Ford Truck Engine - Tilted Forum Project Discussion Community

PDOUBLEOP · 02-24-2004, 12:41 PM

I'm looking at buying a 1979 Ford F250. It's 2wd with auto trans. The owner(my father-in-law) says it is has a 351 with a 2-barrel carb. What version of the 351 would it be? 351M, 351C or 351W. What transmission would it be? C6? I'm not normally a Ford man so I need some help. I'm planning on using it to tow a trailer and I'm checking to see if it'll handle it. It has under 60k miles.

Peryn · 02-24-2004, 04:01 PM

Expect it to put out really crappy numbers. My grandfather has a 76 f150 (super-huge cab, and longest bed available) and he claims it has a 360 in it. It has been smogged to all hell. While he used to tow a trailer with it, it barely can get out of its own way. If its anything like his, it probably will tow it, just dont expect it to go fast.

j8ear · 02-24-2004, 08:20 PM

It probably has a 351m and a c-6. Lay the vin on me and I can get you more details.

The M series motors are very stout, especially the 351 which is a 400 ci block only bored to 351.

C-6 is an excellent tranny too...but since Ford puts the same tranny into a new skin depending on the block it is to be mated to...NOT a new bell housing, bone yard replacements might be scarce. Although I have been seeing a good supply of these rigs for the picking lately.

Very torquey, and very robust.

My personal opinion of the 1979 f250 is that it is the best pickup truck EVER MADE. I am partial to the 4x4 with dana 60's front and rear and full time four wheel drive. EXPLORER edition, Absolute BEAST.

Galvanized body AND bed so probably very little rust.

One draw back to the m series blocks from FORD is that they don't make them anymore, didn't make them for very long and after market and upgrade components are very few and far between.

A good place to start to learn more would be a 78-79 Bronco forum, as the M blocks were the exclusive option in these rigs.

I would probably would not pass it up.

-bear

Boo · 02-24-2004, 09:26 PM

It should be a 351M. Nice engine though thirsty. 79 is IMO, the best year Ford had between 1973 and 1997.

I won't own one now as I prefer/require fuel injection.

PDOUBLEOP · 02-25-2004, 04:16 AM

Thanks for the help! I'll try the VIN as soon as I can get it. I was thinking that one of the first things I should do is change the 2-barrel to a 4-barrel. It might help with fuel economy and power. The hard part will probably be finding a reasonably priced intake and carb.

merkerguitars · 02-25-2004, 05:11 AM

Quote:

Originally posted by PDOUBLEOP
one of the first things I should do is change the 2-barrel to a 4-barrel. It might help with fuel economy and power. The hard part will probably be finding a reasonably priced intake and carb.

Well could hurt it or make it better. I would change it too

Whats the point of having a truck if it doesn't have some balls?
At least having a truck like that parts should be easy and it wouldn't be too hard to swap anything to different parts.

PDOUBLEOP · 02-25-2004, 06:31 AM

Do you guys think this truck will handle a 27' fifth wheel camper for fairly short trips? I usually don't go more than 100 miles. I'd think it will be based largely on the gear ratio, but I have no idea what it might be. I'm sure it's totally stock.

Scorps · 02-25-2004, 09:51 AM

Quote:

Originally posted by Peryn
Expect it to put out really crappy numbers. My grandfather has a 76 f150 (super-huge cab, and longest bed available) and he claims it has a 360 in it. It has been smogged to all hell. While he used to tow a trailer with it, it barely can get out of its own way. If its anything like his, it probably will tow it, just dont expect it to go fast.

wow why would you even use that truck to tow.....I use my van and it pulls good....!

PDOUBLEOP · 02-25-2004, 09:56 AM

what kind of van?

Scorps · 02-25-2004, 10:02 AM

Quote:

Originally posted by PDOUBLEOP
what kind of van?

a 1982 full size G-20 Rv style

with a beat up 350(cam is royally fucked)

PDOUBLEOP · 02-25-2004, 10:05 AM

I've actually got a very healthy 350 in my garage that I know would do it.....I couldn't imagine what it would take to put that in it though.

Scorps · 02-25-2004, 10:15 AM

Well you should have seen the trouble they had putting the motor back in to this van....wow what a job!

theguyondacouch · 02-25-2004, 01:35 PM

As has ben said, it has the 351m, It might should a dana 60, not quite sure. either way, it should be doable, unless it has stupid high gears. Too bad it doesn't have the 300 6

j8ear · 02-26-2004, 11:37 AM

You will have no problem with a fifthwheel trailer, unless your towing around multiple vehicles or horses.

An empty camper trailer shouldn't present much of a challenge.

Here's some things to be on the out look for.

Rear springs and shocks need to be fresh and heavy duty.

Front suspension needs to also be dialed in.

Brakes are easy and cheap to replace. Do all four corners, and make sure your brake lines are solid. They deteriorate over the years, and are also relatively cheap to replace.

Parking brake cable is notorios for needing replacement and this is essential for trailoring.

Right under the master cylinder is the steering column....with a u-joint and a rag joint. These begin to loosen over the years, with brake fluid dripping on them and/or lifted suspension/big tires, stressing everything out. This is a PITA to replace and not really that cheap, unless you can find something decent in a junk yard. If you feel any wobble in the steering, replace it. You DO NOT want this busting apart underway.

Definately want brakes, suspension, and steering solid when towing...

This is not your best option for fifth wheel hauling, but with a freshly tuned 351m, decent suspension, clean braking system, tight steering, a light duty fifth wheel will be manageable, under 8000lbs.

Ideal sitch for any fifthwheel is a dually, preferably with a huge diesel.

I've used my 79 bronco (with 351m) to haul another 6000lbs 78 bronco 500 miles through the pocono's a few times. I wished I had a diesel, but I made it through OK.

Oh and unless you want to get 2-5 mpg, stick with the double barrell carb. You'll feel acceleration and top end improvements, maybe even some better torque, but contrast that with fuel efficiency and you'll wish you stuck with stock. You won't be doing a lot of drag racing with a fifth wheel trailor, after all.

best,

-bear

PDOUBLEOP · 02-26-2004, 11:50 AM

The one thing I have to fix before I use it is the brake booster. We thought it was the master cylinder but we replaced it and the pedal still went to the floor. I'm trying to find one now.

j8ear · 02-26-2004, 12:01 PM

after master cylinder replacement you need to completely flush and bleed the hydraulic system.

What you describe does not sound like a brake booster problem.

Is the actuator arm properly engage in the master cylinder?

-bear

Peryn · 02-26-2004, 12:04 PM

i dont have a complete knowledge of the inner workings of a brake booster, but i was under teh impression that if that went out, you would still have manual brakes, just no power assist.

PDOUBLEOP · 02-26-2004, 12:04 PM

Everything seemed attached properly. The pedal goes to the floor but there is no fluid loss. After removing the booster, it looked like it was in rough shape inside. I've never heard of a booster going out so I was surprised. (I got this info from the owner who is a decent shade-tree mechanic)

Peryn · 02-26-2004, 02:05 PM

Hmm... is the pedal mushy, or does it just drop to the floor? Sounds like a lot of air in the system, master cyl wasn't hooked up right, or master cylinder wasn't put back together properly/ is faulty. Could be something else entirely, but a faulty brake booster doesn't seem like a logical diagnosis, to me at least. Did you make sure to bench bleed the master cylinder before you put it back in the car?

j8ear · 02-26-2004, 03:29 PM

One more thing that came to mind with this truck specific to the 79 model year.

This was the first year the ford installed cat's and air pumps, and a bunch of other breathing, circulating, and efficiency reducing gadgets.

Usually a properly tuned engine with an after market high quality cat will pass a smog test, but if not, everything needs to be fixed. Several system's with vacuum lines, belts, and pulleys will likely need replacement.

If you are unsure of the exhaust in any way, replace the cat back, most OEM manifolds I've seen were still intact, it's the crap afterwards that needs replacement. If it still has a stock cat, it needs replacement.

Sometimes the 'good' shade tree mechanic...I count myself in that group, does more harm then good ;-)

I've learned the hard way about several of these projects.

The Ford elimination kit is a popular option, and really improves efficiency, particularly in the MPG measurement. These systems must be eliminated cleanly, effected hoses and valves removed, and open vacuum connections plugged.

The carb is particularly susceptible to things since it has vacumm advance, secondaries, choke, and multiple idle parameters. Must make sure everything has vacuum to them afterwards.

With a new after market cat, and the ford elimination kit. I have passed inspection.

best,

-bear

BoomTruck · 03-01-2004, 06:18 AM

Sounds like a good deal. My dad had a '78 F-250 that he got in '81, and put well over 400,000 miles (of sometimes not so gentle farm use) on it before he sold it. And as far as I kow, it's still going. The 400-C6 combo was hard to beat for reliability.

And my first truck was an early '77 F-250 Hi-Boy. 7.50X17 bias ply tires from the factory on the most evil split-rims ever designed, no power steering, and a 351M- NP435 4-speed. Soon to be the recipient of a 460.

PDOUBLEOP · 03-02-2004, 05:08 AM

Thanks for all the help. I'm going this weekend to check it out. I look into the things you guys suggested.

kazoo · 03-02-2004, 05:34 PM

Don't know where you're located, but the advice about emission equipment elimination can come back to bite you.

In PA, vehicles that don't have to pass a tailpipe or dynamometer test still need to be checked for presence of factory supplied emission equipment.

They don't care if the EGR is blocked with carbon, if the MAP sensor is fried and produces no square waves, or if the CAT has nothing left inside. They have to be there, connected as per factory installation.

The same would hold true for a 2bbl to 4bbl conversion-I'd make sure to use a factory spec quad/manifold if you need to pass inspection scrutiny.

02-24-2004, 12:41 PM	#1 (permalink)
PDOUBLEOP Insane	Ford Truck Engine I'm looking at buying a 1979 Ford F250. It's 2wd with auto trans. The owner(my father-in-law) says it is has a 351 with a 2-barrel carb. What version of the 351 would it be? 351M, 351C or 351W. What transmission would it be? C6? I'm not normally a Ford man so I need some help. I'm planning on using it to tow a trailer and I'm checking to see if it'll handle it. It has under 60k miles. __________________ ef you-you effing ef

02-24-2004, 04:01 PM	#2 (permalink)
Peryn Junkie Location: San Diego, CA.	Expect it to put out really crappy numbers. My grandfather has a 76 f150 (super-huge cab, and longest bed available) and he claims it has a 360 in it. It has been smogged to all hell. While he used to tow a trailer with it, it barely can get out of its own way. If its anything like his, it probably will tow it, just dont expect it to go fast. __________________ Dont cry kid, It's not your fault you suck.

02-24-2004, 08:20 PM	#3 (permalink)
j8ear Gentlemen Farmer Location: Middle of nowhere, Jersey	It probably has a 351m and a c-6. Lay the vin on me and I can get you more details. The M series motors are very stout, especially the 351 which is a 400 ci block only bored to 351. C-6 is an excellent tranny too...but since Ford puts the same tranny into a new skin depending on the block it is to be mated to...NOT a new bell housing, bone yard replacements might be scarce. Although I have been seeing a good supply of these rigs for the picking lately. Very torquey, and very robust. My personal opinion of the 1979 f250 is that it is the best pickup truck EVER MADE. I am partial to the 4x4 with dana 60's front and rear and full time four wheel drive. EXPLORER edition, Absolute BEAST. Galvanized body AND bed so probably very little rust. One draw back to the m series blocks from FORD is that they don't make them anymore, didn't make them for very long and after market and upgrade components are very few and far between. A good place to start to learn more would be a 78-79 Bronco forum, as the M blocks were the exclusive option in these rigs. I would probably would not pass it up. -bear __________________ It's alot easier to ask for forgiveness then it is to ask for permission.

02-24-2004, 09:26 PM	#4 (permalink)
Boo Leave me alone! Location: Alaska, USA	It should be a 351M. Nice engine though thirsty. 79 is IMO, the best year Ford had between 1973 and 1997. I won't own one now as I prefer/require fuel injection. __________________ Back button again, I must be getting old.

02-25-2004, 04:16 AM	#5 (permalink)
PDOUBLEOP Insane	Thanks for the help! I'll try the VIN as soon as I can get it. I was thinking that one of the first things I should do is change the 2-barrel to a 4-barrel. It might help with fuel economy and power. The hard part will probably be finding a reasonably priced intake and carb. __________________ ef you-you effing ef

02-25-2004, 06:31 AM	#7 (permalink)
PDOUBLEOP Insane	Do you guys think this truck will handle a 27' fifth wheel camper for fairly short trips? I usually don't go more than 100 miles. I'd think it will be based largely on the gear ratio, but I have no idea what it might be. I'm sure it's totally stock. __________________ ef you-you effing ef

02-25-2004, 09:56 AM	#9 (permalink)
PDOUBLEOP Insane	what kind of van? __________________ ef you-you effing ef

02-25-2004, 10:05 AM	#11 (permalink)
PDOUBLEOP Insane	I've actually got a very healthy 350 in my garage that I know would do it.....I couldn't imagine what it would take to put that in it though. __________________ ef you-you effing ef

02-25-2004, 10:15 AM	#12 (permalink)
Scorps Lost!! Location: Kingston, Ontario	Well you should have seen the trouble they had putting the motor back in to this van....wow what a job! __________________ A.K.A. PainTrain

02-25-2004, 01:35 PM	#13 (permalink)
theguyondacouch salmon? Location: Outside Providence	As has ben said, it has the 351m, It might should a dana 60, not quite sure. either way, it should be doable, unless it has stupid high gears. Too bad it doesn't have the 300 6 __________________ "Lick my frozen metal ass!"

02-26-2004, 11:37 AM	#14 (permalink)
j8ear Gentlemen Farmer Location: Middle of nowhere, Jersey	You will have no problem with a fifthwheel trailer, unless your towing around multiple vehicles or horses. An empty camper trailer shouldn't present much of a challenge. Here's some things to be on the out look for. Rear springs and shocks need to be fresh and heavy duty. Front suspension needs to also be dialed in. Brakes are easy and cheap to replace. Do all four corners, and make sure your brake lines are solid. They deteriorate over the years, and are also relatively cheap to replace. Parking brake cable is notorios for needing replacement and this is essential for trailoring. Right under the master cylinder is the steering column....with a u-joint and a rag joint. These begin to loosen over the years, with brake fluid dripping on them and/or lifted suspension/big tires, stressing everything out. This is a PITA to replace and not really that cheap, unless you can find something decent in a junk yard. If you feel any wobble in the steering, replace it. You DO NOT want this busting apart underway. Definately want brakes, suspension, and steering solid when towing... This is not your best option for fifth wheel hauling, but with a freshly tuned 351m, decent suspension, clean braking system, tight steering, a light duty fifth wheel will be manageable, under 8000lbs. Ideal sitch for any fifthwheel is a dually, preferably with a huge diesel. I've used my 79 bronco (with 351m) to haul another 6000lbs 78 bronco 500 miles through the pocono's a few times. I wished I had a diesel, but I made it through OK. Oh and unless you want to get 2-5 mpg, stick with the double barrell carb. You'll feel acceleration and top end improvements, maybe even some better torque, but contrast that with fuel efficiency and you'll wish you stuck with stock. You won't be doing a lot of drag racing with a fifth wheel trailor, after all. best, -bear __________________ It's alot easier to ask for forgiveness then it is to ask for permission.

02-26-2004, 11:50 AM	#15 (permalink)
PDOUBLEOP Insane	The one thing I have to fix before I use it is the brake booster. We thought it was the master cylinder but we replaced it and the pedal still went to the floor. I'm trying to find one now. __________________ ef you-you effing ef

02-26-2004, 12:01 PM	#16 (permalink)
j8ear Gentlemen Farmer Location: Middle of nowhere, Jersey	after master cylinder replacement you need to completely flush and bleed the hydraulic system. What you describe does not sound like a brake booster problem. Is the actuator arm properly engage in the master cylinder? -bear __________________ It's alot easier to ask for forgiveness then it is to ask for permission.

02-26-2004, 12:04 PM	#17 (permalink)
Peryn Junkie Location: San Diego, CA.	i dont have a complete knowledge of the inner workings of a brake booster, but i was under teh impression that if that went out, you would still have manual brakes, just no power assist. __________________ Dont cry kid, It's not your fault you suck.

02-26-2004, 12:04 PM	#18 (permalink)
PDOUBLEOP Insane	Everything seemed attached properly. The pedal goes to the floor but there is no fluid loss. After removing the booster, it looked like it was in rough shape inside. I've never heard of a booster going out so I was surprised. (I got this info from the owner who is a decent shade-tree mechanic) __________________ ef you-you effing ef

02-26-2004, 02:05 PM	#19 (permalink)
Peryn Junkie Location: San Diego, CA.	Hmm... is the pedal mushy, or does it just drop to the floor? Sounds like a lot of air in the system, master cyl wasn't hooked up right, or master cylinder wasn't put back together properly/ is faulty. Could be something else entirely, but a faulty brake booster doesn't seem like a logical diagnosis, to me at least. Did you make sure to bench bleed the master cylinder before you put it back in the car? __________________ Dont cry kid, It's not your fault you suck.

02-26-2004, 03:29 PM	#20 (permalink)
j8ear Gentlemen Farmer Location: Middle of nowhere, Jersey	One more thing that came to mind with this truck specific to the 79 model year. This was the first year the ford installed cat's and air pumps, and a bunch of other breathing, circulating, and efficiency reducing gadgets. Usually a properly tuned engine with an after market high quality cat will pass a smog test, but if not, everything needs to be fixed. Several system's with vacuum lines, belts, and pulleys will likely need replacement. If you are unsure of the exhaust in any way, replace the cat back, most OEM manifolds I've seen were still intact, it's the crap afterwards that needs replacement. If it still has a stock cat, it needs replacement. Sometimes the 'good' shade tree mechanic...I count myself in that group, does more harm then good ;-) I've learned the hard way about several of these projects. The Ford elimination kit is a popular option, and really improves efficiency, particularly in the MPG measurement. These systems must be eliminated cleanly, effected hoses and valves removed, and open vacuum connections plugged. The carb is particularly susceptible to things since it has vacumm advance, secondaries, choke, and multiple idle parameters. Must make sure everything has vacuum to them afterwards. With a new after market cat, and the ford elimination kit. I have passed inspection. best, -bear __________________ It's alot easier to ask for forgiveness then it is to ask for permission.

03-01-2004, 06:18 AM	#21 (permalink)
BoomTruck Insane Location: On a gravel road rough enought to knock fillings out of teeth.	Sounds like a good deal. My dad had a '78 F-250 that he got in '81, and put well over 400,000 miles (of sometimes not so gentle farm use) on it before he sold it. And as far as I kow, it's still going. The 400-C6 combo was hard to beat for reliability. And my first truck was an early '77 F-250 Hi-Boy. 7.50X17 bias ply tires from the factory on the most evil split-rims ever designed, no power steering, and a 351M- NP435 4-speed. Soon to be the recipient of a 460. __________________ Judge me all you want, but keep the verdict to yourself. Last edited by BoomTruck; 03-01-2004 at 06:22 AM..

03-02-2004, 05:08 AM	#22 (permalink)
PDOUBLEOP Insane	Thanks for all the help. I'm going this weekend to check it out. I look into the things you guys suggested. __________________ ef you-you effing ef

03-02-2004, 05:34 PM	#23 (permalink)
kazoo Psycho Location: Where the night things are	Don't know where you're located, but the advice about emission equipment elimination can come back to bite you. In PA, vehicles that don't have to pass a tailpipe or dynamometer test still need to be checked for presence of factory supplied emission equipment. They don't care if the EGR is blocked with carbon, if the MAP sensor is fried and produces no square waves, or if the CAT has nothing left inside. They have to be there, connected as per factory installation. The same would hold true for a 2bbl to 4bbl conversion-I'd make sure to use a factory spec quad/manifold if you need to pass inspection scrutiny. __________________ There ain't nothin' more powerful than the odor of mendacity -Big Daddy