1951 Cambridge. Might need an engine rebuild

[matt167]

I bought what was supposed to be a nice old car but after getting it delivered ( part of the price agreement ) it's becoming evident that it was a quick flip and has been driven enough to load a trailer.  When I went to see it, it was running rough cold but cleared up and started to run nice.   When it was delivered, it was down a cylinder and the previous owner commented it was cold ( it was a cold day ). Knowing the flathead 6 is somewhat known for sticking valves I wasn't that worried. The price I paid included the probability of some tinkering and still come out okay. I had to have him deliver it to my moms as my house was another 1.5 hours farther for him. So it's currently stuffed in my moms garage.  I brought a U haul to come recover it last weekend and I could not get it to run.  I thru new plugs and wires on it ( plugs fouled and ancient, wires crumbling and original ).  I opened the distributor cap and the connections were loose and falling apart.  I still have switching voltage at the coil so it should have life. I did not have the right wrench for the now damaged screw ( previous owner likely used pliers ). I stuck it together is all I could do there .   I didn't run a compression test as I didn't want to waste the battery and the charger I have is a 4A automatic charger that kind of works ( Harbor freight special ).    I'm not 100% positive the distributor internals are right.  Can someone show me a picture of an IAT distributor assembled?  My '52 motors manual shows the specs but does not have a picture. 

 

What should my check list be to get it running?   The guy for sure put a new coil on it which I suspect could be bad. And he had for sure been in the distributor, but the coil is switching so the points should at least get it running.  Is there a possibility he has the wrong cap on it?  Would a different cap physically fit? 

 

I say engine rebuild as, depending on the compression it may come to that

 

  

Edited March 10 by matt167

[plymouthcranbrook]

It certainly is possible to have the wrong cap and rotor. Ignition parts need to be ordered by distributor number to help insure they are correct. And I am sure you already know the failure rate out of the box for new parts is high. 

[matt167]

I know the parts situation and the quality of current production points.  I didn't get the number from the distributor but I'm fairly positive it's the IAT distributor that it should have.  

Edited March 11 by matt167

[Ivan_B]

So, the car is not running very well, is that it? I would not panic just yet. First, get it into a warm garage and do a regular "tune-up". Check the spark quality, check the points, adjust timing, dwell, idle speed (use a vacuum gauge). Make sure that the carb is clean, not flooding, and you have no vacuum leaks. And, yes, do a proper compression check (no plugs, throttle all the way open) just to see what you are dealing with 🙂

[bacelaw]

This forum has taught me not to panic until you have all the vital signs.  A compression test is absolutely worthwhile.   Even if you had a valve issue, it could be fixed without pulling the engine.   Move methodically from compression test to the other tests mentioned - you may find something simple. 

[matt167]

Well, it's not currently running. I could not get any life out of it this past weekend while I was there except pops and cracks here and there. But the spark checker I bought would not light up ( enclosed flashy one, not what I call a gap zapper ). I'm figuring I probably have multiple issues

 

The real question is if the distributor being amiss cause it to miss on a single cylinder... The day I got the car I actually took it down the road and back and it did start to break up a little but remained running 'okay ish'... It at least let me know that the brakes stop the car straight although they growl a little, and the speedometer, and temp gauges work correctly.  The same day  I started it to move it 5-6 times as I actually had to remove a built in bench to fit it in my moms garage. The last time I tried to start it that day, it coughed but would not catch. I assumed it was flooded and simply pushed the car forward and shut the door.

Edited March 11 by matt167

[Sniper]

3 hours ago, matt167 said:

The guy for sure put a new coil on it which I suspect could be bad.

12 volt coil?

 

3 hours ago, matt167 said:

Can someone show me a picture of an IAT distributor assembled?

Best I can do, my 51's distributor

[matt167]

My guess is the coil may be 12v or it's hooked up backwards. I cannot guarantee anything other than I know for a fact it did run  The coil wire also only sort of kind of fit. The boot was too small for the coil.

 

That distributor looks correct. The blue sleeve goes over a copper wire. The only thing I see different is, the condensor uses a standard wire with fork connector, so now I wonder exactly what is going on.  I forgot to bring a flash light/ work light with me  and relied on a flood light in a heat lamp housing that my mom happen to have. Worked but was a little inconvenient so I didn't get a good look ( nor a good picture ) of anything. The screw the wires attach to was left loose and falling apart

[9 foot box]

   This is a IAP-4103A-1 distributor that was in 49 and 50 Plymouths. The bare wire is a ground. The other wires need to be insulated. Here’s another, with a different condenser. This ground wire needs to be insulated.

[Ivan_B]

Did you get yourself a repair manual, already?  

[matt167]

1 hour ago, Ivan_B said:

Did you get yourself a repair manual, already?  

I've had a '53 motors manual for a very long time.

[matt167]

I've got no compression on the center cylinders, #2 is weak at about 40 PSI and the rest test even at 60 PSI.  I ran out of time to do a wet test, but I may fill all the cylinders with PB blaster ( I bought a gallon ). See if it's stuck rings or valves.  I may have to pull the head off, so I may buy a head off the site and have it milled in preparation

 

Oh and the cause of no spark is the wire running from the isolator to the points was broken, among all the connections being loose..  I made a wire but it does not fit right and seems to be shorted. Contemplating the pertronix kit as it bypasses the isolator issue. Not sold as I know recent pertronix quality is iffy.  I found a cheap IAT-4003 and ordered it for parts. Hopefully I can fix the isolator issue and perhaps it has a usable wire

Edited March 18 by matt167

[Sniper]

1 hour ago, matt167 said:

the rest test even at 60 PSI.

 

Ordinarily they will tell you 60 psi is bad.  But my 51 Cambridge has been like that for the 4 years i have owned and driven it, 

[keithb7]

Fingers crossed low compression is just a result of leaking valve seats. Lap those up, new gaskets, ultrasonic the carb. Deal with the distributor. She might go well!…Here’s hoping. 

[Los_Control]

These flathead engines imho have weak valve springs.

If you get a little bit of sludgy oil built up around the valve stems, the lifters will push the valves open, the springs are not strong enough to pull the valves closed again.

 

So the head of the valve will be swinging in the breeze and not coming back down to seat.

Soaking the cylinders with a light oil like marvel mystery oil can loosen the sludgy oil enough the valves will start operating again ....

If you can get enough compression to get the engine to start on 4 cylinders .... A good chance the heat and running oil will have all the valve stems clean and operating.

 

That would be my goal, soak the cylinders ... keep spinning the engine over ... try to start it when it has 60 psi on a few cylinders and just let it idle and warm up.

If you are lucky, you will hear the other cylinders start to kick in as the valves start moving again.

The more it runs, the better it will run.

 

Or you may end up pulling the head in the end ... no compression on a few cylinders is not uncommon ... when the engine was parked, those valves were open, the oil turns to glue and they no longer slide ... springs are too weak to pull them back down ... heat and clean oil can fix this.

[Ivan_B]

15 hours ago, matt167 said:

pertronix kit

I would recommend attempting to fix the OEM stuff, first. It works well when properly setup  

As for the compression - too bad. You might get away with just quickly removing the head and re-lapping the valves, if the rest of it is in good shape.

[matt167]

I ordered the IAT distributor so hopefully I can get one working.. I found an NOS set of Airtex/ Wells points and condenser in the trunk. I had pertronix in a 1951 Chevy and it was great, but that was 15 years ago or so. Ive heard the stories of failure recently. But hopefully I'll be able to get a distributor working.

[Los_Control]

I may be the biggest guesser on this forum .... I guess it might be this, or I guess it might be that ... until you actually test a few things, you will never know.

 

For example, A weak squirt from the accelerator pump will not stop the engine from running ... it will give it a hesitation when you step on the gas ... but it will still run.

 

You need to know if you have spark or not at the plugs .... if not, you need to backtrack the system to see where you lose it.

 

$$ well spent having a extra distributor around and setup to run points ....

So far we still do not know if you have spark to the plugs or not .... makes no difference to buy another distributor if you do have spark.

 

I would change the thread to asking for help for basic troubleshooting procedures, rather then buying random parts.

[matt167]

Oh I verified no spark at the plugs with an spark checker on #1. I stuck it on a snow blower which I knew runs to verify the spark checker is working. I found the broken wire which goes from the isolator to the points under the cap, and with the condition the previous owner left the points in, and trying to build a new wire with wire and terminals I had on hand which aren't the compact type terminals needed. I think the ignition is shorted.  I'm hoping I can put the isolator back togther correctly with a correct and repaired wire, along with new points that are not twisted and a condenser it should be good to go.. It ran before and I know at least 3 cylinders are marginally healthy so it will run again.

[Los_Control]

OK I wish you luck with everything .... I too am a fan of electronic ignition and have it installed myself.

I used a slant 6 distributor and converted my original distributor using parts from the 49 Dodge and from the newer slant 6 .... then I used a GM HEI to complete it.

Just saying that I have OEM Dodge contacts in the distributor .... OEM GM reading the signal and sending it to where it needs to be.

Either part can be bought at a local auto parts store.

 

Your petronix may work as well, just need to get working parts and make it work .... probably cheaper/easier then replacing the distributor.

[matt167]

I'm hoping to get the wire and isolator parts from a distributor that hasn't been messed with to get it up and running. Or pull/ swap distributors. whichever is easier.

 

The pertronix may be the way I go in the long run, as Napa can get the modules as a replacement part over the counter at a cheaper price vs the entire kit, but the points should work in the short term. The only hang up is the IAT distributor requires a slight modification that will make points no longer fit.  The only real issue with points is the quality of the parts in recent years.