4.6 severe "gallop" when cranking

I use a slide ammer. You did remove the bolt?
I did indeed remove the bolt. Pretty tough to use a slide hammer when the tube is sandwiched between the partially-removed head and the exhaust manifold. I suppose I could repeatedly yank the head on the tube and hope it comes out!
 
Look thru my Red Cougar Build thread. But; It's easier to call a local yard, And ask him what kind of romeo blocks he's got cheap, 2v reasonable mileage, "This is a long time customer" :)
Locally, they're 400-2200, depending on condition.
If you can talk your way thru the sale, That's the best you'll get.
If they ask you for a tax number, you are getting a shitty price. :)
 
I have not found any piston or valve damage when inspecting them after removal. I did find some cam journals in the head that looks pretty bad, also one or two cam journals are very bad looking. Since the cams are hard, I'm surprised to see ANY damage to the journals when running in aluminum. I would think that the aluminum would melt before damaging the cam.

I may have put the engine back together with new gaskets and such before I pulled the heads but I'm not going to put it back together now without making it right. I'd like to do a PI head swap but I really don't feel like pulling a set of heads from a donor, IF I can find one.

Also, I'm really not crystal clear about what years and what vehicles fits a 95 Tbird block without modifications so there's that...plus the $$ they would cost...

The only truly unique aspect to the 94-95 block as far as interchange is the timing cover has the aluminum block(aka “Windsor”) pattern vs all 96+ iron blocks where the bolt under the water pump is in a different spot, otherwise all 4.6 heads interchange with it.

Other significant difference is the fifth main cap isn’t cross bolted but I wouldn’t worry about that unless you’re running serious boost
 
Look thru my Red Cougar Build thread. But; It's easier to call a local yard, And ask him what kind of romeo blocks he's got cheap, 2v reasonable mileage, "This is a long time customer" :)
Locally, they're 400-2200, depending on condition.
If you can talk your way thru the sale, That's the best you'll get.
If they ask you for a tax number, you are getting a shitty price. :)
Yeah, that ain't happening...
 
I pulled the remainder of the engine to inspect the bottom end bearings. I mean why not, only 6 bell housing bolts and 2 motor mount bolts left. If i wouldn't have found cam bearing and lobe damage I wouldn't have felt the need but...

I pulled all 5 main caps and two rod caps on different journals. All looked great...and this engine has145K miles on it. I've seen some evidence that this engine has been disassembled at one time. The bearings look so go I would have thought they might be new-ish.

I have never heard this engine run. I'm probably not going to keep this car. I'm torn between doing a complete rebuild or just replacing the oil pump, lash adjusters and cam followers, install a timing set and put it all back together.

OR, I could install another engine I bought from my neighbor that I've never heard run and rebuild the one I just pulled to put in another car. Since the car is a 95, I'm leaning toward putting the old engine back together. The other engine is from a 96 Lincoln (RWD).

I could find nothing damaged and no issues except for the 4 cam followers out of place (2 in each head) and one pretty well mangked cam journal and bearing tower with a couple more with slight damage, all on the passenger side head.. I'm inclined to believe the cam timing was actually OK to begin with. I could even use the old timing components to put it back together providing i can find the different color timing marks on the chains. Not sure if the tensioners can be collapsed and reused.

I'm going to measure cylinders tomorrow before i make a final decision with y'alls help...
 
If the bottom end looks good, I say run it. However there is no way I would put those heads back on! Not only is the valve train suspect, but the 94/95 heads are known for wiping out valve guides and seals. Ideally now would be the time for a PI top end swap, but at the very least I would get a set of 96+ NPI heads. Between Mustang forums, local junkyards, and Facebook, you can probably find a good set for next to nothing from someone who already swapped them out for PIs.
 
If the bottom end looks good, I say run it. However there is no way I would put those heads back on! Not only is the valve train suspect, but the 94/95 heads are known for wiping out valve guides and seals. Ideally now would be the time for a PI top end swap, but at the very least I would get a set of 96+ NPI heads. Between Mustang forums, local junkyards, and Facebook, you can probably find a good set for next to nothing from someone who already swapped them out for PIs.
Yeah, I might be able to swing that, but there are NO MN12s within 150mi of me. So... which Mustang heads would be a direct swap with zero modifications? I'm thinking that the beast doesn't exist from what I remember. Everything from a Mustang needs modification, right? I DO have a set of 96 heads but from what I remember, the cam bearing journals are pretty bad as the engine suffered a coolant dump to the oil pan and was run that way. I have the cams that go with those heads but I would be really wary of using them. I'm sure they would be good for a while but I like to drive the cars I'm going to sell to wring out the bugs and know that they are semi-reliable when I let them go...
 
physically no 2V head needs modification to fit on another. Mustangs aren’t the only source; any Ford that came with the 4.6 or 5.4 SOHC has nearly identical heads that will interchange, be it mustang, Tbird/cougar, Crown Vic/grand marquis/town car and even F series trucks/econolines/98 navigators.

To keep things simple 96+ npi heads are the way to go. Same combustion chamber so same compression ratio/spark curve your car’s programmed for and no other changes needed. The beauty of 96+ npi heads is they actually flow about the same as PIs and will accept PI cams and intake, making them about the equivalent to an actual stock PI motor if you go that route down the road
 
Yeah, I might be able to swing that, but there are NO MN12s within 150mi of me. So... which Mustang heads would be a direct swap with zero modifications? I'm thinking that the beast doesn't exist from what I remember. Everything from a Mustang needs modification, right? I DO have a set of 96 heads but from what I remember, the cam bearing journals are pretty bad as the engine suffered a coolant dump to the oil pan and was run that way. I have the cams that go with those heads but I would be really wary of using them. I'm sure they would be good for a while but I like to drive the cars I'm going to sell to wring out the bugs and know that they are semi-reliable when I let them go...
For a direct bolt-in for your purposes, you want 96+ NPI heads, which were on literally every Ford product with a 2v 4.6 or 5.4 from 96-00, with the exception of the 99/00 Mustang GT. So 96-98 Mustangs, and 96-00 Crown Vic/panther platform cars, 97-00 F150/Expedition/Econoline, as well as 96/97 MN12s. Surely you can find one of those somewhere to grab the heads off of.
 
For a direct bolt-in for your purposes, you want 96+ NPI heads, which were on literally every Ford product with a 2v 4.6 or 5.4 from 96-00, with the exception of the 99/00 Mustang GT. So 96-98 Mustangs, and 96-00 Crown Vic/panther platform cars, 97-00 F150/Expedition/Econoline, as well as 96/97 MN12s. Surely you can find one of those somewhere to grab the heads off of.
Thanks for that! You are right, i should be able to find some!
 
Anybody know where I can get (2) con rod bolts? Can't seem to find only two, just a complete set. I only pulled one rod cap. I didn't remember the bolts were TTY.
 
This number cross references with a 1995 Ford Thunderbird 4.6 when I checked on Ford Parts Giant.



 
This number cross references with a 1995 Ford Thunderbird 4.6 when I checked on Ford Parts Giant.
Yeah, I saw that. Looks like it's $4 and some change per bolt even though it shows 4 bolts. Is that about the going rate? I thought it was a bit much but maybe not...
 
While removing the valves from the heads on this car (95 4.6) I discovered one bent exhaust valve. No problem, I have spares. After some serious contemplation I have decided to re-use the 95 heads. I had a 95 4.6 Cougar that had 266K miles on it when it quit running so I know they aren't all that bad. I'm mainly doing this because I don't have to spend money to get better ones.

I have a question concerning lash adjusters and cam followers. Do new lash adjusters have some up and down movement before they are used? After I removed mine, the plunger pushed out the oil and would freely move about 1/8" up and down. I would like to reuse them since they are quite pricey for a set.

Cam followers are expensive as well. I've read there is a newer design that has a much smaller pushrod oil bleed hole to help keep lash adjusters hold pressure to help with followers falling off (this engine had 4 that had fallen off). I obviously want to keep my followers in place but I'm wondering if the old ones (if not worn) can be safely reused. I'm replacing the oil pump in case it was lower than expected oil pressure that allowed the followers to come out.

What do the experts (usually most folks beside myself) have to say?
 
I’ve never bought a new set of either. Followers especially unless you absolutely need the smaller bleed hole(which you won’t with those heads) aren’t really a wear item. Lash adjusters only really go bad because they get sticky/sludgy inside. Personally I just soak them in chemicals for a day and bleed them in a vice to “restore” them but I’m a cheapskate
 
I agree, Matt, but if they can't be freed up with a vice, they need replacing. I went thru 36 of them, and only got 4 good ones.
 
So tell me what the used lash adjuster behavior should be when checking them?
 
Just an update...

I ordered a set of main cap bolts and 4 rod cap bolts today. I'll start putting the engine back together as soon as they come in.

Replacing the oil pump and 2 intake valves. Valve seals come with the gasket set. Re-using cam timing components from the only 4.6 I ever rebuilt. 33K miles after the rebuild (266K miles total) the engine broke the conrods on the 3/7 crank journal. I rebuilt the engine in 2005 and just recently tore it down looking for parts.

I didn't know that high-mileage 4.6s were prone to rod breakage. I didn't check crank end-play when disassembling the engine. Can't think of anything else that would break a rod. I didn't really beat on the engine.
 
I wouldn’t say it’s a mileage thing, since I have seen many 300k+ mile 4.6s with no issue. I have seen a handful of broken rods in 4.6s, and for most of them I can’t say whether they were abused or not, but years ago my mother had a rod shatter on startup in a 98 Grand Marquis that was never beat on and always well maintained, so it may just be q random occasional failure and nothing to do with mileage or abuse, however the 4.6 is generally so durable that I wouldn’t worry about it.
 
This is what I found after removing the passenger side valve cover. I suppose two missing valve followers would cause a gallop, eh? :)
What happened to the missing valve gallopers? Maybe I missed it where you said you found them.
 
4 cam followers fell off, 2 bent intake valves, cam bearings in the head and cam journal damage on driver's side valve train. Small valve-shaped indentation marks on 7 pistons visible after carbon removal.

No cause found. Cams were correctly timed and no broken cam timing components. Inspected 2 rod bearings and they looked almost new. Same for the one main bearing I checked.

Going to reassemble with replacement driver's side head, 2 new exhaust valves, new main cap, rod cap (2), new head bolts and new oil pump.
 

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