Ford Blitz Restoration/Rebuild

[Hanno Spoelstra]

Just re-did my brakes:

new master and two rear cylinders;
refurbished front ones;
new rubber brake lines;
existing copper brake lines cleaned.

I choose to use DOT-4 brake fluid, have heard about silicone fluid leaking around seals and flared lines because of it's properties. I did not want to risk leakage and I am happy with flushing the system every two years or so.

HTH,
Hanno

[Private_collector]

Hanno,

The guy/s who told you about the leaking, were they the one it happened to, or the heard it from someone else scenario?

[Hanno Spoelstra]

Originally Posted by Private_collector

The guy/s who told you about the leaking, were they the one it happened to, or the heard it from someone else scenario?

Tony,

Heard it myself from first hand experience: the guy had to tin-plate his flares so they bedded-in better in the seats of the brake cylinders.

But if you renewed everything you'll be fine with silicone.

Hanno

[Private_collector]

My Ford stamp has arrived.
Ford stamp.jpg
I want to remove the oval, but fear my eyesight is not good enough to do cleanly.
A jeweller friend will shave it for me if I want him to.

Any tips on rebuilding the 11" Ford pressure plate assembly? New one is only $40USD, but another $70 or more to send. I dont believe mine is bad. I just want to examine all the pieces closely, before I feel it can be trusted enough to go into the engine.

I'm part way through a voyage of discovery with regards to oil flow in the French Flathead block. Because those engines were designed to run a governor and hour/rev meter, there are some openings above oil pump which I will be blocking off. On the weekend I will insert my borescope into the oil passages and compare the French block against an original Ford offering. Internally should be identical, so am just double checking route for the oil lines to & from external filter

[Tony Wheeler]

Originally Posted by Private_collector

On the weekend I will insert my borescope into the oil passages and compare the French block against an original Ford offering. Internally should be identical, so am just double checking route for the oil lines to & from external filter

Looks like you're right Tony, the only difference being the return pipe from the filter. Presumably it's designed to lubricate the governor drive gears before draining into the sump. Also they swapped holes for the oil pressure sender, presumably because it no longer fits in the standard position. Certainly the standard sender unit would not fit in that confined space.

It's interesting they stuck with the partial flow filter, despite this being the militarized block. If you have a look in the Ford manual you'll see they designed a full flow system for the CMP, with a bypass valve in case the filter became blocked. A bushing was inserted in the vertical passage to separate it from the horizontal passage, and a third passage was drilled for the oil filter return pipe, exactly where today's hot rodders drill the passage for conversion to full flow filtration. They seem to think they invented this mod, evidently they haven't heard of CMPs! Interestingly though I've never seen the full flow system on a CMP motor in Australia. It's always the partial flow system with the filter return pipe to the oil pan, and the third passage is always plugged. I wonder if they used the full flow system elsewhere, or whether it was abandoned for some reason. Certainly it's not necessary, and of course the rear main bearing and No.4 crankpin are fed directly from the oil pump anyway.

frenchflat.jpg

[Lynn Eades]

Tony the CMPs that used that system were the Carriers, not for a full flow filter, but for the oil cooler. (as with Aust. carriers) They had a bypass valve that let the oil by pass the cooler if it was too cold and thick. (later in the war the Canadians added a filter to that system in the Carrier, Universal, MkII*
I am sure you would already be aware, but the "partial' system you refer to is/was called a "bypass" system. The bypass system used a finer media in the element. it was supposedly to catch the very fine particles and was intended to stay in service for longer. Only a small percentage of oil from the pump was diverted through the filter. Often removing the lid, you would find them pretty much clogged up. I believe that any filter housing that you removed the lid to get at the filter was a bypass system. The British tended to use throw away steel bodied filters. Around WWII a bypass system was the standard filtration system common to most makes of the day.

[Shane]

A little off the subject mate, but could you please put up a picture of the fire extinguisher in your truck? Yours looks like the one i have and I would like to know if you believe this was the right one that was used in the CMPS. Cheers Shane

[Tony Wheeler]

Originally Posted by Lynn Eades

Tony the CMPs that used that system were the Carriers, not for a full flow filter, but for the oil cooler.

Lynn, the system I was referring to is the one shown in the CMP manual, not the carrier system with the oil cooler. It's described in detail in Section C. Lubrication and it's definitely a full flow system. They don't actually use the term "full flow" but the diagram and text are clear. It uses the standard filter housing which is bypassed in the event of blockage, by means of a bypass valve set to open at 10 psi pressure differential b/w the inlet and outlet: "If it were not for this valve any stoppage in the oil passages to and from the filtering element would prevent all oil reaching the engine."

As mentioned though I've never seen the filter configured that way. As you say they're designed as a bypass filter, dating back to the 1930s when they were fitted by Ford dealers as an optional extra. I believe that's the one with the oil return to the top of the motor, through one of the mounting studs on the rear of the inlet manifold for the fuel pump / breather stand. Presumably the drilled stud was part of the kit, which would have continued to be available throughout flathead production. In other words, just like the old NASCO kit for the Holden grey motor, which used the exact same filter housing, and was available from around 1950 until they introduced the red motor in '63. By that time the disposable spin on filter had been developed and it became standard equipment on all cars.

Presumably the optional filter on the flathead became military spec during the war, and they were introduced into production for the first time ever, with the return pipe subsequently redesigned to the oil pan. Once again of course it was a standard bypass system typical of the era. That's what makes the system described in the CMP manual so extraordinary. The idea of full flow filtration in 1942 was at least 20 years before it came into being on cars, and something even the hot rodders didn't develop as a flathead modification until at least 20 years later either. That's why I'm interested to know if anyone has ever seen it on a CMP as described in the manual. Certainly the third oil passage is commonly present on CMP motors, but it's always plugged in my experience.

Personally I suspect the full flow system was abandoned early in production, possibly including a field mod kit to revert to the bypass system. I can see a number of potential problems with the full flow system, particularly the bushing which separates the vertical and horizontal passages. That would constrict both passages severely unless they were drilled oversize first, which clearly wasn't done, because the thread size is standard throughout production, including CMP motors with the third oil passage. Even the Ford manual emphasizes the danger presented by sludge blockage, and that bushing would be the perfect place for it to lodge. Also as you suggest Lynn they probably required a coarser filter to accommodate full flow volume, which would mean less effective filtration of fine dust particles, which are the main enemy in military use. Then there's the bypass valve, which unlike the one on the carrier has the potential to destroy the motor in a few seconds if it malfunctions during a filter blockage, which was presumably not uncommon with the non-detergent oil in those days, plus the extreme dust conditions in military use, esp. in convoy, and the high dependence on frequent oil change and filter cartridge replacement. As you say Lynn they're invariably clogged when you lift the lid. That presents no problems with a bypass filter, it simply reverts to a standard flathead, and we know they ran for decades without an oil filter.

All things considered I can see no benefit in a full flow system in military use and plenty of potential problems. That's why I find it interesting the French continued with the bypass system on the militarized block, when they had every opportunity to drill a proper full flow system if they considered it of benefit. Clearly they did not, and they were obviously concerned with service life, as evidenced by the governor and hour/rev meter.

Of course, the debate still rages today in the hot rod community about the relative benefits of full flow and bypass flow systems on flatheads. Personally I reckon full flow is the ideal system for normal driving conditions, and the modern automotive industry obviously agrees. However they're producing vehicles expected to travel several thousand kilometers without engine replacement, and even a million kilometes in the case of taxis and transport vehicles, and with extremely long service intervals. That just wasn't the case in the old days, even in the '60s and '70s you were doing well to get 100,000 miles out of a motor, and that was with 3000 mile oil change intervals. All those oil changes kept me in a job for several years!

Therefore I see no point in a full flow system on our flatheads, or even in hot rods for that matter, because we simply don't do enough mileage to realize any potential benefit in terms of engine life, and we still need to change the oil just as often, because service intervals are time dependent as well as mileage dependent, and infrequent use and short trips call for more oil changes, not fewer. Most importantly though, as everyone knows, 90% of engine wear occurs during cold running at start up, and no amount of oil filtration can change that.