1generationkid

Hi I was wondering if anyone could tell me what the primary difference is between the 1st generation 12 valve and the 2nd generation. I know that the injection pumps are different, but can a 2nd generation pump be installed on the 1st gen. . Also are the heads the same. I have a 93 D-250 and want to modify so i can use the injection pump, injectors from a 2nd gen. 12 valve. Can i swap the injection pump and, injectors do I need to swap the heads if it is possible or should I start with a 2nd generation engine all together. Any information would be helpful. Also are the transmissions the same mine is an auto, I believe it is a 47R?. Correct me if i'm wrong but it should be the same trans. right.

kelownadiesel

I think the trannys are different.Im pretty sure you would have to change the head and possibly the timing cover to adapt the new pump.I know that within the 1st gens there a differences in the heads from inter/non intercooled ones.Im just going from what Ive heard however

1generationkid

This 93 D-250 is intercooled but I believe the heads are still different from the 2nd generation, i am not sure though. The long blocks should be the same right. So you think if i find a timing cover of a 2nd generation it will bolt up to the 1 gen. block and I can install the inline pump to it. And also change the head to one from a 2nd gen. and it should bolt up with no problems. If the long blocks are the same the coolant passages should match right.
Any help is appreciated
Thanks

wcbcruzer

Differences between 1st gen and 2nd gen 12v:

* Inline Bosch P7100 injector pump for higher injection pressure an more precise timing
o 52 pound pump required stronger and wider gear housing for support
* Fuel lines redesigned for higher injector pump output
* Fuel filter relocated from a head casting to an intake manifold bracket
* Piston rigs moved up - top ring changed from 14 mm to 8 mm from piston top to reduce "dead space" and cut
* Piston pin bore and connecting rod bushing reduced to tighten piston / pin / rod clearance
* To withstand increased load from valve train:
o Camshaft material changed from chilled iron to chilled ductile iron
o Cam lobes widened, lobes machined for finer surface finish
o camshaft tappet faces hardened
* Wastegate added to H1C turbocharger (WH1C), 12 cm turbo housing replaces 18 cm housing
* Filter Minder add to indicate intake restriction
* Catalytic converter added after Jan 1, 1994
* Clutch weight reduced and clutch engagement improved
* larger harmonic balancer used on 175 hp crankshaft
* prop shaft damper added to reduce drive train pulses

1995 engine changes (begins July 1994)

* Holset HX35W wastegated turbocharger replaces the WH1C.

1996 215 HP engine changes (begins July 1995)

* Piston rings lowered so that top ring is 14 mm from piston top
* CA engines rated for 180 HP and use EGR valve

1997 engine changes (begins July 1996)

* OBD-II required on PCM

dieseldemon

change the front gear housing and the fuel lines and the fuel filter and supply lines and a few nick nak items and you will be good to go the head that is on the 93 will work fine

G1625S

Buying a used p-pump engine is the way to go, especially if you can't have the truck down for very long. What kind of #'s are you looking for out of the truck? The VE is an excellent pump that is capable of more power a lot of folks realize

jimmyray2006

you will have to change, (1)injection pump (2)pump gear (3)gear houseing (4)cam gear (5)injector lines (6)injectors, cause the 1st gen. vs. 2nd gen. the nut on the end of injection line is a larger size, i'm not sure but i think you can get an addaptor to go from the larger injector line to the smaller 1st gen. injector. but that will change the length of the injector thereby making your lines have to be adjusted somewhat. that also makes another connection, another place to maybe have a leak. and a few other smaller accessory items that are diff. from 1st gen. vs. 2nd gen. support bracket underneath the pump, throttle linkage, line to engine block from to the p-pump, & the small vaccum line will need to be moved to a diff. location in the head since the p-pump is longer than the rotary pump. pretty simple change out. good luck!

Ronco95

I agree with WCBCRUZER across the board. I do have a January built "95 auto that has a WH1C turbo. My father in law was second owner at 103XXX miles and bought it that way. My point is, just because it should be a certain part does not mean it is.

Learn to ID your parts to be sure!

Ronnie