Cadillac & LaSalle Club Discussion Forum

Cadillac & LaSalle Club Forums => Technical / Authenticity => Topic started by: ToddHaugen on January 02, 2024, 07:18:23 PM

Title: engine firing then kicking back, what now
Post by: ToddHaugen on January 02, 2024, 07:18:23 PM
OK folks, I got through the first run suggestions on my original threadFisrt Run Steps (https://www.bing.com/ck/a?!&&p=d6de9491435254e2JmltdHM9MTcwNDE1MzYwMCZpZ3VpZD0yZWZhNjg5OC0xMmExLTZlY2UtMzA3NS03YmMyMTMxMjZmMjgmaW5zaWQ9NTIwMA&ptn=3&ver=2&hsh=3&fclid=2efa6898-12a1-6ece-3075-7bc213126f28&u=a1aHR0cHM6Ly9mb3J1bXMuY2FkaWxsYWNsYXNhbGxlY2x1Yi5vcmcvaW5kZXgucGhwP3RvcGljPTE3MjYzNy4w&ntb=1) I it turns out the I just had to clean up the marks and the 0, 5, and 10 were seen after the funny after marks.  SO I now have spark to all plugs and it catches for 1-6 cylinders and then it seems to kick the engine back.  I pulled the plugs and watched the spark timing is at the end of the compression stroke.  The plugs are properly gaped.  I have not set the dwell, I simply took new points, Aligned to a lobe and gaped at .016 as that seemed reasonable looking at other years but it says to start and then rotate until misfiring and then rotate 180 degrees back to set dwell. I have tried to advance the timing but I cannot get it to start.  Once the engine kicks back the starter disengages and just spins.  I believe this is as expected.  I literally see the belts stop and go counter clockwise just a little when this happens.  Any idea what next steps?
Title: Re: engine firing then kicking back, what now
Post by: Dave Shepherd on January 02, 2024, 08:26:17 PM
Usually this occurs when the timing is too far advanced.
Title: Re: engine firing then kicking back, what now
Post by: ToddHaugen on January 02, 2024, 08:31:30 PM
I have the timing light on it and it seems pretty close but it keeps firing so its hard to get a good timing light reading as it stops rotating when it fires so...  Like how far are you thinking it is going to be advanced?  as in how far will I be rotating the distributor housing?  Since the balancer rotates twice every time the distributor rotates once it seems like pretty small movements but I have not had luck making this adjustment by hand.  Should I be rotating something like 5 degrees between attempts to start?  I have the housing snug but lose enough I can rotate.
Title: Re: engine firing then kicking back, what now
Post by: 35-709 on January 02, 2024, 09:24:15 PM
Double check that your plug wires are hooked up correctly, just two of them crossed may well cause your problem.  As you note, the balancer rotates twice for one turn of the distributor, are you/were you certain that #1 is on the compression stroke and not the exhaust stroke when you installed the plug wires.  Very common for the distributor to be 180 degrees out due to not verifying that #1 is firing on the compression stroke.
Important to sort this out before something breaks like the starter housing or ring gear tooth. 
Title: Re: engine firing then kicking back, what now
Post by: ToddHaugen on January 02, 2024, 10:47:48 PM
I used the thumb over #1 to find the compression stroke and then hand turned the engine so that it was 5 degrees BTDC.  My problem is when I get the timing close enough the engine keeps firing which stops the rotation so I cannot verify with my timing light that the 5 degree mark is at the pointer.  So I have repeatedly refound TDC and then ensured the rotator was pointed at #1.  I did double check the spark plug wire connection to the cap and they are correct.  So I have to assume I am merely firing too early so I need to understand how to get that correct.  When I had it lined up TDC I placed the distributor so that the rotator was pointed at #1 and it seemed like it was firing way too early using the timing light.
Title: Re: engine firing then kicking back, what now
Post by: Dave Shepherd on January 03, 2024, 08:20:27 AM
Possible the balancer has slipped on the hub, try and verify that tdc on # one matches near zero on the balancer. You try just retarding the dist to see if it improves anything.
Title: Re: engine firing then kicking back, what now
Post by: Chopper1942 on January 03, 2024, 10:36:46 AM
Remove #1 spark plug. Rotate the engine by hand until you can feel the piston pushing out air. Install a long thin screwdriver or plastic rod into the cylinder. Rotate the engine by hand until the screwdriver is push out the most and starts to just starts to recede. Rotate back until the screwdriver is at its high point. Now check the marks on the balancer and it should be on TDC/0°. If not, the balancer has slipped.

A point gap of 0.016" will usually give to a dwell reading of 28°-32°. Make sure the rubbing block of the points is on the high point of the dist lobe. Also, put a very small amount of point lube on the point rubbing block.

Again, double check that the plug wires are install correctly. If they are correct and the balancer is on 0°, the engine may have jumped time and you need a new timing chain and gears.
Title: Re: engine firing then kicking back, what now
Post by: TJ Hopland on January 03, 2024, 10:53:02 AM
Have you done a compression test?  I'm just wondering if they all have enough compression that they should run.         
Title: Re: engine firing then kicking back, what now
Post by: Michael Petti on January 03, 2024, 12:39:34 PM
This is a long shot, but sometimes the bendix on the starter gets weak and disengages the starter just as the engine begins to fire. The starter disengages and just spins. The engine does not start due to inadequate cranking time. The cure was a new bendix. It's just a thought.
Title: Re: engine firing then kicking back, what now
Post by: ToddHaugen on January 03, 2024, 12:42:32 PM
I just got the engine back from a complete rebuild.  Unfortunately my mechanic partner passed and so I am not sure the exact state of any one thing.  He was very good so I would be shocked if the compression was off or the timing gear jumped.  We already verified the pulley had not slipped using the suggested approach.  In fact I have relocated and verified TDC multiple times to check my work.  I guess what would be most helpful is explaining how I rotate the distributor housing to find the right timing.  I think I should be looking for 2.5 degrees before the #1 point which is a pretty small deviation from exactly pointing at the #1 point.  So do I just try, rotate a very small amount and try again?
Title: Re: engine firing then kicking back, what now
Post by: dn010 on January 03, 2024, 12:53:31 PM
You can rotate the distributor a bit in either direction and then try to see if it will spring to life. In this case, try setting it back a little to see if it was too far advanced.

Assuming you're working on a 331/365/390, remember that cylinder #1 is the right front cylinder (driver's side) when looking at the engine from the front of the car, not the front left (passenger side) so make sure you're using the correct cylinder.
Title: Re: engine firing then kicking back, what now
Post by: badpoints on January 03, 2024, 02:48:18 PM
Usually when you start an engine for the first time, you leave the distributor loose enough to move it around, while cranking, for the car to start.
Title: Re: engine firing then kicking back, what now
Post by: Jon S on January 03, 2024, 06:57:35 PM
Triple check the firing order and your wires. Sounds like misplaced connections to spark plugs.
Title: Re: engine firing then kicking back, what now
Post by: 35-709 on January 03, 2024, 08:06:03 PM
Agree.
Title: Re: engine firing then kicking back, what now
Post by: ToddHaugen on January 03, 2024, 09:25:26 PM
OK, so the cables are in order but...  Here is the picture from the manual (old car manual project is where you find it) and what I see is it looks like the rotor is expected to point directly forward at TDC and the #1 cable should be towards the back of the back of the vehicle.  That would mean that at TDC it would be pointed at #6, could that possibly make sense?  https://1drv.ms/i/s!AvSAZXJ00YtntoJ6Ly8WqYu79jiIvg?e=6xzn5k
(https://1drv.ms/i/s!AvSAZXJ00YtntoJ6Ly8WqYu79jiIvg?e=6xzn5k)
Title: Re: engine firing then kicking back, what now
Post by: Daryl Chesterman on January 04, 2024, 01:02:15 AM
"Here is the picture from the manual (old car manual project is where you find it) and what I see is it looks like the rotor is expected to point directly forward at TDC and the #1 cable should be towards the back of the back of the vehicle.  That would mean that at TDC it would be pointed at #6, could that possibly make sense?"

No, this does not make sense!

I am attaching a picture of the top of a Cadillac 390 engine and it shows how the distributor sits in the engine.
From this picture you can trace the #1 wire on the left-front (driver's) side of the engine back to where it is located in the distributor.  With the engine at top-dead-center on the compression stroke, the distributor rotor should be aligned with the #1 tower of the distributor cap, which is on the left side of the distributor cap (as shown in your picture from the manual).  Left and right are always determined as a person sits in the driver's seat.  You may have to lift the distributor and reorient the rotor shaft and housing to get this positioning.  Once it is in this position, you can follow the instructions on the page you posted to get the timing close enough for the engine to start.  The position of the distributor in the picture makes it convenient to access the points-adjusting window.

Daryl Chesterman
Title: Re: engine firing then kicking back, what now
Post by: dn010 on January 04, 2024, 09:47:17 AM
Just to muddy the water a bit, technically if the crank is at TDC compression and the rotor was pointed to "6", all one would need to do is install the #1 wire at "6" and continue installing the rest by the firing order and the engine would run.

However, the way I view that image in the manual is that "front" is just referencing where the front of the engine is in relation to how the distributor is installed (so you install it with the window easily accessible as noted above and the oil pipe & vac advance out of other obstacles on the engine) and there is nothing telling us on the distributor imagine "this is where the rotor needs to point". On the other images, that is where it is telling us where on the cap #1 should be for uniformity across all engines, which is where the rotor should be pointing when you install the distributor at TDC on compression.

It may help greatly if you post photos of what you're dealing with on your engine...
Title: Re: engine firing then kicking back, what now
Post by: PHIL WHYTE CLC 14192 on January 04, 2024, 01:48:42 PM
It is possible to fit the distributor 180 degrees out and still get the engine to run (very rough). Don't ask me how I know this! Btw my car is 1954 CDV.
Title: Re: engine firing then kicking back, what now
Post by: ToddHaugen on January 06, 2024, 12:19:51 AM
OK folks, thank you for all of the help!  We are very close!  I got the fuel pump rotated so number one basically pointed at the drivers seat which seems to be what everyone is saying.  At first I was 180 out but figured that out quick but not until I had a bib pop out the drivers side exhaust.  Fixed that and got the oil pump rotated so that #1 was pointed at the drivers seat at TDC.  Used starter fluid and cranked.  Got  good fire then back fire so I retarded the distributor housing and it ran better and better until...  I had the fan off so that I would not accidentally hurt myself and I had the pulley too loose and on the last fire the, see link, the belts came off.  Reassembled everything and at first the belts were too tight and the engine cranked over slowly and did not spark.  Loosened the belts and reattached the fan now turns over at the right pace.  I have spark to every plug and the timing light flashes right at 5 degrees BTDC but now the engine will not fire at all but as you can hear in the video it was almost there.  What could be keeping it from firing now?  https://clipchamp.com/watch/zDXcgs7aM59
Title: Re: engine firing then kicking back, what now
Post by: Daryl Chesterman on January 06, 2024, 01:25:19 AM
From what I am seeing in the video, you are not getting fuel in the carburetor.  It is firing when you spray into the carb, but there is no gasoline in the carb to sustain the engine running.  With the choke butterfly propped open, you should be able to look down into the venturi of the carburetor.  While giving the carb linkage a full stroke (engine off), you should see two strong streams of fuel spray down into the front venturi of the carb.  If there is no gasoline spraying, that means the float bowl has no fuel in it.  Disconnect the fuel line from the carburetor and place a hose on the end of it that is long enough to reach a container and crank the engine to see if the fuel pump is pumping gas.  Be extremely safety conscious and have a fire extinguisher close by.  It would be best if you have a helper to make sure that any gas that may get pumped is directed into a container.  If there is no gas being pumped, then you will need to check out the fuel pump.

Daryl Chesterman
Title: Re: engine firing then kicking back, what now
Post by: ToddHaugen on January 06, 2024, 01:41:30 PM
Sorry Daryl, I realized my message was not super clear.  The video was right before The water pump pulley popped off.  I took the fan off but did not realize the fan screws also hold the pulley to the water pump spindle.  So after a could of good almost fires it fell off and all of the belts too.  So I put them all back together and now, no changes, the car does not fire at all.  I verified spark to all cylinders.  The only difference I can identify is the engine turns over slower now that the starter is also turning the water pump.  So if it has compression, starter fluid, and spark but wont fire is there anything to do other than go back to step one and verify TDC and points alignment?
Title: Re: engine firing then kicking back, what now
Post by: dn010 on January 12, 2024, 12:44:32 PM
I agree that you're probably not getting the fuel you need to the carburetor. You shouldn't have to use starter fluid, you should be able to pump the accelerator pedal a few times to get the fuel you need. With the engine off, I would second the recommendation of opening the choke by hand and looking down the carb throat as you pull on the throttle linkage to see if you're getting jets of fuel. From there, you may have a poorly adjusted choke preventing the engine from running.