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Discussion Starter · #101 ·
Alrighty. I got the fuel system hooked up and drawing from the fuel tanks.

Once that was done, I took my attention and pointed it towards the idle situation. Once again, after the engine warms up, it does the exact same thing in the video above.

What would cause the engine to increase fueling as it gets to temp?
 

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Timing changes due to the KSB heating up. That can change the idle speed.
 

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Discussion Starter · #103 ·
Timing changes due to the KSB heating up. That can change the idle speed.
The only problem with that is that my KSB isn't hooked up. And unless I don't understand how the KSB works, I would assume it advances timing while cold (increasing engine rpm) and it would work its way back down once reaching operating temp.

My situation was the exact opposite: Engine idled cold beautifully, then once it got warm, the engine started to run over 2K rpm (RPM a guess).

I went out yesterday and fired the truck up and it immediately went to 2K RPM. That's a new development.

I am going to fire the truck up a few times over the next few days and see if the situation persists. If it does persist, then I am going to assume that the fuel supply is steady and that I need to reindex the throttle plate again. I think I was battling some inconsistency from my lift pump and trying to draw fuel out of a 1 gallon container.

@Nascarmark might have been right in another thread: Don't mess with the indexing if you don't have to.
 

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There are 2 types of KSB units. One needs power to turn it on and the other needs power to turn it off. If you have the older style wax motor type shown in the 1st photo below, that one has to have power to turn off. Otherwise it will always have the timing advanced. It used a temperature controlled switch that turned on when the coolant reached 160 deg F. The solenoid type is reversed. It has to receive power to turn on and when the temp is high enough the switch turns off the power to it.
 

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Discussion Starter · #106 ·
So just went out there and re indexed the throttle shaft. I'm really surprised at how a little goes a long way. I don't think from idle till wide open throttle it's more than a quarter turn. So it's no wonder this would trip people up big time. I guess it's obvious when you think a out it.

Other than the idle running too low (just a hair), it's behaving normally.
 

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Discussion Starter · #107 ·
Update here: Since my new job, I haven't been able to get much done on the truck. I did install a new 3" straight pipe exhaust system. I welded it up myself from a generic amazon kit. Just cut and weld and all that jazz.

I have been struggling with the fuel system though. I think the return bypass thing is just not going to work. It will run well for about 3 minutes and then choke out like its out of fuel.

I am going to simplify the system and dump a tube into the tank and bypass the fuel pumps. My only issue is that the fuel selector valve on my year F150 simply turns on and off the fuel pumps so that means if I hook up the system with the aforementioned modification, then it will draw from both tanks at the same time. I think a manual valve might be in order.

I need to hook up the turbo compressor to the intake too. I am not sure if I am going to go non-intercooled for the moment or bite the bullet and do the intercooler plumbing. But that's the scuttlebutt.

EDIT: Do we think the stock Ford fuel filter is a restriction for the diesel?
 

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Discussion Starter · #109 ·
Alrighty, I spent some time this weekend pulling the fuel tanks and gutting the fuel pump assemblies. But before that, I got the exhaust plumbed up.

I bought a generic parts kit from Amazon that consisted of a bunch of 3" steel pipes. This kit was about $110.
0619211124_HDR by Paul Abbott, on Flickr

I got a 3" down pipe that I needed to weld a v-band flange on. This was $70 on eBay.
0613211108 by Paul Abbott, on Flickr

0613211108_HDR by Paul Abbott, on Flickr

0613211108a_HDR by Paul Abbott, on Flickr

0613211157_HDR by Paul Abbott, on Flickr

0613211157a_HDR by Paul Abbott, on Flickr

Imagine that, its a straight pipe!
0619211931 by Paul Abbott, on Flickr

For the part that goes up to the down pipe to the straight section, you just cut and weld and make it work. I didn't take any pics, but its pretty straight forward. I am not 100% on the straight pipe, but I figured it would be easy to add a muffler later if I wanted.

Back to the fuel system: After trying the intank fuel pumps, I was struggling with getting enough fuel to keep it running. I decided to just do it the old school way. So I cut up the fuel pumps and installed straight rubber hose where the pickups and returns are.
0626211318_HDR by Paul Abbott, on Flickr

0626211318a_HDR by Paul Abbott, on Flickr

This turned out to not work out so good so I had to pull them back out, cut up the fuel pump assembly a bit more and then secure the hoses with hose clamps. I was getting some air in the fuel system because I initially just jammed the hoses up in there. No pics. I just wanted to get it done.

While there, the fuel sending unit in the rear broke so I took a picture of how the wire goes on the front one. Well, it broke too. So I busted out the soldering iron and fixed it up.
0627211427_HDR by Paul Abbott, on Flickr

I also was struggling with the idea of the switching system so I decided to just bypass the rear tank and just run clear vinyl lines from the front tank to the pump and return line. I wanted to verify that I am not getting air in the lines. I also bypassed the Ford inline fuel filter in case that was a restriction.

After a quick trip to the gas station to fill up the tank, I can confirm that my fuel system is functioning perfectly with just the lift pump doing it's thing. Finally!

Next step is an intercooler system. I am debating on just a generic eBay or Amazon intercooler setup. I am not going to be towing much of anything. Right now, cost is the most important thing. Plus I do have a pyro and boost gauge ready to be installed to keep things monitored.

Thanks for all your guys' help.
 

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The less complicated you make the fuel system the better. Don't need extra inline filters or in tank lift pumps. Those generally cause problems you don't want. If you want more filtering capacity, Cummins offered dual filters on many industrial engines. See photos below. If you need the parts list I can get it.
 

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Discussion Starter · #111 ·
Charlie, thank you for the great info. I did simplify the fuel system and it fires up and ran good until I got the charge air system hooked up, then it struggled to stay running until it warm. And even then, it would cut out like it didn't have enough fuel. If you gave it the pedal hard, it would cut out. Since I have an odd application engine with an odd application fuel pump and an odd application turbo, I think tuning this thing is going to be a bit of a challenge.

I did get a boost gauge and pyrometer hooked up to it and I think that's going to be the key to the diagnostics and tuning of the engine. I went out and drove it after getting the boost and pyro hooked up and I barely saw 800 degrees and 12psi. As stated above, I would have cutting out issues. So I went and turned the fuel pin up 1 turn and got a bit of smoke on acceleration. Boost went up to 15lbs and my EGTs got up to 850 degrees or so. Then I wondered if my cheap Chinese waste gate attached to my cheap Chinese hx30w was limiting my boost. So I just clamped off the waste gate line and went out and tested. This time I got up to 20 psi and 900 degrees. It sounds like it wants to do more but is running out of fuel. I believe I should see about 30 psi and about 1200 degrees under hard load. Does that sound about right?

I had noticed that the fuel pin that came stock with this fuel pump was not like the other ones that I have seen on the web. I don't think turning it would help. So I may go look for a fuel pin tonight since I have a bit of disposable income.

Is there a comprehensive tuning thread out there?
 

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Discussion Starter · #112 ·
Its been a couple of months so I figured I would do an update.

I installed an eBay intercooler setup in the truck and finally have that dialed in. I have had lots of issues, but mostly my own in the making. I had boost leaks because I didn't have the proper turbo outlet pipe for a while. Having hoses pop off due to poor fitment is just a nuisance. I have the proper outlet so its all good now.

I had a fuel issue again. This time a brand new 12v fuel shut off solenoid died while driving up the 5. So I had to pull the plunger out on the side of the freeway and installed the gutted housing back in the pump. This lead to an unintended casualty: Every AC bracket bolt I had snapped off due to the forces required to shut down the engine via stalling the truck. It took me 8 hours and constant breakdowns to get back home from San Juan Capistrano to Oceanside.

I wound up using a ratchet strap, but it broke several times too. This was the final iteration that got me home. You can see some of the intercooler piping in this shot too.
0910211744_HDR by Paul Abbott, on Flickr

I have also installed a straight through type muffler. It just takes the rasp out of it and so it did what I wanted.
0906211754_HDR by Paul Abbott, on Flickr

To feign solenoid problems in the future, I got one of those brass tipped plungers and reinstalled the 24 volt solenoid. She works proper now.

I also had to redo the front main seal which isn't too hard. I have quite a few small oil leaks I need to take care of too. But half the battle is finding where they are at! Anyway, that's where we are at. I think I need to do an oil change and adjust the vales again. It gets a little clacky at a certain point and then it cleans up. I am just not sure what that is about.




No, I didn't leave it like that. I put it in the same way, but under the bed.
 

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Discussion Starter · #114 ·
You are not kidding they don't like to stop running. But working on the bracket and adding 5/16 bolts really seemed to have helped.

Oddly enough, the brass tipped FSS plunger would not shut off the truck. No idea what the issue is there, but with the 24v solenoid hooked up, I was able to reuse the failed 12v FSS plunger and it works great now.
 
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