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KROMETOES
09-08-2003, 12:17 PM
A few notes regarding gas to diesel engine conversion of a 1986 F-350 CrewCab Centurion Conversion (the one with the Bronco rear body grafted on). ?I recently bought it and it has a brand new 460 gas engine, never turned over which was installed in 1996 but never completed due to the owners untimely demise. I am removing the 460 and putting a 6.9/7.3 Diesel into it due to personal preferance - I like em..
I bought another complete truck for this, also a 1986 - F-250 Extended cab Ford with a strong 6.9 and a bit of rust about the body. Similar drive trains - both are two wheel drive and autos.
I have done this before (gas to diesel) and I swore I would never do it again but here I am... ? http://www.fourdoorbronco.com/temp/iB_html/non-cgi/emoticons/smile.gif
I have a digital camera and I am taking numerous pictures of every step of the way and of anything that I feel will be of importance (like the one long screw on the lower corner of each headlight bezel).

What I find needs to be done is this, in about this order:

1. Pull off the front bumper, grill, radiator, ac & tranny coolers from both vehicles. Put aside.
2. Remove the front radiator support member complete with headlights that all that grill, radiator and coolers are attached to (actually not as hard as it seems on the 1986!). Put aside.
3. With the front ends wide open, pull the engines and trannys straight through and out. Much easier than pulling it up and over I found, and you don't have to pull the hood off! You can leave them hooked up but you might want to separate them upon installation ( I keep them together). This is the time to do a good pressure washing and painting of the engine and tranny if you want. Makes it much cleaner on installation if nothing else.
4. Remove driver side battery and mounting brackets (you might want to transfer the drivers side inner wheel well also, give it a look over). transfer.
5. Remove motor mount frame mounts and transmission cross member and transfer.
6. Remove electrical wiring associated with diesel from donor - this is the glow plug solenoid and associated bracket on the passenger side inner fenderwell top - transfer.
7. Remove the instrument panel from donor - the "glow plug indicator" the "water in fuel indicator" etc, along with associated wiring. Transfer
8. drain both fuel tanks, yes the fuel tanks will work interchangeably! Use an air hose and put a small amount of air pressure into the return line which will push a majority of the fuel out through the regular line. For the purist, remove the fuel tanks, drain, steam clean, and re-install. For the rest of us including me, cross your fingers and hope all the gasoline is out! While you are at it, remove the 460 vacuum lines and hardware, including the epa canisters etc. Deep six them or sell on ebay unless you are putting the donor truck back together.
9. This is the time to clean the engine compartment. Pressure Wash!
10. Paint the engine compartment, install heat shielding/sound deadening material etc. Also you will need to transfer the entire vacuum system from the donor diesel, this is a good time, after painting.
11. Transfer the exhaust system at this time making use of the available gaping hole, it is much easier to do now.
12. New shocks? Now is the time, and those coil springs might need to be transferred around, the diesel is heavier than the 460 and they are a bit beefier in most cases. In my current case, going from a F-250 into an F-350 I will opt for air adjustable coil spring helpers.
13. Same thing if you need front end parts, why not now?
14. New front axle? Now is the time.
15. Anything else troubling you like master cylinder, heater core, special wiring. Good time to do it. Also make sure that you have a good donor engine, pop them heads off and take a look at it, you have come a long way already and don't want to redo stuff. Good time for a valve job and rings at the least, full rebuild if you have the bucks.

Putting it all together

Now that three months have passed and your wife has left because of the mess in the yard, the neighborhood association has left a dead horse head in your bed etc..

Go online, find a good French recipe for "Horse head aLa rue"

1. Make sure that you have transferred all the above mentioned items. the motor mounts and transmission linkage, electrical components etc. Review the disassembly photos if you have them.
2. Pop that donor engine and tranny into that gaping hole. See how the room that you have been marveling on suddenly vanishes? Make sure your heads and manifolds are on and everything is torqued before you do this, no need to be doing this after it is in the hole!
3. Hook up the exhaust, electrics, fuel line, tranny lines, throttle & cruse control etc. Go ahead, put some diesel into it (prime that fuel filter!) and give it a fire over, but be careful of that fan if it is still on (remember the wrong hand threads on that thing). Make sure that it runs. Cuss when the transmission fluid starts running out on your floor because you didn't do a temp. hose between the tranny cooler fittings.
4. Fix whatever is keeping the thing from starting.
5. Repeat steps 3 & 4 until it works.
6. Re-install any and all engine front drive components such as power steering, alternator, fan, vacuum pump, drive belts etc. Make sure that all vacuum lines are in order. So much easier than after the radiator support is put back on! (why don't they make a front radiator support bracket that swings out on a ford?)
7. Clean and paint the front radiator support member and install it, complete with headlights. Hook up electrics. Try those lights, make sure they work now!
8. Install tranny cooler, ac condenser, horn, radiator, fan shroud, upper and lower radiator hoses (go ahead, spring for the new hoses, you can keep the old ones on a shelf in the garage). Reattach the heater hoses. Reattach the AC hoses., charge system. Start engine again, give everything a once over for leaks, including radiator lines, power steering lines, fuel lines, & heater connections.
9. Reassess the situation, look at all the disassembly photos. Cuss, go back and put on something that you forgot to do when it would have been easier.
10. Go underneath and cuss because the driveshaft won't fit. Take the driveshaft to the proper place with the right dimensions and have them lengthen/shorten it and balance it. For a temporary emergency fix, you can cut it apart, lay it all into a big piece of angle iron, add the necessary driveshft tubing and tack weld it all around, and then do a good bead around. The angle iron will keep it pretty straight (just use it as a guide, dont' weld the driveshaft to it!), but you will need very clean & square cuts to begin with and make dang sure that your yokes are aligned! If you don't know what this means, then take this mess to the odd "type a personality" driveshaft people and have them do it right. Matter of fact, if you know what this means, you will take it to the anal retentive driveshaft people anyway, so just take it to the obsessive and compulsive driveshaft people in the first place and pay them for being type "a" anal retentive obsessive compulsive personality people who know how to make driveshafts right. Forgive them in your mind for being obsessive and be grateful that they have a place in this world too, just like you.
11. Install all grill work, bumpers and everything you forgot or that I forgot to mention. Look over your pictures one more time and check for leaks one more time.
12. Test drive and check for leaks.
13. Drive by ex-wife's parent's house. Honk horn.
14. Call tow truck from ex-wife's parent's house because honking horn blew out electrical system.
15. Fix electrical system, and swear that you will never hook up two similar wires just because they look alike. Refer once again to your pictures where you see now very clearly that the one wire goes to the horn, the other goes to the fuel solonoid switch
16. Go on with your life, and share your wonderful experience with another suffering Ford person (I know, this should actually be the "twelfth step" but I just couldn't make it come out right)

It should be noted that the opinions expressed here tonight should be taken with a grain of salt and that consideration of the fact that it is now 01:18 am here in BRANA, Virginia early Monday Morning be given regarding any technical mistakes I have made.

I will eventually get some pictures up on my page at the yahoo group: ?http://photos.groups.yahoo.com/group/centurionconversions/lst?.dir=/1986+CENTURION+CLASSIC+2000&.src=http://www.fourdoorbronco.com/temp/iB_html/non-cgi/emoticons/grinning.gif&.order=&.view=t&.done=http%3a//photos.groups.yahoo.com/group/centurionconversions/lst%3f%26.dir=/%26.src=http://www.fourdoorbronco.com/temp/iB_html/non-cgi/emoticons/grinning.gif%26.view=t


To all other Ford Centurion folks, I feel your pain!

Respectfully,

Tony C.
AKA KROMETOES

Traveler
09-09-2003, 10:59 AM
Cool, lots of people ask me about doing this conversion, and you have all the answers right here.
Take plenty of pics.

So why aren't the fuel tanks interchangeable, can't you just swap the sending unit/ pickup tube assembly?
The Glow plug light panel makes sense, You only need to swap the main panel if you want a tach right?, oh and if you want your fuel gauge to say diesel only.

Step 9 in reassembly gets me every time.

Oh you've had driveshaft trouble also huh.

Excellent write up!
The reassembly instructions get more and more accurate as you get down through them.

KROMETOES
09-10-2003, 05:53 PM
Guess I was unclear, the tanks are interchangeable, thats why I don't pull them out. ?I have read on some newsgroups that the gasoline tank has some type of zinc coating and shouldn't be used for diesel fuel storage because of injector pump problems but I have never run into that situation myself - not to say that it shouldn't be investigated further. ?Sending unit and pickup are similar at least on the 86's but on a previous Ford gas to diesel exchange, I ran into the problem of there not being a return line for the diesel and had to engineer it... ?I remember that ford chassis being an 83 f-350 with a 300 inline chassis, and the diesel engine going into it an 86 econoline 250 (oil cooler and motor mounts from #### on that one). ?

The main thing is to get all the residual gasoline out of the tank. ?I hook my air compressor hose up to the return line and put the feed line into a tank and blow all the gasoline out. ?Then I put two gallons of diesel in and blow that out and do the same thing with reserve tank using the same fuel that is blown out from the main tank and repeat two or three more times. ?Disposal of the waste fuel is always a problem around here, none of the service stations want it in their waste oil tanks due to the problems with lowered flash point and all that. ?Don't want to burn it through any of my diesel engines either. ?Guess I could mix it all together and slowly add a gallon to each full tank and burn it through that way - if it is diluted enough it won't cause serious harm to the injectors or pistons but why take the chance on ten bucks worth of fuel?

If only I heated my house with oil fuel ? http://www.fourdoorbronco.com/temp/iB_html/non-cgi/emoticons/smile.gif

The picture is of the front end prior to when I removed the engine, what a relief to be able to just pull it out forward instead of pulling it up and over!!! ?I had one fall on me one time - didn't hurt me, I am Norwegian but it busted up the various brackets that held different things onto the front of the motor.

Traveler
09-10-2003, 08:32 PM
What are Norwegians made of steel or something? I work with a couple that they think there made of steel, but they are closer to cotton swabs.

I didn't even think the '86 wold not have a fuel pump in the tank, so yeah it would be easy to reuse by just flushing. The fuel tank coating is a new one on me, I had never heard that.

Good pic. that is what my vehicles look like when I bring them home, wow you actually got to take the parts off yourself, cool!

KROMETOES
09-10-2003, 09:45 PM
UFDA!!
Ya ole, it is the swab part that gets the engines dropped on us in the first place, ya!

Trckmagik
03-26-2006, 05:11 AM
Did this ever happen?