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1946 lincoln v12 lack of power


Obxwrangler
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Need some guidance on my 1946 lincoln v12. Car runs and drives but lacks power for sure. I want to start working through it to find the lack of power issue. Looking for recommendations where to start. It does start and drive, but really weak power and won't pull a large hill in my neighborhood, as well the max speed I get is about 40mph. Transmission,  clutch, and overdrive all work ok. Please advise on list and order of where to start. Thanks in advance.. I have attached picture or the car.

20200425_142624.jpg

Edited by Obxwrangler
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I had a chance to check spark tonight. Strong blue spark on all 12 wires at about 3/8 to 1/2 inch away. Spark would get more orange the closer I got wire end back towards spark plug to hook up like a 16th of an inch away or closer when it would go orange. So I think spark is good. Not saying timing is good, just that spark is good. I took reading at barrel connectors on coil when car running:

Coil black wire has .7vdc  to battery ground car running

Coil red wire 2vdc to battery ground with car running

 

That is what I know so far. Again car runs drives and idles. Just has low power on take off and steep road hills wont make it without losing lots of power and max speed about 40 to 45 mph.

Edited by Obxwrangler (see edit history)
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The V-12 in that car was known since new to be under powered. In the early 50’s they had a Cadillac engine kit to repower them. My neighbor who bought one new did his in 1954. That said, it should easily cruise at 60 all day long. You only have three choices for a problem. Compression, ignition, or fuel. Most people today don’t have a grasp for identifying the issue by feel. One can guess the compression is fine……..or you can spend a little time and actually check it to eliminate it. So since your hunting for the issue……a proper diagnosis is in order. Do the compression check. Check fuel pressure and volume while running……NOT static. Timing can be difficult on the Lincoln’s. A five gas exhaust analyzer would be helpful. You haven’t described in detail how the car acts when it tops out at 40. That’s where I would be interested to see the fuel pressure while moving down the road. It’s very common for inexperienced people to install incorrect fittings in the system restricting flow causing volume issues. It should be an easy problem to fix with correct diagnostic tools and some time. An experienced mechanic should be able to figure it out (read fuel or ignition) in less than half an hour. Problem is today, there are very few experienced people.

 

PS- looks like a very nice car. Is the issue new, or has it been this way since the restoration was finished. Also, it’s likely that you may have both fuel and ignition issues……..

Edited by edinmass (see edit history)
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Went out tonight and made sure all plug wires going from cylinder to correct terminal on distributer side plates,all good.

Per Tom's advice hooked up a vacuum gauge where brass line comes out top of manifold behind carb and plugs into a rubber hose about 10 inches away and that hose heads down to vacuum canister in pass fender well. At that spot I read a steady 15 inches of vacuum with the car at idle. When I gave it gas it went lower towards zero. Not sure what I should have at that connection I T'd vacuum gauge. 

I am thinking next step is to do a good cylinder compression test. 

Edited by Obxwrangler (see edit history)
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Performed cylinder compression check today. Carb held wide open and choke open, results are:

Cyl 1.   108

Cyl 2.  106

Cyl 3.  98

Cyl 4.  104

Cyl 5.  103

Cyl 6. 110

Cyl 7. 110

Cyl 8.  110

Cyl 9. 105

Cyl 10. 95

Cyl 11.  106

Cyl 12.  101

Feel pretty good with these compression results.

Time to head on to the fuel delivery system. I suspect trouble there for sure, as when I recieved car it had a fuel filter then a 6 volt 5-8 psi electric pump then a mr gasket 0 to 5 psi fuel regulator set at 3 psi. This was all under drivers door framework. This was all tied in by cutting copper fuel line and using rubber fuel hose to connect it all and then tie it into the existing copper fuel tube...  Then it came up through copper tube to the flex hose and into glass bowl and mechanical fuel pump and then through copper tube to the carb. Lots to redo in this setup I believe. I think this could be the main issues on low power, starving for fuel.

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  • 2 weeks later...

With the vacuum gauge hooked up, increase the engine speed slowly. If the vacuum drops, you have a plugged exhaust system. If you opened the throttle quickly, the engine vacuum will drop and then come back up when the engine reaches the rpm set by the throttle position.

 

You can do a quick check for fuel starvation by pulling out the choke slowly. If the power increases, you have a fuel delivery problem.

 

The correct fuel line is copper coated steel. It should have a compression sleeve at the tank and at the flex line. I compress the sleeves and then remove the line and solder the sleeve to the tubing. This gives a nice leak free connection.

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  • 3 months later...

Did this ever get sorted out? Those Mr Gasket regulators were a "must have" fashion item 20 years ago. They fail. Imported species. Also, the electric pump should allow fuel to pull thru when it's not running. They too go bad and don't allow fuel to pass whether on or off (just sorted one this summer). 

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