Good and interesting topic the Alt Fuels.

Not intending to go to far off topic but years ago I had an 83 LTD (not CV but fox chassis) on propane. this was the from the factory as propone option. For a couple of years in the early mid-eighties, Ford offered propane just as they did a diesel on several models. The car was 2.3L 4CYL 4 door Fox bodied LTD and it had some comical traits. But it was phenomenally cheap to run $20 worth of propane (about 20 gallons) would take ya 600 miles plus. And it always started -40 no problem if you could turn the engine over it started. But it was gutless when it was cold , I'm not talking slow here but actually gutless. Once up to operating temp it actually had more get up and go than equivalent 2.3L gas units. But when it was cold out and the engine was cold (winter) forget about it. You would fire it up put it in gear put the pedal to the floor and ...wait and after a min or so once the engine got some heat in it the car would start to move. The other quirk was once every couple years it would blow up the muffler get just the right throttle position on deacceleration at just the right speed for the right length of time and you would fill up the exhaust system with what was mostly raw propane, then when you got on the throttle and would you get a whole exhaust system backfire complete with a 2-3ft flame out the tailpipe and a sound equivalent to a 105 howitzer going off. I had to install a fully welded heavy wall muffler after it blew up the first couple stock types. Needless to say the comedy aspect of it was worth it. Nothing like watching a whole block of people on the street hit the deck when it lit off. Mind you this was before 9/11 so it did not have the same connotations as it would today. The car was finally retired once body rot rendered it unsafe to drive in the late 90's. The engine and propane system lived on though as power plant for a portable sawmill. And is still being used to this day.

 

Very nice. I was under the impression you had to start them on gasoline the switch over to propane. The couple of trucks I've looked at were that way. Maybe has something to do with cold starts.

 

LOL!! Yes, "needless to say". One thing about propane or NG, the crankcase oil stays clean pretty much forever. I always thought the range aspect would be cool. Except there wouldn't be much room for anything in the bed. To be able to take a 2500 mile road trip without needing to ever stop for fuel would be pretty neat.

 

It comes down to how the system is designed. The issue with cold starting propane is the regulator/vaporizer will freeze up cutting fuel flow off before the engine starts to put heat into the coolant to keep the vapourizer heated. Ford had the vapourizer way oversized for the motor so the engine would start making heat (just) before it had a chance to freeze up and cut off fuel flow. The system was all off the shelf IMPCO components the Carb was a CA125 with the regulator/vaporizer being a model J I believe (can't recall exactly) and the fuel lock off a VFF30. The issue was the engine made zero power until it got some heat in it.
The engine was specifically built for propane with higher compression and I believe a specific LPG cylinder head sourced from Ford power products. Ford never advertised the HP rating of the propane motors but it was definitely more than the equivalent gasoline units, once it was up to temp.

When the car was finally retired it had 400K kms (250K miles) on it and the engine was a sound as the day it was built. I pulled the engine and the whole propane system hoses tanks ETC with the intention of stuffing it another fox body like a Mustang or a 4 banger Ranger, but after the system sat in the garage at the acerage for a couple of years, one of the neighbours out there that owns a landscaping business was looking for a new power plant for his small sawmill to replace the flathead Chrysler 6 that threw a rod, and he bought it. To this day it is still powering that sawmill and cost about half as much to run as the flathead 6 did.

 

I have always run high volume oil pumps in the past because that's what the old timers that taught me recommend, but with the 300 inline six I have always had trouble with the pump breaking the roll pin in the distributor or twisting the hex drive. My original 300 in my 84 f150 has 500,000 miles on it and I have replaced a broken distributor or pump drive rod about every 50k due to the added drag of the hv pump. I finally put a standard pump in at 380k and have not had a problem since. I have always run 10w30 oil and that's the only real trouble I have ever had other than those awful fiber timing gears that wear out and deposit their teeth in the oil pan.

 

Now that we have been forced back on track, lol, I guess I will ask related questions. What's the difference between high volume vs. high pressure? Is there a benefit to high pressure, it seems like all it does is create work. And how does oil viscosity affect those?

 

The current trend in racing is close bearing tolerances and light viscosity oils. 'Course, they tear down the engines constantly. High pressure output pumps are considered necessary in very high RPM engines. It's the bearing clearances that more or less determine the correct viscosity in terms of deviating from what the factory used. High pressure is not necessarily a good thing, from my reading it looks to me the lightest viscosity that has good pressure when hot, is kind of what you want. Excessively high oil pressure actually heats the oil up in of itself and can cause problems like oil shearing, and causes it to thin out. What's important is oil flow, another important consideration is the engine oil cools parts that are only indirectly cooled by the cooling system.

 

Oil pumps are a positive displacement pump for each revolution they will move a fixed amount of fluid. The amount or volume of fluid they move is directionally proportional to the speed the pump is turning.
Oil Pumps in an engine have a relief valve that will bleed off once it's setting is reached.
Note: the crank mains and the crank rod journals, do not actually ride on the bearings but on a film of oil between the crank and the bearing surface.

A higher volume pump will deliver more fluid volume for each rotation compared to stock one but the relief pressure is set at the same pressure as stock.
Where you would want to use a high volume pump is when you are running larger bearing clearances as this will move more fluid and be able to maintain a higher pressure with larger clearances.

A high-pressure pump may move the same fluid for each rotation as the stock one but the relife pressure will be set higher.
Where you would want to use a high-pressure pump is when you have increased bearing loading.
For example, if you double the HP of an engine or are running higher compressions the load on the bearings will have increased and you may have too much load on the bearing surfaces to maintain the oil film with the stock pressure to keep the crank from making contact to the bearing surfaces. Increasing the pressure of this film by increasing the system oil pressure allows for higher loading before the crank makes contact with the bearings. This is why most diesels run much higher oil pressures, due to the higher bearing loading. Engines that are worked hard (even stock ones) can benefit from a high-pressure pump to help increase bearing life.


So there are situations where you want increased pressures and situations where you want higher volume. If you have an engine with a little wear on it and are seeing low oil pressures at idle a higher volume pump will help get the pressure back up in most instances. Many Ford engines did not prioritize crank oiling so the cranks could starve from a lack of oil especially at higher RPM's and even more so on a motor with some wear, so in these instances, a higher volume pump will help ensure the crank receives adequate oil flow. The 335 Series engines are notorious for wiping out the bearings due to inadequate oil flow to the crank.

 

Btw, There's a trope about Women and their shoes, but take a walk down the motor oil aisle at any auto parts store and get back to me. Jeeze Louise!! I drove my slick all over for almost 20 years, never had a pressure gauge, relying on the idiot light. Never paid it too much attention, never saw it even flicker. Farm & Fleet 10w30. I'm told I need to worry about wiping a cam lobe, zinc extreme pressure additives have been removed.

So then I'm also told Diesel Oil is the stuff to use, if I don't want to buy boutique triple distilled "racing oil" at $17 a quart. So I start reading about "what oil to use" OK, no problem. I think. Rotella T is the stuff. Wait - no it isn't!! Yes it is! No it isn't!! It's just about as bad as with "what should my oil pressure be?" Replaced the oil pump on general principles recently and went down the Motor Oil Internet Rabbit Hole, trying to read up a little on this stuff, and have had quite enough.