1 cylinder (the one nearest to you).
7. They will go "down" in turn, but there will be a phase when both valves are "up" (closed).
8. As soon as they both look closed, turn the fan ANTI-CLOCKWISE 1/4-turn.
9. Get a thin welding rod (or wire) and insert it into the No 1 spark-plug hole (nearest to you)... you should be able to "feel" the top of the piston.
10. Get someone to turn the fan-blades again SLOWLY, CLOCKWISE.
11. "Feel" the welding rod rise up as the piston comes up to the top of the cylinder (both valves closed).
12. When it stops "rising", that is Top-Dead-Centre.
13. Check the pulley again....look at the edge of the pulley where the pulley-edge has passed the timing pointer (about 1/4 inch beyond the pulley). (This is 6 degrees before-tdc which is the correct engine timing) .Usually, there is a slight "notch" on the edge of the pulley, as if someone had drawn a hacksaw blade across. if it isn't there, or if someone has tack-welded a blob of metal in its place... you can still do it.You should almost certainly find some trace of the timing notch now. If still no sign, approximate 6 degrees and mark the pulley accordingly.
14. When you are happy that you have a good idea of where the notch is or should be, align the notch on the pulley with the pointer by turning the fan-blades through 180 (or 360) degrees CLOCKWISE. Make CERTAIN that the No.1 piston is at the top of the cylinder and that the pair of valves on that cylinder are still CLOSED. Turning the engine 180 or 360 degrees clockwise avoids any errors due to backlash between the timing gears.
Now just have a quick look at the distributor rotor arm. It should be pointing towards cylinder no.1, and when the distributor cap is replaced, the tip of the rotor arm should be immediately under the spark-plug no.1 lead.
If the rotor is facing ANY OTHER segment, let me know, as this will be evidence that the distributor is "out" of correct alignment or possibly the intermediate shaft needs to be turned 180 degrees.
Ken.

[TFischer]

Great information thank you

[Hell On Wheels]

here is a good video for adjusting valves.
https://youtu.be/8y5r3ZSjdx0

[Rickf]

In that video did you notice the exhaust valve rotators were on the intake valves? And one of them appeared to have a missing keeper.