Engine Repair/Upgrade

[A400#221]

Greetings;
I need some advice and guidance from you guys who have remained active in this hobby for the last 40-50 years on how to rebuild/repair/upgrade my engine. It was bored out, and had new pistons and rods etc. The old time mechanic who did the work for me felt we didn't need to grind the crank, or redo the mains, (there were very few good babbitt shops at the time.) He used emery paper to return the rod journals to "round"; they were oval by .002-3". Everything was balanced at a speed shop. All this work was done for me over 45 years ago. It's a long story, but the car has never been finished and only has about 7-8 hours on the engine. There is a slight knock when the spark is advanced, which I suspect is a rod journal; upgrades are available now that weren't then, like pressure oil, inserts etc. I want to preserve as much of the value as possible from the work already done but suspect the repair to the crank was inadequate. Can it be welded up and reground to standard on the rod journals, and possibly .005" over on the mains? Would it be better to just bite the bullet and get it reground and go with inserts, or have the main bearings rebabbitted and buy new rods?
I've read most your scholarly discussions on inserts vs. babbitt, and am a veteran of many miles in Model A’s back in 60’s, including the 1962 Transcontinental Tour to the MAFCA meet in San Francisco. I drove a 1930 Town sedan as primary transportation for 4 years and doubt I’ll be hammering the engine like I did as a college kid trying to keep up with traffic on the New Jersey Parkway. Nevertheless, I remember that if you push the engine much above 48-52 for long periods of time it is on borrowed time. In about 35,000 miles I blew a rear main once and a center another time. Then again, these engines probably didn’t have factory babbitt, and poor tinning of the caps was suspected in both cases….(hence my attempt to save the factory mains on my original A-400 engine).
There are also lots of other wondrous improvements since I cut my automotive teeth and am wondering if there is a “best practices” clearing house for the pros and cons of all the marvelous inventions, like 12 volt, halogen bulbs, etc, or do you recommend just digging through the forum? That question may seem stupid to some, but I’ve had this project mothballed for so long, I don’t have much awareness of all that has changed in the last 45 years. I see lots of new stuff offered for sale, but don’t have the experience to tell gem from gimmick, or even what is acceptable from a judging standpoint. Your thoughts would be most welcome.

Thanks,

[LukeDahlinger]

I'm sure you'll get a reply from the engine folks who frequent this forum so I won't bother with that question.

As far as converting to 12 volt, I see no need for it. Most of the time they get converted to 12 volt for no valid reason. All of my A's are 6 volt with generators and will stay that way. If you stay with 6 volt I'd get the generator band mounted voltage regulator that's being sold, I have one and it works quite well.

I've never tried the halogen bulbs- I use resilvered original reflectors and 32-50cp bulbs and they are plenty bright.

In my opinion there's alot of accessory stuff sold for Model A's simply for the sake of having something to sell.

You can do a search of the forum and it would turn up alot of great info.

[Joop]

And this is the place to ask those Questions.


...

[George Miller]

Originally Posted by A400#221

Greetings;
I need some advice and guidance from you guys who have remained active in this hobby for the last 40-50 years on how to rebuild/repair/upgrade my engine. It was bored out, and had new pistons and rods etc. The old time mechanic who did the work for me felt we didn't need to grind the crank, or redo the mains, (there were very few good babbitt shops at the time.) He used emery paper to return the rod journals to "round"; they were oval by .002-3". Everything was balanced at a speed shop. All this work was done for me over 45 years ago. It's a long story, but the car has never been finished and only has about 7-8 hours on the engine. There is a slight knock when the spark is advanced, which I suspect is a rod journal; upgrades are available now that weren't then, like pressure oil, inserts etc. I want to preserve as much of the value as possible from the work already done but suspect the repair to the crank was inadequate. Can it be welded up and reground to standard on the rod journals, and possibly .005" over on the mains? Would it be better to just bite the bullet and get it reground and go with inserts, or have the main bearings rebabbitted and buy new rods?
I've read most your scholarly discussions on inserts vs. babbitt, and am a veteran of many miles in Model A’s back in 60’s, including the 1962 Transcontinental Tour to the MAFCA meet in San Francisco. I drove a 1930 Town sedan as primary transportation for 4 years and doubt I’ll be hammering the engine like I did as a college kid trying to keep up with traffic on the New Jersey Parkway. Nevertheless, I remember that if you push the engine much above 48-52 for long periods of time it is on borrowed time. In about 35,000 miles I blew a rear main once and a center another time. Then again, these engines probably didn’t have factory babbitt, and poor tinning of the caps was suspected in both cases….(hence my attempt to save the factory mains on my original A-400 engine).
There are also lots of other wondrous improvements since I cut my automotive teeth and am wondering if there is a “best practices” clearing house for the pros and cons of all the marvelous inventions, like 12 volt, halogen bulbs, etc, or do you recommend just digging through the forum? That question may seem stupid to some, but I’ve had this project mothballed for so long, I don’t have much awareness of all that has changed in the last 45 years. I see lots of new stuff offered for sale, but don’t have the experience to tell gem from gimmick, or even what is acceptable from a judging standpoint. Your thoughts would be most welcome.

Thanks,

I would think you would want to find out what the knock really is. I don't think it is a rod, although you are not going to make a crank that is .002 out of round, round with emery paper. Sounds more like piston slap to me.

[Arlyn Bieber]

Sounds to me like you need to bite the bullet and do a total rebuild. By that I mean counterbalance the crank, machine the cranks journals then have it balanced. Rebabbitt the engine, bore the cylinders to standard oversize or sleeve if bore is over 0.100". Install hardened valve seats on the exhaust valves, install modern valves with one piece valve guides and large intake valves. Install new "B" camshaft with adjustable lifters and aluminum timing gear. Cut down flywheel for early V-8 pressure plate then balance flywheel and pressure plate. Purchase one of the high compression cylinder heads. Install new exhaust manifold then bore out the intake manifold and run a "B" carburetor. Have your rods rebabbitted then balance the rods, especially the crankshaft end. Balance the rod and piston assembly. Ford was very picky about balancing all the engine components and for good reason. Make sure the mechanic you choose has experience pouring babbitt, there aren't many of us left that know how to do it right. If you do all this and the mechanic does a good job you will have an engine while run a long time at 55mph. Of course that assumes you have rebuilt the transmission and differential. And don't forget when you drive these speeds you need to stop the car which means new cast iron drums and complete brake rebuild. Save your money and resist the 12 volt system change just because "new" cars have 12 volt systems. Put that money into good brakes and you won't be unhappy. Good luck.

[Great Lakes Greg]

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Like LukeDahlinger, I agree that modern mechanical widgets all over diminish from the original purpose of the car. The primitive Model A is a work of art as it was designed. If you have upgrades on your "A", you certainly have every right, and some items like turn signals and seat belts absolutely have their place. I'll take mine plain in a vanilla wrapper.

[RichPA]

I personally like the idea of keeping the car as it was designed using the old technology.It was good enough back then and still works now, besides, its darned interesting. IMO, read and search this forum, its the best, then draw your own conclusions to decide what to do.

[A400#221]

If a total rebuild were something I would want to consider, I acquired a "B" engine with "C" crank back in '64. I would use that to build a serious touring engine, maybe even with Winfields and a Cragar OHV conversion. My goal now is to improve upon what I suspect may have been an ill-advised short-cut with the crank. Everything including the crank was dynamically and statically balanced at a speed shop, pistons, rods, flywheel, clutch disc, and pressure plate assembly. The pistons are identical weigh, as are the rods. There is VERY little vibration when the engine is running. I do agree that I need to pull it and determine the exact reason for the knock before I go further. By the way, I put cast iron drums on the front 45 years ago, also welded up the roller shelves, and installed new bushings throughout. I was hoping someone would say that they had good success welding up the crank and regrinding to standard. My concern is that welding might warp it and cause even more problems.

[James Rogers]

Originally Posted by A400#221

If a total rebuild were something I would want to consider, I acquired a "B" engine with "C" crank back in '64. I would use that to build a serious touring engine, maybe even with Winfields and a Cragar OHV conversion. My goal now is to improve upon what I suspect may have been an ill-advised short-cut with the crank. Everything including the crank was dynamically and statically balanced at a speed shop, pistons, rods, flywheel, clutch disc, and pressure plate assembly. The pistons are identical weigh, as are the rods. There is VERY little vibration when the engine is running. I do agree that I need to pull it and determine the exact reason for the knock before I go further. By the way, I put cast iron drums on the front 45 years ago, also welded up the roller shelves, and installed new bushings throughout. I was hoping someone would say that they had good success welding up the crank and regrinding to standard. My concern is that welding might warp it and cause even more problems.

Easier to find a good A crank than trying to destroy it by welding. See my website and you may want to contact me concerning a motor.
http://www.model-a-ford-4bangers.com/

[George Miller]

Originally Posted by A400#221

If a total rebuild were something I would want to consider, I acquired a "B" engine with "C" crank back in '64. I would use that to build a serious touring engine, maybe even with Winfields and a Cragar OHV conversion. My goal now is to improve upon what I suspect may have been an ill-advised short-cut with the crank. Everything including the crank was dynamically and statically balanced at a speed shop, pistons, rods, flywheel, clutch disc, and pressure plate assembly. The pistons are identical weigh, as are the rods. There is VERY little vibration when the engine is running. I do agree that I need to pull it and determine the exact reason for the knock before I go further. By the way, I put cast iron drums on the front 45 years ago, also welded up the roller shelves, and installed new bushings throughout. I was hoping someone would say that they had good success welding up the crank and regrinding to standard. My concern is that welding might warp it and cause even more problems.

You do not have to pull it to find out what it is. First short out each cylinder and find out if the noise goes away or changes. If it does you will know what cylinder it is. I would never take a engine apart and not know where the noise is coming from. It can end up, like looking for a needle in a hay stack.

[Scott Owens]

A well built Model A engine is all you need. A lightened flywheel, high compression head, touring grind cam, V-8 pressure plate all add to the enjoyment of driving. No one can look at my engine and tell it's not like it came from the factory. As for the emery cloth rounded journals, .002-.003 is like shim, no shim, shim, no shim...every revolution. I wouldn't think the babbitt would last long. A well built engine is the best money I have spent on my A. Call Dreamwerks. Nice guy too.

[Ian in Mississauga]

There is a shop near me that builds up cranks by chrome plating them. I have no personal experience with this, just a thought.

[rdscouple]

If it were mine, I would first try to determine the source of the noise using the methods described above. Then, disassemble it and if the babbit looks ok, plastiguage all the mains and rods and adjust if necessary. Then lap the valves, hone the cylinders, install new rings, and put it back together. If you don't abuse it, it will run good for many more miles. If you want to spend lots of money, full oil pressure is the best modification. Where I live, tours are on 2 lane country roads where we seldom go over 45 mph. The way Model As were meant to be driven.

[James Rogers]

Here is what you need. Insert rods and mains, 283 pistons at .100 over, Brumfield head, oversize intakes, touring cam. This one is gonna be a great touring motor.

[J and M Machine]

Clearly where the prior mechanic "sanded"the rod journals there's no guarantee he got them round.
With .002-.003" thousands clearance there's too much there. Typically a Model A should have.0015" that's a rule of thumb.
When the clearance grows,the knocking starts and the babbit is pounding out.

Someone had mentioned you would ruin a crank by welding,well that's not the case as we do it all the time. Clearly; it's a dollars and cents question since new counterweighted cranks are available it would be a better cost effective move rather than to weld up rods and mains of a stock Model A crank.

Clearly the solution to this problem would be to rebabbit the mains and rods and then grind or replace crank, Since everything else is ''rebuilt".


http://www.jandm-machine.com/crankshaftWelding.html

[Milton]

"Can it be welded up and reground to standard on the rod journals, and possibly .005" over on the mains?"

The engine in my sedan came from a builder in LA. The rear main inserts tried to seize because of inadequate oiling. In an attempt to repair the motor everybody came crawling out of the woodwork with this crank and that crank. All seemed to require some modification or other to match mine which used a modern rear seal. I took my wounded crank and had the rear journal metal-sprayed and turned back to standard. It is in the car now and so far no problems. Before I can say for sure though I want many more miles on it but, so far, so good.

[tamagrouchy]

My 28 had a knock that got worse when the spark was advanced. I did the shorting one plug at a time out and discovered my #2 Cyl was the culprit. Dropped the pan and noticed that I could actually move the rod. Long story short, you may just have 1 bad rod that you could change out or pull a shim on. Worst case, you may need to change that 1 rod out, but still cheaper than a complete rebuild and it should buy a few years of driving. Just my 2 cents. Harry K

[A400#221]

You guys are outstanding! I am delighted by your suggestions and as soon as the weather breaks will try the cylinder shorting trick to isolate the knock and go from there. I also loved the idea of plating the crank. They must have first ground the crank to make the plating was uniformly thick! The usual chrome plating routine is a copper strike followed by a few mils of nickle and finally the chrome. I'm sure you would need a uniform surface to start with so when ground to dimension the surface is all chrome. Has anyone else heard of this type of repair and are there any success stories? Thanks again for all your helpful suggestions.

[James Rogers]

Commercial chrome is done differently than decorative chrome. I don't think there are as many steps.

[jkcrosson]

Originally Posted by James Rogers

Here is what you need. Insert rods and mains, 283 pistons at .100 over, Brumfield head, oversize intakes, touring cam. This one is gonna be a great touring motor.

Looking good James. I am looking forward to get the engine back Saturday. You think we can get it in the car and going by Saturday PM??? LOL