Inserted engine how is it holding up ?

B0B

Member
I am wondering how many miles some of you have on your Model A Inserted engines with the balanced crankshaft weights and other improvements have you had any problems and also what speeds do you drive ? My touring engine has 2000 miles on it and is running fine now with no problems ...I normally cruise at 40 mph and had it up to 50 for a few seconds once ...The only problem was with the crankshaft thrust bearing it failed with less than 200 miles on the rebuilt touring engine I took it out returned it to the rebuilder (Antique Engine rebuilders in Skokie ILL) and he installed a full circle thrust bearing and did a fine job it has been doing very well since ...So I am curious how the engines like mine are holding up and what problems guys have had and also what speeds they drive ...

1--MILES ?
2--problems ?
3--Driving cruise speed ?

HAPPY HOLIDAYS ! B0B in Michigan :)
 
On my inserted engine:
15,000 miles
No pressure oiling
No problems
Direct drive: cruising 50-55mph
Overdrive: cruising 60-70mph

No regrets, this car gets driven hard and on long trips that often include 'extreme' days i.e.: 500+ miles in a day, 100f + temps.

I have other A's that don't get driven like this, and get along just great with the babbit bearings.
 
I am wondering how many miles some of you have on your Model A Inserted engines with the balanced crankshaft weights and other improvements have you had any problems and also what speeds do you drive ? My touring engine has 2000 miles on it and is running fine now with no problems ...I normally cruise at 40 mph and had it up to 50 for a few seconds once ...The only problem was with the crankshaft thrust bearing it failed with less than 200 miles on the rebuilt touring engine I took it out returned it to the rebuilder (Antique Engine rebuilders in Skokie ILL) and he installed a full circle thrust bearing and did a fine job it has been doing very well since ...So I am curious how the engines like mine are holding up and what problems guys have had and also what speeds they drive ...

1--MILES ?
2--problems ?
3--Driving cruise speed ?

HAPPY HOLIDAYS ! B0B in Michigan :)

IMO, a floating ½ circle or horseshoe-shaped thrust should be perfectly adequate for these engines. For there to be a failure within 200 miles, something had to be aggresively creating friction, --or an inferior thrust bearing material was used. Otherwise with a full-circle thrust you would likely see the same issue arise in about double to triple the run time, --or in about 500-600 miles. I personally know of a few engines that were done back in the mid 80's with floating ½ horseshoe-shaped thrusts that probably have in excess of 50k on the odometer and those engines have never been pulled apart.


.
 
Bob,

1) 51,000 miles
2) No problems
3) Varies but most at 45-55 mph... but read on if interested

1929 Phaeton Body (light weight but with the top up, it is like pulling a parachute)
Early 1930 block inserted almost 10 years ago, mains and rods,
51,000 miles and no trouble…have not had the pan off yet
Original rear main seal system, modern style front seal. No leaks…none!
Replaced the head gasket @ 12,000 miles because I pulled the head to check for carbon build-up. Replaced the head gasket again at about 38,000 with a silicone style gasket due to a slight leak...no leaks since
Standard oil pump and oiling system with an A-Fordable (valve chamber cover) almost full flow oil filter
Counterweighted crank, lightened flywheel (40 lb), V-8 pressure plate
26% Mitchell overdrive, standard ratio rear end
5.9 Brumfield head
1.73" intake valves, 1.5" exhaust valves with rotators & hardened seats, touring cam, bronze timing gear with matched crank gear (was expensive as I recall)
Bored out intake manifold, performance tuned Zenith carb, standard exhaust manifold and standard Arries (sp?) stainless steel muffler, no engine pans
Full circle bronze rear thrust, 1/2 circle bronze front thrust w/ 45 degree bevel @ leading edge of thrust washer (helps build a little pressure on the oil as the crank spins)
.125 (by choice) V-8 GM style oversize pistons (Heaven forbid GM pistons in an A!)
Rods, pistons weighed and matched in weight
Crankshaft & flywheel/pressure plate balanced individually and then as one assembly
Largest cooling capacity pressurized Brassworks radiator with expansion tank.
I check the coolant level in the spring...rarely add any water/antifreeze solution.
Minnesota...Ya...You betcha for sure....50/50 antifreeze is required...IMO.
Nurex Electronic ignition, stock adjustment of advance on the timing, Nurex high output alternator, Halogens out front, LEDs @ the rear
Cast iron drums on all four...I keep them tight and tuned...
40-50 most of the miles
60-70 on the freeway many times
Held it at 75 mph on the freeway for 180 miles once (could have kept going but needed to stop for gas...really sucks the fuel at that speed) 20-22mpg @ 30-45 touring speeds
This engine has done everything I have ever asked it to do.
No signs of any problems yet...still has great power...still do not need to add any oil between the oil changes at 3,000 mile intervals.
I really like this engine! (I guess, you probably could tell that!)
IMO: The reason this engine has held together: All of the above but most importantly, the counterweighted crank, exhaust valve rotators and an overdrive to keep the rpms down at the higher speeds.

Good Day!
Dave in MN
For more info: www.durableperformance.net
 
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8000+ miles over 2 years, every day driving (55 - 60 mph) and hill climbs, no problems with Rich Falluca's inserted bottom end. 7:1 head, gravity/splash oiling with filter, 10w30 Mobil One.
 
The last 10 years or so at flea markets and car shows when I ran across guys that drove their cars I asked questions about their engines. When I say drove their cars, I am talking 30,000 to 100,000 miles on one car with no concern about running 55 MPH or more. Some had overdrives and most had some kind of higher compression head.


Babbitt or insert did not matter.

The common thread was a carefully balanced and assembled engine.

One guy I talked to was doing his second tightening of his babbitt bearings at 50,000 miles.

I have also found there are those who just have troubles. You could pick out the lack of details in the engine rebuilding process.

There are some horrible stories of inserts gone wrong and the block and crank were trashed. Babbitt failures rarely do that much damage.

The moral of the story:

You do not need insert bearings to get extremely long life on a car run 55+ MPH.

What you need is a person that knows how to properly rebuild the engine.
 
I'd concur with Brent and Kevin. I use a half circle thrust for my inserted engine, and it's on the rear main. Regardless of the bearing type and material, the machine work that's behind it is where the difference is made. I've seen bearings of both types fail, and succeed.
 
Full circle thrust...why it's needed...

IMO, a floating ½ circle or horseshoe-shaped thrust should be perfectly adequate for these engines. For there to be a failure within 200 miles, something had to be aggresively creating friction, --or an inferior thrust bearing material was used. Otherwise with a full-circle thrust you would likely see the same issue arise in about double to triple the run time, --or in about 500-600 miles. I personally know of a few engines that were done back in the mid 80's with floating ½ horseshoe-shaped thrusts that probably have in excess of 50k on the odometer and those engines have never been pulled apart.

Hi Brent, We are a bit off track of the original question here but lets go ahead...
You make a good point about some long running engines with ½ thrust systems…
Most insert engines I have worked on have 1/2 circle front thrusts and I agree that this is okay as this thrust is within the crankcase and constantly being wetted by the splash. The leading edge of the front thrust should be beveled to produce a bit of oil pressure as the crank spins to force the oil between the thrust washer and the thrust surface of the crank. Leaving it a sharp 90 degrees could actually wipe the oil from thrust surface of the crankshaft. See my second pdf for a view of the edge.

I agree good workmanship is very important but some of the failures may be due to the possible shortcomings of a 1/2 circle rear thrust. Early failure could be due to rough thrust surfaces on a crank, a thrust surface installed too tight (non-floating), severe driving conditions to name a few possibilities. I think we need to consider the full circle rear thrust benefits and possibly consider it a prudent practice even with good workmanship? Consider the following regarding a full circle rear thrust and why it should last much longer.
The following info is a mixture of my opinion and from information taken from conversations with Rich @ Antique Engine Rebuilding. (I use a lot of his components when rebuilding an engine.) Due to the most common practice of mounting the 1/2 circle thrust on the rear of the block (not cap), a 1/2 circle thrust runs a bit dry under certain driving conditions. With a 1/2 circle thrust mounted on the block much of the oil passing from the rear main bearing at idle dribbles between the cap and the rear thrust surface of the crank and is not passed to the thrust surface because it, simply, is not there. With a full circle thrust, all oil from the rear main must pass over a thrust surface and if both halves of the rear thrust surface are properly aligned it is then swept to all other thrust surfaces, keeping all surfaces lubricated and cool. Remember the original babbitt rear main had the same full rear thrust with matched surfaces. With rotation of the crank any passing oil would be distributed to all the remaining thrust surfaces. In a nut shell...there were no short cuts through the system allowing the possibility of leaving some surfaces dry!

{QUOTE} "something had to be aggresively creating friction" From my understanding, most of the 1/2 circle thrust failures happen in "Parade" driving conditions. (Low rpm with the clutch pedal down.) With a “dry” thrust, holding the clutch in builds a lot of heat between the rear thrust surfaces.

Further into my full circle thrust comments...actual components...I think are best. (My opinion, granted.)
I believe the one piece combination bronze thrust and seal is a better system than the original aluminum seal and 1/2 bronze thrust washer.
See the attached pdfs

With the one piece combination bronze thrust and seal, oil is held closer to the thrust surface and at any rpm some of the oil thrown to the seal area (groove) will come back down to the thrust surface. The multi piece system has a void between the outer perimeter of the thrust washer and the aluminum seal that allows the oil to drop to the cap without being drawn back to the thrust area.

Mostly my opinion on this stuff….but I spent a lot of time refining the full thrust system I am describing about 3 years ago and feel it is worth the effort to install.
FWIW: Rich, at Antique Engine Rebuilding, recently started installing a full circle rear thrust in all of his rebuilds also. Bob (from the original post) must have received his engine from Rich prior to the change. I have 51,000 miles on my engine and also have 38 others out with the full circle thrust....no problems and lots of parades.
Good Day!
Dave in MN
 

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Re: Full circle thrust...why it's needed...

. . . Early failure could be due to rough thrust surfaces on a crank, a thrust surface installed too tight (non-floating), severe driving conditions to name a few possibilities. . .

Nice discussion, Dave, and super pictures on your pdf's! I find it interesting that the present thinking for those bronze pieces is to pin them in just one place, leaving some "float". Could you expand on why you are in that camp? Neither original cast in place Babbitt or modern engines with inserts designed to include thrust surfaces have floating thrusts.

I wonder how the bronze would hold up if it had a few waves (oil ramps) in the surface and it were tinned with a few thousanths of Babbitt.

Here's a picture I came across of a modern center insert with an integral thrust surface. Of course, an external (to the crankcase) Model A thrust will never see as much oil.

11380Saturn0587.jpg
 
"1--MILES ? No more than 4 miles
2--problems ? NONE
3--Driving cruise speed ? " Slightly over 100 mph.

The last inserted B engine I did is still going strong.
It is in a vintage front engine dragster running 100% nitro.
It probably has about 10 to 12 runs on it.(Maybe more)
It turns a little over 100 mph and in the high eleven second range.
It won the Antique Nationals a couple years ago.

The reason I'm telling you who don't care about all this is, these engines
will last a LONG time properly put together.
Drive it and don't sweat it.
 
Bob,

1) 51,000 miles
2) No problems
3) Varies but most at 45-55 mph... but read on if interested

1929 Phaeton Body (light weight but with the top up, it is like pulling a parachute)
Early 1930 block inserted almost 10 years ago, mains and rods,
51,000 miles and no trouble…have not had the pan off yet
Original rear main seal system, modern style front seal. No leaks…none!
Replaced the head gasket @ 12,000 miles because I pulled the head to check for carbon build-up. Replaced the head gasket again at about 38,000 with a silicone style gasket due to a slight leak...no leaks since
Standard oil pump and oiling system with an A-Fordable (valve chamber cover) almost full flow oil filter
Counterweighted crank, lightened flywheel (40 lb), V-8 pressure plate
26% Mitchell overdrive, standard ratio rear end
5.9 Brumfield head
1.73" intake valves, 1.5" exhaust valves with rotators & hardened seats, touring cam, bronze timing gear with matched crank gear (was expensive as I recall)
Bored out intake manifold, performance tuned Zenith carb, standard exhaust manifold and standard Arries (sp?) stainless steel muffler, no engine pans
Full circle bronze rear thrust, 1/2 circle bronze front thrust w/ 45 degree bevel @ leading edge of thrust washer (helps build a little pressure on the oil as the crank spins)
.125 (by choice) V-8 GM style oversize pistons (Heaven forbid GM pistons in an A!)
Rods, pistons weighed and matched in weight
Crankshaft & flywheel/pressure plate balanced individually and then as one assembly
Largest cooling capacity pressurized Brassworks radiator with expansion tank.
I check the coolant level in the spring...rarely add any water/antifreeze solution.
Minnesota...Ya...You betcha for sure....50/50 antifreeze is required...IMO.
Nurex Electronic ignition, stock adjustment of advance on the timing, Nurex high output alternator, Halogens out front, LEDs @ the rear
Cast iron drums on all four...I keep them tight and tuned...
40-50 most of the miles
60-70 on the freeway many times
Held it at 75 mph on the freeway for 180 miles once (could have kept going but needed to stop for gas...really sucks the fuel at that speed) 20-22mpg @ 30-45 touring speeds
This engine has done everything I have ever asked it to do.
No signs of any problems yet...still has great power...still do not need to add any oil between the oil changes at 3,000 mile intervals.
I really like this engine! (I guess, you probably could tell that!)
IMO: The reason this engine has held together: All of the above but most importantly, the counterweighted crank, exhaust valve rotators and an overdrive to keep the rpms down at the higher speeds.

Good Day!
Dave in MN

Who built your engine?
 
Inserted engine, counterbalanced crankshaft, 35 lb. flywheel with V8 pressure plate, Sayder 5.5 head, modern valves, guides and lifters.

2500 miles
50-55 MPH when road permits
No problems
This touring engine was built by Reed's in Turlock, CA.

Ron
 
What are valve rotators and where do you buy them? Got a picture?

Lots of good tips here... I currently have my Model A's engine apart... and want to go back together with parts that will last!

Sam
 
I bought my one modified engine in 1998 from Phil Andrews who built B engines in central California. It was built to racing standards with oil pressure and big beefy main caps. It's got about 20,000 miles on it and I expect it to outlast me. It's in my 1930 deluxe delivery tour car and I run an oil filter with 20/50 Valvoline synthetic oil. It's been a great touring engine but I still love stock Model As
 
What are valve rotators and where do you buy them? Got a picture?

Lots of good tips here... I currently have my Model A's engine apart... and want to go back together with parts that will last!

Sam

GM (or Chevy) 11/32 dia valve rotators that replace the retainers of a standard straight stem valve. The valve springs need to have about .100" more room to compress to allow the extra mass of the rotator. Used on the exhaust valves only in my engine.
Good Day!
Dave in MN
 
Re: Full circle thrust...why it's needed...

Nice discussion, Dave, and super pictures on your pdf's! I find it interesting that the present thinking for those bronze pieces is to pin them in just one place, leaving some "float". Could you expand on why you are in that camp? Neither original cast in place Babbitt or modern engines with inserts designed to include thrust surfaces have floating thrusts.
Reply: Thanks for the nice comments regarding the pictures.
The "float" info is from Rich @ Antique Engine Rebuilding. He strongly suggested it due to early failures (pre-mature wear) on some fixed installations. His comment when asked as to why: The block often has a few holes in the rear main factory bore from the babbitt staking. The machining of the block counterbore varies a bit at these holes due to cutter chatter and if there were a high spot in the machining, an end loading condition could develop and take the thrust out. Allowing a bit of float allows the thrust washer to even out. A side advantage is that it is easier to install. (No tapping and screwing to the block.) dg

I wonder how the bronze would hold up if it had a few waves (oil ramps) in the surface and it were tinned with a few thousanths of Babbitt.
I think the oil ramps would work fine on the front thrust. I don't think I would want them at the rear thrust as the oil would have an "easy" path out. When I install the lower thrust washer floating, I technically have a slight oil ramp at the parting line between the two components. Babbitt surface...w/b fine I think! dg

Good Day!
Dave in MN
 
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Re: Full circle thrust...why it's needed...

Nice discussion, Dave, and super pictures on your pdf's! I find it interesting that the present thinking for those bronze pieces is to pin them in just one place, leaving some "float". Could you expand on why you are in that camp? Neither original cast in place Babbitt or modern engines with inserts designed to include thrust surfaces have floating thrusts.

I wonder how the bronze would hold up if it had a few waves (oil ramps) in the surface and it were tinned with a few thousanths of Babbitt.

Here's a picture I came across of a modern center insert with an integral thrust surface. Of course, an external (to the crankcase) Model A thrust will never see as much oil.
11380Saturn0587.jpg

Mike, the thrust bearing you have is a design that is very good for the motor it goes in, but as Dave says, that design will not work in a Model A, unless you can seal the rear up tight. The design that would work, is rather then have the groves go from inside, to out side at the same depth, you start at the depth that you have there, and taper to nothing, and stop about .030, to .040 thousdands before the out side edge, so it will be an Oil Well, not an oil escape. Many, about 30% of the late 1930's, on up have that design. The model A would only use two groves on each of the four halfs, front, and rear both. There would be two groves, and divided in 1/3's on each half. I have been using those kind of groves, on Model T, A, B's anothers for years. With out machine cutters, you can use a chain saw file. and you can't tell it from factory. We set thrust at .003-50, and never over .004. Many of the engine inserts we rebuild, do not have babbitt on the thrust face, if they are brass, if they are a steel insert, they always have Babbitt on the thrust. We do put babbitt on a rebuilt thrust insert, as we have to add what is worn away. thanks Herm.
 
Herm,

Is this type of thrust oiling workable even though they only did it on the front thrust?

Would it work on rear thrust?
 

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