What is the tightening sequence for my oil leaking car?

April 4, 2007 10:38 AM

Valve Cover Tightening Sequence for a 1991 Ford Escort GT?

I know it exists because I had to do this once before, and I'm pretty sure I used the wrong torque because I was using a torque wrench with ft/lb and not in/lb. I'm set to do it correctly now, but I seem to have lost the diagram I had to do it before.

I have a 1991 Ford Escort GT, 1.8 DOHC.

posted by gregschoen to grab bag (12 comments total)

The AARC guide I can get online through my library does not specify.

Rocker Arm (Valve) Cover
REMOVAL & INSTALLATION
1.8L Engine
[snip]
To install:
11. Position the gasket and rocker arm cover onto the cylinder head.
12. Install the cover retainers and tighten them to 43–78 inch lbs. (4.9–8.8 Nm).
13. Connect all vacuum hoses and install the air cleaner assembly.
14. Reconnect the spark plug wires retainers.
15.If equipped, install the two uppermost engine front cover bolts and tighten them to 69–95 inch lbs.
(8–11 Nm).
16. Connect the negative battery cable, start the engine and check for leaks.
posted by phearlez at 11:44 AM on April 4, 2007

Personally, absent any guidance, I'd use the alternating side methodology I'd use on wheel bolts.
posted by phearlez at 11:45 AM on April 4, 2007

Yeah, my shop guide does list that, but doesn't seem to have the bolt sequence diagram that I know I've seen somewhere, cause I remember holding a copy of it in my hands. Thank you for that info.
posted by gregschoen at 11:47 AM on April 4, 2007

Here they list the torque in foot pounds, and refer to a figure showing the sequence, but the figure is not there.
posted by MtDewd at 11:51 AM on April 4, 2007

Is the valve cover stamped steel (as opposed to cast aluminum)? If it is, and you tightened the bolts last time to X foot-pounds instead of X inch-pounds, you may never get a tight seal. Once the steel is distorted by over-tightening, no gasket can fill up the gap between bolts. If you're a fair hand with a hammer and dolly, you might be able to flatten the gasket surface. Otherwise, a replacement cover is in order.

If it's aluminum, you're probably OK, since those crack when overtightened, and you'd likely notice that.

If you can't find an official sequence, do this:
Snug all the bolts. Start tightening at the middle of one side, then do the middle of the other side, then one next to the first one, then the opposite one on ethe other side, and so on. Tighten in small increments until you get to the specified torque. The pattern should resemble this:

10 6 2 4 8
9 5 1 3 7
posted by Kirth Gerson at 12:18 PM on April 4, 2007

It is aluminum, I think that if anything I undertightened them. I realized after I bought the wrench that it was the wrong measure and we tried to do the conversion but it's rather hard to see somethink like 5ft/lb on a range of 1-75ft/lb torque.

I've noticed that I'm leaking oil from the front of the valve cover gasket, so I figure that I need to deal with it. It's only when the car is at highway speeds for sustained periods does it leak at all.
posted by gregschoen at 1:10 PM on April 4, 2007

I know next to next to nothing about car repair but I'm trying to help you.

Might you be thinking of a diagram for connecting cylinder head bolts?

The only information I can find that shows a connection order for your type of car (in a manual that gives the same instructions phearlez posted) shows this diagram for the connection order for the 1.8 engine.

Otherwise all the reference points say to "Tighten the cover bolts to 43-78 inch lbs. (5-9 Nm)", "Install the cover retainers and tighten them to 43-78 inch lbs. (4.9-8.8 Nm)."

Re-reading all this information, perhaps this is what you were looking for and I'm just confusing the terms. Here's a larger screenshot of the context of where the diagram came from, if that makes things clearer. It came from "Engine Mechanical > Engine Mechanical Components > Cylinder Head > Removal & Installation > 1.8L Engines"

I got this from the Chilton Library db. Hope it helps. If it doesn't, perhaps you can provide a different description, as I imagine what you're looking for is right here somewhere in front of me.
posted by cashman at 1:17 PM on April 4, 2007

It is actually what goes over that diagram you linked to. The valve cover is the cover for the head of the engine.

Here's a link to the procedure I'm trying to perform, except my valve cover is aluminum and sensative to the order the bolts and removed and replaced.
posted by gregschoen at 1:29 PM on April 4, 2007

If you want to wait, I will try to look this up for you tonight (think 10PM EST or even later.)
posted by qvtqht at 2:05 PM on April 4, 2007

I'm waiting for the torque wrench, it was purchased on eBay last night, so I have some time before I'm planning on doing it.

Plus, I want better weather, it was snowing today here in Wisconsin!
posted by gregschoen at 3:10 PM on April 4, 2007

gregschoen: Was cashman's answer what you were looking for? So far, all I have found is the diagram that he has already provided...
posted by qvtqht at 9:39 PM on April 5, 2007

FWIW, my data source recommends tightening to 76-81 Nm.

Removal order (going from outside in):

3 7 10 6 2
4 8 9 5 1

Tightening order (going from inside out):

8 4 1 5 9
7 3 2 6 10
posted by qvtqht at 9:47 PM on April 5, 2007