Help Diagnose my intermittant Missing Problem

[V8BoatBuilder]

Use alot of RTV on the front/rear part of the lower intake gasket instead of the gasket itself.

Ok... the Fel-Pro kit I have for the lower intake included regular gaskets for the head-to-intake passages, but some funky, rubbery ones for the front/rear ends. RTV seems like a good call.

 

[james t]

Throw the end gaskets in the trash. They NEVER work and allways leak. Use mucho RTV. Make a big trailer park booger glob of it on there. Trust me, it works.

 

[dogfriend]

Some questions:

1) I have the Graphite FMS head gaskets, they look really nice. Do I need to put any kind of sealer/grease/etc between the gaskets and the block or head????

2) What about the intake manifold gaskets?

3) The cylinder head bolts do not need retorquing, correct?

1) You shouldn't need to use anything on the head gaskets unless the replacements specifically call for it.

2) Either RTV like JamesT says or use the gaskets in the kit with minimal sealent.

3) If you torque correctly, you shouldn't have a need to retorque and I think you risk getting a leak if you back off the torque in order to retorque the bolts. From my Mech Engr background, you should only torque the bolts to the proper torque one time because you are stretching the bolts (permanently) during the torquing. Use new bolts according to Ford (see below)

 

[ammo troop]

1) You shouldn't need to use anything on the head gaskets unless the replacements specifically call for it.

2) Either RTV like JamesT says or use the gaskets in the kit with minimal sealent.

3) If you torque correctly, you shouldn't have a need to retorque and I think you risk getting a leak if you back off the torque in order to retorque the bolts. From my Mech Engr background, you should only torque the bolts to the proper torque one time because you are stretching the bolts (permanently) during the torquing. Use new bolts according to Ford (see below)

I agree, save yourself a future headache and get new headbolts! Man, I wish I was as organized as you when tearing apart a truck, I always end up with extra hardware and such!...Good luck on the reassembly!

 

[Glacier991]

Never a bad idea to run a tap into the bolt holes first either! More accurate torque readings that way

 

[V8BoatBuilder]

Important Question!

The cylinder heads are sitting on their dowel pins, ready for bolt torquing!!

Questions:
1) I have new ARP cylinder head bolts/washers. ARP says to NOT use Ford's torque spec, but to use their own of 85ft-lbs with the bolts coated in 30wt oil. (65ft-lbs with ARP Moly Lube, which I do not have). Ford says to torque to only 55ft-lbs, then rotate the bolt 90 degrees further.

Should I go with the ARP instructions? Could this extra torque damage the head gaskets? Is there any extra torque when the 90 degree turn is factored in?

2) The upper 5 cylinder head bolts (under valve cover) in each bank go into blind holes. However, the lower 5 (exterior ones) extend into the cooling passages. ARP recommends to use Thread Sealer on these bolts. Should I screw it and just use the 30wt oil, or use loctite?

 

[Cali' Explorer]

Boatbuilder.

1.) When you turn it another 90 degrees, you will push the 55 ft-lbs. From my experience working on engines, 90 degrees could be enough to push it up to 85 ft-lbs. My guess is they gave that number because "Torque to 55 ft-lbs and turn an additional 90 degrees" is fairly vague. What's 90 degrees to you might be 120 to me, plus you don't get them all even.

What I typically do is torque them all down in the order listed to about 1/2 of what I need (In this case, about 30 - 40 ft-lbs.) and then go back and do them all to the proper torque. Once they are all torqued, I hit them one more time just to be sure (3 times seems to give you an accurate reading).

2.) Hmmm. I would personally use 30 wt oil on the bolts themselves, but surround the holes with RTV or Silicone to seal the area around the hole. I would just run a thin bead all the way around so that the bolt is sealed after you install it.

Just so you know, the purpose of the oil is to ensure that the Torque readings you are getting are from the pressure of the bolt and not from friction in hole. If something were to get clogged in the hole or on the bolt, it would affect the torque.

Also, the speed you torque at is important. Trying torquing fast, then do the same torque spec and do it about 1/4 the speed. You'll get another 1/4 to 1/2 turn at least out of it.

Last, I wouldn't worry about the head gasket, that much extra torque isn't a big deal for a gasket. It would only cause a problem if you put it to 85 then released it some. You should be fine.

 

[dogfriend]

^^^ What he said.

The 85 - 90 deg turn would most likely get you close to the 85 lb ft.

A lubricated bolt will get more "stretch" at the same torque setting because you minimize the friction in the threads. The whole purpose of torquing the bolts is to impose a controlled tensile load on them. Without writing a long explanation about this, it has been determined that imposing a tensile load on the bolts at all times reduces the possibility of fatigue failure of the bolt.

A quote that I remember from my Mech Design text (Shigley) "If the bolt does not fail due to the load applied by torque, it will likely never fail". This is because the preload will make sure that the bolt is always in tension minimizing the possibility of fatigue.

 

[V8BoatBuilder]

Thanks for the support guys - its awesome!! Both in this thread and the torque wrench thread.

I've been spending lots of time over at www.corral.net (Don't worry... I'm not going far; haven't even posted yet ) and there is TONS of info on building 5.0s. I have been able to find lot of answers.

The heads are both on a torqued down, went pretty smooth. I did have a bit of trouble muscling the heads into the truck, ended up getting my Dad's help and rigging some "handles" on the heads out of rope to get them in and angled properly.

I'm now re-assembling the rockers/pushrods.

1) Should I put locktite on the rocker arm bolts?

2) For adjusting the rocker arm bolts, the guys over at Corral (as well as an install manual from Comp Cams) say that the cylinder being adjusted should be at TDC, with both valves closed when torquing down. Neither my Ford CD or Chiltons mention anything, they just say torque to 18 to 25ft-lbs. Is this procedure just for roller rockers and not my stock stamped steelies?

Thanks.

 

[Glacier991]

The benefit of TDC is a more accurate reading... how much more???? I have never used locktite there, but blue locktite never hurt anything, I just question it's necessity. Even in HP/race engines where they use safety wire headed bolts, I have never seen those bolts safety wired.....and God knows I have strung a bunch of safety wire on rod bolts (with measured weighed wire), cap bolts etc.... and gawd knows what else.... maybe ought to tell us something? Others with more current engine rebuilding knowledge may have better info. My engine building days are rather dated. (Pre the days of mic'ing bolt stretch for example...)

 

[dogfriend]

I agree with Glacier; you will get a more accurate torque on the bolts because you will avoid the possibility that the pushrods are pushing on the rocker while you are tightening the bolts. I can't see where Locktite would hurt anything.

 

[V8BoatBuilder]

Almost done!

Been a few days since the last update, but with work, time on the truck has been limited.

She's almost back together and ready to be fired up. Only thing that remains is the installation of the ingition wires. My new Taylor Spira Pro wires from Summit came with only SEVEN wires in the box!!! Can't run an EIGHT cylinder truck on SEVEN spark plug wires. Note to self: count the wires, don't just look at them when the order comes. Now I have to wait untill tomorrow, as they are overnighting a new set. I could mix/match the new Sipra Pros with my old set, but a few of the ends on my old ones broke, so they're out.

Everything else (except fenderwell trims) is assembled and ready to go, the engine is filled with fresh fluids, and I'm excited! I have lots of photos of the teardown/rebuilt, and I'll be uploading them shortly.

 

[V8BoatBuilder]

Photo Update

Here are some photos I snapped of the re-assembly. There were some key steps that I didn't get shots of, or they came out really blurry.

Cleaned Block and Piston tops:

Driver's Side

Passenger's Side

I used Permatex' spray on gasket removed and single edge razor blades to clean the block surface. Some overspray got on the piston tops, and lifted the carbon right off!

Painting
In the downtime while the heads were being machined, I broke out the wire wheel and rattle can.

Primed Valve Covers

Upper Intake..... shiny!

Refurb Heads
I took the heads to Whitaker Automotive, in Needham, MA. Recommended to me by a local Ford dealer, I was impressed by the machinist when I talked to him and saw his work/shop. This was a very blind item for me, as I had no basis or other recomendation for a shop.

$385 later:

Head Installation
These cast iron heads were quite heavy, and hard to maneuver. I rigged up some handles on them to allow lowering into place. I put in an exhaust manifold bolt, attached some line, and looped through a pushrod hole. The handles not only allowed for easy grasping of the head, setting the angle for lowering onto the dowel pins was quite simple. (I didn't think of this method untill after my Dad and I tried to lower a head in place, but only busted the head gasket in the process. Luckily Autozone has good felpro gaskets for $13.99ea. Order Extras.)

I also rigged up a 1"x1" steel tube across the rear of the engine compartment, allowing true lowering of the head into position. Made things infinitley easier.

Lots of n/c brake cleaner was used to make sure everything was squeeky clean. Don't tell WallMart execs, but I think I'm still high from it. :smoke:

Reassembly
Ok.. so I don't have photos of head bolt torquing, valve train re-assembly, or lower intake gaskets. :fire:

But, I did grab this photo of the new Motorcraft t-stat ready for installation.

Lower intake, fuel injectors, valve covers, alternator, belt, upper radiator hose:

Note: Tin foil should yeild +45hp

Upper Intake, EGR Eblow, Throttle Body, Ingition Coil Bracket:

More to follow!

 

[performancenut]

Strong work!

 

[V8BoatBuilder]

It Runs Great!

UPS man came today at 10am, and by noon, the truck was all set.

IT RUNS AWESOME!



It instantly started up and was very smooth, and during my short test drive performed AMAZING. Very smooth, very fast.

All that's left is to put in the new O2 sensors, re-install the fenderwell plastic, and let the PCM re-learn. :smoke:

 

[85Dave]

Congratulations!!! Don't forget to change the oil.

 

[performancenut]

Yes- congratulations.

 

[Glacier991]

GREAT JOB Aaron! Thanks for the posts and pics. A very helpful thread. I'm as delighted for you as if it were my own! I'm going to suggest they rename the thread and post it Useful Threads... if others agree, urge them to do so. Excellent on upper engine rebuild!

 

[performancenut]

So Aaron, as you wind down and get things back and finely tuned, can you in retrospect blame the whole miss issue on the head gasket?

 

[V8BoatBuilder]

THANKS to everyone for all the help on the project, I could not have done it with only shop manuals, and no advise. The people on this forum are truly amazing.

As for whether the head gaskets were the problem or not, its tough to say. The machinist found loose valve guides, and the #2 valve was not seating. When he went to grind down the valve, the seating surface was not even. Ah-Ha!

While the engine itself is running great, I think the exhaust is somewhat plugged/restricted. I need to get a backpressure gauge and find out for sure. The truck has LOTs of power down low, but when it really starts to move air around 2500rpm, power ceases to build. It is also VERY loud through the MAC intake, much louder then I remember it being.

Question: If there is a partial blockage of the cats or muffler, can this damage the motor?