Hello all! I was given a 1958 Ford F100 for my 50th birthday this past summer - Yes, I know, very blessed! The truck has 161k miles on it and has recently started smoking in a bad way. It's a white/gray smoke coming from the oil fill on top of the engine, from a metal hose under the engine and also from the exhaust. My initial thought was head gasket but my coolant level has not changed and it's not burning through oil. I had a friend suggest that it may be blow by. I am a tinkerer but not a seasoned mechanic. I am also very much into DIY so I am all ears and not afraid to get dirty. Any thoughts, suggestions or help is much appreciated Ken
You need to take compression readings at each spark plug. You will need a tool for that if you don't own one and either a remote starter switch or a friend to crank over the engine.
A compression gauge and a vacuum gage can tell you A LOT about the mechanical health of the engine. It is where I usually start when troubleshooting and then go forward from there using the information / results from the compression test and the vacuum readings.
I never had a burnt valve that would cause blow-by. Blow-by is usually a bad seal internal into the engine. A burnt valve usually causes an engine miss as compression is going out the exhaust. Seldom ever burn intake valves. As stated above. Intelligent use of a compression gauge will get you to the heart of the problem. It is more than just getting compression readings.
I have to go with OldOlds there. You can go to Autozone and "borrow" a compression gauge. Meaning you pay a full deposit and take it home and use it and then take it back when you are done and get the deposit back. A great way to have access to tools you don't use often enough to want to buy them. There is a correct and proper way to do a compression test. 1. remove all of the spark plugs. 2. pull the coil wire out so you don't have fire jumping out of the plug wires. 3. Prop the throttle wide open. choke should be wide open too. 4. screw the gauge into the first plug hole in line and crank the engine over so you see/hear it hit 5 times. That means the piston came up on the compression stroke 5 times. Write the reading down and repeat though the rest of the cylinders one at a time. You are looking for two things. First you are looking for decent compression that comes reasonably close to the pressure specified in the tune up chart. Second you are looking for even compression between all of the cylinders. You shouldn't have much over 10 lbs difference high to low. That is how I was taught how to do a compression test 55 years ago as a high sophomore in Auto Shop and have done it ever since and taught my students for the 13 years I taught high school auto shop.
You also should listen to things while you are cranking the engine. If there is no reading on the gauge you may be able to hear where the compression is going. Into the next cylinder? Rad cap off, see bubbles? Likely bad head gasket. Oil fill cap off? Hear air in the block? Hole on a piston, broken rings. At least these are places to start looking. Thanks for rest of the instructions, Mr48chev.
A leak down tester would be more useful and that can possibly be borrowed also. Two gauges with air pressure from a compressor, one gauge measures air going into the cylinder, the other the amount staying in the cylinder. You can also hear the leak easily. On an aircraft engine we generally use 80 lbs. of air in and hope to see at least 75 on all cylinders. On a car engine you could use 100 and the other would then read a direct percentage. Piston has to be at TDC on a compression/firing stroke.
To me, the giveaway is the excess smoke coming out of the crankcase vent cap and the road draft tube. Coupled with the smoke out the exhaust and the high mileage, I'd do a replacement or overhaul. Check the compression as suggested. If it's low, pump a little motor oil into the sparkplug hole and recheck the compression. If it comes up, it's the piston rings. Still, with 160+ miles, I wouldn't bother with a repair.
Was referring to an Intake valve but didn't specify. Happened on an old 302, #4 intake if I remember correctly.
I was always taught that when doing a compression test, the engine should be moderately warm versus stone cold as the readings may differ significantly! Right or wrong?
This is clearly an old Ford telling you it wants a V8.......via smoke signals!! Sent from my Pixel using The H.A.M.B. mobile app
As has been stated Easiest first hook up a vacuum gauge and see what it’s doing at idle and revved up to a constant rpm. Do a google search and it will go into detail about what you see/ should be seeing. Do a dry and wet compression test as has been detailed above ( when wet with a few squirts of oil in the cylinders and compression comes up, issue is in your bottom end ) Then do a leak down test and this will confirm any and all findings ( less then 10-15% difference between cylinders and all cylinders should be even) and remove rad cap, oil cap and air filter . Listen for air excaping if you hear it from carb it’s intake valve issues , tail pipe exhaust valves , oil cap rings, rad head gasket Good luck sounds like it needs a rebuild or freshen up at least. But doing these steps will avoid a shop trying to bamboozle you into work that may not be required .
It's just wore out. Overhaul it, or rebuild it, or replace it.... Then again, you said "it's not burning through oil". How many miles have you driven it lately, without having to add a quart of oil?
Squirrels right, it obviously has a problem and doing all the test will only lead to the same conclusion, replace or rebuild. Besides that nice looking truck deserves a fresh engine.
Find a 262 its a bolt in. Or go with a 300 six. Its worn out and not worth what it would cost to rebuild it.
It's worth asking what weight oil you're using in it.... I had a 223-powered Ford years ago that the PO was using 10W40 in it, it blew/used oil and had been rebuilt. Switched to straight 30W as recommended in the owners manual and my oil consumption stopped.
Considering how much you have tied up in the truck I would have the engine rebuilt. You have ability to remove and install engine.
161 thousand miles,to make the old truck reliable I would suggest a rebuild if you want to keep it original. HRP
its likely the engine will need bored and the crank turned and valves and seats.By the time you buy the parts and pay for machine work ect you can buy a good used engine. If it was mine I would likely install a FE or a 262 or a 300 six. Ive got all three in my hoard.
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