Model A power

The plug on the eight looks like oil is passing through that cylinder

When the engine for my car was first rebuilt it wouldn't go over 52 after break in, at 3000 miles the Babbitt failed , I took it apart, the cam was worn, the valve seats wide and sunk down.
New valve seats and a good used B cam that I had changed the car, 67 mph, from 16 mpg to 23 mpg
 
Finally. I got the chance to run a compression test and m/l confirmed what I feared. Using my trusty Snap-On tester, here's test #1 results:
#1 45 psi
#2 50 psi
#3 55 psi
#4 55 psi
These were with the engine hot (180-200 degrees at the outer surface of the cylinder walls) and the throttle wide open. I then squirted ATF (per someone's recommendation) in the cylinders and retested. For test #2 I got:
#1 60 psi
#2 60 psi
#3 62 psi
#4 63 psi
My assumption is the rings are worn in cylinders 1 & 2 along with some corrosion I saw in the bore scope. The valves seem to be sealing well. Cylinders 3 & 4 built pressure quickly (4 strokes) were 1 & 2 took 7 or more strokes to reach peak pressure. Several hours later I installed the plugs and ran the engine to burn out the ATF hoping for a miracle. I retested (test #3) and got the same results as test 1. No miracle. Has anyone tried "Engine Restore"? I've heard it can work minor miracles. I'm not usually one to try additives to fix something like this but its worth a shot.
Other things I noticed/confirmed:
I get a 30+ degree drop from the top radiator tank to the bottom measured near the necks. Top was 173 and the bottom was 137. Cylinder wall skin temps were within 10 degrees front to back.
When warm, the engine will idle ~450 rpm (advance at about 25% from full retard)with the GAV fully closed. At 1000 rpm (advance about 50%) and up the GAV needs to be open 1/4 turn with no load.
It doesn't appear to be a tuning issue as all cylinders read pretty low and there's 10 psi difference lowest to highest (~20% difference).
With no load she'll run all day long at 1500 rpm and never go over 180 degrees at the upper radiator tank. As long as I keep her on flat ground (not too easy here), watch the temperature, and don't push the speed I can still drive her until funds are available for a full rebuild. Now to decide stock or touring?, inserts or babbit? updraft or downdraft carb?
 
Within 3 lbs sound ok to me until rebuild can be done. If the compression is the only reason for the rebuild you can run it for years like that.
 
I've always used within 10% max to min on compression, which would be about 6 psi. I am almost double that. The underlying reason for the rebuild will be loss of power and being able to maintain a safe speed. I suspect it has been run for years in its current state, but I'd bet it hasn't been driven more than a few hundred miles since 1991. I hope to change that. I'll be picking up a bottle of engine restore and driving it daily to see if that helps. I've got nothing to loose at this point.
 
Kevin in NJ said:
A Model A from the factory would run 60+ mph. This on the crappy roads of the day.

Properly restored to original you should expect to be comfortable running at 55 MPH and hitting 65 MPH (depending on body style) should not be an issue. Running 55 MPH is not an issue with a stock drive line and you should expect to get upwards 50,000 miles on the engine.

Properly restored is defined as restoring the engine back to factory tolerances with respect to balancing and precision of fit. For a bit more power going to a B cam is a simple change, my opinion is a new cam from Stipe is the most bang for the buck. The cam is the heart of the engine and many are not in very good shape so you are usually in need of something better for your car, so going to a B type grind is a smart use of your money.

Of course this does not help with your problems, but at least lets you know what you should expect. I recommend reading "The Legendary Model A Ford" to get a better perspective to how the cars were driven back in the day and what you should expect from your car today.
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This is strictly my opinion but, suggesting to most of us Model A lovers that we should expect to merrily cruise down the road at 55, and even accelerate to 65 at will, is a bit mis-leading. Without getting into what constitutes a properly rebuilt engine, suspension system, or brakes, I believe the vast majority of us have cars that will run all day long at 35 to 45 mph - but at speeds over 45 mph they get a bit squirrelly! I'm not one to lay awake nights worrying about how to make my Model A go faster. I'm confident that it will still be chugging along long after I'm gone and, in the interim, it's nice to enjoy the slower pace and the simple sounds of a happy Model A.
 
I was at a car show in Longmont (Colorado) one summer day, when I came upon a Model A that looked like it hadn't had much restoration on it.

The owner had brought his family to the show and had coolers attached to the sides and back with rope. He told me that the Model A was in original condition and hadn't had any major work done. He got it from his father and just liked to drive it around.

I asked him what speed he drove it at, and he said around 55 mph on the interstate (I25) as if it was no big deal.

I'm convinced that if a Model A is brought back to the condition it was in when made, that it would go 55 mph without any trouble.

Marc
 
you need to run it more before you make a decision . as said above , timing is important for both power & heating . your compression is not that bad , but as said wet cylinders show ring wear . maybe run a lil marvel mystery oil in the gas . I would give it more time to seat things after sitting ......... good luck
 
marc hildebrant said:
I was at a car show in Longmont (Colorado) one summer day, when I came upon a Model A that looked like it hadn't had much restoration on it.

The owner had brought his family to the show and had coolers attached to the sides and back with rope. He told me that the Model A was in original condition and hadn't had any major work done. He got it from his father and just liked to drive it around.

I asked him what speed he drove it at, and he said around 55 mph on the interstate (I25) as if it was no big deal.

I'm convinced that if a Model A is brought back to the condition it was in when made, that it would go 55 mph without any trouble.

Marc
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---but do you really feel safe at 55 mph in a car with 1930s suspension, brakes, and handling characteristics, not to mention the lack of crash protection? IMHO no Model A is suitable for cruising the Interstate Highway System unless it's on a trailer - and I've already said my piece about speed in general. Let the flaming begin.
 
Most of our "tours" are done at 50-55 mph. Did about 160 miles round trip this past Saturday.
 
CarlG said:
Most of our "tours" are done at 50-55 mph. Did about 160 miles round trip this past Saturday.
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I'll make one more comment and then I promise to keep quiet. The difference in the duraton of your trip would only be 39 minutes at 45 mph. For me, that's just 39 more minutes to enjoy the Model A.
 
Mcorell, that is sufficient compression to enjoy your A for many more years driving around at comfortable cruising speeds. I drive my cars anywhere between 35-55 and as Tom said, I also feel most comfortable and stable between 35-45. Im not sure why you are limited to lower speeds but if you continue to spend some time (in between drives) tinkering, you will eventually find the issues. Verify proper fuel flow from tank, clean and properly adjust carb, check, double check and triple check timing and make sure you have good spark from the points and at the plugs. Depending on how long your car sat between runs, you may want to remove the exhaust pipe and see if that makes any improvement (as we all know mice love to make nests in mufflers). Good luck!
 
Thanks for all of the information. On flat ground the car will run faster than the steering is capable of running comfortably. When it comes to hills, and we have them here in the Smoky Mountains, it runs out of power fast. I've done all of the suggested tuning along with all new ignition components and a cleaned carb and fuel system. When I got the car the GAV wouldn't turn and was stuck about 1 turn out. The timing is spot on. It was very much like setting up my old Maico dirt bikes with point ignitions. Right now the budget will not allow any major repairs (too many doctor bills) but they are planned. I simply need more power to pull the hills in my area while maintaining a 35-40 MPH speed. I also need to rebuild the 7 tooth steering box. It will be a fun process....
 
Those spots on the cylinder walls "may" be from some surface rust & "may" polish over, with more driving. At least it DOESN'T appear to have sharp scoring lines in the cylinders. These old engines are QUITE "FORGIVING"!
DO try a 160 thermostat, better flow control, "may" help performance & any heating issues.
Bill W.
 
I took the old gal for a long drive (20 miles) today but never got more than a few miles form home. The difference was remarkable. I put "engine restorer" in her about a week ago and have been running her about 30 minutes a day at about 1000-1200 rpm. Due to stormy weather I didn't drive her until today.

She was able to pull short 2-3% grades and accelerate from ~25-40 mph over a 1/2 mile stretch. I also hit 47 mph on a long level stretch of road. No overheating was noticed. Only once did the motometer show any red and then it was only 1/4" or so. I'm not ready to say it was the "engine restorer" I put in her yet. It may have been my set it and forget it approach to the GAV and spark lever. I set the spark lever all the way down (full advance) once she was warm and set the GAV to about 1/2 turn out. She may had been a tad rich on the level sections.

I'll say its been 20 years since she was driven 20 miles in one outing. Heck, that may have been all the miles put on her between the time my grandfather passed and when I got her last year.
 
Chief said that many times, a Model A's top speed was limited by SOFT valve springs that allowed the valves to "float" @ higher RPM's, like, it ran good up to a certain speed, then, just went to a smooth, "BLAAAAAAH" stage.
Chief always put NEW valve springs & even spacers, to increase the tension a little more!
Bill W.
 
Quick update: the car is still running great. I've hit 50 mph and ran out of road while still accelerating. I'd say it makes good power up to about 2300 rpm where it starts to run out of air (valve float?). Still the turnaround has been impressive since I poured the "engine restorer" in about 80 miles ago. last time out it was mid to upper 80s and I could pull a 2% grade about one mile long and actually accelerate up the grade w/o overheating or boiling. Once I get another 80 miles or so on her I will repeat the compression test to see if there are measurable results, other than seat of the pants.
 
mcorrell said:
Quick update: the car is still running great. I've hit 50 mph and ran out of road while still accelerating. I'd say it makes good power up to about 2300 rpm where it starts to run out of air (valve float?). Still the turnaround has been impressive since I poured the "engine restorer" in about 80 miles ago. last time out it was mid to upper 80s and I could pull a 2% grade about one mile long and actually accelerate up the grade w/o overheating or boiling. Once I get another 80 miles or so on her I will repeat the compression test to see if there are measurable results, other than seat of the pants.
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You mentioned "engine restorer". It may have been noted in one of the posts above but I could not find out what it is. What do you mean by this term? What brand?? or ??
 
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