Builds My R2.8 Cummins FJ40 (RJ40) daily driver build (1 Viewer)

[ArthurFJ]

Have you checked the runout on your pressure plate fingers?
I was having an issue with mine and the first pressure plate had 0.025" runout and the replacement had 0.015", I got a third plate and it was under 0.002" and all my issues went away.
Good luck great looking 40!

I haven't. That's a good point. I'll check that out tonight. Thanks! It would be really nice if I could drive it haha

 

[ArthurFJ]

Ok. I replaced the pressure plate with the one from O'Reilly (Power Torque). The finger sat MUCH more flat than the previous plate.

I'm still getting the noise (video link below) but it goes away when the engine goes above 1200 RPM and when under load so I'm not so concerned anymore.. Unless people on here think its and issue and I shouldn't be driving it?

 

[ibinazbass]

Sounds like noise from the damper springs in the clutch disc to me. I know you talked about that before... Are there other clutch disc options?

 

[orangeyz]

Ok. I replaced the pressure plate with the one from O'Reilly (Power Torque). The finger sat MUCH more flat than the previous plate.

I'm still getting the noise (video link below) but it goes away when the engine goes above 1200 RPM and when under load so I'm not so concerned anymore.. Unless people on here think its and issue and I shouldn't be driving it?

After further review, I lied, my clutch makes exactly the same noise as in that video. Goes away when I press the pedal or over 1000 rpm even just sitting in neutral.
If it turns into something ugly I'll post up here, but for now I'm writing it off as "Things make funny noises when you lug them"

 

[ArthurFJ]

Sounds like noise from the damper springs in the clutch disc to me. I know you talked about that before... Are there other clutch disc options?

Maybe. I talked to South Bend Clutch and they didn't have anything.. But SPEC clutch has stage 1/2 clutches that may be better than that O'Reilly one

 

[ArthurFJ]

After further review, I lied, my clutch makes exactly the same noise as in that video. Goes away when I press the pedal or over 1000 rpm even just sitting in neutral.
If it turns into something ugly I'll post up here, but for now I'm writing it off as "Things make funny noises when you lug them"

Ok thanks! Honestly if it doesn't make that noise while I'm on the road driving I don't really care that much. Just give the car more character

 

[jim land]

My stock high mileage bj42 make the same noise since i own it (2015)
I drive it everyday

 

[Sheck44]

Ok. I replaced the pressure plate with the one from O'Reilly (Power Torque). The finger sat MUCH more flat than the previous plate.

I'm still getting the noise (video link below) but it goes away when the engine goes above 1200 RPM and when under load so I'm not so concerned anymore.. Unless people on here think its and issue and I shouldn't be driving it?

Arthur .... Just watched the video ... Mine makes the same noise !!
Talked to my mechanic and told him the NV4500 with the LS doesn't make that noise and we cannot figure it out !!
Agreed, I just keep the clutch in at the lights

Steve

 

[Salem747]

@ArthurFJ it just gives you that 4BT vibe.

 

[jim land]

I think it could be the throw out bearing rattling caused by the diesel engine shake at idle

 

[FJBen]

Sometimes the H55f crowd has a little bit of that noise as well with the clutch out. I’m pretty convinced it’s the throw out bearing not coming back far enough.
I can sometimes hear a quiet version of this on mine. It’s way quieter. If I push in the clutch (in neutral) then let it out really fast, not quite dump, it will go away. I’m guessing Yours is can’t go back enough from the clutch and it spinning.

 

[ArthurFJ]

I think it could be the throw out bearing rattling caused by the diesel engine shake at idle

I dont know.. I pulled the slave cylinder off and pulled and pushed on the fork. The sound is made regardless of the throwout bearing position. When I pushed it against the fingers I could hear it spi. But it wasn't a "bad" sound at all

 

[Godfather90]

This is a sound caused by the torsional vibration of the 4 cylinder diesel engine. A heavier flywheel will calm it down a bit.

It's the sound of the mechanical backlash of the gear train when unloaded. It is likely to get worse when the gear oil heats up.

Many manufacturers use a dual mass flywheel for this reason. You can probably make it quiet down by leaving the clutch out with engine idleing and push the shifter gently into any gear besides reverse loading up a syncro ring as a test. Don't push too hard or it will grind. This will take the backlash out temporarily.

I wouldn't worry too much about it.

Mike

 

[ArthurFJ]

This is a sound caused by the torsional vibration of the 4 cylinder diesel engine. A heavier flywheel will calm it down a bit.

It's the sound of the mechanical backlash of the gear train when unloaded. It is likely to get worse when the gear oil heats up.

Many manufacturers use a dual mass flywheel for this reason. You can probably make it quiet down by leaving the clutch out with engine idleing and push the shifter gently into any gear besides reverse loading up a syncro ring as a test. Don't push too hard or it will grind. This will take the backlash out temporarily.

I wouldn't worry too much about it.

Mike

Ok thanks Mike. So a different clutch disc might not work I guess?

 

[Godfather90]

Ok thanks Mike. So a different clutch disc might not work I guess?

Lets check to see how it responds to the situation I described.

Fire it up at idle and with your foot off the clutch and the truck stationary (driveshafts cannot be spinning) gently push it into gear (try 4th gear) and increase the force slowly and see if the sound quiets down. Don't jam it in there too hard of the shift collar spring will release and it will grind. just hold it there long enough to determine if the sound goes away.

Let me know!


Mike

 

[orangeyz]

Lets check to see how it responds to the situation I described.

Fire it up at idle and with your foot off the clutch and the truck stationary (driveshafts cannot be spinning) gently push it into gear (try 4th gear) and increase the force slowly and see if the sound quiets down. Don't jam it in there too hard of the shift collar spring will release and it will grind. just hold it there long enough to determine if the sound goes away.

Let me know!


Mike

Mine did what you described

 

[Godfather90]

So you can either have a heavy custom flywheel made, or button it up and enjoy it. Clutch isn't causing this sound.

I had a 50lb flywheel made for mine to avoid this. It still makes some noise of course, but nowhere near what it used to make with a standard gas flywheel. Heavy flywheel makes it nice to drive as well.

If you up the viscosity of your gear oil in the transmission it will quiet it down a little bit, but it will wear you syncro rings faster and shift like crap. It will still be noisy when its hot as well.

I say run it.


Mike

 

[ArthurFJ]

Thanks for everyone's help with the clutch issue. I've buttoned it up and I've decided to just enjoy the sound now that I know it's not damaging anything.

I still have a potential issue with my cooling system. Could anyone tell me what they're running for a cooling? Here's a quick rundown of mine:
- Flex-a-Lite 51160R
- Fleetguard Compleat ES coolant
- 1 L overflow aluminum tank

System overpressured and fluid came out of my radiator cap.. Is this a normal balancing act?

 

[orangeyz]

Deaeration tank:
Water Header Tank, Vertical, 8" H x 4" Dia, without Cap - Pegasus Auto Racing Supplies
Had to cut and weld the mount to make it use existing holes that were on the firewall for something else.

I had never heard of a deaeration tank until this project. I assume that something about this engine causes air bubbles to form inside and that made Cummins think it was important enough to include in the book.

18-22 psi caps on both OE radiator and that tank. If I had two different caps I would run the lower pressure on the deaeration tank.
The cap pressure reliefs (red arrows) both go to a T under the plastic overflow tank and then into the bottom of that.
T and a 1/8" pipe nipple joining the two air outlets on the engine (red circle) into the top of the tank.
The 3/4" hose out of the bottom (blue arrow) of the tank goes to a T at the bottom radiator outlet into the engine.
I don't know what the fan is, bought it 15 years ago for a different Land Cruiser project and then pillaged it for this one. Probably got it from Summit. I haven't actually seen it come on yet.
I haven't had either cap vent on its own yet, but I have pulled the lever on the tank cap and had it blow air into the plastic res and then pull water back when it cools off. I only started driving it a couple of weeks ago and haven't had any hot days yet though.

Both the Murphy gauge and the Dakota Digital read out end up settling at 180 degrees, but the Dakota is about 5 minutes behind the Murphy.

I swear I'll start my own "Built Thread" eventually

 

[bmoonhajjar]

Deaeration tank:
Water Header Tank, Vertical, 8" H x 4" Dia, without Cap - Pegasus Auto Racing Supplies
Had to cut and weld the mount to make it use existing holes that were on the firewall for something else.

I had never heard of a deaeration tank until this project. I assume that something about this engine causes air bubbles to form inside and that made Cummins think it was important enough to include in the book.

18-22 psi caps on both OE radiator and that tank. If I had two different caps I would run the lower pressure on the deaeration tank.
The cap pressure reliefs (red arrows) both go to a T under the plastic overflow tank and then into the bottom of that.
T and a 1/8" pipe nipple joining the two air outlets on the engine (red circle) into the top of the tank.
The 3/4" hose out of the bottom (blue arrow) of the tank goes to a T at the bottom radiator outlet into the engine.
I don't know what the fan is, bought it 15 years ago for a different Land Cruiser project and then pillaged it for this one. Probably got it from Summit. I haven't actually seen it come on yet.
I haven't had either cap vent on its own yet, but I have pulled the lever on the tank cap and had it blow air into the plastic res and then pull water back when it cools off. I only started driving it a couple of weeks ago and haven't had any hot days yet though.

Both the Murphy gauge and the Dakota Digital read out end up settling at 180 degrees, but the Dakota is about 5 minutes behind the Murphy.

I swear I'll start my own "Built Thread" eventually

View attachment 2498453

I wish you would start your own thread. I am several months behind you guys in my R2.8 build and all of this information is priceless.