I went over to Ford to talk to them about the truck. They said the compression test came out fine.

They looked in #8 with a borescope and could see something sitting ontop of the piston. They tried to move it with the borescope but it wouldn't move. They said something about sticking a magnet in there but can't remember if they said they tried that or didn't.

They also looked back up and saw marks on the head where that piece had been bouncing around and hitting.

With the compression test, will they still get a good compression test with scratches in the cylinder wall? I'm not postive on what bad scratches in the cylinder wall actually do (power loss? oil burning? increased wear?)... I just know it isn't good to have.

Also, do you know how much distance there is between the piston and the head when the piston is at Top Dead Center?

Thanks for the help,
David O.

 

Hi David,

By now, we've had a chance to go over all this via phone - and I'm glad to hear the compression test went OK, but whatever is on top of that piston has gotta come out.

Whatever is on top of the piston is either welded to it, or is bouncing around, as the combustion chamber is scarred and of course the spark plug that came out had it's ground electrode crushed onto the firing tip, so there was no gap, thus the plug could not fire causing a dead miss in that cylinder.

Whatever you do, do NOT run that motor anymore, at least until that foreign object is out of the cylinder - it's not enough to just replace the damaged plug and drive it, the damage *will* continue to get worse and worse. Right now, we don't know if it's a part of a piston ring or just a part of the damaged spark plug - shoot me some close-up photos via email & with good enough pics I can tell you if any part of the spark plug is missing - if it's intact but just damaged, then that's a piece of a piston ring on top of the piston, which means the piston & ring set in that cylinder must also be replaced - assuming the cylinder wall isn't badly enough damaged to absolutely require boring/honing.

As we discussed, now you are going to be evaluating the cost to repair this damage (which may be only $1000-$1400 or so) versus just going ahead and stepping up with a forged shortblock assembly and used your existing non-PI cylinder heads. And remember what we talked about re: the heads, those non-PI heads actually flow more CFM's than the PI heads once you are at about .490 valve lift & higher, so don't hesitate to have them ported & drop in a higher lift set of cams - either aftermarket or the Mustang GT cams. If you decide to go with aftermarket cams, let me know & I can get you a good price on a nice set and matching "beehive" springs, too - that truck is going to *rip* when this next stage is done - and it's only money, right?

Good luck & talk to you soon!

 

Mike, I posted this thread after our convo to let you know that the piece of metal was stuck on top of the piston. Before I just knew there was a piece in there.

They said the truck ran fine too. Maybe they took it on a road test also. They also didn't say a single thing about not driving the truck around at all. Even told me the "engine runs fine"

Truck's sitting still though. It's up in BR parked and I'm down in NO. Catching rides with people or stealing people's cars... sucks not having your own vehicle to drive around... lol... but I'm not having to buy any gas

I'm gonna start looking at my $ situation to see what I can afford to do. Would love to get that shortblock w/ non-pi heads w/ cams.

 

grrr... clicking all the wrong buttons with this touchpad... forgot my mouse...

 

Hi David,

Ahh, I see - so if I understand you correctly, what you're saying is that piece of metal is "stuck" to the top of the piston. Which would mean it's somewhat welded to the top of the piston.

Well, that is slightly better than just being loose & thus dancing all around the cylinder (would be nice if it just conveniently jumped out thru the exhaust valve when it's open), but it still has to be dealt with before running the motor again, IMHO.

Any idea what size that piece of whatever is?

I would imagine it's hitting at least one of the valves, if not actually striking other areas of the combustion chamber in the cylinder head each time that piston hits TDC (top dead center), from your description over the phone of damage to the cylinder head/valves they found with the borescope. That piece could potentially break off any time and, worst case, become lodged in between the piston & cylinder wall - scarring the cylinder wall & requiring boring & honing - or perhaps even seize the piston in the bore & snap a piston or rod - hopefully not, but you just never know.

Sure, with a fresh spark plug and no loss of compression, the motor actually should run just fine - but it's not OK to run it again with that piece of metal stuck to the top of the piston - you never know how long it's going to stay stuck there, or it's hardness & what other damage it may be causing, etc.

Sounds to me like it has to be dealt with - you shouldn't just leave a foreign object in the combustion chamber, even if the motor isn't missing or spewing obvious oil smoke, etc. - unless maybe you're going to trade it in at another dealership and let it be someone else's nightmare - not exactly ethical, but unfortunately, some people do things like that to others. I'd say that piece has gotta come out, and I feel they should have told you not to even start the motor again until it's repaired - who knows, maybe they just figured since you had been driving it for a while like that already, and with no compression loss or missing, etc., a little bit more driving couldn't hurt it any worse?

Good luck David, whatever you decide!

 

One minute I'm thinking DSS racing motor and the next I'm thinking putting a stocker back in there... Clearing out your bank account when in college isn't a good idea... too much alcohol needs to purchased and consumed.

I'm gonna start to deal w/ that rear end vibration that we talked about awhile ago as soon as I get these mid-terms out of the way. Not sure what I'm doing about the engine yet...

Maybe you want to send me a shortblock Mike. It's only money, right?

 

Hi David,

>>>Maybe you want to send me a shortblock Mike. It's only money, right? <<<

Ouch! Well said, & perfectly timed - good one, David!

It's always easy to spend someone *else's* money, you're absolutely right. And yes, drinking copious quantities of alcohol is something hard to give up, and I don't recommend it - speaking as someone who has to take a particular cholesterol medication that just isn't very conducive to prolonged liver function & drinking like I'd like to!

One option might be to just drop in another "stocker," like a Jasper engines rebuilt shortblock - so you have a warranty, etc., and it's not too terribly expensive - and just live with it until you can really afford to do a forged motor.

Or, since there is no loss of compression, you could take your chances and just drive it like it is, and just hope that piece of metal is already worn down enough to not hit anything anymore and pray it stays in place - or maybe jumps out of the exhaust valve, etc. I'd hate to see it come to that, but you do what you have to.

Why don't you just shoot me some pictures of the spark plug that came out of that cylinder, so I can go ahead and give them a good look-see & let you know what I think? When you asked me about that, I wasn't too positive about that, but you;re in a bind, so I'm willing to look at some good pics for you & let you know if I feel the metal on that plug could be from the spark plug - and if so, that would mean the piston rings are actually OK - thus the motor is worth repairing, etc. If you want to do that, I'll look at the pics for you.

Keep your spirits up, David - there's always that alcohol! (just kidding!!)

 

LOL, It's 4am and I'm up studying for a History mid-term and some how I found my way onto F-150 online during my studies... hrmm...

I'll have to get some pictures of the plug that came outta #8 to see what you think. Thanks in advance for taking a look at them.

I have a friend that is going to see if he can get some of the mechanics at his work to let me use their garage over a weekend. If it works out and they'll help me, then that'll save me a good $1000 that I was gonna have to pay for an install. It'll get me a little closer to getting that forged motor.

Baton Rouge isn't like New Orleans... The only way to survive is in an alcoholic haze... lol...

Edit: Question about the Mustang GT cams. Are the ones you suggest from the 2003 Mustang GT SOHC? Ford Parts Online has them for $180 for one and $165 for the other. How much lift do they have?

And someone else looked this up because I have been studying...

 

Hi David,

Yes, the "SOHC" cams is what any 2-valve Ford Modular V8 motor uses. The "DOHC" cams are always for the 4-valve motors, like the Cobra's and a few of the Lincolns - and they have a lot less lift, typically around .393 or so for the factory spec.


The GT cams are generally about a .505/.534 lift spec from Ford.

Yeah, it's been some years, but I used to spend a good deal of time in both Baton Rouge as well as New Orleans - and Shreveport, Bossier City, and on and on..............drinking is almost a requirement.

Good luck on getting access to the garage and doing the cylinder head R&R for a lot less $$$ - every penny you can save gets you closer to the built short-block!

I'll keep an eye out for the pics,