? Of Mopar Flathead Reliability

[1950 Special Deluxe]

When I was a kid, my buddy had a 54/55? dodge flathead, and he always said,

" if somebody walks by with an ice cream cone it won't start".

[55 Fargo]

Mines got it's original 1955 dealer installed block heater.it works great,  I think with a block heater, decent thin oil, she may fire up good in cold weather. A lot of people used battery blankets up here too, keeps the battery warm, as long as you can plug it in.

Out rural in the old days, bring battery in the house, put wood stove embers ina metal pan and slide under the oil pan....

[48ply1stcar]

Through a rod after owning my (that green one) car 7 days in 1968.  No one told me at 16 that I had to fill the oil and check the gas.  Purchased a 53 flathead for $35.  Parked the car in 1970 when I joined the Army.  Started working on the car after retirement in 95.  Removed the head, scrapped the valves and the cylinder heads with a putty knife.  Only pulled the engine in 2012 after a I got a kick back from the County for mosquito control.

[55 Fargo]

I dunno you guys, Bombardiers out on the ice, used Chrysler flathead 6s, Taxis, but they were probably never shut off.

I have started mine easily in temps close to 0f a few times.

Now I want to hear from those old enough to have had to use these engines in cold weather climates...

Edited December 3, 2015 by Fargos-Go-Far

[55 Fargo]

Through a rod after owning my (that green one) car 7 days in 1968.  No one told me at 16 that I had to fill the oil and check the gas.  Purchased a 53 flathead for $35.  Parked the car in 1970 when I joined the Army.  Started working on the car after retirement in 95.  Removed the head, scrapped the valves and the cylinder heads with a putty knife.  Only pulled the engine in 2012 after a I got a kick back from the County for mosquito control.

That's still very cool, your car from your youth, driving and on the road today..

[Oldguy48]

I really believe that the issue was the ignition system.  If HEI ignition systems would have been available back then, there probably wouldn't have been a problem.  But between points type ignition system, and 6 volt electrical systems, and molasses slow starters, there truly was a problem.  Others may disagree, but I've lived it, and experienced it.  You'll not change my mind.  I'm a Mopar flat head fan, but  cold weather starting was not one of their strong points.

[dpollo]

Power loss Power gain :   Usually power loss is so gradual it is not really noticed unless there are burned valves or low compression.

Even a significant build up of carbon especially if the backs of the intake valves are coked up results in power loss.

Power gain is always noticeable because all the settings are on spec and if a rebore has been done there is more displacement and a slight increase in the compression ratio due to the bigger bore and possibly the milling of the head.

 

My first encounter with power gain was on a 40 Plymouth which popped the head gasket between 3 and 4 .  It had been running well before this all happened.  After a hard run I noticed white smoke from the exhaust. I removed the radiator cap. The coolant looked normal but all of a sudden the tide went out and even more suddenly my curiosity was rewarded by a face full of hot antifreeze.

After the gasket change, the engine seemed to have a lot more power.   Up to that point , since I had never had to add water, and the coolant was clean I do not think that compression was low due to gasket leakage.

[Ward Duffield]

Hello

I started driving MoPar flathead 6s in 1971. Many cars, Chrysler, Plymouth, DeSoto.

No comparison to those crappy stovebolts with splash rods and 5 psi oil pressure at an idle. Never could keep one of those alive at 60 mph.

I took many trips NY to FLA at highway speed .

These were my only cars for over 20 years, driven year 'round. Blew one engine when the flex hose to the firewall for the oil pressure gauge burst. DO NOT trust NOS in this vital application!

Had to do ring jobs rarely, tappet adjustments very rarely.

Broke one piston in the mountains of WV one night in a blinding rainstorm (Hmm, do we climb this hill, or let the wipers work?) but who knows what the DPO (Dreaded Previous Owner) had done or not done.

The big engines will reach around 100 mph with no damage, on occasion.

Of course, now that these cars cost as much as they do, I never would wind one up like that.

So, all in all, I feel these are good, reliable engines. I have one of each today. I run Rotella oil, and alcohol-free gas.

[46Ply]

Dad used to get up about 2 am, go out and warm the engine up a little during the night, so he could be sure that it would start when he went off to work the next morning.  (back in the 50's)

 

That was a '47 DeSoto with a well worn engine.

[Reg Evans]

I use to drive a 47 Dodge 1/2 ton in the 90's daily.  it had a transplanted 236 25" truck engine.  Sometimes during the rainy season and no garage I would have to bring out the hair dryer to dry the inside of the distributor cap before it would start.  Never had that problem in the mid 60's with my '33 Plymouth.

 

[Don Coatney]

I use to drive a 47 Dodge 1/2 ton in the 90's daily.  it had a transplanted 236 25" truck engine.  Sometimes during the rainy season and no garage I would have to bring out the hair dryer to dry the inside of the distributor cap before it would start.  Never had that problem in the mid 60's with my '33 Plymouth.

Must have been fun to drag that hair dryer out to the garage.

 

[Reg Evans]

No garage then Don.  I had that setup you showed under a shade tree where I did hair and automobile wrenching.

[Don Coatney]

No garage then Don.  I had that setup you showed under a shade tree where I did hair and automobile wrenching.

Merkins?

[Reg Evans]

Oh !!!!!..... I only worked on them in the back seat.

[Plymouthy Adams]

Don Coatney, on 03 Dec 2015 - 11:30 AM, said:

Merkins?

you hitting below the belt now Don...

[55 Fargo]

you hitting below the belt now Don...

Hey Tim, thought you would at least share your experience with your flathead 2 sp automatic with us?

Or are you now a dedicated more contemporary V8 guru?

[Plymouthy Adams]

Fred..this information I have posted a couple time on here already and most should know my results and experience.....I have no problems with my flathead and how it performs...speed limits in my neck of the woods are often just a "not to get run over speed"  pumping 10-15 over is common...so to say 80 sustained is not a problem...on normal cruise I go 75 and the only thing the engine screams is "give me more"  I am however uncomfortable at the float of the suspension at above 80...I have on hand but not done the shock relocation that would remedy the floating...fits in the category of don't fix nothing that works and it and the disc brakes kit are in the same box for that "eventual day"  at the moment, I have a person inquiring about purchasing the car..

 

As for the conversions..that is my fun thing to do and I buy my cars with no drivetrain installed on the average...I have no qualms or remorse cutting these cars..trust me..there are way enough originals and too few museum for them to be housed...

[55 Fargo]

Fred..this information I have posted a couple time on here already and most should know my results and experience.....I have no problems with my flathead and how it performs...speed limits in my neck of the woods are often just a "not to get run over speed"  pumping 10-15 over is common...so to say 80 sustained is not a problem...on normal cruise I go 75 and the only thing the engine screams is "give me more"  I am however uncomfortable at the float of the suspension at above 80...I have on hand but not done the shock relocation that would remedy the floating...fits in the category of don't fix nothing that works and it and the disc brakes kit are in the same box for that "eventual day"  at the moment, I have a person inquiring about purchasing the car..

 

As for the conversions..that is my fun thing to do and I buy my cars with no drivetrain installed on the average...I have no qualms or remorse cutting these cars..trust me..there are way enough originals and too few museum for them to be housed...

So now you are selling your only flathead powered automobile? I dunno, where's the fun in that, guess you can always ride around with Don, when you feel like a flathead ride.....

[Plymouthy Adams]

Fred..where in the name of sam did you get the idea this is my only flathead powered car....?   Still a number of cars in the barn with a flathead..even a straight 8 on the place..  Yes, last month or so I sold my flathead powered 58 Dodge truck...these cars and trucks with their flatheads are not anywhere near a rare or hard to come by commodity..there is nothing wrong with having old and new...original is just a maintenance of bolt on replacement parts..no fun in that, see no challenge and yes you can do other things but money in for performance return is not interesting to me, I rarely will pump a stock V engine.....it is the alternate build that is the fun for me...nothing else..you ought to try it sometime....

Edited December 3, 2015 by Plymouthy Adams

[55 Fargo]

Just had the impression you only had the Plym with the flathead and 2spd auto running. Yes it is sometimes much easier to build something from scratch with a modern drivetrain, especially since you are not as fond of the flathead powered vehicles

You might as well sell them, so others can enjoy them, and glad they have gone or will go to good homes.

Flatheads are not for everyone I suppose....

[meadowbrook]

As an engineer in the auto industry, I can tell you that modern engines are certainly long lasting and undergo more stringent testing that those of the past. But I would never call my 230 fragile. I suspect your friend has seen lots of old engines fail because they are old, usually at the end of their useful lives so it's natural that more of these would be failing in his experience.

[Plymouthy Adams]

Fargos-Go-Far, on 03 Dec 2015 - 4:33 PM, said:

Just had the impression you only had the Plym with the flathead and 2spd auto running. Yes it is sometimes much easier to build something from scratch with a modern drivetrain, especially since you are not as fond of the flathead powered vehicles

You might as well sell them, so others can enjoy them, and glad they have gone or will go to good homes.

Flatheads are not for everyone I suppose....

Fred...just about ever since you have hit the forum you have made mention of a 318 drop in, time to step up to the plate and soldier ahead.  I have never cut an old car that was truly a candidate for original refinish, I choose the ones that are pretty well shot and most here would even discount as a parts car purchase.  I also cringe when one cuts an excellent example for modern upgrades.  Often it is best to leave things status quo if those owners do not have the time, shop space and tools and fabrication skills to bring it all together, space to work and areas to store panels is a premium on this type of build.  Of course there is the farming out route one can take if they have deep pockets..but then, most anyone can buy a car.  The reason the flathead is not around any longer is that it was doomed from the start for advancement into the future by design...it however did perform within the era of design better than most other powerplants available...still a work horse engine..if you only plowing one row at a time and a shallow furrow.

[55 Fargo]

Fred...just about ever since you have hit the forum you have made mention of a 318 drop in, time to step up to the plate and soldier ahead.  I have never cut an old car that was truly a candidate for original refinish, I choose the ones that are pretty well shot and most here would even discount as a parts car purchase.  I also cringe when one cuts an excellent example for modern upgrades.  Often it is best to leave things status quo if those owners do not have the time, shop space and tools and fabrication skills to bring it all together, space to work and areas to store panels is a premium on this type of build.  Of course there is the farming out route one can take if they have deep pockets..but then, most anyone can buy a car.  The reason the flathead is not around any longer is that it was doomed from the start for advancement into the future by design...it however did perform within the era of design better than most other powerplants available...still a work horse engine..if you only plowing one row at a time and a shallow furrow.

Yes, well I do have the very Powerplant you mention, however have not made a final decision on whether it should be transplanted into my Fargo or not.

If not another project will develop at some point in time, not a big deal.

Fabrication skills for what I am planning are not overly intensive, but do not claim to "Know it all"..

Yes the flathead has been discontinued for many years, but the legend lives on, if they were not a very good powerplant, they would not operate in the modern world.

Glad you are enjoying the thread, good luck on your Hotrod project....

[Plymouthy Adams]

only reason I am at this thread and made an entry was that a member sent me the link in a PM where you had asked me directly why I had not weighted in...if that would not have been sent to me in that manner I would not have known the question was put forth...sorry...but I do not always read all threads...only those that interest me...going on about the flathead like this just makes little sense...if you have run and keep it up there are things that need be done in routine maintenance...common sense stuff and part of ownership regardless of engine make or model..does not have to be rehashed every day in some form or another..

[Captain Neon]

It's all perspective.   I work part-time at O'Reilly's in the evening and on weekends.  I don't know how many times some one will come in and tell me, "Just give me the cheap stuff.  It's just an old 5 year old car any way."

 

For most people everything is disposable: cars, employees, jobs, spouses, etc.  I work with a guy who claims to be a parts expert, swears by K&N OIL filters, and had never heard Fram Extra Guard oil filters referred to as an "Orange Can of Death" until last night.  Most people simply have no perspective and can only regurgitate what their friends post on Facebook. 

 

My newest vehicle, the wife's car, is six years old and am only considering getting rid of it because the boys in car seats are going to get cramped in the backseat soon.  They would be fine were it not for those government-mandated car seats.  I still always get the premium upgrade parts whenever possible for my '97 Neon!