Technical Starting an 8RT that's been setting a while.

I need some help? I have an old F1 truck 8RT that has been setting for years that I am trying to revive. I have it on an engine stand. The compression, cold with no carb and all the pulgs pulled is about 95 psi in all cylinders. I am spinning it with a 12V battery and have installed a 12 V coil. I pulled a 94 carb of my running flathead and installed it. No fuel pump hooked to carb. Just filling the carb through the air horn, and squirting down the carb. I am just trying to get it to fire and run for a few seconds. I am getting it to fire while the starter is turning, but then just when it should be taking off, the starter dis-engages and it dies. I am not real familiar with these starters. Is there some reason a starter would dis-engage a little early on it's own. I did grease the starter gear shaft were the starter gear moves forward and backward. I have not changed the points and condenser and the points have some wear but apear to be gapped in a reasonable fashion. What should the gap be when you go to 12V? .014-.016 still? Any help would be appreciated. I am just trying to get it to run until the carb runs out of gas before moving on to the fuel pump and cooling system ect.

 

After you get it to fire (or before) I'd suggest checking the oil pickup for sludge. If its a 8rt it should have the large clean out cover which will make cleaning the pick up screen easier.

 

That is what the round plate is for on the bottom of the oil pan that the plug screws into? I did not know that. Thanks. I changed the oil already but I will definitely do that.

 

I'd change out the condenser with a new one. They can cause all kinds of problems.

 

Sounds reasonable. I do think the ignition is weak. Spark plugs are sparking but not very hot, to my eye. I am using starter cables and have the positive cable clamped to the starter housing. I am wondering if I need another positive ground to the cylinder head. It all seems to be basically working but just wont take off. Been at it for 2 evenings now always thinking the next try it will go.

 

Looks like you are running it with a positive ground. Is your 12V coil wired correctly?

 

I have the positive side of the coil wired to the negative battery post.

 

The 12V coil is from a 60's mustang.

 

Do you have the ignition wired correctly? Sometime these engines are wired with two ignition leads; one that is hooked to the solenoid and bypasses the ballast resisttor so the ignition gets the full 12 volts while cranking, and a second that is hot all of the time and goes thorugh the ballast resistor. If the second circuit is not connected, the engine will fire when turning over but when you release the starter, it cuts the circuit and the engine dies.

It will all depend on how your test stand is wired. I have mine set up so the ballast resistor is controlled by a toggle switch so I can cut it into and out of the circuit at any time.

 

I am running 12V negative right to the coil positive side. I hooked it up this way by looking at my running positive ground 6v car. It has + and - on it's coil and that is the way it is wired. ?

 

You should have the positive side of the battery connected to the positive side of the coil.

 

Even if I am still running positive to ground?

 

If you're just trying to get it to fire on 12 volts why positive ground? If it were me I'd use negative ground and wire it accordingly. IIRC early Mustangs used a ballast resister. When I'm trying to get an engine to run for test purposes I use a 12 volt internal resister coil, a plastic 3 gallon boat gas tank for fuel, a Ford type solenoid, and a solid state electric fuel pump that I keep just for that purpose. JMO

 

That makes good sense. I will do that. Based on Martys comment and a little more reading. I do think I have my coil wired backward. Going all 12V neg ground will simplify things.

 

Pos coil terminal to pos power. Doesn't matter if the pos is used as the ground its still positive.

 

This is what I do also. It eliminates old wiring and fuel problems so its easier to track down any gremlins.

 

Success!

 

Sounds like you have got a winner there Doug.

 

This old flatty seems to run really good. One item I notice is that I can hear one lifter ticking a little more than I like after warm up. I am not going to be happy running it like that. Please share your thoughts about how to fix that with minimum disassembly of the engine. With my limited understanding of how the valve train is solid, I am guessing that if I want to fix this I am going to have to pull at least one head in order to replace that valve with a slightly longer one. I guess my basic question is that I don't see how I can rework the lifters to get the clearance right without pulling the heads. This motor looks like it has not been apart in a very long time and I am kind of nervous about being able to get the head bolts out. I have no budget and am trying to stay out of the machine shop. Please share your thoughts and thanks.

 

Try some Marvel Mystery Oil in the gas or maybe even drizzle down the carb while the flattie is running. Might help. Can't hurt.

 

Are you sure your not hearing the Fuel Pump talking? Use a stethoscope to pin point where it's coming from. If it's a valve with no adjustable lifters one fix would be to grind that Valve taking some off both the face and the seat. That will close up the Gap. Down side is that if it's wide gap you probably have a cam lobe going down.

 

I had a reground cam in mine had to put an adjustable push rod on the fuel pump to stop noise. Be sure not to adjust rod too long will distort fuel pump lever.

 

Thanks for the good ideas. I have to take the heads off to do much of anything to the valve train right? I will try to listen to the fuel pump rod.

 

Because of the way the stock valve system is set up, they can't go out of adjustment unless there's a problem with the engine. Sticking valves are a common problem with flatheads that have not been run for a while, and I think you're actually quite lucky that you don't have a dead cylinder or two. (I picked up a wrecked '50 that had sat for 40 years that had two valves stuck completely open; once I got them freed up it ran fine.) The Marvel Mystery oil solution proposed above is a good idea, but you may not be able to run the engine long enough without a cooling system for it to have any effect. If you could throw a fan belt on it and hook up some sort of cooling system (a garden hose plumbed into the lower water pump inlets might work) so you could run it a while, there's a good chance the noise will go away.

 

To do anything to the Valve train the intake needs to come off, then one or both heads if more than an adjustment "IF" it happens to have adjustable lifters.

 

I have a cooling system on the engine stand. Perhaps I will use the MMO and run it and hope for a sticky valve.

 

FYI, Your video is marked "Private".

 

Sorry

 

I'd take the intake off. It may have adjustable lifters in there. Set the gaps and move on.

 

When First got my truck , had what seemed one valve sticking , added MM,oil to crankcase, gas and a tablespoon full in each cylinder, noise went away in about a mile of driving.