Looking for ideas on an Engine purchase & pickup

[dorelse]

Cool Jim - Thanks for all the diagnostic work!

[Rich_V174SS]

If compressions are consistent and low it could be something as simple as needing a valve/head reconditioning, maybe a honing and new rings.

[dorelse]

Dang Ford...  HA!!!   

I mean, I pay $500 for an engine with no guarantees it'll run...and then...it doesn't run!   

[Jason]

Well, you could drop it off at my buddies Sampson Racing Engines in Inver Grove Heights and have him take a look at it since it's up here.

Jim, have you used that compression tester on other engines? it's not new is it? I have seen some new cheapies run low like that.....

[Tonka Jim]

Jim, have you used that compression tester on other engines? it's not new is it? I have seen some new cheapies run low like that.....

It's an old one & always fairly accurate. It read 140 psi on my 140 & Joe's read 135 psi.

[dorelse]

I may bring it up there eventually Jason...right now, I'll get it home, build a stand for it to sit up on and it'll likely stay that way until next winter.   The Metric just needs a carb cleaning, tach fixed and the seat fixed and she'll be ready for summer.

[Plugcheck]

  This may not apply to OB's, but low compression readings are not uncommon for used engines that have been sitting awhile.  Performing a wet compression test and a leak down would help narrow down the rings or valve train issues.  As Aaron from "Fast and Loud"  would say, engines, they just wanna run.  Given fuel, spark, and some compression, it should at least fire.   When cranking does it develop oil pressure?  Does the distributor turn when cranking?  Is there some relation to the rotor and #1 cylinder?  Love to help, but I'm here and its there.

[dorelse]

Made it home about 3pm.  Drove through snow the entire way.

Good to see everyone at breakfast!!!

[dorelse]

After going over all the wiring, and cleaning up some questionable work, its looking a little better now.  Its clear that there's no power to the coil when the motor isn't 'starting', using the purple/yellow wire at 12V.  All the schematics show a resistance wire (purple) dropping voltage down to the coil (+) when running, that purple wire (and a light purple wires) stop at the choke on this motor.

Seems like the alternator conversion was only about 95% completed...getting the starter rebuilt so I can at least get the motor turning over at 'full power'.  I want to get the no spark issue resolved.

[Rich_V174SS]

That resistance wire starts at the choke Dor, and goes into the wire loom along the valve cover and should exit near the ignition coil. The purple/yellow wire that is on the coil should be coming from the slave solenoid under the exhaust manifold and is your bypass power to the coil for cranking. The alternator should be the "single wire" type with a self generating field and would have a large red or orange wire from the terminal on the back going to the main battery lug of the starter, or at least attached to the main feed wire that originally went to the voltage regulator which was hopefully disconnected from the system.

[dorelse]

Pictures are missing from above post Doran ...
Just two circles with  - signs in them ?

Naturally, I see them.  They're hosted on Photobucket, but not playing well it seems.  I'll fix it.

[dorelse]

That resistance wire starts at the choke Dor, and goes into the wire loom along the valve cover and should exit near the ignition coil. The purple/yellow wire that is on the coil should be coming from the slave solenoid under the exhaust manifold and is your bypass power to the coil for cranking. The alternator should be the "single wire" type with a self generating field and would have a large red or orange wire from the terminal on the back going to the main battery lug of the starter, or at least attached to the main feed wire that originally went to the voltage regulator which was hopefully disconnected from the system.

Yes, 1 Red wire off the alternator that I've followed down to the starter area.  Its spliced into 2 wires, a Orange wire & a Red wire that used to be attached to the voltage regulator.

I've been following the instructions in the link to check & confirm everything was wired correctly.  Purple/Yellow wire comes off the 'I' post on the slave solenoid and up to the (+) side of the coil.  That obviously means their's 12V to the coil when the key is in the 'start' position, but without that brownish-purple wire, there's no power when its in the 'run' position.  That wire seems to only go to the choke and is buried in the wiring loom as its not run up to the coil.  I'll keep looking.

http://www.wagnerproducts.com/dc607.htm

[dorelse]

Its interesting in your photos that you have the grey wire on the (+) side of the coil...every diagram I've looked at says that goes to the (-) side for the Tach? 

[Rich_V174SS]

Its interesting in your photos that you have the grey wire on the (+) side of the coil...every diagram I've looked at says that goes to the (-) side for the Tach?

It's not, optical illusion. The grey is on the negative side with the black wire from the distributor. Just the two purples are on the positive side. It's more visible in the top pic with the blue plug wires.

[dorelse]

Its interesting in your photos that you have the grey wire on the (+) side of the coil...every diagram I've looked at says that goes to the (-) side for the Tach?

It's not, optical illusion. The grey is on the negative side with the black wire from the distributor. Just the two purples are on the positive side. It's more visible in the top pic with the blue plug wires.

Ok, great, your pictures are blocked at work, so I was looking at them on my phone.  That's what I have for my (-) side as well, just need to find that resistance wire now.  I know a lot of guys have flat out removed their choke plate completely from the carb.  Any reason I can't just extend that resistance wire over to the coil if I take the choke off completely?  It was something I was planning to do anyway.

[Rich_V174SS]

The resistance wire gets its power from the other purple wire going to the choke. So when you turn on the key power is applied to the choke to start warming it up so it opens as the engine runs. From that connection the coil gets its power through that resistance wire but at a reduced amount so the coil doesn't overheat, the resistor wire takes the place of a ballast on the older systems.  I don't know why you'd want to remove the choke, it's necessary for warm-up and it needs power to open so the engine runs right. If you remove the choke function the engine will be hard to start. Also, the resistance wire is a specific length to provide the correct resistance to the coil. Shortening it reduces the resistance and the coil could get hot.

[dorelse]

The resistance wire gets its power from the other purple wire going to the choke. So when you turn on the key power is applied to the choke to start warming it up so it opens as the engine runs. From that connection the coil gets its power through that resistance wire but at a reduced amount so the coil doesn't overheat, the resistor wire takes the place of a ballast on the older systems.  I don't know why you'd want to remove the choke, it's necessary for warm-up and it needs power to open so the engine runs right. If you remove the choke function the engine will be hard to start. Also, the resistance wire is a specific length to provide the correct resistance to the coil. Shortening it reduces the resistance and the coil could get hot.

Removing the choke has been done by a few guys in the club, and that choke has failed on me before leaving me stranded during the meet a few years ago. 

I do understand that the resistance wire needs to be a specific length, and I'll look again tonight, but I really don't think its in the bundle of wires that goes up to the coil...its simply not there.  Only 3 wires in that entire stretch, Purple/yellow, Grey & Green (I think) for the oil pressure sender.

I suppose I just need to start tracing that wire and seeing where it ultimately goes (or doesn't).  I agree it needs to be there.

[Rich_V174SS]

I suppose I just need to start tracing that wire and seeing where it ultimately goes (or doesn't).  I agree it needs to be there.

Start at the choke and follow it into the loom, it's probably the darker of the two wires. From there it should just take a right turn in the loom and go to the coil.

that choke has failed on me before leaving me stranded during the meet a few years ago. 

Yes, they do go bad. Sometimes the heater inside opens up and the choke remains closed. I've replaced them for people a few times.

[dorelse]

Found the resistance wire cut about 12" back and taped off...Rich has me pointed in the right direction for running a replacement wire.

[dorelse]

Just to foster my own understanding...the key point of the wire, is to drop from 12V to 9V to the (+) of the coil so it doesn't fry when running.  The same could be accomplished by using a 12V keyed (run position) source to a 12V - 9V ballast resistor to the coil using regular wire.  Same difference correct?

Obviously I'm going to do it the right way, and the kit is on its way...but that would account for the ballast resistor we found on the motor Jim.  The PO was trying to drop the current via the ballast resistor since the purple wire had been cut off.