It is a brand new motor, and may take a bit to burn the stuff off from the build
Builds Cummins R2.8 H151 Swap into 1993 FZJ80 (4 Viewers)
- Thread starter PurpleFJ62
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- #362
Yea, I have never had a brand new engine before.
When I get the cooling system done I will run it hard for a half hour or so and get it up to temp, then we will see where things stand.
Seriously man great build, loved the creativity
I know we spoke about this on the phone, but just to open up the dialogue to others who could chime in. My thoughts are that the mass airflow sensor could be the problem with the rough running. I recall the diameter of the tube you fit the sensor into being different than the factory supplied tube.
That style of mass airflow sensor is really more like a velocity sensor. As we know from Bernoulli's principle, if you decrease the diameter of that tube, the velocity will increase. Since that sensor is calibrated to the supplied tube size from the factory, then it will be telling the computer the incorrect mass flow of air being supplied to the engine.
You mentioned something about recalibrating it. If that doesn't work, my hunch would be flow separation across the sensor, but since you're nozzling the flow, I don't expect that to occur. Hopefully that sensor doesn't require a fully developed boundary layer, but perhaps recalibration would take care of that.
My question to the community is, what does the mass airflow sensor even do on a diesel? On a spark-ignited engine, it is required to know the mass of air entering the engine to determine how much fuel to inject, as we have to operate somewhere close to stoichiometric ratio. But this isn't true on a diesel. The amount of fuel and the timing at which it's injected determines how much power it makes; a diesel consumes about the same amount of air at a given RPM. What the hell is that thing used for anyway? Injection timing?
I have done a bunch of these and this is the best way we used the stock mounts in most places and one custom one
No trying to hijack this but here is one a buddy made up, to run a NV4500, he has the plans for a toyota adapter, but said he does not want to make it
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- #367
I like the adapter plate, where is this work being done? How was the reverse engineering done? Did you guys use a CMM or 3D scanner?
That exhaust system looks good. Did you keep the crankshaft center line in the same place with the 6BT swap? I could have squeezed the exhaust inside the frame rail but I figured I would take the original route, not sure why I did that.
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- #368
I completed another piece of the exhaust system tonight, what a PITA. I used the same muffler as these people use...
I have tried to continue the spirit of used well gusseted supports at each oem support point.
I wonder what it will sound like now??
I have tried to continue the spirit of used well gusseted supports at each oem support point.
I wonder what it will sound like now??
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- #369
Cummins provides a way to re-calibrate the MAF sensor for exactly this purpose, for people who are too stubborn to use their little aluminum intake tube and cone filter setup. It does require a complete cooling system so after that is done I can try the recal process.
Yesterday I took the sensor out of the MAF housing and changed its height with my hand while the engine was running, I could get the problem in the video to go away.
We shall soon find out. Bernoulli was a bad ass wasn't he!!
Reverse engineer by measurements no CMM or 3D scanner just the old fashion way .
The exhaust, has plenty of room, as you can see the crank shaft is centered the same as a stock motor so we can use stock motor and tranny mounts and keep locations of cross member stock, I plan on doing a strait 4" exhaust no muffler
Is the diameter of your mass flow housing smaller than the factory supplied one? Its possible you moved it into a slower part of the boundary layer, something closer to what it was calibrated for.
What is the MAF for anyway? Does the Cummins documentation say anything about that?
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- #372
Exhaust is done. What a job it was and honestly if you value your free time at all it was not worth doing it yourself. I estimate that just in materials I spent about 700 dollars. It fits quite well and does not contact the chassis even under significant force inputs from my arms.
Most of the parts came from StainlessBros and I really liked the quality, nicest mandrel bends I have seen to date, and they are brushed. If I dont cut or grind them I have a hard time finding the joint to weld, they fit together that good. With the pie cuts I can easily see where to weld because of the discontinuous tangent.
It fits up tight against the floor and goes under all the heat shields just as the stock one did. If I could have gotten mine apart without cutting I would have reused it, there is no way I can justify the amount of time invested in this fancy tube.
Instead of welding round stock the exhaust like most do I made these little pieces to hold the pipe like a hand would. They get spot welded in about a dozen places and were designed to hook up to 1.5'' wide 1/8'' thick strap stock. Gives a nice way to tie into common material and avoids having to notch the end of strap, also increases welding area, I am not expecting a failure in this area.
I am hoping to not crawl under my rig for a few days, I need to power wash my back to get all the grease off my skin.
Most of the parts came from StainlessBros and I really liked the quality, nicest mandrel bends I have seen to date, and they are brushed. If I dont cut or grind them I have a hard time finding the joint to weld, they fit together that good. With the pie cuts I can easily see where to weld because of the discontinuous tangent.
It fits up tight against the floor and goes under all the heat shields just as the stock one did. If I could have gotten mine apart without cutting I would have reused it, there is no way I can justify the amount of time invested in this fancy tube.
Instead of welding round stock the exhaust like most do I made these little pieces to hold the pipe like a hand would. They get spot welded in about a dozen places and were designed to hook up to 1.5'' wide 1/8'' thick strap stock. Gives a nice way to tie into common material and avoids having to notch the end of strap, also increases welding area, I am not expecting a failure in this area.
I am hoping to not crawl under my rig for a few days, I need to power wash my back to get all the grease off my skin.
- Thread starter
- #373
I suspect it is used to calculate the EGR mixing flow rate, however I did not read that in the manual. Engine also has an air intake throttle so it has even more control than engines of a previous generation. All this crap so our costalcrats can breath easily...
I think so the PCM would know how much the EGR was recirculating into the engine. And I believe it also works on some diesels in conjunction with the fueling to keep smoke down before the boost kicks in.
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- #375
Question for the gurus...
Has anyone ever seen the tach needle dip when the turn signal is first switched on or when the reverse lights illuminate?
It is only a temporary dip at the needle, it quickly gets back to its original position.
I had a problem just like this on a 1992 toyota pickup but it was the speedo that would drop to zero mph for a moment, turned out to be some stupid relay under the dash that was a huge PITA to change.
Should I post a video of this?
Has anyone ever seen the tach needle dip when the turn signal is first switched on or when the reverse lights illuminate?
It is only a temporary dip at the needle, it quickly gets back to its original position.
I had a problem just like this on a 1992 toyota pickup but it was the speedo that would drop to zero mph for a moment, turned out to be some stupid relay under the dash that was a huge PITA to change.
Should I post a video of this?
Rivman1243
SILVER Star
My volt gauge dips with the blinker but that's it. Wish I could help out more
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- #377
Does anyone know about the noise filter that is in the tachometer circuit?
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- #378
I fixed the problem of the tach needle dipping. I really need to get it together. Problem was line loss coming out of the Dakota Digital converter box. I ran the tach wire in the harness under the hood over to where the old igniter was, it was like 12 feet of wire.
Redesigned the system and it works great.
Here is a video of the problem. This is with the reverse lights turned on as well, it makes the problem much worse.
Here I hook my 24 valve to it so the system would have a functioning alternator, just curious what would happen.
Redesigned the system and it works great.
Here is a video of the problem. This is with the reverse lights turned on as well, it makes the problem much worse.
Here I hook my 24 valve to it so the system would have a functioning alternator, just curious what would happen.
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- #379
This crappy video shows what happens when I remove the 12' lead to the tach and replace it with a 2' lead. I moved the DSL1-E unit to the LHS kick panel area so the tach lead is about 2'-3' instead of 12', should be good to go now.
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- #380
I got a request for an engine bay shot
