Engine Assessment Questions

AA Ford Discussion Group relating to the repair and restoration of your AA Ford.
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David R.
Posts: 260
Joined: August 17th, 2019, 1:52 pm
Body Type: Chassis
Model Year: 1930
Location: WV

Engine Assessment Questions

Post by David R. »

Need to decide whether or not to pull engine. I have very little history on this truck. I don't think it is original engine, SN has no AA prefix and bell housing, starter, gen etc.,. all painted red, engine block not. Came from an estate where it had been stored in a barn several years. Engine is free and has compression on all cylinders. Haven't attempted to start it. (Rebuilding starter now.)
What wiould you do?
I thought I would pull oil pan and clean and put fresh oil in before I try. Should I (could I) go ahead and check bearing tolerances while the pan is off?
Should I pull head and valve cover too? Can I check cylinder wear from bottom side with pan off? Should I pressure test block for water leaks?
What would you do? Should I go ahead and just change oil and try to start and see how it sounds, runs?
Appreciate input from some more experienced A-AA guys.
I have taken the approach so far to try and only do things once. For example; there was no steering gear in truck when I got it. I found a used one and instead of sticking it in the truck so I could move it, I went ahead and completely rebuilt it, painted it, cleaned and painted frame area where it goes and installed. Now I don't have to do that part again.
KimVanOrder
Posts: 753
Joined: August 11th, 2013, 4:25 pm
Body Type: 82-A Platform
Model Year: 1928
Location: Hamilton, Mich.

Re: Engine Assessment Questions

Post by KimVanOrder »

here is my answer. What do you enjoy doing? Do that. :D
KVO
Dec. '28 AA
David R.
Posts: 260
Joined: August 17th, 2019, 1:52 pm
Body Type: Chassis
Model Year: 1930
Location: WV

Re: Engine Assessment Questions

Post by David R. »

Good answer. I’m having a blast with all of it.
Cschaff63
Posts: 98
Joined: September 14th, 2017, 5:57 pm
Body Type: Dump
Model Year: 1928
Location: Pa

Re: Engine Assessment Questions

Post by Cschaff63 »

I would say it depends on final goal for truck, if you are just going for a driver, get that sucker running and see what ya got!
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1crosscut
Posts: 877
Joined: December 25th, 2010, 7:22 pm
Body Type: 82-A
Model Year: 1929
Location: Lincoln, NE

Re: Engine Assessment Questions

Post by 1crosscut »

Sounds to me like you get a good bit of satisfaction by working on mechanical things.

At the very least you need to pull the pan, clean it, check the oil pump, remove the valve cover and clean out the valve chamber.
While the pan is off you should also check the bearing clearances on the rods and the mains.
You can do this with the engine in the truck but it is one heck of a lot easier to do it with the engine out of the truck. Pulling an engine is not terribly difficult and usually one person can have it out and on an engine stand in less than 4 hours.
With the engine out the first thing I would do is pull the three main bearing caps off for a look. Then I would pull the rod caps off.
If the babbit looks good to this point you can just check and set the clearances using plasti gauge and reassemble. However you will not get a look at the babbit in the block itself. To check that you will need to remove the flywheel, timing gear cover and lift out the crankshaft. This will give you a good look at the babbit and you can make sure that the passages feeding oil to the mains are clear.
Hopefully to this point things are looking good.
With the valve cover off and it cleaned out you can check the valve clearances and set them if it has adjustable valves.
Of course if you do all this you will need to get the full engine gasket set and replace all the gaskets and the rope seals on the crank shaft.

You mentioned that you have compression on all four cylinders. What are the compression readings?
65 lbs is about what you should expect on a fresh engine rebuild with a stock head. It's okay to have lower compression on all four cylinders... to a point. What you don't want is for the compression to be overly uneven. Say 52, 53, 50, 35.

If the lower end looks good and you have good compression then you could probably get away with not pulling the head and go many miles with no troubles. If you opt to leave the head on you should at the very least check the torque of the head bolts.
Pulling a head can go very easy but it can also be a pain in the rear. There is always the possibility of studs twisting off etc...

Just some things to thing over. As for me I usually will go the full route and take an engine completely apart and inspect everything. Doing so will take time and effort but it will cost nothing but your time and effort if you end up finding the engine to be bad.
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Dave
David R.
Posts: 260
Joined: August 17th, 2019, 1:52 pm
Body Type: Chassis
Model Year: 1930
Location: WV

Re: Engine Assessment Questions

Post by David R. »

I really do enjoy working on it. I almost feel guilty sometimes having this much fun by myself. A lot to think about. My end goal is a dependable driver, not a show winner. That said I still want it as original as possible. There is a lot to be done here. One part of me wants to hear it run asap; the other part wants to go Dave’s route and pull engine for complete tear down.
I may go ahead and pull engine. Engine mounts need attention anyway and if it needs machine work there is plenty more to do while it’s out. Front axle needs rebuilt. Rear springs, brakes, basically everything; not to mention building a body.
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