Tnashua's 4.0 OHV rebuild... | Page 3 | Ford Explorer Forums - Serious Explorations

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Tnashua's 4.0 OHV rebuild...

Fairly certain you have many followers on this thread! We are just being good, quiet students and observing you pave the way. Thanks for the write up! :salute:

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Keep forgetting to ask (perhaps I should call Odessa)- I don't perceive any thread sealant on the two large plugs on the heads- should I pull them & put sealant on them, or do you suppose there is some? What have you guys done when purchasing new heads? I'll have to do some digging to find a hex driver that big...

I haven't had an issue. The machine shop tends to install them, and they have been leak free for me.

Here are a couple more picts of progress / questionable intake mod...





I know- I still haven't gotten the engine back together, but I am already pondering my next upgrade... Seems that there has been a reasonable praise for the Screamin Demon Coil pack, but there have also been been numerous people who claim that there won't be any advantage... Have the verdict ever dropped on this Question?
Secondly- has anyone used the Accel Coil? If so- how does it compare to stock or the screamin demon pack? I am more concerned about complete burn & fuel economy than how many HP it supposedly adds... I've used Accel products on a few of my previous projects (as well as MSD) & have been pleased with the results, but with limited funds- is it a worthwhile upgrade? I just found an Ultrapower coil pack on RockAuto for about $45 that claims 12% more "fire power". They look suspiciously like the Accels... part numbers 140035 & 140036 depending on plug arrangement. Anyone tried these?
Thirdly- Sound out... What are your favorite plugs (including plug gap) and wires? I am not running a power adder (not for a while at least :) )- so I am looking for NA plugs... Thanks guys!
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stick with the stock coil, and the best plugs will be motorcraft.
Don't get fancy on the plugs, it will hurt you.

I run the accel coil.I wouldnt call it a "upgrade" I just happened to need one and think on ebay it was like $70 delivered. .The screaming pack isnt recommended for forced induction, or atleast many have had problems with it.

X2.....Motorcraft for plugs and stock gap

So much for my hopes (at the end of last week) that I'd have the engine finished & installed by the end of this week... :( Hit plenty of snags (especially last night / this morning) & now I am experiencing a bunch of D words (despair, disbelief, disgust, depression...) Looking for some input from you again!
1.) Installed the cam last night & when it was in position it would not turn by hand at all! Pulled it out & reinspected all surfaces- nothing irregular... Tried my best to view all the cam bearings- still nothing irregular (no scratches, burrs, etc). Re lubed the cam & installed it again... if left 3/16-1/4" out (not in all the way) it turns by hand very easily. Once you get it in further it "locks up". Putting the cam gear on it allows you to turn it by hand, but it seems like it takes more effort than it should. Pulled it again to check for damage- none visible either location... Makes a squishy oil moving noise when turning it w/ the cam gear... Do you suppose that it is a form of hydro-lock causing the trouble? Leaving the cam out 1/4" probably exposes the oil hole in the last cam bearing & allows air to move, but when in further the hole is blocked & the combo of air / assembly lube is causing trouble being trapped by the plug at the end of the block? Anyone have this issue before?
2.) Was cleaning my mildly used longer than stock pushrods & perceived that a couple might be bent. Performed the "roll test" after cleaning & only 2 show no perceivable "wobble", 4 of them are very blatant & the other 6 show varying degrees of bend :(
I am sure that these will degrade lift & cause issues with valvetrain harmonics, but what else can I do (short of angering my wife with yet another expensive/unforeseen purchase)? They'd probably serve their purpose for a while (the ends all look great)- I just don't know...
3.) Was skimming my Haynes Manual (hadn't done that for a while- rebuilt numerous engines in the past & am comfortable enough with procedures that I hadn't felt the need since verifying clearances & torque values) to check for info on 2 issues listed above & ran across the wonderful info that the Rod Bolts are tty (torque to yield) just like the Head bolts :( Why did they not come with the rebuild kit, why did I not determine that when ordering parts? I haven't flipped everything around to see if I can replace them with the pistons/rods in place without putting other parts in jeopardy... I assume that you (who've already rebuilt their engines) replaced your bolts. Anyone not? Honestly- I haven't even checked price yet...
4.) When desiring to turn the crank last night to place the piston in cylinder 1 to TDC- I grabbed my new Harmonic Balancer (I had knocked all the packing peanut debris off of it earlier in the day & painted it to ensure long lasting good looks :) )... There was a piece of tape over the small end (presumably to keep it from filling with packing peanuts), so I removed it & grabbed some degreaser to clean it up. I quickly determined that the Balancer had been dropped at some point prior to being shipped to me. The end was dinged & looked terrible. Undeterred (this was before I discovered any of this other info), I grabbed my die grinder & sanding rolls & began carefully removing the deformation. This took a while longer than I hoped, but I finally got it to measure the same all the way around... I re-polished this area w/ 600 & then 1000 grit wet/dry paper & it looked pretty good. It only goes about 3/8" (maybe) onto the crank before exhibiting major resistance. I turned the crank to TDC & decided that I'd deal with it later. I assume that the drop deformed the inside too (hadn't measured because it looked ok visually)... Anyone know how far it should push on before needing to be pressed on?

I am going to temp the head back on (to keep everything condensed) & cover the engine in plastic again... Then finally make myself port match the exhaust manifolds!
If it were your build & you'd already sunk a bunch of money into it trying to do things right & ran into these issues- what would you do?
Run the cam w/out concern? Use the pushrods or order new? A person might be able to have the rocker shaft stands milled (half of the measurement that the pushrods need to be longer) and just use the stock length pushrods that I have (I have new ones), but that might affect how the rockers contact the valves... Would it make a big enough difference to matter? Then I'd have to take the rocker shaft assemblies back apart again (for cleaning, or for the milling procedure itself)... I don't really want to buy another balancer, but if it were dropped (as it clearly has been)- is it still alright to use? Has to be better than the crusty/cracked unit that I removed from the engine... Run the tty bolts hoping for the best (I know- that really shouldn't be an option), or take the engine back apart again to put new bolts in the rods? Aaaaahhg! Why does every project I get into seem to become a nightmare lately? I'd love it for something to go smoothly for once! Going to get to work- let me know your thoughts... Thanks!

"2.) Was cleaning my mildly used longer than stock pushrods & perceived that a couple might be bent. Performed the "roll test" after cleaning & only 2 show no perceivable "wobble", 4 of them are very blatant & the other 6 show varying degrees of bend "

Oh man, Im so sorry. Those were Delta pushrods. Another strike against Delta. Wow. Id never have imagined this.

You sure you have the cam in the right position? Did you put the plate on and spin it? Do you have oil pump installed? If you have it pushed to far back it binds the oil pump should have some resistance even installed properly as its spining the oil pump.

Where those delta pushrods...that is really odd and is almost impossible to bind a pushrod in the ohv.its a non interface motor..only way would be if a rocker locked up but even at that the rocker would explode before the rod bends..ask me how I know :( me personally I would have or go with smith brothers..what cam do you have??

The crank balancer should get hard after about 3/8" especially when it starts to go over the key.which be careful not to press the key out..the pulley bolt is TTY also and DEFINITELY replace that.its a ford item, your have to search on here for part number, I cant find where I wrote it down..I have seen this bolt stretch more than once and especially if you install or remove it more than once..

The rod bolts are tty but many have reused them with no issues..tty bolts are really hard to understand but the length, thread count and tq effects how much they stretch. .I personally haven't heard of any issues with them..BUT arp does make replacement that are sold for the 302..I dont believe ford overs replacement anymore.

head plugs

when my machinist cut my valve seats and guides he installed the plugs for me. He did use thread sealant. I didn't ask what kind but it's orange in color.

And on the pushrods, as JD said, SmithBros are the ones to get. If that's not a possibility I would definitely bend them straight and check for consistent lengths before installing bent ones.

For what its worth, I had used those push rods without ever checking them. They would definitely have been in that 'bent' condition while they were in my motor.

For what its worth, I had used those push rods without ever checking them. They would definitely have been in that 'bent' condition while they were in my motor.

O I believe its a delta strike again...there is no way you bent those in you motor..only way is if a valve hits the piston (which cant happen in a ohv) or if a rocker locked up, but it would destroy the rocker and I know that didnt happen...

Like I've said..there is a reason I dont use or recommend delta at ALL!!:(

Alright- still warring with myself on the rod bolts... Probably ought to take it back apart & do it right, but I haven't checked into $$$...
I'll order a new balancer bolt when I find a moment to look them up...
Really think the cam thing is just oil/air issue- intend to leave it be. JD- I didn't have the plate installed, but had the cam in the correct location...
Since a person should be able to swap the pushrods by pulling the valve covers- I think I'll go ahead & use the Delta rods until I can afford to buy some SmithBros units...
Sounds like the balancer thing is normal- so I intend to go ahead & use it...
I'll try to contact Odessa about the head plugs to be sure that they seal them (though with the other issues these heads had I'm not entirely sure I'll believe them)...
Bought the Motocraft plugs the other day (Expensive!). Probably could've gotten them a little cheaper online, but I try to give my favorite hometown auto parts store business when I can...
Probably should get wires soon- what are your recommendations?!
Got to get re-motivated & get this thing running! No real time for it this weekend (unless plans change).
Anyone want to buy a set of New Pushrods (stock length) that I have from Northern Auto Parts?! $45 shipped (in 48 of the States in the US anyhow)? Think the part number is MPR471 Melling, but the picture they have up doesn't match. The ones they sent me are the press in ball style...

Anyone have part numbers for the rod & harmonic balancer bolts? Someone on eBay has a (used) balancer bolt listed as TU012. I spent at least 30 minutes searching for prices & availability- No Luck! Called my local parts store- no luck! Called the Ford dealer- got bumped around on voicemail system & never got through to anyone (this was all yesterday- I know they are closed today)... Guess I just need to measure all the bolts & go to a specialty fastener company & buy bolts there that match the size/thread. Let me know if you have numbers (and if you know where to get them & how much they cost). Thanks!

6A 340

Looks like E7RY-6A340-B is the full balancer bolt number?!
The ARP bolts list for the small block (5.0) ford & several other applications, but do not list the 4.0... What about the ARP kit for the 2.9L V6- ARP 153-6001?Want to be sure before ordering!
How about plug wires guys?
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Perturbed... Ordered the rod bolts & harmonic balancer bolts on the 16th. Both were expected to arrive by the 21st... Neither will be here until the 25th?! There goes the weekend plans. Did tear into the dash to replace cluster bulbs-as only one was working before... Got the crusty stock exhaust taken off. Both ex. manifolds ported, cleaned up & coated w/ 1300 degree header paint. Wife doesn't want me to cure them in the oven (gee- don't know why ;) ) so I hit them a couple times with my plumbing torch. hopefully that gives them a head start in the cure process! I have never built an engine with a roller cam (I know- I'm behind the times)- does it still need a specific break in procedure (sorry- I haven't had time to search yet)? I figured on putting break in additive in the oil... I've always run the SBC's up to operating temp varying RPM for about 30 minutes before shutting them down. Course I built a stand for them & broke them in outside of the vehicle... I don't intend to retool for the V6 & figure out the wiring- so it will be in the X already. Still not sure what I want to do about exhaust. Probably should pull/clean the O2 sensors after break in?! Probably run the stock converters for break in... Any input you guys?

The cam doesnt need to be broke in but I still like to break in the rings and ever you use to break in motors I would still follow. I dont use any additives but sure it wouldn't hurt, but I do use just plan regular oil for first 500 miles.I change and check the oil filter after break in..

For exhaust thats up to you.I would replace O2 if its old and run high flow cats, NOT GUTTED!!.o and I run pacesetters headers, you can get the painted one cheap and coat them, they come with black shipping paint only.not high heat paint..I personally like them for a modified motor, they fit great and are well made;)

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Looking to buy a radiator asap- so that it arrives about when I get the engine back together- haven't had much time to look! Looking at : on ebay- it is a 2 core (for a V8), but I don't see why it wouldn't work... I intend to install an electric fan... I prefer to use brands that I know- that I trust, but being well over budget & in a hurry- I may not have much choice... Your advise is appreciated!