J-15 Won't Fire

[m610]

Hi. Frustrated. Never had this problem before.

 

I just finished rebuilding a J-15 that was in a Nissan forklift. I know, not exactly Ratsun, but I figured someone here might be able to help.

 

The motor cranks, compression is good, but it does not fire. Timing? My timing light does not flash. I put the pickup on the coil-to-distributor wire and it flashes when I crank, so the coil and Petronix are working. But when I put the timing light on any of the spark plug wires the timing light does not flash.

 

I got a new rotor and cap, the usual suspects, from a local ag equipment shop, and still I have this problem.

 

I did try a range of timing settings to see if I could get my timing light to flash.

 

I picture the rotor pointing to the space between the cap's contacts when the coil fires being the only possible reason for this. I checked the magnet on the distributor shaft to make sure it had not shifted. It hadn't.

 

Is it possible to put this distributor in backwards somehow? The housing as to go in a certain way because of the tab used to set and fix the timing, but maybe I have the rotor pointing the wrong way? Which was is the rotor supposed to be pointing when the crank is TDC and ready to fire for #1? I have it pointing to the front of the engine (back of the forklift).

 

I've never encountered this problem with a motor, although this is my first J-15.

 

Thanks in advance.

Mike

[datzenmike]

Pull the coil wire off the distributor cap and hold near ground and turn the engine with the starter... confirm that it should spark. If it does, do the same with any plug wire (stick old plug in end and hold on ground) to confirm that yes, there is no spark. No spark? then the rotor and or distributor is incorrectly timed.

 

Set the engine to TDC compression stroke on #1 cylinder (both intake and exhaust valves should be closed, find the mark on the crankshaft pulley and set it on the timing pointer) and take the distributor cap off. The red? pick-up coil on the Pertronix should be on a cam lobe and the rotor should be under one of the wires on the cap, or should be within adjustment range by twisting the distributor.

 

Sorry I have never worked on a J series but this should get to close.

 

 

 

 

[m610]

I spent the afternoon on the engine, starting by doing as suggested: rotate to TDC for #1, check direction the rotor was pointing.

 

It was way off, somewhere between #4 and #2.

 

I figured the shaft driving the distributor was off a tooth. Took care of that and cranked. No go. Repeated the TDC test and the rotor was way off again. ?

 

After a few more tries I discovered the rotor was too long for the new distributor cap, but it fit the old cap.

 

With the old cap and rotor back in it still did not fire. Started over from scratch and I had the shaft for the rotor wrong.

 

Fixed it, verified at TDC the rotor was pointing at #1 and the magnets for the Petronix were in the right position, +/-.

 

No change. My timing light fires when the pickup in on the coil-cap wire, but not any of the spark plug wires.

 

Here are some photos from my Facebook page. (Sorry, I don't have a convenient https site to store them on.) All photos taken at TDC for #1 and show the position of the rotor and shaft.

 

Mike

 

https://scontent-sjc3-1.xx.fbcdn.net/v/t39.30808-6/313047222_10230488285778779_121347093480356016_n.jpg?_nc_cat=107&ccb=1-7&_nc_sid=0debeb&_nc_ohc=QA6Yp3LaqRcAX8DHPz7&_nc_ht=scontent-sjc3-1.xx&oh=00_AfAHkkbh4KawCQuhkW3GcAb6szPT_vksj-FJEuFuxLwgCA&oe=6361690C

 

https://scontent-sjc3-1.xx.fbcdn.net/v/t39.30808-6/312965693_10230488285378769_292501098052525881_n.jpg?_nc_cat=100&ccb=1-7&_nc_sid=0debeb&_nc_ohc=Bkefx4--F8YAX_xYS6d&tn=h2o7Y9Nb3eVYu9Jj&_nc_ht=scontent-sjc3-1.xx&oh=00_AfBzhV0qhV9ccIIGqRqwrGNegXV-Fjvt59-D_1BwhVvl0g&oe=63607A72

 

https://scontent-sjc3-1.xx.fbcdn.net/v/t39.30808-6/312318155_10230488286098787_1883212071184177963_n.jpg?_nc_cat=108&ccb=1-7&_nc_sid=0debeb&_nc_ohc=5iK3kBSPOJMAX9b-yex&_nc_ht=scontent-sjc3-1.xx&oh=00_AfCZXU1SsJiZAZlZ_7SPtGVnBhrmfvjGY1YwM7hdk5TrjA&oe=63619FBC

 

https://scontent-sjc3-1.xx.fbcdn.net/v/t39.30808-6/311932194_10230488286498797_4394692541324853955_n.jpg?_nc_cat=100&ccb=1-7&_nc_sid=0debeb&_nc_ohc=hlYQfcGUsdIAX_vNBsI&tn=h2o7Y9Nb3eVYu9Jj&_nc_ht=scontent-sjc3-1.xx&oh=00_AfBI_EsuHj8g5ruG51-GbgossyjR_TCbbCxSQNu9E12SeQ&oe=6361C955

 

[datzenmike]

 

I'm unfamiliar with the Pertronix and where the  pickup coil fires in relation to the center that rotates. Obviously the coil fires????

 

Is that center black/green thing adjustable? 

[m610]

That black/green thing has four small magnets in it that trigger the coil. It slides right over the lobes on the shaft. It is not adjustable.

[banzai510(hainz)]

Im not familiar with the pertronix in a J motor dist but if its lined up ok it should work.

Pertronix says use with the ballast resisitor or the 3 ohm coil you can buy and not use the ballast.

 

OK you get a spark on the center coil wire. Most people just put the end near the chassis and you can see it spark when you crank the motor.

 

now you put it to TDC rotor pointing at number compression stroke. the what ever way it goes. I assume counter clock wise and go 1 3 4 2 fire order.

I will have to assume the dist spinal is in correct!!!!!!!!!!!!!!

 

you say you dont get a get the timing light to go off. To me the spark is going down the wrong wire or not at all staying inside the cap.

 

Make sure yougot the fire order correct and you know which pistons are 1 2 3 4 also.

 

you could just unloose that dist bolt and turn the dist till it seems like its going to fire. adv or retard.

 

Im not a fan of a timing light to trouble shoot the fire order the way your doing. I would put to TDC #1  thn take the number one plug wire out of the spark plug and place near ground. if it fires close to the Zero degree mark on the distributor plat then I say the dist is lined up correct and put the correct wires on the rest with the correct fire order.

[datzenmike]

I timed my VW by setting crank at 5? degrees (or w/e the old dubs used to be) on the timing mark. Take number one wire off and hold near ground. Quickly twist distributor back and forth making smaller and smaller arcs till you knew just where the points were when they opened. Good enough.

[m610]

I'll need a timing light eventually to set the timing correctly, but I am using it now just to see if I get any spark at all.

 

Firing order is indeed 1342, and the rotor spins CCW. But even if I got this wrong I'd expect to get a spark, just not at the right cylinder.

 

The engine is in pointing to the rear, forklifts are FWD/RW steering, so cylinder #1 is towards the back of the vehicle.

 

Somehow spark is not making it's way through the distributor cap, either due to the rotor being between electrodes when the coil fires, or some other reason, and I've done all I can to make sure the former is correct, and considering what typical advance curves are, you can be quiet a bit off from perfect timing and still get a spark. The photos show the rotor pointing at #1 when the crank is at TDC for #1, and I checked and the magnets that trigger the Petronix are in position as well.

 

Again, weird thing here is I did not do anything to the distributor during this repair other than remove it during disassembly and reinstall it during assembly, after a little cleaning. My mistake could be elsewhere, but I verified the position of the shaft driving the distributor is correct, so what else is there?

 

Mike

 

P.S. Where do you guys get your parts for these motors? I have been able to find some locally (Sacramento, CA), but some came from New Zealand.

[m610]

Success! And a little humility. Never too old to learn.

 

I went in for another afternoon of guessing what could be wrong and stumbled on the finding that at TDC and the ignition on, sweeping the distributor through its timing adjustment range got the timing light to flash. Finally I could see that spark was getting to the plugs. Of course this begged the question why it didn't get the timing light to flash when cranking. Well, screw the timing light, let's pull a spark plug and see if it sparks. It did. Well then, let's turn on the gas (LNG) and see what happens. It puffed, then fired. After a few more tries while adjusting the timing and idle speed the motor ran, and sounded really nice.

 

I figure what was happening was while cranking the current through the plug wires was not enough to trigger the timing light. Once the engine was running the timing light worked great.

 

Lesson learned. Sorry for the bother and thanks for the help. Hope this come in handy in a future scenario like this one.

 

Mike

[datzenmike]

On 10/27/2022 at 5:21 PM, datzenmike said:

Pull the coil wire off the distributor cap and hold near ground and turn the engine with the starter... confirm that it should spark. If it does, do the same with any plug wire (stick old plug in end and hold on ground) to confirm that yes, there is no spark. No spark? then the rotor and or distributor is incorrectly timed.

 

LOL, well it was one of the first things I suggested. It happens.

 

We only got the J13 in the '66-'69 520 trucks. Best suggestion is from a parts company that supplies to forklift trucks. Mexico and Central America used the J15