I recall my old Kaw Z1/KZ engines had a about 5psi hot even with 20/50 oil... we were killing turbos weekly until we switched to Castrol Syntec. The Suzuki GS stuff was much better. Anyone know what type oil pressure our FJ's have hot/cold?
WAT 5psi Man T150 and rocket3 owners would loose their mess if they ever saw this on their OPG.
Quote from: turbocamino on September 21, 2022, 08:43:52 AM
I recall my old Kaw Z1/KZ engines had a about 5psi hot even with 20/50 oil... we were killing turbos weekly until we switched to Castrol Syntec. The Suzuki GS stuff was much better. Anyone know what type oil pressure our FJ's have hot/cold?
it should be about 50 to 65 psi on the oil-cooler circuit and 65 to 85psi on the main galley circuit not sure if it that numbers is on cold or hot engine but i guess operating temp
Wow,thanks..didn't expect anything close to that..are you sure?
I did check a workshop manual i have ,but the pages about oilpressure was missing (of Course) =) i checked earlier when i rebuild the engine a couple of years ago. But i have a haynes manual too and here is a picture from that manual specs they are alomst the same ,but i think it is something wrong in the haynes since it says relief valve opening pressure
The by-pass valve opens to "by-pass" the oil filter if it is hopelessly clogged. The idea is to wipe out the bearings with dirty oil vice wiping out the crank and rods with NO oil!
The relief valves are the small cylinder shaped items in the main oil galley in the engine case and the oil cooler galley in the oil pan. You can disassemble these to add a washer on top of the spring to increase the pressure. But then you need to consider restricting flow to the mains and rods to ensure the cams get the additional oiling.
I should also add - the relief valve pressure is the maximum you could see. I don't think it is anywhere close to that - especially with hot oil - and especially at or near idle. I remember talking with Randy a good while back about monitoring oil pressure. His response was something to the effect that it would be lower than you think and would only worry you. So I pretty much take the FJ oiling system on faith!
I actually have an Oil Pressure sensor on Casper. I installed the sensor in the Oil galley port on the left side of the engine, just below the ignition cover.
On a cool morning start up with full choke, it will read upwards of 80psi. Once warm and choke off, it will read about 55psi while riding at 70mph. At idle it will drop down to about 5psi.
1st photo shows the sensor location,
2nd photo shows PSI at a cold start idle
3rd photo shows PSI warm at idle
Fred
Thanks for the number Fred!
Yup. We had a lot of engines built and put into race cars, or people just buying a legends or roadster and they would call worrying about the psi being 5 or less lbs once warm.
70psi swing is considerable ..once the pump is spinning its certainly doing a job. Thank for all the info. I feel better about moving away from thick oils now.
When starting up a cold engine, Do you blip the throttle up to about 4k rpm every couple of seconds? I do this just to make sure higher pressure oil makes it to all the right spots.
No..my theory on a cold start would be go easy until cold oil circulates some. My choke dictates all that,,which is about 1500rpm.
Quote from: turbocamino on September 26, 2022, 03:39:18 PM
No..my theory on a cold start would be go easy until cold oil circulates some. My choke dictates all that,,which is about 1500rpm.
Agreed!
I'll third that. There is a reason the oil pressure is so high on a cold start. It is because the oil is thick. I would venture to say that revving the motor when cold would not allow the thick oil to flow where it needs to as quickly; even with the higher oil pressures, thus starving the bearings and such for oil and causing early wear for no reason.
I am not this anal but we used to race with a guy that would start his Chevy duramax and let it idle for 30 minutes before he even put it in gear to move it. He had close to 750,000 miles on the original motor but I don't know that letting it idle for thirty minutes (certainly not an air cooled motor) is that beneficial. But then again that was before diesel was $7 a gallon here in the Kommiefornia.
I have found that the FJ engine is not 'warmed up' just by taking the carbs off choke.
The engine oil takes a few minutes longer to get up to proper operating temp.
I believe the oil temp gauge is more critical than oil pressure.
I like to see my oil near the 180* zone before I unleash the kookaloo ponies.
Oil has reached all the places it needs to be once it has pressure (hence the pressure) and that's almost the instant you start it, on a carburetted engine maybe even before it fires and the splash feed as soon as it's spinning.
There is nothing to be gained from leaving a cold engine idling once it's started, it just slows down the warming process. Some will even argue that splash feed at idle speed with thick oil is compromised.
An engine warms up fastest under load and is best to driven/ridden as soon as it starts, avoiding high revs and rapid acceleration until the oil is up to temp, this takes longer than most folks realise, approx 15-20 mins. Remember, if your oil's not up to temp, neither are all the internal bits.
I even upgraded my oil cooler to one with a thermostat (or so I thought) solely in the pursuit of faster warm up.
Noel
"An engine warms up fastest under load and is best to driven/ridden as soon as it starts" ? ...I do wish i was in a warmer climate year round too..but when that big chunk of aluminum (head) is cold..it won't do much for fuel atomization. Some warm is essential in cooler climates,imho.
I'm with Noel on this one. Even in winter temperatures I can start riding with a little choke. Once I get on the main road I push it all the way in, so I don't forget. It runs crappy for a bit but warms up pretty quickly. Obviously no kookaloo until it's warm.
No argument that oil warms up quicker under load, but the question then becomes does this increase wear? As Noel mentioned there is definitely oil pressure, so much so in fact, the oil pressure is much higher than when the oil becomes warmed up. Is this a sign that the resistance of the cold oil isn't getting into the tighter clearances of the engine bearings, cam journals, etc.? Does the thicker oil spread out and cover surfaces from the splash feed to lube the cylinder walls, as well as warm oil would?
While I agree warming up is expedited being under load, I can't help but question does it cause some sort of extra wear and tear on the internals. On the other hand with the invention of split weight oils, fuel injection (think cylinder washdown from all the poorly tuned carbs), and improved manufacturing processes; cars getting 300,000 miles+ (even newer bikes and some iron willed FJ riders getting 100,000+) is the norm. Is sitting there idling and wasting MPGs even worth the extra life you may obtain from doing so. And who to say how much extra life, if any you would get from sitting there warming up for extended periods.
Does it hurt to let the bike warmup before riding? Definitely not, except on the pocket book, watching the dollars burning away and not riding and enjoying quicker. But one thing is certain, as Noel pointed out, revving high/ riding hard on a cold engine with cold oil is a surefire way to decrease the life of an engine.
I personally do not sit there and idle, unless, it's 110f range then I hit that remote start button on the fob and let that puppy cool down before hopping in. But under everyday riding/driving I start it up, let everything cycle for 45 seconds to a minute while I put my gloves and gear on/ seat belt and bluetooth hooked up to the car, and then I head on out with out ringing it's neck too hard before warmed up.
Totally with you on that Robert ????
I was told that you should always let an engine get up to proper operating temperature (where expansion has occurred everywhere and tolerance are as close as they can get to where they should be) before giving the engine any high rpm riding/driving.
Quote from: RPM - Robert on October 04, 2022, 11:44:24 AM
.....I can't help but question does it cause some sort of extra wear and tear on the internals....
Good question Robert but fortunately for us we don't have to speculate on it, what I said was not my own opinion but the finding of people way more qualified than us using facilities we don't have.
The notion that leaving a cold engine idling being more harmful than riding it using the throttle sparingly until up to temp has been acknowledged since well before my time and is what is taught in trade training institutions.
I'm confident that information like this, that is difficult to validate in the field, is well vetted before being included in such courses.
This whole discussion, while interesting, is largely academic anyway, I doubt anyone here will ever put enough miles on their bike for it to matter, with so many other factors that can shorten engine life this one barely rates.
The point I was making was not so much whether it does harm or not, but that leaving your bike idling to warm up is not necessary, recommended or beneficial. I doubt anyone would argue that nearly all engine wear occurs on a cold start, one of the worst things you can do to you bike is have a low cold start/miles ridden ratio.
Start it ride it.
Noel
Quote from: ribbert on October 06, 2022, 07:26:59 AM
Quote from: RPM - Robert on October 04, 2022, 11:44:24 AM
.....I can't help but question does it cause some sort of extra wear and tear on the internals....
This whole discussion, while interesting, is largely academic anyway, I doubt anyone here will ever put enough miles on their bike for it to matter, with so many other factors that can shorten engine life this one barely rates.
Noel
Indeed, the only other thing I would add is, if you are making short trips where the engine would not get up to temperature, you should ride a bit longer. You can also cause damage from the condensation build up in the oil. I have seen this personally only on one vehicle and it was when I was in high school working at an oil change spot. It was a new car with less the 10,000 miles. The person would make short trips of 5 minutes or less to work every day (don't ask me why they didn't walk or ride a bike living that close) When I pulled the drain plug nothing came out. I poke a screwdriver gently into the hole and a bunch of milky mess came out. When we cut the oil filter open it was completely clogged with oily water as well. The engine never got hot enough to evaporate the water and just created condensation time and time again until there was a nice frothy milkshake in the engine. Watery oil doesn't lube as well as non watery oil.
I tend to agree here, Noel. I don't excessively idle my vehicles, unless getting them cooled down before I get in. Even in the winter I have a timer and a space heater that I use that defrosts the inside of the car on the mornings I work and I get in let it idle while strapping in and head on my way.
There are a few who have braved the several hundred thousand mile marker on their FJ but those are definitely the outliers. :hi:
Quote from: RPM - Robert on October 06, 2022, 03:34:01 PM
There are a few who have braved the several hundred thousand mile marker on their FJ but those are definitely the outliers. :hi:
I always knew Noel was an outlier :sarcastic: :sarcastic: :sarcastic:
Yup, I think Noel is up there in mileage, FJLee is one, Mike Ramos another. Fred Greenlee & Capt Ron put some decent mileage on too.
Noel's might see the most all around riding. Touring in the dirt etc and from the pictures I have seen his bike is always very clean and polished.
My morning commute is usually around 25-minutes to get to work.
On the mornings that I take the FJ, my startup routine typically looks like this:
Back the FJ out of the garage.
Close the garage door, put my helmet and gloves on.
Mount the bike, switch it on and pull the choke knob "ON" a couple clicks.
Fire up the bike and while it's idling I back down the driveway and into the street.
Click it into gear and ride off through the neighborhood. (about a 1/4 mile to get out of the neighborhood)
Once I turn onto the main street, I push in the choke-knob and will not need it again, as the bike will idle without choke at stoplights.
It takes a long time for the engine oil to warm up to what I would consider "normal operating temperature" (at least 180 degrees F)
Typically after about 25-minutes of riding a mix of stop/go, 45mph speeds with a stretch of 60mph for a few miles I reach my workplace. The oil temperature is just then reaching around 180 degrees about the time I am pulling into the parking-lot at work.
I never wait for any kind of warmup period before riding/driving off in any of my vehicles, and have done enough research on the subject to know it is not required or beneficial to do so.
My FJ currently has 163,000 miles on it, and still runs as good as new.
Both of my cage vehicles each have well over 200,000 miles on them and run perfectly. I usually just start them and drive off immediately (not driving them hard or revving excessively of course)
Oil pressures in both of those are as they were when new. Do not have an oil pressure gauge on the FJ, just temperature.
Quote from: aviationfred on September 23, 2022, 10:01:40 PM
I actually have an Oil Pressure sensor on Casper. I installed the sensor in the Oil galley port on the left side of the engine, just below the ignition cover.
On a cool morning start up with full choke, it will read upwards of 80psi. Once warm and choke off, it will read about 55psi while riding at 70mph. At idle it will drop down to about 5psi.
1st photo shows the sensor location,
2nd photo shows PSI at a cold start idle
3rd photo shows PSI warm at idle
Fred
What we discussed today!
Thanks for stopping by