Cummins 6bt questions.
 

Hi guys.Im from sunny South Africa.Great site,and ive learned a lot from here.

I bought an old Ford F250 a week or so ago.78 model...4x4.Hang on hang on...before you guys shut the door in my face[laugh] When it was originally built,the 6bt in there was my idea to the original owner.I run 2 big rigs of my own with this little engine's bigger brothers,so naturally im a big Cummins fan.

However,he sourced the engine and details from there is a bit scetchy.I know it came from a small DAF delivery truck,and according to all my googling after that,it was intercooled.

But i dont know what power it produced,and it only runs to 2500 rpm.Which is already scary enough.**** thing runs at 100mph on my GPS at 2000rpm in 6th.

According to DAF,this engine did have the H1C turbo,but hell,it looks different to the ones ive seen on here.The Compressor housing is actually smaller than the turbine housing.And get this...the turbo sits about face.The intake faces the firewall.It also looks like the intake is upside down.Turbo sits very low.

It has the VE pump,which i already tampered with lol.Just the smoke screw,as this thing pulls strong already.Albeit a bit laggy.But there is massive power around 2100 rpm.

I cant find any CPL plates or anything.Where would the engine number be?

Another little question.I do want to see if it has the silencer ring,as this turbo is fairly quiet.It has a low sing to it,not unlike the old big cam 290 855's,but nearly no whistle.But this is going to be quite a job...as it sits facing the firewall.Does the ring come out easily?

I will post pictures of the old van.I dropped the gearbox on Friday as the clutch broke a finger in the pressure plate.Big Isuzu 6 speed box.Was fun.

Thanx for listening,and lets hope i can get the torch lit as i wonder into the dark side.

Welcome! Many of these engines have such intake horns if they come from delivery trucks. There should be a tag on the turbo that says what turbo it is. On the left side of the timing cover should be the engine tag. If it is an H1C, then there is no silencer ring. For the revs, if you want more, you can get a 3200 spring, to make it just a little scarier :D.

The turbo can be turned any which way to suit you. Simply reclock the housings on the center section (turbine side will take some persuasion with a large hammer) to make it fit.

CPL should be on the timing case near the injection pump.

No silencer ring on your turbo. It sounds like it's got a very small compressor anyway, so you will probably need to upgrade it very soon when you turn up the pump.

We have several members here with Cummins engines in their Fords. Good to have you on board. :)

Thanx for the welcome.Got the clutch pack back today,but it was a bit late to start playing.

Will fit tomorrow.Glad i asked about the silencer ring,as that would have been a big DISSAPPOINTED!!!!!if i did all that dismantling to find nothing.

Anyways,i will post pics a bit later ,and i will take some of the install tomorrow.

Hi again guys.After some major slippage and crap,i got the truck going again.Brand new clutch and it was perfect.......untill i turned the fuelscrew.[laugh]

Anyways...turned the clutch up a bit,and it seems to be holding it now.What can i say,i thought you blokes were overeacting.I turned it nearly 2 turns and boost went up from 18psi to 23psi.Not a big difference,but it seems to be holding it better.The whole rev range feels better.

And there is a lot of smoke.And boy,its laggy as ever,but it pulls like a demon up top.

Couple of questions though.Firstly,on the fuelscrew.have any of you counted the number of threads sticking out from the actual nut holding it?Mine had 6 threads sticking out and it is like 4 and a bit now.How far can 1 go with this thing?

Secondly,it will only go to 18psi in 3rd.The other boost is only available if it really gets plastered in 4th.And the boost rises with revs.Only over 2000 will it go to over 20psi.

Thirdly,i turned the smoke screw back a bit from my initial 2 turns,and it was like there was less boost.?????

And finally,as promised,here is the 4t custard slice...
http://img.photobucket.com/albums/v1...s/P1180431.jpg
http://img.photobucket.com/albums/v1...s/P1180428.jpg
http://img.photobucket.com/albums/v1...s/P1180433.jpg
http://img.photobucket.com/albums/v1...s/P1180429.jpg

WOW, that is a clean truck, looks great man, just watch the front axle, i dont know how well those 44's handle the weight.

thats beautiful

Nice truck. Got any under hood shots? My buddy has one with an old gas engine in it and I'm trying to convince him that a hot 12V is the swap he should do.

See if you can scare up a Holset HY-35 turbo, those work really well on a 4BT. You will get much quicker spoolup and lose most of the smoke.If it doesn't want to drop right back to idle, you are on the edge of runaway - back it off 1/2 turn. Until that happens, keep turning until you have enough power. [laugh] Not enough load on the engine in 3rd to get full fuel from the governor. Sounds like you need to install a 3200 RPM governor spring.That would certainly slow response from a laggy turbo.


Truck looks great! [guitar]

I though those trucks came with Dana 60s in front when a 3/4 or 1 ton. My 1/2 ton is sporting a 44. Guess not, cause that def looks like a 44 also.

I have a Cummins print out listing the 4B at 715 lbs., 6BT 915 lbs. wet, not much more than a big block Chevy or Ford, plus the 3/4 ton Dana 44s have thicker axle tubes, 3/8 of an inch minimum 1/2 inch in some. He should be just fine.

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