Case 310B distributer swap

[rob vds]

I bought my old backhoe last year after an engine fire and now I want it to start earning it's keep.
The distributer had been hot enough to melt the point's plastic and it sat a few years outside with no cap so it looked pretty sad. I took a similar distributer (prestolite IAD-6004-2F) instead of autolite IAD-6003-2J and installed the drive gear from the case. I set the static timing for spark at TDC and tried to start the engine. It didn't even fire or pop once although the clapper on the muffler showed airflow. By turning the distributer I was able to get the starter to jamb up but no fire.
Is there a reason this distrbuter won't work properly? Where should I set the static timing? Why are there governor weights in a distributer when there is no vacuum advance? I think this distributer came from a wisconsin FWIW
Thanks, Rob

 

[rlp]

You must be getting the engine to fire if you can stop the starter by turning the distributor. I think you may be 180 degrees off on the timing. With number one spark plug off crank the engine till you feel compression on your finger. Now bar the engine over to aproximatly 4 to 8 degrees before top dead center. Now install your distributor and set it to number one.

 

[rob vds]

I have the valve cover off so I can see when #4 valves are rocking

 

[Joe (Wa)]

Prestolite & Autolite are the same company, just an era name change.

The governor weights, opposed by spring tension, advances the spark by centrifugal force relative to engine rpm.

A factory distributor for 300-300B 148 cid engine is IAD6003-2J. The J is the gov springs designation for the correct advance curve. The VAC 124 cid & 400B 148 cid engines, one of the factory distributors is IAD6003-2F. The F is a different spring (tension?) but I use both interchangeably in 300-300B with no noticeable difference in performance.

The 4 in your distributor p/n changes something but I am not familiar with that dist. Why did you have to swap the drive gear? Could the gear configuration change the rotor position relative to TDC on this engine?

The rest of this is for IAD6003-2F or J installed in factory attitude. Dist can be installed in other positions and timed right but I am going with factory Here.

You don't know if your dist is configured right so try to get everything right on for static timing.

Turn the engine CW (viewed from the front) placing #1 piston 4°BTDC on the compression stroke. Rocker arm motion on #4 ok to find the compression stroke on #1 but to find near TDC watch #1 piston in the plug hole. When the piston stops at the top of the stroke look in the timing hole on the bell housing. Turn the crank back until you see the line marked DC, continue another 4° to next line marked IGN. That is the correct crank position for static timing. Continue turning a little further and then come back until the IGN line is lined up with the pointer to take up slop.

Pull the dist cap, rotor terminal should be pointing about 3 o'clock (toward the engine front). If not the dist is configured wrong for this engine OR the dist drive gear was not stabbed in the correct tooth mesh.

CORRECT TOOTH MESH: Pull the dist up just out of gear mesh. Turn the rotor between 4 & 5 o'clock. The gears are helical, as they mesh the rotor will turn ccw back to near 3 o'clock. Tighten the clamp bolt.

STATIC TIMING: Rotor turns CW. Loosen the adjustment screw. Turn the dist head cw till the points are closed. Now turn the head back ccw until the points just start to open. Tighten adjustment screw.

Rotor should now be just starting to pass under the cap tower contact for #1 plug wire. Put the other 3 wires in the towers in firing order 1-3-4-2 in the cw direction.

In a perfect world, timing is now spot on. It will probably be off a little but not enough to affect engine starting.

To get it perfect after starting the engine use a timing light. Warm up and idle the engine at 500 rpm or less. If you are using an induction timing light you can time the engine with the pickup on #1 or #4 wire or the coil wire. Coil wire is the best as the multiple flashes light up the hole making it easier to locate and align the pointer to the flywheel IGN mark. Any variation between #1 and #4 firing is engine/dist wear.

Joe

 

[rob vds]

Wow, that should get me a long way forward, I had no idea there was a timing hole in the bell housing!
Is the dc mark actually TDC and IGN is 4 degrees before TDC?
I find it hard by myself to turn the front hydraulic pump shaft with a pipe wrench through the loader arms while holding a probe in #1 hole so I have trusted the 2 valves rocking #4 as TDC. I simply dropped the dist. in the hole put the rotor on to see where #1 wire would be then installed the cap, energised the coil and turned the dist. till I had a spark on #1 and tightened the dist.
The gear on the wisconsin dist. was a lot bigger than the case 's so I swapped them to match the worm on the cam. It is possible the Wisc had a staggered crank rather than 2 pistons at TDC while other 2 at BDC. I assume however that the 4 sparkplugs fire every 2 revolutions evenly spaced as that engine was rated a few hundred rpms faster because of better balance.I was delighted to stop using wisc. engines about 25 years ago!
Thank you very much, Rob

 

[rob vds]

I found the hole in the bellhousing, it is very inconvieniently located. There is no sign of a pointer, should it be centre of hole? ( I am viewing through a mirror)

 

[Joe (Wa)]

Yes, the cylinders fire 180° crank degrees apart.

Timing marks as in the pic, hard to see in that little hole sometime. I put a dab of white paint between the marks, shows up good on a timing light especially if you use the coil wire.

DC is for dead center, Either #1 is TDC on the compression stroke and #4 is TC on the exhaust stroke or vice versa. IGN is ignition timing 4° BTDC of either #1 or #4 is firing pending which crank rev you're on when the light flashes. That is why you can use #1 or #4 wire or the coil wire. If you use the coil wire, you get 2 flashes ea rev as opposed to 1 with a plug wire, you won't see anything on the flywheel when #2 & #3 fire cause there is no mark to see but you get either #1 or #4 on ea rev. Extra light really helps spot the mark.

I turn my '56 w/FEL same way with a pipe wrench as you do. You don't need a probe to see the piston crown, very visible with some back light and a pen light. You see the crown down a 1/2" or so before TC, by the time you realize it has stopped, you will be pass DC on the flywheel so that is why you use the flywheel marks to get it right on.

I often stab a dist on the fly like you did, even on any part of the rev, but you have an unknown dist so give youself the best change of getting it right or proving the dist incompatible.

From your posts you're no stranger to engines. I don't do all the crap I posted above either, but sometime you just have to bite the bullet and go the kindergarden route just to be sure.

Joe

 

[Joe (Wa)]

Well, I should have reviewed that better before, or reread after posting.

This sentence: "That is why you can use #1 or #4 wire or the coil wire. If you use the coil wire, you get 2 flashes ea rev as opposed to 1 with a plug wire,"

Should read: 2 flashes ea rev as opposed to 1 EVERY OTHER REV with a plug wire,

I am sure you are experienced enough to pick up on and ignore a dumbsh!t miss-statement like that.

Joe

 

[rob vds]

I like the coil wire idea for more light, I have to get it running so I can give it a try! I hadn't noticed your little slip but it is good to correct these things so as not to confuse people who read this thread in the future. I appreciate your help, Rob