Hello,

I've posted to this board quite a bit recently regarding my spark plug blowout problem on my 1998 4.6L F-150. I have encountered a very frightening point in this project and would really appreciate any advice you guys may have.

I realize that I've made alot of mistakes in process.. and I'm trying to take them in stride. I realize I have lost alot of money and time in this, but am looking for the best possible out.

Here's the story:

Around 6 months ago my #3 plug blew on my 4.6L Windsor.. I didn't really know what to do, because I couldn't pay the 3k Ford wanted to replace it.. So I heard about a heli-coil and got it.. A few weeks ago the heli-coil blew out as many predicted it would. The next day I called around machine shops and asked if they could do an alluminum insert on this and all the places I called said 'No'.. So I decided to order a head from a junkyard($275) and get it resurfaced/tested and pop it in. I took the head to the shop and got it resurfaced and pressure tested, and everything was fine.. brought it home and my mechanic friend tells me the valves are shot.. So I decide to take it to the machine shop and get the valves done. Just for the heck of it I brought my head with the blown threads in it with me to show them. When I get there they look at my blown head and decide its in way better condition than the junkyard head and discover that their tap(alluminum bigsert) or whatever insert thing can actually fit in it even though the holes been bored out already.. So they fix it $35 bucks.

I get back home and we start putting everything together.. I have my Chilton's manual out as well as another guide to configure the timing.. turns out my cam sprockets are nothing like these diagrams, but some patterns seem to give a basic idea. We pop it in and it runs, but a little rough... we decide to move it a tooth or two over on the passenger side and snap.. we hear a few small click type noises and realize we probably screwed the valves.. We pull off the valve cover and try and turn the motor over by the crankshaft and it only goes to a certain point and is locked now, even if we try and adjust the cam.. My mechanic friend says 'blown rod' or something like that.

So at this point I've about given up.. and don't know what to do but I'm positive I don't want me or my mechanic friend going any deeper into the engine. Somehow I managed to spend about $1500 bucks on parts some that I didn't need and some that are wrong, and tons of time ordering the parts and working on the truck... This isn't small change for me.

I owe 7k on the truck it has 119,000 miles.

What should I do?

Ideas that I have and would very seirously appreciate advice on:
-buy rebuilt engine? how much are these?
-take apart and fix this current one?
-put my truck in the auto trader and see how much I can get for it with no engine and cut my losses?
-take it to junkyard and see if they want to buy it?
-part the truck out on ebay?

I hope I didn't give too much or too little information.. I'm just really worn out and am looking for some advice from people other than myself

Thanks for your time.

 

You have an interferance motor. What that means is, when any valve is open all the way and the corresponding piston is trying to move to the top of its stroke it will hit the valve. And that is most likely what happened when . Stay away from your mechanic. He is not your friend. Ok enough about that. Pull the head off and inspect the damage. If you are lucky you "only bent a valve" Let me know what you find.

Regards

Jean Marc Chartier

 

Sounds like a valve or three broke. All mod motors are interference as Jean said, and if the cam timing isn't right, bad things happen. Ask me how I know...

The next step would be to pull the heads back off and see what exactly broke. You could look for a used engine, call around to different Ford dealerships in the area. Lots of them deal with companies that specifically supply used parts for customers who want to go that route to try and save a little money. Most times, dealers will try to go with the best sources for said used parts to try to minimize the chance of a return repair. Those are the guys you want to deal with.

Or you could buy another long block. Don't bother with Ford on this one, go Jasper. Or, if just any valves broke, you could replace the offending valves or heads depending on how significant the damage was and retime the motor. If you should decide to go this route, lemme know, I'll get ya the factory directions on how to set the cams back up.

 

Thanks guys, I appreciate the information.

We twisted the cam different ways and the engine still wouldn't turn over.. does this mean that the rod is bent?

We only removed one cylinder head, does this mean the bad timing and damage is only on that side?


Thanks

 

If you set the timing wrong on the head that is still on it may be casuing the jam. As Quintin said pull both heads to see.

JMC

 

If I've never adjusted the timing on the drivers side head, do I still need to pull it? Like can the passenger side timing have an effect on the valves on the drivers side? THanks

 

Ok, if you never touched the driver side then it should not have moved. The Crank gear on the driver side is behind the passenger side so you should not have touched it if you only did the passenger side. Now if you do not remove the damaged head you will cause even more damage by trying to turn the engine. The chances are you only bent valves. Take it off and have a look.

JMC

 

If I take off the head.. How much for new valve job roughly?

How much would a place charge to do the timing(roughly)?

None of the 3 different books and print outs I had were accurate.. I had no copper chain and different marks etc.

My head says 5.4L on it but my engine is 4.6.

 

If I only bent the valves do they still need to be replaced or does that just mean I buy new ones?

Thanks

 

A bent valve has to be replaced and if it damaged the guide and possibly the head it must also be repaired or replaced. It could have also damaged the piston. The extent of the damage will not be known till you pull the head and inspect. Your mechanic friend may have casued you a lot of greif through his ignorance of these engines. Under no circumstance do you turn the crank of an interference engine unless you know what you are doing.

JMC

 

I have an extra head that has been surfaced and is ready to go.. the valves in it aren't as good though so they probably need to be cleaned up by a machine shop.

I'm thinking of just getting a valve job on this replacement head I have and finding someone that knows how to do the timing on this thing.

Sound like an ok idea?