1997 4L SOHC chain replacement

[4doorXLT]

Spring has sprung and I need my truck. I have read as much as I can read and I'm going for it. If I understand everything correctly it isn't going to be too bad. I am fortunate that the right side is ok so I can set #1 on compression and go from there. It seems to me that the whole works can be reassembled with the priority on the right side, crank to jack to cam then I can rotate the cam on the left until parallel and tighten. Sorry if I am making it sound easy, I'm sure it will not be.

In an effort to make sure I don't get the left cam 180 degrees out someone made reference to the center cylinders (#5) cam lobes position. Can I ask someone to clarify this for me?

Also, on the 97 do I have to remove the front bolts from crankshaft reinforcing (support) block?

This is going to be an interesting project!

I HAVE TO GET MY TRUCK BACK< I MISS IT

 

[2000StreetRod]

What to replace?

What are you planning to replace?

Did you visually inspect the right guide assembly?

 

[4doorXLT]

I'm almost ready to start pulling the front cover, everything else is off and out of the way. I am hoping to replace the left side chain assembly only!
I have yet to inspect the right side!

 

[2000StreetRod]

may be some surprises

If your left front guide assembly needs replacement there's a good chance that your jackshaft tensioner is worn too. It is very difficult to replace the left guide assembly without loosening the jackshaft sprocket. If the jackshaft sprocket bolt is loosened the right camshaft timing will have to be redone. It is impossible to replace the left timing chain without removing the jackshaft sprocket.

 

[2000StreetRod]

left camshaft position

The photo below shows the correct position of the left camshaft when the #1 piston is at TDC on the compression stroke.

The green arrow identifies the protusion on the camshaft that triggers the camshaft position sensor. The notch on the rear of the camshaft must be below the centerline of the camshaft and parallel to the surface of the head that mates with the valve cover. Accuracy is very important!

 

[bluestream1]

I'm almost ready to start pulling the front cover, everything else is off and out of the way. I am hoping to replace the left side chain assembly only!
I have yet to inspect the right side!

The primary chain tensioner from the factory is just a POS; 3 small leaf springs and no oil pressure. This will have to be replaced as well to do a proper repair or it will rattle at 2400-2800 rpm. The new part has a stronger base and a 6 leaf spring. Replace the primary chain guide as well; it is cheap

 

[2000StreetRod]

Jackshaft chain tensioner

I agree that the jackshaft chain tensioner is significantly improved and for $29 worth replacing.

 

[4doorXLT]

I appreciate the replies and pictures.

Thanks!

 

[4doorXLT]

Latest news

I have the front of the engine torn down, all that's left is to pull the pulley and the cover. My wife came in today to see our baby, she's not happy! While she was there I said lets find TDC on #1. Bottom line, I have 0 compression on the right bank and 150 Lbs on the left!

I'm so upset!
It's a character building job now!

 

[2000StreetRod]

Bad news!

In your initial post you stated that the right side was OK. Did you ever pull the right valve cover and inspect the right timing chain and guide?

Did you check the compression on all three right bank cylinders? There's a chance that the chain slipped instead of breaking. The right camshaft timing can be adjusted without pulling the engine. I again suggest that you pull the valve cover and visually inspect. Further compression testing may cause additional damage so I advise against it.

 

[4doorXLT]

I assumed given the area of the engine noise that it was the left chain; I now know different. If the right chain slipped I'm sure it will still have to come out unless I'm really lucky and it's in the front which I doubt. I'll pop the covers and confirm its the rear chain.

I was really just hoping it wasn't worst case!
Dealer told me they installed a short kit prior to my purchase date! I'm guessing that's everything but the rear chain :thumbdwn:

 

[2000StreetRod]

Chain slip vs break

I assumed given the area of the engine noise that it was the left chain; I now know different. If the right chain slipped I'm sure it will still have to come out unless I'm really lucky and it's in the front which I doubt. I'll pop the covers and confirm its the rear chain. . . :

The engine only has to be pulled to replace the rear chain or guide assembly. The camshaft can be retimed with the engine in place and the valve cover removed. If the chain slipped and a valve was bent the head can be removed without pulling the engine. Hopefully you were lucky and the chain slipped and there is no engine damage.

 

[4doorXLT]

Confirmed, it's the right chain. The back of the valve cover exploded when it let it go, I can see the chain! Good news is the engine is almost out already! Once on the stand I'll see what I can see. My best approach I guess would be to buy the parts and do a compression test and see what I have. Good news is I have found another 4.0l SOHC with 100,000 miles on it for 600.00 bucks. I would like to keep what I have but I'm up to 140,000 miles.

We'll see how it goes on Sunday!

Funny, I am enjoying the job!

 

[2000StreetRod]

Broken chain?

Confirmed, it's the right chain. The back of the valve cover exploded when it let it go, I can see the chain! Good news is the engine is almost out already! Once on the stand I'll see what I can see. My best approach I guess would be to buy the parts and do a compression test and see what I have. Good news is I have found another 4.0l SOHC with 100,000 miles on it for 600.00 bucks. I would like to keep what I have but I'm up to 140,000 miles. . . .

So you have confirmed that the rear chain is broken? If so, I assume that the guide assembly is also destroyed. You can purchase a rear cassette (PN 4L2Z6M290AA includes Guide assembly, Sprocket/gear-camshaft and Sprocket/gear-jackshaft rear) online for about $68. You'll also need a jackshaft rear sprocket retaining bolt (PN W703167S430) and a Cover assy/rear of block jackshaft opening plug (PN F77Z6026AB).

 

[4doorXLT]

Thanks, I sure appreciate this help. I have been quoted $180.00 bucks for a rebuild kit for the rear assembly. It sounds high compared to the prices you list!
I'll do some more checking around!

Thanks again!

 

[2000StreetRod]

possible sources

I don't know if you can buy online. If so,
tascafordparts.com
touselyfordparts.com
silverstatefordparts.com

 

[4doorXLT]

Thanks for links!


I'm stuck, the job has been going along well. Ford actually did a great job of making a lot of stuff easy to deal with but, there is one bell housing bolt I can not reach. I have successfully wasted 2 hours trying to get it; it is the last bolt before pulling the engine! Any tips?
It's on the top of the drivers side; there is a bracket stopping me from getting at it from the top. This one is building a lot of character LOL

 

[janolsson]

Thanks for links!


there is one bell housing bolt I can not reach. I have successfully wasted 2 hours trying to get it; it is the last bolt before pulling the engine! Any tips?
LOL

Loosen off the tranny mounts to drop or raise the tranny a little to increase the gap from the firewall. Then go in thro the fender with the wheel off. If irc i was able to get my breaker bar with a socket to start it loose and then it was easy with a 13mm flexihead ratchet spanner.
hope this helps

 

[4doorXLT]

Thanks for the reply. I was back it at today and managed to sucessfully remove the engine.

Update:
What a mess, with the engine out and leveled I was able to remove the front pulley and front case. Looks like every tensioner accept one (large block on the right looking at the crank) is in pieces. I went to the ford dealer to get some parts ordered, not much help.

Looks like I'll be busy for awhile.

Interesting note, when i pulled the valve cover on the right side, one rocker arm was off sitting to the side of the valve and I can remove the others without compressing the springs. It has been sitting for 7 months though, concern?

Good news:
There is a lot of slack in the chain, turns out the rear chain is not broke, looks like it skipped a tooth or two or three. I may not have any serious damage!

 

[BobWiersema]

Doesn't sound good. You most likely smashed some valves, same thing happened to my first engine. Once you get the heads off you will know more.

Save this link, just in case your local machine shop cant save the heads or wants to much money.

http://cgi.ebay.com/ebaymotors/FORD...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

Bob