1984 Bronco build thread

[Gary Lewis]

Update - I pulled #2 intake rocker and push rod. I couldnt see light through the pushrod, so I blew the pushrod and rocker out with 100 psi air. Both were clear after that. I reinstalled them, cranked it up with the valve covers off and watched for about 5 minutes. I never had a drop of oil make it to #2 intake rocker.

At this point Im assuming Im looking at lifter replacement. Seeing as the block is within its last 20k miles without a total rebuild, I dont think Ill replace the cam. I do think Ill follow the cam replacement lubrication and break in guidlines for the new lifters (sealed power th-900 were what I could put my hands on today, 12 for about $50).

At current all of the push rods are out and the side cover is off. I plan to preemptively coat the lifters in penatraring oil and call it quits until tuesday afternoon. Ill be gone all weekend and Im helping my dad with the "displacement on demand delete" for his 2007 suburban 5.3 on monday. Unless I can find the lifter puller tool mentioned in the post linked above, I guess Im doing it the "old fashioned way".

I dont really want to spend $75 for the cheapest lifter bleed down tool on ebay, but absolutely will if need be. Is there a better way to bleed down my new lifters, or will they not require bleed down to check my rocker clearance (plan to soak them overnight) ? The engines at work get a valve lash adjustment with set screws that Ive performed atleast a few hundred times, go figure this one doesnt work that way :/ unless someone knows better I plan to follow the factory service manuals instructions for valve train adjustment.

Gary,

I dont mean to be dismissive of your advice. I really appreciate it and did seriously consider your recommendation. Thank you for your help as always. I couldnt leave that rocker alone. Knowing what I know now, I assume that there isnt much of a choice.

Dave,

I hadnt really been thinking of the lifter as a servicable part, but Ill pull it out first and have a look. Im not sure how Ill know its in "serviceable" condition, but I plan to look. And Ill do some research on your atf trick! I hadnt heard of that before.

All,

Please dont think Im beyond the point of taking recommendations and thank you for reading.

Not getting oil is bad, obviously, so I'm glad you didn't take my advice. You were right to check it out, and your findings prove you have a problem.

But I can't answer your question on the valve lash adjustment other than to say I'd follow the factory service manual's guidance.

[Gary Lewis]

Here's a video link of a guy disassembling the lifters on his 300 CI Ford engine.

Frank - I was wondering if cleaning the lifters might work. The guy on Youtube said he had a tapping sound under load, which seems to be similar.

[Frank Wyatt]

Frank - I was wondering if cleaning the lifters might work. The guy on Youtube said he had a tapping sound under load, which seems to be similar.

I don't think it could hurt and likely would at least make it better. On the other hand though a new set of twelve lifters for that engine and a bottle of assembly lube is not that expensive. One thing to remember is flat tappets aren't truly flat and are slightly concave which can wear down to being convex over time and no amount of cleaning will correct that. Replacement solves that and the issue of no oiling of the rocker arm as well.

[FuzzFace2]

I don't think it could hurt and likely would at least make it better. On the other hand though a new set of twelve lifters for that engine and a bottle of assembly lube is not that expensive. One thing to remember is flat tappets aren't truly flat and are slightly concave which can wear down to being convex over time and no amount of cleaning will correct that. Replacement solves that and the issue of no oiling of the rocker arm as well.

Thats what I was thinking, "cant hurt" to pull the lifter, take it apart and if it still will not let oil pass then you have the new ones to throw in the motor.

As for pulling the lifter(s) if you are careful not to mar them if going to reuse you can use vise grips and carb cleaner. Vice grip to twist and lift it up and carb cleaner to wash off the stuff that will not let it lift out.

Spray and little CC around the lifter and let it work down a little then try and twist & lift. Push it back down and spray and ......

Keep doing it till out. If lucky it was not marked and you can take it apart, clean with CC, little oil going back together and ready to go back in motor.

I thought the rockers get tq to spec and that is it, non-adjustable right?

You have not changed anything like mill the head or deck the block to change what was there from the factory so no need to change push rods to get them back in spec.

Dave ----

[StraightSix]

I don't think it could hurt and likely would at least make it better. On the other hand though a new set of twelve lifters for that engine and a bottle of assembly lube is not that expensive. One thing to remember is flat tappets aren't truly flat and are slightly concave which can wear down to being convex over time and no amount of cleaning will correct that. Replacement solves that and the issue of no oiling of the rocker arm as well.

Thats what I was thinking, "cant hurt" to pull the lifter, take it apart and if it still will not let oil pass then you have the new ones to throw in the motor.

As for pulling the lifter(s) if you are careful not to mar them if going to reuse you can use vise grips and carb cleaner. Vice grip to twist and lift it up and carb cleaner to wash off the stuff that will not let it lift out.

Spray and little CC around the lifter and let it work down a little then try and twist & lift. Push it back down and spray and ......

Keep doing it till out. If lucky it was not marked and you can take it apart, clean with CC, little oil going back together and ready to go back in motor.

I thought the rockers get tq to spec and that is it, non-adjustable right?

You have not changed anything like mill the head or deck the block to change what was there from the factory so no need to change push rods to get them back in spec.

Dave ----

Frank,

Thanks for the advice! Ill be sure to take that lifter apart and see it there is a smoking gun to be found.

All,

I already have the new lifters so I suppose Ill be putting them in. on valve "adjustment" - these rockers are non-adjustable. all you can do is torque the nut to spec. However, my shop manual does describe a procedure for checking the amount of space between the rocker arm and the top of the valve with the lifter bled down fully. As I understand it you compress the lifter with the lifter sitting on the base circle of the cam then check to see if you have between 0.100" and 0.200" worth of clearance. If you dont you are supposed to get new pushrods to make up the gap. assuming that my new lifters have the same dimensions as the old ones, Im sure it doesnt matter here.

when it comes to lubricant for break in - I know I need a break in grease to apply to the bottoms of the lifters during break in, and Im also fairly sure that the castrol non synthetic 10w30 that Im using in the engine is not appropriate for break in. would it be correct to say that I need zinc additives for the engine oil to be used for flat tappet break in? Is there a special product I should be looking at? oil for a diesel? I need to do some reading on this.

hopefully Ill be able to work on getting the old lifters out after work today. I picked up one of the lifter remover slide hammer type tools on amazon for about $17.

Thanks Guys! I hope you all had a great 4rth!

[Gary Lewis]

Frank,

Thanks for the advice! Ill be sure to take that lifter apart and see it there is a smoking gun to be found.

All,

I already have the new lifters so I suppose Ill be putting them in. on valve "adjustment" - these rockers are non-adjustable. all you can do is torque the nut to spec. However, my shop manual does describe a procedure for checking the amount of space between the rocker arm and the top of the valve with the lifter bled down fully. As I understand it you compress the lifter with the lifter sitting on the base circle of the cam then check to see if you have between 0.100" and 0.200" worth of clearance. If you dont you are supposed to get new pushrods to make up the gap. assuming that my new lifters have the same dimensions as the old ones, Im sure it doesnt matter here.

when it comes to lubricant for break in - I know I need a break in grease to apply to the bottoms of the lifters during break in, and Im also fairly sure that the castrol non synthetic 10w30 that Im using in the engine is not appropriate for break in. would it be correct to say that I need zinc additives for the engine oil to be used for flat tappet break in? Is there a special product I should be looking at? oil for a diesel? I need to do some reading on this.

hopefully Ill be able to work on getting the old lifters out after work today. I picked up one of the lifter remover slide hammer type tools on amazon for about $17.

Thanks Guys! I hope you all had a great 4rth!

You need either a break-in oil with high ZDDP or an additive for break-in with gobs of ZDDP. Scotty The Mad Porter, who built my engine, said that I had to use a break-in oil to keep my warranty. So I went with Brad Penn’s break-in oil.

[StraightSix]

You need either a break-in oil with high ZDDP or an additive for break-in with gobs of ZDDP. Scotty The Mad Porter, who built my engine, said that I had to use a break-in oil to keep my warranty. So I went with Brad Penn’s break-in oil.

All,

Ive made good progress and I hope everything is in order.

The old lifters came out easy, it probably took me 15 minutes to get all 12 out. The first 8 came out by me opening a pair of needle nose pliers inside of them then pulling the lifter up. The last 4 came out with the assistance of a CPU magnet. Im not sure how much the carb cleaner helped but I m grateful that it wasn't too difficult. My old lifter cover gasket was toast, so I replaced it. I was able to do it all without pulling out the distributor or taking apart the induction/fuel system which is nice because I should be able to fire the engine up quickly and easily without too much cranking.

I purchased 12 quarts of 30wt Lucas break in oil and an 8 oz tube of lucas assembly lube. I used the majority of the tube of assembly lube on the rods and lifters, but Im sure it was excessive. I did check my rods for straightness by cleaning them off and rolling them against each other.

Anyways, the engine is fully assembled and filled with the Lucas break in oil. I got it all put together last night and decided it would be wise to wait for a new day to crank it and break everything in. As for break in procedure, I am looking for any advice/input but my rough plan is to start the engine, get it up to about 1500 rpm, then slowly vary engine speed from about 1500 to about 3000 rpm in about a 1 minute cycle for a total of about 30 minutes. After that Ill change the oil and filter to a fresh fill of the Lucas break in oil and let it cool down. After 500 miles Ill change the oil and go on about my life I guess. Does anyone have any advice on flat tapped lifter break in?

Thanks! Ill let you guys know how it goes. - John

[Gary Lewis]

All,

Ive made good progress and I hope everything is in order.

The old lifters came out easy, it probably took me 15 minutes to get all 12 out. The first 8 came out by me opening a pair of needle nose pliers inside of them then pulling the lifter up. The last 4 came out with the assistance of a CPU magnet. Im not sure how much the carb cleaner helped but I m grateful that it wasn't too difficult. My old lifter cover gasket was toast, so I replaced it. I was able to do it all without pulling out the distributor or taking apart the induction/fuel system which is nice because I should be able to fire the engine up quickly and easily without too much cranking.

I purchased 12 quarts of 30wt Lucas break in oil and an 8 oz tube of lucas assembly lube. I used the majority of the tube of assembly lube on the rods and lifters, but Im sure it was excessive. I did check my rods for straightness by cleaning them off and rolling them against each other.

Anyways, the engine is fully assembled and filled with the Lucas break in oil. I got it all put together last night and decided it would be wise to wait for a new day to crank it and break everything in. As for break in procedure, I am looking for any advice/input but my rough plan is to start the engine, get it up to about 1500 rpm, then slowly vary engine speed from about 1500 to about 3000 rpm in about a 1 minute cycle for a total of about 30 minutes. After that Ill change the oil and filter to a fresh fill of the Lucas break in oil and let it cool down. After 500 miles Ill change the oil and go on about my life I guess. Does anyone have any advice on flat tapped lifter break in?

Thanks! Ill let you guys know how it goes. - John

That is good progress. And I think your break-in plans are good. I've always heard that 20 minutes is critical, so I aim for 30 just like you are. I think you'll be fine.

[StraightSix]

That is good progress. And I think your break-in plans are good. I've always heard that 20 minutes is critical, so I aim for 30 just like you are. I think you'll be fine.

Welp guys, disaster has struck. Or perhaps thats a bit overdramatic.

Upon starting the engine up yesterday I had a lot of valve noise for about the first 5-10 seconds, then the majority of it went away but there was still at least one valve worth of severe rattling even after nearly 3 minutes at or above 2000 rpm so I shut it down. In hindsight, I shouldn’t have run it even that long but it hardly matters now. I pulled off the valve cover and every rocker except for #2 intake was full of oil. #2 intake was dry. At this point, I assume #2 intake lobe is gone, and was gone when I started this job a week ago. We ran a compression check on #1 and #2, #1 was making about 130-135 psi while #2 made about 100 psi indicating to me that valve lift on #2 intake is significantly low. I really wanted to measure the valves stroke with a dial indicator but that didn’t work out.

My buddy and I disconnected everything but the power steering pump, exhaust bolts, flywheel housing bolts and the engine mounts yesterday evening. We hope to fly the engine out this afternoon. Should I take the hood off for that?

At this point Im trying to decide between two basic plans –

1) Put a new cam (need to select cam and make sure to end up with a steel gear if I don’t have one already), and a new oil pump in the engine, reseal some stuff, engine mounts, maybe a clutch, and put it back together relatively quickly and inexpensively.

2) Move my plans for a 2022 engine build up to now. The cash is sitting in an envelope, my lack of knowledge is really the most important reason I was waiting for next year. I have a lot to learn. My basic build plan is as follows, but remember, Im a self-proclaimed “know nothing”.

- Rebore cylinders, no more than needed for clean up

- “fix up” and balance rotating assembly

- Flat tappet performance cam

- All new bearings everywhere

- Oil pump

- Possibly roller rockers (maybe not needed for my low rpm application??)

- Use a combination of head/block decking and piston selection to achieve the highest compression I can have while safely running 87 octane gasoline

- Port and polish work in the head

- Oversized valves and valve job

- Clutch

My goals for such an engine build would be to produce an engine that makes gobs of torque between idle and 3000 rpm reliably and with at least decent fuel economy in 87 octane. I don’t really care much about power and I don’t care what happens after 3500 rpm at all. With the way I drive it there’s nothing useful to me much past 3000 rpm anyhow. I suspect most of that comes down to head work, cam selection and getting the compression ratio right (and of course the new bearings, oil pump etc).

if I build the engine, it will go back together for the time being with my efi manifolds, the offy C, my 2150 carb and the durraspark 2. Building the engine will pretty much suck my “bronco budget” dry for the next year or so. There is a good chance Ill eventually either go to a larger venturi version of the 2100/2150, a 4 barrel carb such as a holley 390, or even throttle body injection. But for the next year it will be either my carb or one I don’t have to put much cash into.

Perhaps I should rebuild my transfer case if my engine is about to be producing more torque? Im pretty sure a 12V cummins wouldnt hurt my np435, but that np208 very well may be at 280,000 miles. opinions?

I was planning to spend the next year soaking up information about building a long block but it looks like I may need to accelerate that a bit. Ill rely heavily on my engine builder for technical expertise which is a practice that generally makes me nervous. Can anyone recommend a crash course? Maybe a book I should read, etc? that would be greatly appreciated. Im going to speak to the builder today on the way home from work and should make my choice about how to proceed some time today. No matter which way I go I need to figure out the cam. I already looked over the comp cams site and the 252H seems like their best offering for what I want to do but I haven had a chance to look for reviews and write ups on that cam or to research the many other options. Any advice, specific or general, about cams or otherwise, would be greatly appreciated as always. Thanks! -John

 

[Gary Lewis]

Welp guys, disaster has struck. Or perhaps thats a bit overdramatic.

Upon starting the engine up yesterday I had a lot of valve noise for about the first 5-10 seconds, then the majority of it went away but there was still at least one valve worth of severe rattling even after nearly 3 minutes at or above 2000 rpm so I shut it down. In hindsight, I shouldn’t have run it even that long but it hardly matters now. I pulled off the valve cover and every rocker except for #2 intake was full of oil. #2 intake was dry. At this point, I assume #2 intake lobe is gone, and was gone when I started this job a week ago. We ran a compression check on #1 and #2, #1 was making about 130-135 psi while #2 made about 100 psi indicating to me that valve lift on #2 intake is significantly low. I really wanted to measure the valves stroke with a dial indicator but that didn’t work out.

My buddy and I disconnected everything but the power steering pump, exhaust bolts, flywheel housing bolts and the engine mounts yesterday evening. We hope to fly the engine out this afternoon. Should I take the hood off for that?

At this point Im trying to decide between two basic plans –

1) Put a new cam (need to select cam and make sure to end up with a steel gear if I don’t have one already), and a new oil pump in the engine, reseal some stuff, engine mounts, maybe a clutch, and put it back together relatively quickly and inexpensively.

2) Move my plans for a 2022 engine build up to now. The cash is sitting in an envelope, my lack of knowledge is really the most important reason I was waiting for next year. I have a lot to learn. My basic build plan is as follows, but remember, Im a self-proclaimed “know nothing”.

- Rebore cylinders, no more than needed for clean up

- “fix up” and balance rotating assembly

- Flat tappet performance cam

- All new bearings everywhere

- Oil pump

- Possibly roller rockers (maybe not needed for my low rpm application??)

- Use a combination of head/block decking and piston selection to achieve the highest compression I can have while safely running 87 octane gasoline

- Port and polish work in the head

- Oversized valves and valve job

- Clutch

My goals for such an engine build would be to produce an engine that makes gobs of torque between idle and 3000 rpm reliably and with at least decent fuel economy in 87 octane. I don’t really care much about power and I don’t care what happens after 3500 rpm at all. With the way I drive it there’s nothing useful to me much past 3000 rpm anyhow. I suspect most of that comes down to head work, cam selection and getting the compression ratio right (and of course the new bearings, oil pump etc).

if I build the engine, it will go back together for the time being with my efi manifolds, the offy C, my 2150 carb and the durraspark 2. Building the engine will pretty much suck my “bronco budget” dry for the next year or so. There is a good chance Ill eventually either go to a larger venturi version of the 2100/2150, a 4 barrel carb such as a holley 390, or even throttle body injection. But for the next year it will be either my carb or one I don’t have to put much cash into.

Perhaps I should rebuild my transfer case if my engine is about to be producing more torque? Im pretty sure a 12V cummins wouldnt hurt my np435, but that np208 very well may be at 280,000 miles. opinions?

I was planning to spend the next year soaking up information about building a long block but it looks like I may need to accelerate that a bit. Ill rely heavily on my engine builder for technical expertise which is a practice that generally makes me nervous. Can anyone recommend a crash course? Maybe a book I should read, etc? that would be greatly appreciated. Im going to speak to the builder today on the way home from work and should make my choice about how to proceed some time today. No matter which way I go I need to figure out the cam. I already looked over the comp cams site and the 252H seems like their best offering for what I want to do but I haven had a chance to look for reviews and write ups on that cam or to research the many other options. Any advice, specific or general, about cams or otherwise, would be greatly appreciated as always. Thanks! -John

I'm sorry that it didn't work out. That is a bummer! But I think you are right, the cam must be flat. However, I would check before I tore it down or even pulled the cam out.

Getting the engine out is easier with the hood off, but people have done it w/o pulling it. However, the boom on the engine hoist will have to be really close to the engine or it'll hit the hood before the engine clears the crossmember.

As for what to do, I think it is probably time for a new engine. However, I've come to the conclusion that it is better to buy at least a short block, if not a long block from someone that does this routinely. Having said that, I don't know of someone that builds the 300 "routinely". But, when I asked Scotty The Mad Porter about it a couple of years ago he said he does build them.

On the head, I'm not sure that oversized valves are what you want for a low-RPM engine. Certainly you want good valves and seals, but larger valves are usually needed for engines are going to spin pretty high.

And on the compression ratio, there is another variable - quench or squish. If you get the piston-to-head clearance down to less than .040" then that results in the air/fuel mix being swirled in the combustion chamber, which is supposed to reduce the tendency to detonate. So you need someone that knows what he is doing when you pick your engine builder.