Does removing the valve covers make seeing spark plugs easier?

[jwakil]

I will be doing a leak down test and in the past ended up doing a partial drop so I could have line of site to the spark plugs from the sides, which allowed easier screw in of the test tool and replacement of the spark plugs without blindly trying to search for the hole and hoping not to cross thread, etc. Would taking off the top valve covers make the job easier so I don't have to do the partial drop? Is there significantly move visibility of the spark plug holes with those removed, or am I just making more work for myself? I've removed the covers for valve jobs and such, but can't remember if they made the spark plugs significantly more accessible.

I want to avoid partial drop so I can easily go into and out of gear when I'm trying to rotate the engine to a new cylinder vs when I'm doing a reading. With partial drop you have to disconnect the gear.

[fanaudical]

My opinion is that removal of the valve covers doesn't significantly increase visibility.

I'm not sure it's necessary to do the partial drop. Do you have lots of stuff in the way on the sides of the motor? (I'm not sure how much different a 930 motor is from my little 2.7.)

I generally thread in spark plugs by sticking them in the end of a piece of fuel hose and then using the hose as a "flexy/twisty" tool. It provides enough "feel" that I know the plug is started without cross-threading. I then put on a real wrench to torque the plugs.

I have a quick-detach hose for my compression tester that allows me to thread it into the plug holes in similar fashion. Perhaps something like that is available for your leak down tester?

Here's a link to a tool that seems to be assembled as I've described:

OTC Cylinder Leakage Tester Kits 5609 - Free Shipping on Orders Over $99 at Summit Racing

[Ronnie's.930]

No to the question of removing the valve covers.

No partial engine drop necessary for easy(er) access to the spark plugs - just remove the secondary intake manifold (the reciculation valve housing is another name for it), and all the associated hoses and so forth, on the left side, and disconnect the a/c compressor from its mount (no need to disconnect the hoses if you don't want to) and set it on thick padding on the right rear fender - plenty of spark plug access then.

[jwakil]

Originally Posted by Ronnie's.930

No to the question of removing the valve covers.

No partial engine drop necessary for easy(er) access to the spark plugs - just remove the secondary intake manifold (the reciculation valve housing is another name for it), and all the associated hoses and so forth, on the left side, and disconnect the a/c compressor from its mount (no need to disconnect the hoses if you don't want to) and set it on thick padding on the right rear fender - plenty of spark plug access then.

Well, I have tried taking off all the big rubber hoses that connect to the intercooler, and it was still a pain to do cylinder #1 without partial drop. Never could get confidence if I had screwed the tool in properly. I will research the secondary intake manifold removal.

[jwakil]

Originally Posted by fanaudical

My opinion is that removal of the valve covers doesn't significantly increase visibility.

I'm not sure it's necessary to do the partial drop. Do you have lots of stuff in the way on the sides of the motor? (I'm not sure how much different a 930 motor is from my little 2.7.)

I generally thread in spark plugs by sticking them in the end of a piece of fuel hose and then using the hose as a "flexy/twisty" tool. It provides enough "feel" that I know the plug is started without cross-threading. I then put on a real wrench to torque the plugs.

I have a quick-detach hose for my compression tester that allows me to thread it into the plug holes in similar fashion. Perhaps something like that is available for your leak down tester?

Here's a link to a tool that seems to be assembled as I've described:

OTC Cylinder Leakage Tester Kits 5609 - Free Shipping on Orders Over $99 at Summit Racing

The 930 engine layout on the sides is pretty much like the SC if you take off the intercooler hardware, and probably very similar to yours. Even though there is space on the sides, I still find it tricky to screw in from the side with a rubber hose that has to make a bend.

[boyt911sc]

Jwakil,

Just remember that the spark plug holes are oriented slightly to the right. The axis of the holes for cylinders 1-2-3 lean to the rear while cylinders 4-5-6 lean towards the front of the car. Once you did a couple of cylinders, you will have a better feel doing the rest. You could perform the compression and leak down tests without the need of an engine partial drop. The right side would be tigther in your case.

Tony

[jwakil]

Ok, I assume the secondary intake manifold is simply the big tubes to/from the intercooler which I had removed already. Nothing else in the way. After spending about 2-3 hours just on cylinder 1, trying to screw the rubber hose of the tool into the spark plug hole, I came to the same conclusion which I always came to (even with my SC): IT IS MUCH FASTER AND EASIER TO DO A PARTIAL DROP SO YOU CAN SEE EVERYTHING. IN THE END YOU WILL SAVE TIME AND FRUSTRATION. It would have taken me about half hour to drop it, and would have been able to do the first test in 15 mins. Anyway, tomorrow I will drop it, and even if I have to jack it back up for each cylinder to engage gears, it will still be faster. I did confirm that removing the valve covers is no help what so ever, useless for trying to insert anything into the spark plug holes.

[Ronnie's.930]

jwakil,

Sorry, I meant to respond earlier today with clarification about what the secondary intake manifold is . . . it is the manifold that is between the intercooler and the throttle body (the primary intake manifold is beneath the throttle body), and it houses the boosted air recirulation assembly (some call it a blow off valve, but it's not really, still a commonly used nickname).

If you remove that, it really clears out space to work on the left side of the engine bay. I always remove it whenever I have to get over there for something where I need a lot of room (like valve lash measuring/adjusting).

It can be a little daunting the first time removing it because there are several hoses and wires that have to be disconnected - much simpler if you don't have any of the emissions gear or deceleration valve in place, like mine.

Obviously you have to remove the intercooler, and there is a large o'ring on the throttle body neck that you have to keep care of (or replace). And just in case you are unaware of this, the best thing, by far, to use to lubricate that o'ring, and any of the intercooler o'rings, is silicone grease - can be found in the plumbing section of any hardware store. It is remarkably slippery, doesn't damage the o'rings, and does not evaporate or dry out. I have been able to re-use o'rings over and over as long as I first assembled them with that grease. I use it on any and all o'rings, for that matter, including ones for a/c systems.

Some pics of the manifold - the first one is of the left side and the very large hose from the fuel head's air metering assembly is attached to it, along with the hose coupling between the manifold and the turbo intake pipe. The second is the right side, and you can see that it is the large, black casting between the intercooler neck and the throttle body.

The secondary manifold is secured to the primary manifold by only three fasteners (two long bolts and one nut) - easy to remove once hoses and wires are disconnected.

[T77911S]

i just did another comp check on my 930. mine is not original so i have may have less than you BUT my metal pipe to the turbo is linger than yours making it harder to get to #1. i have not had any problems doing comp or leak down tests.
yes #1 is a pain but it can be done

[jwakil]

I have removed all that stuff. There is nothing in the way other than what would be for any 911 engine. Its still very difficult to screw in a rubber hose into the spark plug hole when the hose has to make a 90 bend. It would be great if I had a shorter metal tube to screw in to the spark plug hole, then screw the tool hose into that, but I don't.

[T77911S]

the valve cover actually helps.
use one hand to center the hose in the middle of the valve cover and the other to turn it.
it is tricky. you have to remember the angle of the plug is not straight in.
i have done it MANY times on my 930 and nlike i said. my #1 is under the metal pipe that goes to the turbo.
it helps to get the wire harness out of the way if yours is where mine is.

start on the right side with the easy ones and get a feel for how it goes in.
then do #3.

if your AC compressor is still on i remove mine from the bracket and lay it outside the engine bay on a thick soft blanket.

[jwakil]

Ok, I take back what I said. After trying a couple of more times, I was able to get the tool screwed into #1 without doing the partial drop, and got the 'feel' for how its done. The other cylinders were pretty easy, mainly because I learned the trick of how to bend the tube and screw at the same time. Too bad I will have to relearn the trick again the next time I do it. It always feels like next time will be a breeze but after a year, I can't even remember what I did, much less how I did it.