How hard is it to rebuild a 4.6 DOHC?

OP
OP
Venompower

Venompower

Active Member
Joined
Aug 17, 2015
Messages
627
Reaction score
333
Location
Batavia, IL
Haven't been on much lately and just read this. its always something isn't it?
Maybe... maybe not... this is my first non-factory supercharged car so my lack of history on it makes me a little nervous.

I'm also knocking stuff off the list, so hopefully at some point I'll just get years of reliable fun out of it. For what I spent on this car I'm waaaaaayyyyyy ahead.
 

BHernandez

New Member
Joined
Mar 7, 2022
Messages
72
Reaction score
30
If you decide it's something you want to fix, you should definitely do a timing chains, guides, tensioners and water pump at the same time. You'll have the engine out and great access to everything. You know what they say: "Do right. Do it once".
 
OP
OP
Venompower

Venompower

Active Member
Joined
Aug 17, 2015
Messages
627
Reaction score
333
Location
Batavia, IL
Any resources to rebuild step by step… links to the FSM, etc?

I should clarify nothing has changed, just trying to prepare in case it does.
 

lwarrior1016

Mr. Secondary Timing Chain
Staff
SN95 Supporter
Joined
Sep 22, 2014
Messages
7,209
Reaction score
2,249
Location
South Mississippi
Factory ford manual will always work. There is a book at Barnes and noble “how to rebuild ford 4.6/5.4” that I’ve read through a couple times and it seems to be really well put together. You could check that one out. I used one from that same company to rebuild an LS engine and it all turned out ok.
 
OP
OP
Venompower

Venompower

Active Member
Joined
Aug 17, 2015
Messages
627
Reaction score
333
Location
Batavia, IL
Factory ford manual will always work. There is a book at Barnes and noble “how to rebuild ford 4.6/5.4” that I’ve read through a couple times and it seems to be really well put together. You could check that one out. I used one from that same company to rebuild an LS engine and it all turned out ok.
Found a free link to the 96 DOHC FSM online, going to review this evening. I may also check out the book you referenced as I saw it on Amazon but didn't know if it was detailed enough.
 

BHernandez

New Member
Joined
Mar 7, 2022
Messages
72
Reaction score
30
You could always subscribe to: ALLDATADIY, as well. You'll have access to all of the factory and aftermarket information specific to one model car per license. It's like Chilton on steroids.
 

Silver95bird

Active Member
Joined
Sep 5, 2016
Messages
487
Reaction score
112
When someone says metal flakes, I think timing chain guides. I'd check them before going into a full engine build over it.
 

BHernandez

New Member
Joined
Mar 7, 2022
Messages
72
Reaction score
30
Timing chains guides are plastic, not metal. If the manage to get past your oil filter it doesn't appear as shiny but more lumpy thick residue. They usually deteriorate in large pieces and rattle like crazy. I'd be more suspicious of bearings or thrust washers.
 
OP
OP
Venompower

Venompower

Active Member
Joined
Aug 17, 2015
Messages
627
Reaction score
333
Location
Batavia, IL
Pictures for reference, it looks worse in the first shot because of bubbles in the oil.

3.jpg

After the oil drained, I rubbed my finger through that spot and this is what remained, way less particles than what it first looked like.

4.jpg

This is the pleats of the oil filter, which appear to have some small failed powder coat in them.

5.jpg

I drove the car last week with no issues, and drove it to work again today and it did fine. 196 degree coolant, no rattles, no piston slap, no ticking, just smooth... I'm planning on doing another oil change tomorrow, and using the Blackstone test kit and inspecting the drain pain again to see if the same particles are there.

I spoke to a local shop here that specializes in Mustangs, and they felt that it had to do with a bad powder coat job.
 

Attachments

  • 2.jpg
    2.jpg
    206.5 KB · Views: 2

96blak54

Legend
Joined
Feb 21, 2011
Messages
8,660
Reaction score
1,929
Location
In the shop
Well, .. its not any of the bearings. Judging by that debri, the first few miles would have reveled itself and you wouldnt be wondering. You would know for sure and wouldnt be happy. The same for the oil pump.

Are the shavings hard? Cut your fingers sharp? Magnetic?

Paint peeling from the underside of the valve covers would make alot of sense and for a reputable mustang guy to confirm such info is great.

If it isnt paint chips, Im banking on the timing chain guides worn out or something of sort. Although id be surprised, but not unlikely.
 
Last edited:
OP
OP
Venompower

Venompower

Active Member
Joined
Aug 17, 2015
Messages
627
Reaction score
333
Location
Batavia, IL
Well, .. its not any of the bearings. Judging by that debri, the first few miles would have reveled itself and you wouldnt be wondering. You would know for sure and wouldnt be happy. The same for the oil pump.

Are the shavings hard? Cut your fingers sharp? Magnetic?

Paint peeling from the underside of the valve covers would make alot of sense and for a reputable mustang guy to confirm such info is great.

If it isnt paint chips, Im banking on the timing chain guides worn out or something of sort. Although id be surprised, but not unlikely.
It’s non-magnetic and soft… doesn’t cut the finger. Car drove fine on the way home from work as well.
 

cobrajeff96

Active Member
Joined
Feb 1, 2022
Messages
678
Reaction score
546
Location
Germany
Could be just burrs from factory casting flash just flaking off. If that was all the shavings there was (in that pic of the oil pan) that's really nothing to worry about. It's one of the reasons they have those magnetic drain plugs to catch the small amount of shavings that most engines are going to produce.
 

Tillerman77

Member
Joined
Sep 18, 2016
Messages
175
Reaction score
50
Location
Southern MN
Could be just burrs from factory casting flash just flaking off. If that was all the shavings there was (in that pic of the oil pan) that's really nothing to worry about. It's one of the reasons they have those magnetic drain plugs to catch the small amount of shavings that most engines are going to produce.
+1. I use a Gold Plug on my 97 - inexpensive additional protection.
 

BHernandez

New Member
Joined
Mar 7, 2022
Messages
72
Reaction score
30
If it were bearings, there would definitely be some rattling noise with it, especially at higher RPM. Timing guides, I would also expect a heavy rattle especially on cold start. How's the oil pressure look? Does it flutter at idle? Is it strong at RPM? Have you tried using a bore scope in each cylinder? Could be block material from a bad rings, it is boosted, right?
 
OP
OP
Venompower

Venompower

Active Member
Joined
Aug 17, 2015
Messages
627
Reaction score
333
Location
Batavia, IL
If it were bearings, there would definitely be some rattling noise with it, especially at higher RPM. Timing guides, I would also expect a heavy rattle especially on cold start. How's the oil pressure look? Does it flutter at idle? Is it strong at RPM? Have you tried using a bore scope in each cylinder? Could be block material from a bad rings, it is boosted, right?
No cold start rattle, no weird noises at all… I’ll try to get a start up video and driving video, need to do it anyways as it’s dumped and I ordered tail pipes and want a before and after.

I’m ordering an oil pressure gauge as I just have the dummy gauge which consistently shows I have at least 6 psi of oil pressure lol.

I looked down the spark plug holes when I put the new plugs in and it looked fine but haven’t scoped it. I’d imagine if there was any significant damage in that regard I would know about it by now.
 

BHernandez

New Member
Joined
Mar 7, 2022
Messages
72
Reaction score
30
If it was me, I'd eliminate one by one for sure. Assuming something is good doesn't always work in your favor. I would start with a compression and leak down test. Eliminate the boar and stroke from the equation. Next, check all of your valve springs and rockers. Loose valve train components cans leave gliter. If all that works out good then you know for sure the problem is in the rotating assembly.
 

96blak54

Legend
Joined
Feb 21, 2011
Messages
8,660
Reaction score
1,929
Location
In the shop
Ill be honest. Some of the longest running engines had trash imbedded into the bearings upon tare down.

Whatever this trash is in the oil isnt good and raises for concern but it apparently isnt destroying the engine cause it would have already reared itself.

Get out and give it hell
 

BHernandez

New Member
Joined
Mar 7, 2022
Messages
72
Reaction score
30
I think your chasing a ghost. At this point, whatever it is hasn't caused enough damage to be discovered. Get out an enjoy it. When it starts to cause an actual problem, you'll have no doubt about what it is and how to fix it. I've seen these engines go 290K+ with broken guides rattling like hell and never being cracked open. Then you have others that get regular maintenance and fail at 80K. Run it. That's what I'm doing with mine. The engines themselves are plentiful and cheap. Even if you buy a remanufactured engine, they're around $3K for a long block. These things are made to take abuse in police cruisers, taxis and all kinds of unforgiving situations. Don't worry so much.
 

Latest posts

Forum statistics

Threads
76,399
Messages
1,476,554
Members
14,228
Latest member
5.0rnella

Members online

Top