Engine inspection (with pics)

[Licensed to kill]

So, I pulled the head to change the gasket and inspect the cylinders. What I found was zero ridge except for cylinder 3 has just the SLIGHTEST hint of a ridge. Could be carbon. Pistons are .100 over, cylinder walls have NO cross hatching at all. So this is after 300 miles using 5 quarts of oil. Plugs should be a lot more fouled if it was burning that much IMO. The wife was following me the other day and said that it is smoking a bit. I'm thinking perhaps pulling the pistons, deglaze the cylinders, new rings and it should be good. Not convinced that all that oil when through the cylinders so must be leaking more than usual somewhere. Thoughts??.
[IMG][/IMG]



[IMG][/IMG]

[tinkirk]

sounds like a good idea
check and clean the valves while your at it

[burner31]

Lap your valves while you're there, it's cheap, quick and easy

[BRENT in 10-uh-C]

First question, are the spark plugs in order from #1 (L) - #4 (R)?

My initial observation is oil is possibly coming from the valves. The fuel mixture appears to be close based on spark plug tips. The carbon appears to following the suite of the combustion chamber which would indicate to me that it is originating from valve guide area and not piston ring. Typically you see more even spread of carbon around the entire piston top when it is the oil rings that are worn.

To totally diagnose this, it would be better to see the margin of the valves, the seat surface, check concentricity, and valve stem to guide clearance. I would also like to measure the bore with a feeler gauge to see how loose the piston is in the bore, etc.

[Licensed to kill]

no the plugs are not in order. Another observation, the head mimics the pistons in that the combustion chambers are black/sooty with a little bit of carbon buildup and the flat area is shiny but all had a light coating of oil. Also the carbon was "wet" on the head right above where the buildup is on the pistons.

[Licensed to kill]

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I pulled the valves. The guides were shot. I didn't take any measurements but they were quite sloppy. Without removing a piston, there is quite a bit of play at the top of the pistons side to side when I bring them up to the top. Not sure what to make of than as it seems to me that if the cylinders were wore it would show with a ridge at the top. Unless it was bored wrong or maybe this is normal for these engines, I don't know.

[30 Closed Cab PU]

Mic the cylinders top and bottom.



Just a guess. I've read that when cylinders are bored over, pistons have to be replaced with correct sized pistons/rings. Perhaps someone did not replaced the pistons.

[john charlton]

Just off topic slightly I have an engine with all compression reading just under 70 PSI but has heavy blow by at the oil filler so must be worn valve guides. I did not want to fit the extended oil filler gizmo as they aint pretty IMHO . I fitted the much larger model "B" filler and no blow by oil drops/mist and looks good too . I suppose in USA these "B" oil fillers could be difficult to find as not many 4 cylinder 1932 onwards cars were built . They can be found in UK as the "B" engine was built in Dagenham into WW2 . English "B" fillers are one piece construction not two piece as USA but have the same cap .

John in really lovely sunny hot spring weather Suffolk County England .

[Jack Shaft]

From a cost perspective the most expensive part of a rebuild is rod and main bearings,crankshaft and connecting rods.The cost of sleeving bores is up there too. Alot can be done to improve an engine that has decent rod and main bearings and minimal crankshaft thrust without getting too deep cost wise.In versely,a lot of time an money can be wasted trying to 'save' an engine with worn bearings..Engines need to be looked at as a whole,all processes must be in specification for long life,at .100 over with questionable bores and valves my next move would be a bearing inspection if it passes bearing inspection honing bores is a possibility if the bore measures correctly,lapping valves if the seats aren't too far gone,basically an old fashioned overhaul..

[Licensed to kill]

Originally Posted by 30 Closed Cab PU

Mic the cylinders top and bottom.



Just a guess. I've read that when cylinders are bored over, pistons have to be replaced with correct sized pistons/rings. Perhaps someone did not replaced the pistons.

I've never heard of someone boring a block and not replacing the pistons but that doesn't mean it didn't happen. Would be odd since pistons for these are so cheap but maybe it was someone that just didn't know??. You may be on to something there.

[Licensed to kill]

Originally Posted by Jack Shaft

From a cost perspective the most expensive part of a rebuild is rod and main bearings,crankshaft and connecting rods.The cost of sleeving bores is up there too. Alot can be done to improve an engine that has decent rod and main bearings and minimal crankshaft thrust without getting too deep cost wise.In versely,a lot of time an money can be wasted trying to 'save' an engine with worn bearings..Engines need to be looked at as a whole,all processes must be in specification for long life,at .100 over with questionable bores and valves my next move would be a bearing inspection if it passes bearing inspection honing bores is a possibility if the bore measures correctly,lapping valves if the seats aren't too far gone,basically an old fashioned overhaul..

My thoughts exactly. I have already checked the bearings as i had the pan off when I first got it to fix an oil leak and checked/adjusted all the bearings at that time. If the crank/rods/bearings are good the rest can be rebuilt very cheap. For now, I'm going to do the valve guides and see what that does for me. I'm not going to be putting a whole pile of miles on this so putting it back to perfect is not necessary. I just need it serviceable/drivable in reasonable condition. I'll mic the bores and see what I have in that respect. Perhaps, like 30CCPU suggested, it's been bored to .125 but has .100 pistons??. If that turns out to be the case, it's not a big job to change the pistons/rings and deglaze the cylinders. FWIW, I did a compression check when I got it and they were all in the high 50's IIRC. It was definitely using oil through the guides though so I'l fix that first.

[BRENT in 10-uh-C]

Originally Posted by Licensed to kill

no the plugs are not in order. Another observation, the head mimics the pistons in that the combustion chambers are black/sooty with a little bit of carbon buildup and the flat area is shiny but all had a light coating of oil. Also the carbon was "wet" on the head right above where the buildup is on the pistons.

Originally Posted by Licensed to kill

I pulled the valves. The guides were shot. I didn't take any measurements but they were quite sloppy. Without removing a piston, there is quite a bit of play at the top of the pistons side to side when I bring them up to the top. Not sure what to make of than as it seems to me that if the cylinders were wore it would show with a ridge at the top. Unless it was bored wrong or maybe this is normal for these engines, I don't know.

That is why I suspected & suggested worn guides.

Unless you have a decent selection of metrology, you are not going to be able to tell much regarding bore size and piston clearance.

The other thing you need to determine is just how far do you want to go with this project?

[Licensed to kill]

Originally Posted by BRENT in 10-uh-C

That is why I suspected & suggested worn guides.

Unless you have a decent selection of metrology, you are not going to be able to tell much regarding bore size and piston clearance.

The other thing you need to determine is just how far do you want to go with this project?

I'm not going to get TOO carried away as I doubt that I will put 5000 miles on this car in my lifetime. The car is not anything special. It's what you refer to as a "junk restoration". It's basically stock with many jobber parts and a few mods (second tail light and signals, want to maybe add a voltage regulator, that sort of thing). Basically your run of the mill $10,000 model a. If I can get it to stop useing so much oil and improve the brakes (maybe cast drums and learn to set them up properly), I'm a happy camper.

[30 Closed Cab PU]

Again am arm chairing here, but could swear I have read or heard when cylinders/rings are wore, some honed the cylinders and installed over sized rings to get by. You never know what farmer fixes have been done on a 90 year old car, by people going through tough times - some of what you refer to as a "Junk Restoration".

[Jack Shaft]

There isnt anything bad about building the car to meet what you want. Guides are cheap,so are rings and lapping compound. No engine will tolerate a piston .025 smaller than the bore,your 'slugs match your jugs'..dont worry about being able to wiggle the piston some,wall clearance is way better loose than tight.You know what to do...good luck..

[BRENT in 10-uh-C]

Originally Posted by Licensed to kill

I'm not going to get TOO carried away as I doubt that I will put 5000 miles on this car in my lifetime. The car is not anything special. It's what you refer to as a "junk restoration". It's basically stock with many jobber parts and a few mods (second tail light and signals, want to maybe add a voltage regulator, that sort of thing). Basically your run of the mill $10,000 model a. If I can get it to stop useing so much oil and improve the brakes (maybe cast drums and learn to set them up properly), I'm a happy camper.

Whoa, WHOA, ....W H O A!! I never called your car a "junk restoration"!!


Yes, it is often difficult to find a stopping place, but replacing guides & valves, re-ringing it, and tightening up the lower-end clearances should put you on your way to many happy miles.

[Licensed to kill]

Might be a while before i can get to putting it back together. Weather cleared and will be going back to work. Unwell report back when It's back together and i have a chance to drive it and check the oil consumption but I think Brent hit the nail on the head with the guides. I still don't get why the plugs are not fouled from that much oil consumption but we will see.

[Licensed to kill]

Originally Posted by BRENT in 10-uh-C

Whoa, WHOA, ....W H O A!! I never called your car a "junk restoration"!!


Yes, it is often difficult to find a stopping place, but replacing guides & valves, re-ringing it, and tightening up the lower-end clearances should put you on your way to many happy miles.

I was referring to a comment you made awhile back in a thread about a restored model A that was on eBay IIRC for $50,000. You're familiar with the car and were defending the price from those that thought the seller (the owner had passed away IIRC) was nuts. You had said something to the affect that "this is not your typical junk restoration". You were not referring to my car specifically but my car fits the definition of what you meant. I don't disagree and am not offended. There are "levels" of restoration and I would put mine in the average category. While I can appreciate the pristine cars, restored or unrestored, I want something that I am not afraid to drive so I'm OK with "junk restored". It looks good, drives good and as soon as i get this oil consumption fixed, runs good. It's all good. Like I said, I wasn't offended and understand what you meant. Not a bad description IMO.

[Jim Brierley]

Licensed, get modern straight-stem valves and guides, they are made to tighter tolerances and will seal better and last longer. Use guides with the step, that looks like original guides, the spring will hold them in place.

John C, blow by is caused by gases blowing by the rings, not valves.

[Benson]

PM sent

[john charlton]

Hi Jim

As the engine has excellent compressions on all 4 cylinders better than others I have who use very little oil and have no blow by I reasoned that it must be slack guides . On the exhaust stroke the valve pocket is pressurised and if room around the valve stem and guide I thought exhaust gasses could pass down into the valve chest hence pressurising the crankcase etc etc . So it would seem I am wrong so why the engine with very good compressions blows by all over the starter motor area remains a mystery !!!

John in same place same weather Suffolk County England .

[Jack Shaft]

One thing is sure about owner builder cars,there are some,especially among those who pay for professional restorations,that will look down their nose at you.The clubs establish unspoken 'pecking orders' based on the quality of restoration,with no regard to the owners participation in the actual repair.

[History]

Lol, you made me laugh with the pecking order comment. I lived in a golf course,country club for awhile. I don't golf but I also don't have anything against golf, I lived there purely as a business move. I worked for most of the people who lived there as I was an arborist at the time. I did the full range of tree services, pruning, removals, fertilization, pesticide, crane removals, stump removal,,,,,,,,,. At different gatherings or socials my wife and I would attend because it wasn't good for business and we felt like we needed to support the club. At a party one night I was standing in a corner listening and the hostess was asked by another lady, who had purchased a certain property, she leaned close to her and said with a disgusted look on her face "he's the manager of a furniture factory". We made eye contact just as she said it and me being the "tree guy" knew what she thought of me. It was great in one sense as no one who lived there was jealous of me, except my good looking wife and our younger age, otherwise they didn't care about us. We made great friends there who were real people with egos checked but some people like the lady I mentioned were actually sickening. Those people acted worse than high school "cool kids". I'm not the jealous type and am happy for anyone who prospers honestly, but that pecking order. lol

Originally Posted by Jack Shaft

One thing is sure about owner builder cars,there are some,especially among those who pay for professional restorations,that will look down their nose at you.The clubs establish unspoken 'pecking orders' based on the quality of restoration,with no regard to the owners participation in the actual repair.

[Licensed to kill]

Update. Installed new values and guides. "modern" type from brattons. Ground seats and valves to achieve a good seat and proper lash (don't have adjustable lifters). Car runs great. No more back firing on deceleration, runs much smoother at higher RPM and pulls reasonably well. That's the good news. The bad news is that the oil consumption is unchanged and that annoying slight "knocking" sound is still there (didn't expect the valve job to affect that anyway). After a 100 mile run, parked the car and after an hour or so was a spot of oil about the size of a golf ball under the bell housing. I expect there to be some but don't know if this is about right or too much or????. Gong to pull the pan again and recheck the bearing clearances in the hunt for the noise. Again though, perhaps this is just how a model A sounds , I don't know.

[chrs1961815]

In an ideal world, there should be no leaks but after chasing mine down and not fixing it, I have come to the conclusion that all Model A's leak a little.

Your rear main leak can be caused by many things - I assume your gaskets are all relatively new and hopefully you have the gasket between the flywheel housing and block. That is sometimes left out which causes a bad rear main leak.

I would figure out where the knock is coming from - if not from the crankshaft, it could be worn wrist pin bushings. But I would doubt that if the cylinders had very little wear.

[johnneilson]

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Originally Posted by john charlton

Hi Jim

As the engine has excellent compressions on all 4 cylinders better than others I have who use very little oil and have no blow by I reasoned that it must be slack guides . On the exhaust stroke the valve pocket is pressurised and if room around the valve stem and guide I thought exhaust gasses could pass down into the valve chest hence pressurising the crankcase etc etc . So it would seem I am wrong so why the engine with very good compressions blows by all over the starter motor area remains a mystery !!!

John in same place same weather Suffolk County England .

John,

Just a compression test alone does not indicate ring sealing. The issue of oil blowing out of the fill tube indicates that. Exhaust valve stem, sorry, no. But, a leak somewhere else could be the issue. I had a friend missing a front cover bolt and it did the same thing, bolt under generator covered the starter in oil.

In reality, the piston rings never seal completely. There must be a slight leakage through the rings to the oil ring to control the oil. Many articles on this subject written on web. I would also inject here that the ring package on the "A" is marginal at best, especially when driven at the higher RPM's.

Like the old saying goes, "if it is not leaking oil, it doesn't have any".

I make it a point to park outside of friends driveway, an on the driveway of those that aren't.

John, roasting in SoCal.

[john charlton]

The engine in question is in a 1930 standard roadster . It did have a hefty rear main leak one you could never park on a neighbours drive !!! I re did the crank clearances and now even after a long test run in the chassis very few drops now, it did surprise me it made such a difference . It was when during extended running I could see that the blow by was excessive so it would need the funky extension tube . I fitted a "B" filler and now no oil droplets escaping . I checked the compression with two different testers . One reads 65 on all four the other 68 could be of course these are old and not very accurate . I have a 31 CCPU which has 55 on all 4 but no blow by at all and uses very little oil . This engine has excessive endfloat I would guess at least 40 thou and yet no rear main leak I guess maybe not much crank case pressure . The proof will be in the pudding when I get the roadster on the road hopefully in about 6 weeks or so . Maybe the rear main leak will return ( I guess it will !!!)

John in summer seems to have left the building 60 f and rain mid July RATS
Suffolk County England .

[shew01]

Originally Posted by johnneilson

I make it a point to park outside of friends driveway, an on the driveway of those that aren't.

John, roasting in SoCal.

That’s hilarious. [emoji23] I make it a point to say off driveways of friends and foes alike. [emoji2957]


Sent from my iPhone using Tapatalk

[Benson]

My SEWAG on this:

See reference about a small oil leak in your post #24.

1. Did you know that one cause of rear main leaks is restriction of the breather pipe?

Be sure that the breather tube cap that you use does not have a "Scotchbright" Pad or similar stuffed in the cap or tube.

These pads have been the cause of at least 3 or 4 engine rebuilds.

One guy had an engine fail, he paid $3500 to rebuild a second.

He put the same OLD "scotchbright" cap on his new engine and 70 miles later the oil pan was empty!!

2. See Post 1 photo 3: You have a breather extension tube installed. If you look closely you will see that the flexible tube is about third the diameter of the the breather-tube.

3. This restricts the passage of crankcase fumes which increases back pressure in crank case which sometimes is enough to force oil from the rear main which has NO seal as designed by Ford.

4. Removing this device MIGHT slow down your rear main leak.

5, THERE ARE CHEAP repro BREATHER CAPS THAT WILL BLOCK the breather when the cap is slammed on after adding oil.

Originally Posted by Licensed to kill

Update. Installed new values and guides. "modern" type from brattons. Ground seats and valves to achieve a good seat and proper lash (don't have adjustable lifters). Car runs great. No more back firing on deceleration, runs much smoother at higher RPM and pulls reasonably well. That's the good news. The bad news is that the oil consumption is unchanged and that annoying slight "knocking" sound is still there (didn't expect the valve job to affect that anyway). After a 100 mile run, parked the car and after an hour or so was a spot of oil about the size of a golf ball under the bell housing. I expect there to be some but don't know if this is about right or too much or????. Gong to pull the pan again and recheck the bearing clearances in the hunt for the noise. Again though, perhaps this is just how a model A sounds , I don't know.

[Jack Shaft]

Originally Posted by History

Lol, you made me laugh with the pecking order comment. I lived in a golf course,country club for awhile. I don't golf but I also don't have anything against golf, I lived there purely as a business move. I worked for most of the people who lived there as I was an arborist at the time. I did the full range of tree services, pruning, removals, fertilization, pesticide, crane removals, stump removal,,,,,,,,,. At different gatherings or socials my wife and I would attend because it wasn't good for business and we felt like we needed to support the club. At a party one night I was standing in a corner listening and the hostess was asked by another lady, who had purchased a certain property, she leaned close to her and said with a disgusted look on her face "he's the manager of a furniture factory". We made eye contact just as she said it and me being the "tree guy" knew what she thought of me. It was great in one sense as no one who lived there was jealous of me, except my good looking wife and our younger age, otherwise they didn't care about us. We made great friends there who were real people with egos checked but some people like the lady I mentioned were actually sickening. Those people acted worse than high school "cool kids". I'm not the jealous type and am happy for anyone who prospers honestly, but that pecking order. lol

It has to do with your own skin brother,if your happy in it life is good,if your not no amount of money can save you

[Jack Shaft]

Seeping is tolerable,leaking is not..

[Licensed to kill]

Another update. I pulled the pistons and low and behold, the bore is a bastard size. .100 over pistons an the bores mic 3.986 (.011 over the proper .100 over bore size). Put a compression ring in the cylinder and found the gap to be somewhere around 1/4". And this thing used oil???, wholda thunk. So I'm now in the throws of deciding what to do about it. The bores are good, no taper and zero ridge so I'm thinking that who ever bored the block just plain did it wrong. Two of the piston were scored pretty bad, likely due to it overheating a couple times before i put a temp gauge in it and subsequently changed the rad. I did some experimenting on the old pistons and am considering two solutions (no, getting it rebored to .125 over is not one of them at this time).I can knurl the skirts on .100 over pistons and easily get them to an interference fit then gently emery the peaks to achieve the required clearance. This has the added benefit of lube retention on the skirts. The other way is to get .125 over pistons and turn them down a few thou to achieve the proper piston/wall clearance. This has the added benefit of being able to also turn the head portion to proper clearance. Either way I will get .125 over rings and file them to proper gap.I have the weekend to ponder before ordering pistons on monday. Any thoughts on either of these two options welcomed.

[40 Deluxe]

Originally Posted by Licensed to kill

Another update. I pulled the pistons and low and behold, the bore is a bastard size. .100 over pistons an the bores mic 3.986 (.011 over the proper .100 over bore size). Put a compression ring in the cylinder and found the gap to be somewhere around 1/4". And this thing used oil???, wholda thunk. So I'm now in the throws of deciding what to do about it. The bores are good, no taper and zero ridge so I'm thinking that who ever bored the block just plain did it wrong. Two of the piston were scored pretty bad, likely due to it overheating a couple times before i put a temp gauge in it and subsequently changed the rad. I did some experimenting on the old pistons and am considering two solutions (no, getting it rebored to .125 over is not one of them at this time).I can knurl the skirts on .100 over pistons and easily get them to an interference fit then gently emery the peaks to achieve the required clearance. This has the added benefit of lube retention on the skirts. The other way is to get .125 over pistons and turn them down a few thou to achieve the proper piston/wall clearance. This has the added benefit of being able to also turn the head portion to proper clearance. Either way I will get .125 over rings and file them to proper gap.I have the weekend to ponder before ordering pistons on monday. Any thoughts on either of these two options welcomed.

If you get new pistons, will they be cam ground, and do you have the capability to cam grind them to the proper size? Might be easier to go the knurling route. If the top grooves are worn, .030" spacers are available.

[johnneilson]

If the bores are as good as you say, round, no taper you may want to just buy some new ones made for the existing bores. This gives lots of options, ring package, lighter pins, add some dome.
Personally, if the bores are that far over I would be suspect of the quality of the machining. Are the bores straight in relation to the crankshaft and are they on the proper center lines. Have seen lots of good work and just as much not so good.

Best of luck, John

[Licensed to kill]

Originally Posted by Benson

My SEWAG on this:

See reference about a small oil leak in your post #24.

1. Did you know that one cause of rear main leaks is restriction of the breather pipe?

Be sure that the breather tube cap that you use does not have a "Scotchbright" Pad or similar stuffed in the cap or tube.

These pads have been the cause of at least 3 or 4 engine rebuilds.

One guy had an engine fail, he paid $3500 to rebuild a second.

He put the same OLD "scotchbright" cap on his new engine and 70 miles later the oil pan was empty!!

2. See Post 1 photo 3: You have a breather extension tube installed. If you look closely you will see that the flexible tube is about third the diameter of the the breather-tube.

3. This restricts the passage of crankcase fumes which increases back pressure in crank case which sometimes is enough to force oil from the rear main which has NO seal as designed by Ford.

4. Removing this device MIGHT slow down your rear main leak.

5, THERE ARE CHEAP repro BREATHER CAPS THAT WILL BLOCK the breather when the cap is slammed on after adding oil.

When I bought the car it had a horrendous oil leak. Pulled the pan and found that the drain pipe was not even there. The boss where it screws into was broken so I had to weld one on. Since the pipe was not rolling around in the pan, SOMEONE knew it was not there. Some of the things you discover in a 80+ year old car.

[Licensed to kill]

Originally Posted by 40 Deluxe

If you get new pistons, will they be cam ground, and do you have the capability to cam grind them to the proper size? Might be easier to go the knurling route. If the top grooves are worn, .030" spacers are available.

Excellent point. I came across this tidbit (pistons being cam ground) while researching after posting. Pretty much rules out turning them down. Found some interesting info regarding knurling though. I'm gonna give that a go. God hates a coward. Of course he despises an idiot so........