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-   -   Engine inspection (with pics) (https://www.fordbarn.com/forum/showthread.php?t=281668)

john charlton 05-28-2020 11:47 AM

Re: Engine inspection (with pics)
 

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 05-28-2020 01:35 PM

Re: Engine inspection (with pics)
 

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 05-28-2020 09:29 PM

Re: Engine inspection (with pics)
 

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


Quote:

Originally Posted by Jack Shaft (Post 1893010)
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 07-09-2020 07:57 PM

Re: Engine inspection (with pics)
 

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 07-09-2020 08:50 PM

Re: Engine inspection (with pics)
 

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 07-10-2020 02:59 PM

Re: Engine inspection (with pics)
 

Quote:

Originally Posted by john charlton (Post 1892978)
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 07-10-2020 03:58 PM

Re: Engine inspection (with pics)
 

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 07-10-2020 03:59 PM

Engine inspection (with pics)
 

Quote:

Originally Posted by johnneilson (Post 1907889)
I make it a point to park outside of friends driveway, an on the driveway of those that aren't.

John, roasting in SoCal.


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


Sent from my iPhone using Tapatalk

Benson 07-10-2020 04:19 PM

Re: Engine inspection (with pics)-Scotchbright Breather total oil loss-valve guides
 

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.





Quote:

Originally Posted by Licensed to kill (Post 1907662)
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 07-10-2020 05:06 PM

Re: Engine inspection (with pics)
 

Quote:

Originally Posted by History (Post 1893181)
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 07-10-2020 05:10 PM

Re: Engine inspection (with pics)
 

Seeping is tolerable,leaking is not..

Licensed to kill 07-10-2020 06:06 PM

Re: Engine inspection (with pics)
 

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 07-10-2020 06:54 PM

Re: Engine inspection (with pics)
 

Quote:

Originally Posted by Licensed to kill (Post 1907943)
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 07-10-2020 07:06 PM

Re: Engine inspection (with pics)
 

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 07-11-2020 06:55 AM

Re: Engine inspection (with pics)
 

Quote:

Originally Posted by Benson (Post 1907910)
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 07-11-2020 06:58 AM

Re: Engine inspection (with pics)
 

Quote:

Originally Posted by 40 Deluxe (Post 1907955)
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........:rolleyes::D


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