1984 Bronco build thread

[StraightSix]

I've never had any problem with filters clogging from cam break in.

Maybe I'm just cheap....

Hi Guys! I think cam break in was a success. between a new mechanical fuel pump and a gas can on the ground in front of the bumper fueling was a non issue. seems like the thermostat worked fine, top hose got hot a few minutes into the run. hot oil pressure at 3000 rpm was around 45-50 psi, hot oil pressure at idle speeds was 15 psi or so which is less than I expected. the AFR read 16.5-18.5 for most of the run but that could be the result of leaky intake or exhaust. A few heat cycles to make sure the manifolds are sealed up right will be necessary before swapping jets. The oil didnt have any water in it and didn't smell like gas.

I did have a few runs of oil down the adapter plate, but I previously had some oil coming out of side covers and may have leaks on the valve cover too. Im not going to get worked up about a main seal/oil pan leak until I have a little more info. I can always re-click the pan bolts after a few heat cycles I suppose.

The road worthiness list is - Install driveshafts, torque two problem xmember nuts down, figure out my fueling issue (pretty sure its a crumbly spongy jumper I found the other day), run a few heat cycles to get manifolds sealed up and then potentially swap jets, set base timing, and then it should be ready for a ring break in drive.

[mat in tn]

Hi Guys! I think cam break in was a success. between a new mechanical fuel pump and a gas can on the ground in front of the bumper fueling was a non issue. seems like the thermostat worked fine, top hose got hot a few minutes into the run. hot oil pressure at 3000 rpm was around 45-50 psi, hot oil pressure at idle speeds was 15 psi or so which is less than I expected. the AFR read 16.5-18.5 for most of the run but that could be the result of leaky intake or exhaust. A few heat cycles to make sure the manifolds are sealed up right will be necessary before swapping jets. The oil didnt have any water in it and didn't smell like gas.

I did have a few runs of oil down the adapter plate, but I previously had some oil coming out of side covers and may have leaks on the valve cover too. Im not going to get worked up about a main seal/oil pan leak until I have a little more info. I can always re-click the pan bolts after a few heat cycles I suppose.

The road worthiness list is - Install driveshafts, torque two problem xmember nuts down, figure out my fueling issue (pretty sure its a crumbly spongy jumper I found the other day), run a few heat cycles to get manifolds sealed up and then potentially swap jets, set base timing, and then it should be ready for a ring break in drive.

I'm not sure that i would be happy at 15 psi. it is enough and 45-50 is certainly enough, but I like oil pressure. it really does depend on how the engine was built and how it is intended to be used.

[StraightSix]

I'm not sure that i would be happy at 15 psi. it is enough and 45-50 is certainly enough, but I like oil pressure. it really does depend on how the engine was built and how it is intended to be used.

Its a 5w30 break in oil too, it very well may make more pressure with something like a 10w30 or 10w40.

[StraightSix]

Its a 5w30 break in oil too, it very well may make more pressure with something like a 10w30 or 10w40.

Well, after a long and often stressful two weeks of drive line installation, engine rework, fitting fighting and fretting, I think its mostly alright.

I retorqued my manifold nuts after the first heat cycle, most turned 1-2 flats before clicking. I fired the engine back up and got the base timing and idle roughly set. It idles at 600, 19inhg, and about 14.5 on the afr.

I got the fuel system patched up (it wouldnt run off the gas tank for cam break in so I swapped on a new pump and pulled suction from a jerry can on the ground). It was a rotted out fuel hose just forward of the rear axle.

I have an odd sound or vibration every now and again, it always scared the daylights out of me.

I still need to fix those x member nuts, install driveshafts,and fashion a hold down solution for my new optima battery before the ring break in drive.

The Frenchtown Flyer has suggested that I not swap jets just yet. Im lean at part throttle with zero load, around 16-17 afr. He suggests I try out a full load WOT pull before jet swaps. The AFR meter does add a whole extra level to tuning.

I made a small but definitive win by finishing wiring in my new amplifier and powering it on for the first time. Even with the cheap speakers it sounds a lot better than before and the bluetooth will make listening much more convenient in todays world. Not a lot of bass response, but its crisp and clear. Between tgat and the new cab seals it should be quiet when I want and Willie Nelson when I dont.

My rear glass motor doesnt seem to have the "stuff" to get the rear glass up against the resistance of my new tailgate window seals. Im not sure if I should be looking into a replacement motor, rewiring with larger conductors all the way back, or something else. Id welcome input. It worked fine before but the seals were basically nonexistent.

[Gary Lewis]

Well, after a long and often stressful two weeks of drive line installation, engine rework, fitting fighting and fretting, I think its mostly alright.

I retorqued my manifold nuts after the first heat cycle, most turned 1-2 flats before clicking. I fired the engine back up and got the base timing and idle roughly set. It idles at 600, 19inhg, and about 14.5 on the afr.

I got the fuel system patched up (it wouldnt run off the gas tank for cam break in so I swapped on a new pump and pulled suction from a jerry can on the ground). It was a rotted out fuel hose just forward of the rear axle.

I have an odd sound or vibration every now and again, it always scared the daylights out of me.

I still need to fix those x member nuts, install driveshafts,and fashion a hold down solution for my new optima battery before the ring break in drive.

The Frenchtown Flyer has suggested that I not swap jets just yet. Im lean at part throttle with zero load, around 16-17 afr. He suggests I try out a full load WOT pull before jet swaps. The AFR meter does add a whole extra level to tuning.

I made a small but definitive win by finishing wiring in my new amplifier and powering it on for the first time. Even with the cheap speakers it sounds a lot better than before and the bluetooth will make listening much more convenient in todays world. Not a lot of bass response, but its crisp and clear. Between tgat and the new cab seals it should be quiet when I want and Willie Nelson when I dont.

My rear glass motor doesnt seem to have the "stuff" to get the rear glass up against the resistance of my new tailgate window seals. Im not sure if I should be looking into a replacement motor, rewiring with larger conductors all the way back, or something else. Id welcome input. It worked fine before but the seals were basically nonexistent.

It sounds like you are making really good progress.

I agree that you want to tune under load. But I think your idle AFR is a bit lean. Try closer to 12 and see if it doesn’t idle as well as tip-in better.

Willie sounds good in a truck. Seems right at home there.

On the rear window, you might try silicone spray on the seals. Should help it crank up easier.

[StraightSix]

It sounds like you are making really good progress.

I agree that you want to tune under load. But I think your idle AFR is a bit lean. Try closer to 12 and see if it doesn’t idle as well as tip-in better.

Willie sounds good in a truck. Seems right at home there.

On the rear window, you might try silicone spray on the seals. Should help it crank up easier.

Thanks Gary! It feels good. the more pieces it was in the more frazzled I felt. having it mostly put together feels really reliving.

I richened up my idle a bit and its now floating around 13-13.5. baby steps.

Ill see if I can find some silicone spray.

I have been having rough running, odd sounds, and just generally sorta worrisome stuff happening. today, I fired it up to run another heat cycle for the manifolds and noticed that it was indeed running rough and occasionally giving a small shake, but I also noticed that the tach was behaving a little oddly and the noise seemed to be coming from the exhaust in a way I hadn't previously realized. I shut it down and swapped in a different DS2 box. when I fired it back up, it was a whole different engine. it runs smooth, no odd noises and no shakes or shudders. it dropped a full 2 points across the board on AFR which I attribute to getting good ignition on all cylinders. perhaps it wasnt even firing consistently before resulting in excess oxygen in the exhaust gasses.

I was pretty worried, but not Im feeling a lot better.

I got those rust welded xmember nuts off today and tapped them. I know this makes them no longer a lock nut. Ill apply loctite when I put them back on. the way I see it, atleast heat will get that off. rusted lock nuts... they nearly stumped me.

assuming I can get to town to pick up a spare good DS2 box and get the xmember nuts retorqued, and hang my drive shafts, I should be able to drive it tomorrow for the first time since July. If all goes well I plan to di a ring break in drive.

any advice on how to perform a ring break in drive? I wish we had hills around here (and we do have some) but most of them are nothing too steep.

for anyone who is following along since the transmission rebuild, she shifts beautifully now.

[Gary Lewis]

Thanks Gary! It feels good. the more pieces it was in the more frazzled I felt. having it mostly put together feels really reliving.

I richened up my idle a bit and its now floating around 13-13.5. baby steps.

Ill see if I can find some silicone spray.

I have been having rough running, odd sounds, and just generally sorta worrisome stuff happening. today, I fired it up to run another heat cycle for the manifolds and noticed that it was indeed running rough and occasionally giving a small shake, but I also noticed that the tach was behaving a little oddly and the noise seemed to be coming from the exhaust in a way I hadn't previously realized. I shut it down and swapped in a different DS2 box. when I fired it back up, it was a whole different engine. it runs smooth, no odd noises and no shakes or shudders. it dropped a full 2 points across the board on AFR which I attribute to getting good ignition on all cylinders. perhaps it wasnt even firing consistently before resulting in excess oxygen in the exhaust gasses.

I was pretty worried, but not Im feeling a lot better.

I got those rust welded xmember nuts off today and tapped them. I know this makes them no longer a lock nut. Ill apply loctite when I put them back on. the way I see it, atleast heat will get that off. rusted lock nuts... they nearly stumped me.

assuming I can get to town to pick up a spare good DS2 box and get the xmember nuts retorqued, and hang my drive shafts, I should be able to drive it tomorrow for the first time since July. If all goes well I plan to di a ring break in drive.

any advice on how to perform a ring break in drive? I wish we had hills around here (and we do have some) but most of them are nothing too steep.

for anyone who is following along since the transmission rebuild, she shifts beautifully now.

Yes, baby steps is the way to do it.

And a bad DS-II box will do that. I had a bad box when I broke the cam in on Big Blue. Wouldn't hardly rev over 2K in neutral, and the tach went wonky at that point. So I kept it running for thirty minutes and then changed out the box - fixed everything.

Plus, it certainly messes up the AFR readings. So disregard all of the previous readings as everything has now changed. But I find that idle AFR needs to be around 12:1 to make the engine easy to start and provide good tip-in.

To break in an engine, inc rings, you need some significant acceleration. Don't lug it, but don't go full throttle in 1st gear. And don't take it too high in RPM.

On Big Blue I used heavy throttle in 3rd and 4th gears when turning between 2K and 4K RPM. And I didn't allow the RPM to stay the same for more than a couple of minutes in the first 100 miles or so.

[StraightSix]

Yes, baby steps is the way to do it.

And a bad DS-II box will do that. I had a bad box when I broke the cam in on Big Blue. Wouldn't hardly rev over 2K in neutral, and the tach went wonky at that point. So I kept it running for thirty minutes and then changed out the box - fixed everything.

Plus, it certainly messes up the AFR readings. So disregard all of the previous readings as everything has now changed. But I find that idle AFR needs to be around 12:1 to make the engine easy to start and provide good tip-in.

To break in an engine, inc rings, you need some significant acceleration. Don't lug it, but don't go full throttle in 1st gear. And don't take it too high in RPM.

On Big Blue I used heavy throttle in 3rd and 4th gears when turning between 2K and 4K RPM. And I didn't allow the RPM to stay the same for more than a couple of minutes in the first 100 miles or so.

Hi! I just took a drive up and down the road. all seems reasonably well with nothing major to report mechanically. Maybe 3 miles.

hot idle AFR - 12.5

In 1st and 2nd, Im not sure you can really put much load on the engine and AFR stays moderate (no more than 16, normally around 15) regardless of throttle position.

any more than 1/2 throttle in 3rd and you get pretty lean, around 17.

any more that 1/3 -1/2 throttle in 4rth and it gets really lean, 17-20 and then the engine cuts out.

any time you pull from 1500ish in 3rd or 4rth its going to run very very lean.

Current - MC2150 1.08 w/ 47F jets. I have 48, 49, and 50s. I think Ill swap jets before the next ride. is there potentially something else wrong? lean out is almost immediate in 3rd and 4rth as soon as the throttle plates open. I can cruise in 4rth and hold 16 - 17 on flat ground so long as Im not accelerating or at more than about 1/3-1/2 throttle.

does anyone know roughly how many jet sizes I should be moving at a time? Ive heard that you should always go atleast 2, but I think that was in reference to Holleys.

[Gary Lewis]

Hi! I just took a drive up and down the road. all seems reasonably well with nothing major to report mechanically. Maybe 3 miles.

hot idle AFR - 12.5

In 1st and 2nd, Im not sure you can really put much load on the engine and AFR stays moderate (no more than 16, normally around 15) regardless of throttle position.

any more than 1/2 throttle in 3rd and you get pretty lean, around 17.

any more that 1/3 -1/2 throttle in 4rth and it gets really lean, 17-20 and then the engine cuts out.

any time you pull from 1500ish in 3rd or 4rth its going to run very very lean.

Current - MC2150 1.08 w/ 47F jets. I have 48, 49, and 50s. I think Ill swap jets before the next ride. is there potentially something else wrong? lean out is almost immediate in 3rd and 4rth as soon as the throttle plates open. I can cruise in 4rth and hold 16 - 17 on flat ground so long as Im not accelerating or at more than about 1/3-1/2 throttle.

does anyone know roughly how many jet sizes I should be moving at a time? Ive heard that you should always go atleast 2, but I think that was in reference to Holleys.

The power valve in that 2150 should open at 6” or so, depending on what one you have, and bring the AFR back to 14ish.

What vacuum readings are you seeing?

[StraightSix]

The power valve in that 2150 should open at 6” or so, depending on what one you have, and bring the AFR back to 14ish.

What vacuum readings are you seeing?

I wish I had a vacuum gage in the cab so I could record that too. then again, I need at least some attention to look at the road with.

I swapped the power valve and went on another spin.

part throttle is still really lean in 3rd and 4rth. past 1/2 throttle both richen up considerably to 14.5 - 16 in 3rd and 15 - 16.5 in 4rth. right when you hit 4rth, if you put the pedal on the floor on level ground you get 18 for a second and then it richens up.

part throttle cruising in 4rth may be fairly lean, like 16.5 - 17. im still running 93. Im tempted to take it on the break in drive.

it fell flat on its face once rolling out of second. Im not sure if Ive lost my touch with a clutch or if the pumpshot isnt doing what I think.

it feels a lot like it did before with one major caveat - I was pushing it hard up hill in 3rd to see what the AFR would read and I didnt notice that I was rolling nearly 4000 rpm! I dont know if it would have free spun that fast before. on the bottom it feels sorta like I remember, on the top it is going to have a lot more breathing room. not to mention that its lean and the ring seat may improve some.

at this point Im inclined to wonder if Im not a little lean on jets, and if I might not need "more power valve". I dont know if those are still made in multiple spring tensions.