how tight can I wind the Ld 465-1C

[bradmachine]

I just brought the M35A2 home a week ago tomorrow....drove 40 mph at 1800 rpm all the way...30 miles.....my son following me said his speedometer read 45....from the posts I have read I get the idea the duece speedometer may read about 10 percent slow.???...is this the general rule..??? anyway...I didn't want to push it with the old oil in it and all.so I stayed at 40 mph...... I changed the oil...put 15w40 in it and then read somewhere that 30 wt is the correct oil....should I change it or run the 15w40.....the oil pressure is just a hair shy of half way on the gage...which is 30lbs...60is max on my gage....the engine is the 1C version mfd in 1986...so my main question is can I run this up to 55 mph, on the interstate..???.. can I wind the engine up to 2400 or so....or am I asking for an explosion under the hood..????...the way I figure it by the rpm...the max speed for this vehicle at 2500 rpm would be about 60 mph.....it has the overdrive transmission I think....the model number of the trans has a 3 in it not a 2.....??????????? so how fast can I drive this vehicle considering the engine to be good..???

 

[Recovry4x4]

The speedo on my tractor is 1 mph slow. Reading 55 the truck is doing 56. The speed was confirmed by GPS and my Radar gun. I've driven the tractor 1200 miles at 55 MPH will no problems. Fuel mileage suffers much over 50. Keep in below 2600 and you should be fine.

 

[clinto]

Speedo on my truck is dead accurate-timed it against my 2003 F-150 today and ran it against one of those trailer mounted radar units on the interstate yesterday.

 

[area52]

I just picked my deuce up this week and drove 800 miles, mostly at 55 MPH. My speedo was about 5-7 miles off according to my chase truck.
It roared along just fine at 2500 rpm.

 

[SasquatchSanta]

Hello,

Kenneth Engle said in is post that at over 50 MPH fuel mileage suffers.

How many RPM are you churning at 50MPH?

If this sounds like a dumb question it's because I have 1400 rubber on my deuce and will soon be running 395s (46.7 tall). I'm trying to determine where the "sweet spot" is.

I assume you're running 1100 super singles. Do you know the diameter of 1100s?

With 395s I'll be turning 2100 @ 55MPH, 2300 @ 60MPH and 2500 @ 65MPH.

Thanks,

 

[houdel]

Bradmachine - to try to answer your questions directly:

1. Per the TMs, max engine speed under load (i.e., when driving) for a LDT465 should not exceed 2600-2650 rpm. Your engine govener should limit rpms to that level, if not, get it adjusted. Exceed those speeds only if you have a very fat wallet! Also, as noted, fuel economy decreases rapidly at higher speeds.

2. Re 15W-40 oil - Don't even worry about it. Multi viscosity oil thinks it is 15 weight when cold and 40 weight when hot. All that means is that the viscosity does not vary with temperature as much as a single weight oil. This is good, as it flows quicker to provide faster lubrication when the engine is cold, and provides superior lubrication when hot. I suspect the vast majority of Deuce owners use 15W-40.

3. Speedos vary a lot. Some read close to dead nuts, mine is 10% low per my GPS. Live with what you got, if yours reads low just figure out what your indicated speed should be to stay within posted speed limits.

4. Is the 30 psi at idle or at road speed? 30 PSI is ok at idle, not so good at road speed. If in doubt, tee in a mechanical gauge for a second opinion. I have read of some trucks having a 60 psi gauge and a 120 psi sender, you might be in that boat.

Ernie - If you want to find the "sweet spot", you need to find specific fuel consumption chart for your engine. It shows fuel consumption vs engine rpm. I have attached one for a LDS465-1 engine, not quite the same animal but pretty close. Interestingly, it shows 175 peak HP, correct for that engine, but max engine speed of only 2600 rpm, I thought the LDS engines were rated for 2900 rpm. Also mentions 2 hole nozzles, I thought they had 1 hole nozzles. As you can see, the lowest specific consumption in that chart was in the 2000 rpm range but pretty flat from 1600-2200 rpm, should be pretty close for the LDT. Maybe Bjorn or Gerhard can find a specific fuel consumption chart for the LDT and post it here for us.

 

[rmgill]

Wow, torque drops off after 2000 RPM.

 

[williamh]

4. Is the 30 psi at idle or at road speed? 30 PSI is ok at idle, not so good at road speed. If in doubt, tee in a mechanical gauge for a second opinion. I have read of some trucks having a 60 psi gauge and a 120 psi sender, you might be in that boat.

i agree 30 at road speed is not a good thing .... i would check the oil with a mechenical gauge first ... and if it is that low ... i would chang the filters and the oil and see if it increases ..hopefullly its that .. if not ,i would drop the pan and start looking for bad bearings as i was changing the oil pump !

oh ya ...

 

[Recovry4x4]

Engineers rule of thumb is 10psi per 1000 RPM. Seems low but will survive.

 

[JasonS]

I think that the rule of thumb is a very loose approximation. Supposedly, wide small diameter bearings require less pressure to maintain an oil film and vice versa for large diameter narrow. More importantly, I think, is whether or not it is low oil pressure due to excessive oil clearances. There was an old app note from one of the bearing manufacturers which showed that as bearing clearances were increased, the length of the oil wedge that the crank rode on decreased. That suggests that you will have less bearing load capability if you have excessive clearances. Probably more likely to have contact between the crank and the bearing.

 

[Westech]

mine runs at 35 psi at 2700 rpm. I have run mine at 2700 rpm and well over 65 mph (new 11:00 tires) for 800 miles at a strech and no problems besides a little slobering from the heads. I have had mine up to 3000 for a short dash befor and it sounds great. The multe fuel is a very solid engine as long as you let it warm up befor you race it and let it idle befor shutting it down after a run,thats the trick. As of oil... well im running 15-40 shell rotella and it holds up well. I do change my oil every 1000 miles or so and filters at every other oil change. I have really trashed that engine and beat the heck out of it and it always starts and moves that truck at brake neck speeds. now... if i could get a good trany i would be very happy!!

 

[bradmachine]

I have never run this over 2000 rpm....I have changed the oil and filters...15w40 rotella...when I picked up the truck I started it and the oil pressure went to 30 and stayed there all the way (30 miles) at 45 mph/1800 rpm......with the old oil...I changed the oil and the pressure seemed to drop slightly...maybe 2psi.....today I ran the engine (after a little warmup) and at about 1500 rpm the needle would hold about 35 but the needle would drop back to 30 and waver a little....?????....I am not sure if I have a poor ground on the gauge, or a bad sender, or low oil pressure....I took the oil pressure regulator off the engine and will test the springs at work tomorrow.. as per the maintenance manual....???????...Maybe 35 psi is enough.....

 

[Westech]

YOUR FINE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! RUN THAT ENGINE!!!!!!!(after you check the springs) but really.... if there was a oiling/engine problem that thing is going to be a 3000 pound bomb and its going to let loose, not just bounce the needle around a bit. RUN IT

 

[bradmachine]

Run It... Aye, Aye...........

 

[Westech]

here is one more note..... I have been a tech (and now i run my shop) for over 12 years. 35 psi in the deuce or even a little lass is ok, or 60 on the 120 psi. if there is a worn beaing your going to hear a knock BAD!! or at idle the oil psi is going to drop to 0. I have seen it a 100 times on jeeps that the thing runs fine but the oil psi drops to 0 at idle. this is caused by worn cam bearings. kinda like this..... knock= rod bearings, loss of oil psi at idle= cam bearings, A screaching sound = main bearings. now this is not 100 % but as close as you can get. that engine is rated to substain 130 HP and 2600 rpm for ever!! RUN IT its the best thing you can do for a diesel. you let them sit or just putt around and your going to mess them up.

 

[bradmachine]

I sure appreciate all the ideas and help from you guys....thanks....William H from SDiego hit the nail on the head.....I tested the springs in the oil pressure regulator and they were in spec....so I put it back together and removed the oil pressure sender and screwed a gage in the side of the block for a direct reading..I looked at the sender and on the side in fine print it said 120 psi....so there it is......and to confirm the situation....at idle the pressure went to 60 psi...at 1000 rpm 70 and at 1500 75 psi....so the pump is working ....the regulator is working....and the gage is reading exactly half....so this engine is good.....and I'm a happy camper.....thanks all ....and now I'm doing some 12 oz curls......now all I need is a muffler........???????????????

 

[SasquatchSanta]

Bradmachine - to try to answer your questions directly:


Ernie - If you want to find the "sweet spot", you need to find specific fuel consumption chart for your engine. It shows fuel consumption vs engine rpm. I have attached one for a LDS465-1 engine, not quite the same animal but pretty close. Interestingly, it shows 175 peak HP, correct for that engine, but max engine speed of only 2600 rpm, I thought the LDS engines were rated for 2900 rpm. Also mentions 2 hole nozzles, I thought they had 1 hole nozzles. As you can see, the lowest specific consumption in that chart was in the 2000 rpm range but pretty flat from 1600-2200 rpm, should be pretty close for the LDT. Maybe Bjorn or Gerhard can find a specific fuel consumption chart for the LDT and post it here for us.

Has anyone got out there got a specific fuel consumption chart for and LDT465 that they could please attach and sumbit?

Ole Santa is trying to get his Sleigh fine tuned.

Thks