Optima battery suddenly too weak to crank on 48 DeSoto!

[Sniper]

When I got my 51 it had about 50 psi in each hole, it runs fine.  I ought to retest, I might just do that tomorrow, depending on how rough the dentist gets with my teeth, lol.

[DonaldSmith]

I recently learned that we should turn over the engine several times for compression testing each cylinder.  Pump it up till the needle stops.  I've gotten more uniform results that way 

[MarcDeSoto]

I just did another compression test with oil.  Here are the results:  

 

1 - 100;  2 - 110;  3 - 100;  4 - 110;  5 - 110;  6 - 110

 

I think maybe I should recheck my tappet clearances to make sure they are correct.  

[allbizz49]

I think it's time to put some juice to it and fire it up. Also, I always do my valves running, hot. Once you fire it up and get it to temperature, check them while running. I always set them a bit loose, just a bit. 

[Sam Buchanan]

Just now, allbizz49 said:

I think it's time to put some juice to it and fire it up. Also, I always do my valves running, hot. Once you fire it up and get it to temperature, check them while running. I always set them a bit loose, just a bit. 

 

Yep...stop messing around with it and start 'er up.  ?

[MarcDeSoto]

Well, I got my new water pump from MoparPro, so I can have cooling too.  Yes, I'm very close to trying to start it again.  First I'm going to make a test light with a 6 volt bulb and static time it.  Then, I'll fill the float chamber with gas.  Then crank it.  

[Dodgeb4ya]

Just fire it up...too much posting

[keithb7]

To recap, @MarcDeSoto has tried to fire it up. It would not fire. We are working through the steps to eliminate variables that would prevent it from firing. 
 

Your compression numbers indicate your valves are decent. The added oil has helped seal up the rings. This is expected. I think your compression and valves can probably be eliminated from further troubleshooting. 
 

We have set out a plan to simply address fuel delivery. So check that off the list of variables. 
 

All that is left is spark at the right time. 

To recap and confirm:

Distributor is indexed to the oil pump so #1 is at approx 7 o’clock? The #1 spark plug wire when seated in the distributor cap sits right over the rotor in the 7 o’clock position?  Firing order 1,5,3,6,2,4. Plugs are clean? Wires are not able to ground out? There are 2 distributor timing adjustments. A minor and a major adjustment . Major is under the distributor, not easily seen. Minor adjustment is the small bolt easily seen. It bolts and locks the distributor to the block. 
 

There is a chance your major adjuster is out of adjustment too far. Then you can’t dial in the timing using the minor adjustment. I’ll post a few pics of major and minor adjustments. 

Edited January 4, 2023 by keithb7

[keithb7]

 

[allbizz49]

I'd bet that when he first tried to start it, it was flooded, badly.... He continued to crank it which killed his battery. Now, knowing what he knows, it won't get flooded and it will light off for him. Everything being right, it should start pretty quickly. 

[RobertKB]

Lots of discussion on being at TDC on #1 to run the plug wire correctly to the distributor. Gotta make absolutely certain this is on the compression stroke, not the exhaust otherwise you are out 180 degrees on the distributor. Each cylinder only fires every second revolution. It’s an easy mistake to make. Been there, done that many years ago. 
 

Also, depending on how the oil pump and distributor are indexed after a rebuild #1 plug wire may or may not be at 7 o’clock. I have one engine where #1 spark plug wire is at 10 o’clock. The engine could care less as long as it’s timed right. 

Edited January 4, 2023 by RobertKB

[LeRoy]

Its nice to see so many folks thinking through this and offering assistance, the car community is still a great place to be (despite the rest of the world going to hell in a hand basket). It's a good edumacation moment too, everyone that's thinking it through is learning whether we like it or not

[LeRoy]

9 hours ago, keithb7 said:

 

that distributor is way too clean

[MarcDeSoto]

I made a test light with a 12 volt bulb that does light up and go off when I spin the crank.  The manual says to put the timing pulley on TDC and then loosen the distributor to do a minor adjustment.  I turned the dist. both ways and the light would not go off.  Then I cranked the engine to see when no. 1 fired by looking at the visible spark plug attachment.  I didn't have the other spark plugs installed, but I don't think that makes a difference when you are just trying to static time it.  I noticed that the plug was firing at about 25 degs. before TDC!  Would this indicate that I need to do a major distr. adjustment?  My manual does not go into detail on that procedure, so maybe someone can tell me.  It's because of things like this that Keith's instructions to make sure all of the fundaments are right before you start cranking like mad just to get it started, that I believe in Keith's philosophy here.  

Edited January 5, 2023 by MarcDeSoto

[DonaldSmith]

Maybe the oil pump needs to be adjusted.  I'm starting a new post, "Oil Pump Indexing."   I tried scanning the page from the Shop Manual, but it didn't come out so well.   Give me a few minutes to transcribe it.   

[Kilgore47]

Turn the engine to TDC on the #1 cylinder on the compression stroke.  Remove the distributor cap and note where the rotor is pointing.  Move the #1 spark plug wire to that location and then re install all the other spark plug wires in the normal firing order around the cap.  This will get the timing close to the correct spot.  Close enough to start and then it can be fine tuned once you get it started.  The engine will run fine like this.  The engine doesn't care where the wires are located on the distributor - it only cares that it gets spark at the correct time.  Or you could re index the oil pump.  The oil pump may have been installed in a different rotational position than recommended.  

 

[MarcDeSoto]

When I installed the oil pump, I didn't know that it was supposed to be indexed.  The shop manual says nothing about it.  Could the dist. need a major adjustment?  I will check your post out about how to index the oil pump.  

[keithb7]

I wish I was there to help @MarcDeSoto  I am confident we’d settle this is about 2 mins. 
 

So many people offing so many tips here it gets confusing.

 

I 100% agree you must have #1 piston at TDC firing stroke. Cap off the distributor. Where is rotor pointing? That will be where your #1 spark plug wire goes. Carry on around the rotor hooking up wires 5,3,6,2,4. In that order.  Static time it again. Still too far out of TDC? You are likely out 1 tooth fwd or back on the distributor drive gear.  Trial and error time. Remove dizzy again. Turn dizzy so it moves  1 gear notch on the camshaft gear. Forward or back. Static time it again. Better or worse? Gotta get that static light to come on very close to piston TDC. Worse turn dizzy gear the other direction. Static time it again.  You said it was firing 25 deg before TDC. Indeed my friend you are way out. 
 

Always #1 piston at TDC, compression stroke whenever you static time it. You will be very good at this when you are done. 
 

Edited January 5, 2023 by keithb7

[MarcDeSoto]

I thought I had to remove the oil pump to turn it one gear tooth?  No?  When should a major adjustment be done on the dist.?  I did a major adjustment on the bottom of the dist. and now the spark is about right.  

Edited January 5, 2023 by MarcDeSoto

[keithb7]

Sorry yes. Side out the dizzy. Slide out oil pump.  Move oil pump gear 1 tooth on camshaft drive gear. Reinstall oil pump and dizzy. Static time. Rinse and repeat until you get it right. 

 

I forgot about that little notch in the dizzy shaft. Oil pump is driven off cam gear. Dizzy driven by notch in oil pump. 

Edited January 5, 2023 by keithb7

[DJ194950]

Can we start one of those Go Fund Me deals to get you a airplane ticket to Temecula for a (short) visit?

 

If the forum member all kick in a few$$ we can get it done!  ?

 

 

[MarcDeSoto]

Yes, I think I can get Keith a flight on Southwest Airlines!  when is it correct to do a major adjustment on the dist.?  

[allbizz49]

It doesn't matter which way the oil pump is indexed. Just get number one cylinder at tdc on compression. Pull the cap and see where the rotor is pointing. Should be pointing at the number one post on the cap. 

[Sniper]

Actually, it does matter, otherwise the vacuum can might run into things before you get the timing you want.

[allbizz49]

Yeah, I'm talking if he's off just one tooth on the pump.