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Discussion Starter #1
So I'm in the process of swapping the cylinder head on my SPI since I found out they tend to drop a valve and the car already has 127k miles. So before it drops I decided to swap the head, already took the head apart, but I have a few questions while I wait for the gaskets to arrive.

1. What's the best way to remove the sprocket from the head? I tried using a screwdriver to hold the sprocket while I tried to get the bolt loose to no effect. I noticed though that the sprocket has a big nut, but I'm unsure the size if it's 1 3/8? can somebody confirm?

2. How do I set the new head to TDC so that I can install the sprocket?

3. What's the best way to clean the surface on the block where the gasket was?
 

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Need a manual when you get that deep, even a cheap one is enough.

Head bolts need replacement for example, they're TTY with angle torque to install.

Easiest cleaning depends on tools on hand, like I use an angle die grinder with Scotch buffer pads for gasket removal/cleaning (air compressor avail.).

Be careful with any scraping methods, don't want nicks in the surface.
 

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Discussion Starter #3
Thanks for the warning, i do have a manual in hand, but already tried the method to remove the sprocket, but it's too tight. It does not mention on what position should the valves be on the new head so I was hoping somebody that has already replaced their head would shed some light
 

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The basics of that question are easy enough to answer.

When you install & time the timing belt, #1 (& 4) piston will be a TDC and you want the #1 cylinder valves closed to put that cylinder on the top of the compression stroke.

Look at the timing mark on the sprocket & compare it to the instructions for setting the timing, for the SPI it's simple since the sprocket is fixed to the cam & it has a timing mark.
 

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Discussion Starter #5
Thanks, that's what i was thinking, but wasn't sure. I checked the old head and indeed the valves for piston #1 and 4 are fully closed while the valves for piston #2 and #3 are slightly open (1 intake and 1 exhaust). Now the only thing left is to remove the sprocket.
 

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Remember, 1 & 4 won't both be fully closed at the same time.

One set WILL be fully closed, the other set will be in a "even" state with some pressure on the valves toward open. 180* off between the positions.
 

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Use an impact wrench to take the bolt for the cam sprocket off. That is the only way i was able to get the one on my 98 Escort wagon w/ SPI engine off when I had to change it because one of the arms of the sprocket was cracked.

For the size of the bolt will be a metric headed bolt, on my car I believe it was a 15mm as it was one of the 2 sizes of sockets (other being 18mm) that didn't come with the Harbor Freight 1/2" drive shorty impact socket set that I have, but I was barely get the impact wrench with a long 15mm socket onto the bolt, but it wasn't fun getting it off.
 

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Discussion Starter #8
Thanks for the advise, i tried my electric 1/2 impact with no luck. Will try fully charging it as it only had 1 bar left. However, i think i'll have more luck using a big wrench to hold the sprocket as the sprocket itself has a big nut where the bolt goes into. I don't have a wrench that big with me right now, but i might have one in a toolbox in another place. I'll update on the situation as i don't get the gaskets until monday.
 

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I would be kicking myself right now if that were anatomically possible. I don't know how many times over the past 6-8 years I have seen the hex fitting on the cam sprocket, I have never once thought to put a wrench on it to hold it (though to be honest, I have only had to take the cam sprocket off three times, once to replace it, and the 2nd time to move it to a replacement cylinder head when I replaced it last year, and once when I had to redo the camshaft oil seal).

Speaking of the camshaft oil seal, if the replacement head does not have one installed, be sure to oil it up the new seal really good before installing it, otherwise it will be prone to leakage (hence the 3rd time I had to remove the cam sprocket).
 

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Discussion Starter #10
Thanks, I'm glad I'm getting advise from somebody who has done the same procedure already. By the way did you cleaned the bracket where the injectors are? i see some sort of little circle valves and are covered in carbon or something like that. Also Chilton's book says to apply a thin film of oil on the head bolts, but i read somewhere that you should never oil TTY bolts because it decreases friction?
 

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I did clean up the intake manifold runners and the ports on the split port manifold block/lower intake manifold (the piece the injectors mount to) with throttle body cleaner while I had it disassembled.

As far as the head bolts go, at least with the Felpro head gasket kit for the 97-99 Escort SPI which came with head bolts (strangely the 2000-2002 Escort SPI/2000-2004 Focus SPI head gasket kits do not come with head bolts despite for some reason both cost more than the 97-99 Escort SPI kit that came with head bolts (at least according to RockAuto.com)) they came pre-oiled, I can not say for any of the Focus SPI head bolt sets as I have never used one. While I do not care for the Haynes or Chilton manuals for a lot of things I would go by their instructions in this instance. (I prefer the model specific factory service manuals whenever possible, but the Haynes/Chilton books are good for quick reference plus they are inexpensive enough you don't mind getting them all oily and whatnot) . Also upon checking the 98 Ford Escort FSM it does say to lubricate the head bolts with engine oil, so I would definitely do that as I can not see why Ford would change that procedure on the same (basic) engine within a few years time.

One thing I would do however is run a blind hole/bottom tap into each of the head bolt holes in the block, to make sure they are free of debris and will provide a good thread mating surface (you should be able to get a blind hole/bottom tap at your local Napa store as that is where I got mine from). At least in my case that was especially important as a couple of the front center head bolts were a bit dry and rusty (the other 8 were fine but if I didn't use an impact wrench to take the bolts out one or more may have broken off in the block). I believe the size of the tap was M10x1.5 bottom tap, but bring a head bolt with you and they should be able to measure it to be sure. Napa M10x1.5 bottom tap is the link to the one I bought (a local store may not have one in stock but they can order it (I am lucky as a Napa warehouse (and for that matter an Oreilly auto warehouse is literally across the street from there) is on my way to work) ).
 

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Discussion Starter #13
Thanks Sailor, I anticipated this and bought an angle gauge. Would it be recommended to install the head with the intake on it? it seems very difficult to install it once the head is already installed due to the location of 2 bolts. I'm worried the weight of the manifold would not let the head sit properly and the TTY bolts would be more strained. Thoughts?
 

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That's a common choice to make, only caution is not to drop the head on the gasket hard at an angle when trying to set it in place. (crease it by hitting with a corner)

No problem when tightening the head bolts.
 

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Discussion Starter #15
Gotcha, another question, i was looking at the old head and i was turning the sprocket and found that the sprocket turns 1/4 of a turn at a time is this normal? After 4 turns you're back at the TDC marks. I also noticed a key on the bore where the sprocket goes into which means that i shouln't have a problem aligning the sprocket mark with the cylinder head mark right?
 

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Turnin' the cam will go in notches as the different valves open & close (always make sure a good head isn't sitting flat on a surface so the valves hit).

Sprocket on that one is keyed to the cam, so it will go on in only one position. (I think that's what you were asking)
 

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Discussion Starter #17
So if i install the sprocket on the cam as it only goes one way and if i align the sprocket tdc mark to the head tdc mark I'm assuming the valves should be in the correct position right? (closed on pistons 1 and 4. Also what happens if when the belt is installed it's off by 1 teeth?
 

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With the mark lined up, it'll be closed on #1, partially open on both #4 (no pressure on the first, some on the last set)

It's never exactly a tooth off, first step when not sure is to double check the mark locations for any little bit off then move the cam pulley towards the tension side (NOT the tensioner side) to drop the teeth into the notches.

Loose or tensioner side will pull tighter when the tensioner is set, bringing it closer to spot on.

When running, any free play in the tension side (pull from crank to cam) comes out so the cam backs off a touch, again bringing it closer to spot on when any error is made toward that side to begin with (crank turning pulls harder than your fingers).
 

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Discussion Starter #19
Okay so if I got this correctly I turn the sprocket clockwise towards the front of the engine. By the way thanks for helping with all these questions I really appreciate it.
 

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Yeah, clockwise engine rotation looking at the timing end.

Marks spot on, belt pulled tight at the front, you can rotate cam clockwise for whatever fraction of a notch is needed so the belt drops in.
 
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