97 SHO - How do you know if cams going?

[jbruno72]

I've had my SHO for about 4 years now. It has 125K miles.

About 2 weeks ago it started idling rough and ran rough especially at lower rpms under load. Cruising on the highway, I felt surges.

It sort of felt like the transmission was slipping so I took it to a shop. The fluid was varnished but the tranny was fine. After the fluid purge and change the car was just a little better but not much.

Took it to a regual engine place and they found a bad intake gasket, 3 different types of plugs used, a missing egr? gasket, etc.

They fixed everything (coils fine, FI fine, fuel filter changed, etc.) and tuned the car. The mechanic drove it and heard pinging and suggested I use premium gas. After stating that it doesn't require it, I said I'd give it a try at the next tank (hasn't happened yet).

However, I got to thinking, could this be the cams? It still runs rough down low, the check engine lights is on (and sometimes flashes) and I hear a ticking sound.

Please let me know if this is what one would experience if it was the cams. The mechanic wasn't sure what it could be (did not seem familiar with the cam issue), but said try premium and then bring it back if it did not resolve the problem.

Any thoughts are appreciated and please let me know if more info is needed.

 

[93rev2sev]

Since I have not actually seen or heard an SHO V8 cam failure, I would like to know if I have the correct understanding of cam failure. I know the engine is an "Interference" engine. Meaning: if the valves are not closed by the time the piston reaches Top Dead Center, there is a collision of the two(well 3), causing SEVERE piston/rod/crank/etc.. damage.

My understanding...please correct me if I'm way off on anything:

Design and assembly flaws work together to cause this failure
Design flaw: The cam sprocket should be welded in place on the cam shaft. It isn't. Some bean counter somewhere asked an engineer if there was a cheaper way to connect the two pieces - without costing the warranty department any forcasts. He said (probably jokingly) "ya, you can rivet them together". By "rivet", I mean the sprocket slides over the end of camshaft, which is hollow. A steel ball bearing is then jammed into the hollow end, expanding it and holding the sprocket in place. As age and vibration take it's toll on that connection, the cam starts to break free of the of the sprocket. Maybe it just wiggles a little bit at first (tick tick tick), maybe it slides half way around....BOOM...collision, "thank you, Ford...may I have another".

Assembly flaw: If the camshaft, the sprocket, or the ball bearing are the wrong temperature during the riveting process, delicate metalurgical(any metalurgists out there?) phenomena occurs weakening the connection.

A simple bead of weld around the cam sprocket/cam joint ensures endless "cam failure-free" miles.

 

[NebraskaSHO]

The design problem (from what I understand) is that the gear was not pressed onto the camshaft in the right manor. It's stuck on their with splines and everything, but they are not capable after time to hold the gear in place. Welding reinforces and keeps the gear from moving.

Maybe if they would have used a different type of metal (or something different) it might be able to hold.

A simple bead of weld around the cam sprocket/cam joint ensures endless "cam failure-free" miles.

Not always, there have been some cars that we're welded improperly and a cam has slipped.

And if it's running rough, and making a ticking sound, I wouldn't restart it until you can check the cams. I just hope it wasn't sounding like this:
http://www.v8sho.com/SHO/wav/MotorClick1.mpg
or this
http://www.v8sho.com/SHO/wav/MotorClick2.mpg

And also, after four years how could you not have had the cams welded? Sorry had to ask.

 

[warmonger]

ahhh the legendary tick of death!!!!
my understanding from lots of research when i was looking to pick up a 98sho,was that the same design was used on the mustang cobra(?) 32v as well. and that there have been reports of similar problems,only on a much much much smaller scale. mainly because the rev limiiter on the mustang was lower....dont know the validity of that,but thats what i read...

 

[NebraskaSHO]

Same problems on the 4.6L/5.4L. As you mentioned, they don't quite run as quick.

It's not SHO specific, but they did leave the SHO flappin in the wind.

EDIT: Can't type tonight!

 

[jbruno72]

OK, I started up the SHO and there is no audible ticking sound at idle.

Obviously, something is wrong though and I was wondering if their was someone in the Philadelphia area who knows how to work on these cars.

Thanks,

 

[NebraskaSHO]

Are you sure the coils are good? Mine stutters once in a while, then clears itself out and will run just fine. When one is completely out it will miss pretty bad.

Also usually it won't throw a code for a miss, unless it goes on long enough.

 

[warmonger]

they sure did,kinda similar the contour/2.5L duratec...almost as common to spin the #6 bearing in the 2.5L as it was for the cams to fail in the 3.4L....yet ford never owned up to there being a "epidemic",even with engines failing as early as 30k miles....kind of ironic now that i think about it...the engines share the same "platform" if you will...the 3.4L is essentialy a 2.5 duratec with two more cylinders and yamaha heads...ford most of really hated that engine..lol

 

[NebraskaSHO]

Granted the V6 SHO's are now anywhere from 18 to 12 years old, but from what I've read on here, they seem to have quite their own problem with rod bearings and diff pins.

It is just a Ford though.

 

[warmonger]

yeah...i wasnt aware of the bearing problem till recently...kind of worrys me know...its kinda the reason i let my svtc go....but i'm thinking i'll bite the bullet and change them...

 

[jbruno72]

I e-mail Kirk from nesho.com and he thinks it is the coils as well. The question is do you have to take each one out and test it somehow? The first place I took it to tested the #2 coil and they said it was fine. The 2nd mech said he was seeing the code for the #3 cylinder misfire. I do not know if he checked that coil.

This is getting expensive

Any affordable SHO mechanics or someone who likes working on SHOs near Philly?:wave:

 

[Mr Anonymous]

Flashing SES light is almost always a bad coil. Last mechanic took you for a ride, I hope he lubed you up first.

Of course you could slap a brand new coil on there today and spin a cam tomorrow, so I'd suggest putting welding on the top of the list since replacing the offending coil at the same time is easy.

We get customers from Philly all the time, although we'll be in Warrenton, VA on Feb 3 and 4 so you'd be around a 3 hour drive to get your cams welded and get the car running right.

 

[warmonger]

yeah...i'd take his advice...hate to see you dump money into....than see you parting it out two weeks later because the cams failed and your engines toast....although i'm always in the market for sho bumpers and wheels...???

 

[jbruno72]

Can it be driven with the bad coil(s) without damaging something?

 

[Mr Anonymous]

Can it be driven with the bad coil(s) without damaging something?

Usually driving with a bad coil for a couple of weeks isn't a problem, but long-term you could end up with issues.