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Old 09-02-2011, 03:53 PM   #21
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Re: VX getting lousy FE lately, what are the causes?

Great quality on the photos!

You used less anti-seize than I did. I am not qualified to comment on the actual condition of the plugs...
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Old 09-02-2011, 04:35 PM   #22
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Re: VX getting lousy FE lately, what are the causes?

^I used slightly less this time on all 4 new ones just now.

Yeah, I went ahead and replaced all 4. Cylinder #4's plug removed easily, and is not degrading as I had feared. Perhaps installation this last time 'cleaned' the threads on #4, I went by feel more relaxed this time, so I only did a half turn(with 3/8s wratchet+extension+plug socket)...once hand tightening needed more than wrist/hand turning(slight forearm strength) that is.

Also, I checked the plugs in the photos above(with 4,000 miles on them) to the ones I pulled back in June which had around 20,000 miles on them. They did not have any of the scorching on the side of the 'ceramic?' part leading up to the electrode. Also, the arms didn't have 'flaky'; bake on anti-seize 'like', material as these plugs I removed today had.

I'm about to go for a test drive.

Not sure if running the Red Line SI-1 as concentrated as I did(mistakenly overdosed using the entire bottle to the 10 gallon tank) would cause that discoloration, but it worried me compared to the originals none-the-less.

So, for $8.86(total) I replaced all 4. Will report back on drive-ability and FE.

PS: Just to be clear, all 4 of the plugs I removed today had the similar discoloration on one side of the plug as shown on the right-hand plug in the pictures. I just didn't turn the left-hand plug around to display it's discoloration.
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Old 09-03-2011, 11:54 AM   #23
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Re: VX getting lousy FE lately, what are the causes?

IMO the plugs look pretty dirty for only 4000miles. They should look like brand new.

I think your oil separator isn't doing its job or you have worn valve seals (real common for these engines with a few miles on them). There's a way to check this. Will explain later.

Also a great way to check to see if your plug wires are arcing at the boot is to put a single layer of masking tape around the hard part of the boot. If it arcs it will leave a burnt black mark that's really easy to see. One miss fire will leave a distinctive mark.

I would do a leak-down test and compression test to see where the engine is at health wise.
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Old 09-03-2011, 02:48 PM   #24
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Re: VX getting lousy FE lately, what are the causes?

Oil separator, is that like the breather chamber or what??? I'm new, yes.

Worn valve seals, after the previous plugs with only 20,000 prior didn't have these marks and only had carbon on the threads? The valve seals would go up in flames in only 4,000 miles?

I do not know how to perform either test, and would have to wait to pay a shop I know to do the tests. At 232,000 it passed a compression test(now at 254,000), but the mechanic that did this(he did so in passing) only tested the engine 'while warm' and not at full temp, implying it may 'fail' a compression test if performed again under full temp.

The plug wires have 24,000 miles on them(installed January of 2010), and have been pulled 3-4 times, I suppose that's worth a look, but all 4 wires arcing doesn't seem likely to me since they were brand new so recently. (unless one arcing would cause such a drastic misfire to be a problem resulting in all plugs appearing to have that strange burned mark on them). Either way, I haven't noticed severe misfire at any time, as far as I can tell.

Also, the clutch starting to go causes me to put more load on the engine(while riding the clutch longer to 'prevent' non-slippage of the disc, if that is what is happening to the clutch?) than I would under normal acceleration with a good clutch, not sure if that would impact plug appearance?

Yes, I too thought the plugs looked terrible for such a short period of time, especially compared to the ones with more mileage that were pulled previously.
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Old 09-03-2011, 03:10 PM   #25
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Re: VX getting lousy FE lately, what are the causes?

I'm interested in this too-
PGF, what is the tolerable compression for a VX? I know you're supposed to give 7 cranks or less, WOT, to test compression. Is it critical to be at full operating temp? As I recall, I tested mine on a cold engine.
Leak down I've heard of but never heard a good explanation of it.
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Old 09-03-2011, 04:19 PM   #26
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Re: VX getting lousy FE lately, what are the causes?

Quote:
Oil separator, is that like the breather chamber or what??? I'm new, yes.
Yep its the black box underneath the intake manifold that the PCV valve line connects to.

Quote:
Worn valve seals, after the previous plugs with only 20,000 prior didn't have these marks and only had carbon on the threads? The valve seals would go up in flames in only 4,000 miles?
OK if the other plugs looked good after 20k then something else is causing the poor plug readings.

Quote:
I do not know how to perform either test, and would have to wait to pay a shop I know to do the tests. At 232,000 it passed a compression test(now at 254,000), but the mechanic that did this(he did so in passing) only tested the engine 'while warm' and not at full temp, implying it may 'fail' a compression test if performed again under full temp.
The engine should be at operating temp to do a compression test. Also you should have the throttle wide open with the injectors disabled.

Quote:
The plug wires have 24,000 miles on them(installed January of 2010), and have been pulled 3-4 times, I suppose that's worth a look, but all 4 wires arcing doesn't seem likely to me since they were brand new so recently. (unless one arcing would cause such a drastic misfire to be a problem resulting in all plugs appearing to have that strange burned mark on them). Either way, I haven't noticed severe misfire at any time, as far as I can tell.
Sorry I was referring to when you said in another post that you thought you might be having a miss-fire.

Quote:
Yes, I too thought the plugs looked terrible for such a short period of time, especially compared to the ones with more mileage that were pulled previously
This is whats strange. Did you clean you EGR valve inlet lately. I have seen after cleaning the plugs will read dirty for a while.
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Old 09-03-2011, 05:05 PM   #27
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Re: VX getting lousy FE lately, what are the causes?

Quote:
PGF, what is the tolerable compression for a VX?
I don't have my Honda service manual with me now, but going by memory I think its around 170+ The main thing when doing a compression test is to know your tester. My Snap-on compression tester makes all my friends cry when we test their engines(it reads about 20psi lower then others) So the main thing is to make sure all cylinders are with in 10% of each other.

Quote:
I know you're supposed to give 7 cranks or less, WOT, to test compression. Is it critical to be at full operating temp? As I recall, I tested mine on a cold engine.
Yes its very critical to do the test at engine operating temperature. More so on race engines with loose piston to cylinder wall clearance.

Quote:
Leak down I've heard of but never heard a good explanation of it.
Leak down testing is wheres its at

Compression test are a fast reference to determine that something is wrong with the engine. Kinda like doing a blood pressure test. It tells us that your blood pressure is at a critical point but not whats causing it.

A Leak Down test tells us whats causing the low compression in a cylinder or cylinders. Kinda like the more advance medical test to pinpoint whats causing the high blood pressure.

So what I do after I know I have loss power on one of my race engines is do the compression test first. It gives me a quick reference of what cylinder is hurt.
Example: Number 4 cylinder has a compression reading of only 90psi compared to the other three that read around 165psi. So now I do the leak down test on number four only.

The Leak down process goes like this. Hook up the leak down tester to number four cylinder. This is down by threading a hose into the spark plug hole. You then put number four cylinder at TDC.

The other end of the tester is the hooked to a compressed air source via. "air compressor". The test will show you by its gauge what the leakage is in %. Anything over 3% for a stock engine is bad.

Now its time to determine where the leakage is at. If you hear air coming from the valve cover oil filling cap its rings or ring-lands. If air is coming from the exhaust pipe its a exhaust valve. If air is coming from the T/B its a intake valve. If air is coming from the adjacent cylinder spark plug hole its a head gasket etc. There's more to this but I think you get the idea.

One other thing I would like to add is this. On this site most of you aren't building race engines. But what I have found on a lot of stock engines with high mileage is the rings gum up and start sticking to the piston. This in turn will make you lose power and start consuming oil.

Engines like the VX are more prone to have this issue because of the dreaded EGR system in them. Do to lean burn they had to reduce NOX and did this by higher amounts of recirculating the exhaust gases. The EGR system of these engine was dirty and inferior to today's systems. This will cause the oil to breakdown early and loose its lubricating properties. In turn gum up the piston rings.

Hopefully this helps. I need to post this now before I screw up something and lose the entire post LOL
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Old 09-03-2011, 06:28 PM   #28
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Re: VX getting lousy FE lately, what are the causes?

^So, this leak down test is done with the engine off and attempting to determine if air is 'leaking' from various sources to identify a trouble spot

...but anything under 3% on the gauge, you're saying, is considered 'within tolerance' on stock setups anyway?

Yes, I did have the EGR + ports cleaned out a while ago now(9 months?), within the past year. Is it possible it had gone so long without servicing that they are needing servicing again?

I've been posting over at the BITOG forums learning about lubrication/apps etc, trying to extend out the oil change intervals on this VX. My insols were at 0.5% recently(considered just under the 'warning' level of 0.6%); that was a spike from my first UOA of 0.4%, I ran a HDEO combo with MMO(20% of the refill capacity/volume) for about 2,750 and it seemed to generate more gunk in the oil.

Currently, I have an Amsoil oil filter on there and I'm trying to see if that will help catch more of the crud that could have stayed behind after draining that oil.

I suppose I've got some cleanup going on in the engine, still, and it's caused me to hesitate extending the interval to date(longest so far has only been 5,000). I may have some ring related issues.

I may try a piston soak eventually(though I've used Amsoil's Power Foam twice now), and I hear Mobil1 is good at 'keeping' ring packs clean(though I don't know about actual cleanup compared to other oils). I have also considered taking Pennzoil up on their 'guarantee program' under another vehicle my parents own that would qualify for their rebate going on( http://pennzoilwarranty.com/our_warranty/) ...so, that'd give me a chance to run Ultra for 5,000 or so in an attempt to clean things out more. (for basically free, I have oil filters on hand and just have to pay postage for the rebate, ...maybe $2 out of pocket after rebate)...

Currently using Amsoil 0w30, but I have some High mileage oil(Valvoline MaxLife Full Synthetic) and was going to use that next summer. I could alternative try an idle engine flush before my next oil change as well.

It's possible the breather chamber needs a good once over. Is it easy to pull that off? Any o-ring/gaskets to replace? I believe it may have an o-ring??? I was actually going to pull it off the next time I remove my oil filter from underneath the car and see how it looks. Judging by how dirty my actual PCV valve was seated into the breather chamber(oil separator), ben(IIRC) had asked me to remove it when I had the chance.

PS: Sorry for the confusion, I should watch how I say things, but it could have misfired and I didn't realize anyway knowing my level of car 'expertise'.
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Old 09-03-2011, 06:53 PM   #29
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Re: VX getting lousy FE lately, what are the causes?

Quote:
Originally Posted by add|ct View Post
^So, this leak down test is done with the engine off and attempting to determine if air is 'leaking' from various sources to identify a trouble spot

...but anything under 3% on the gauge, you're saying, is considered 'within tolerance' on stock setups anyway?

Yes, I did have the EGR + ports cleaned out a while ago now(9 months?), within the past year. Is it possible it had gone so long without servicing that they are needing servicing again?

I've been posting over at the BITOG forums learning about lubrication/apps etc, trying to extend out the oil change intervals on this VX. My insols were at 0.5% recently(considered just under the 'warning' level of 0.6%); that was a spike from my first UOA of 0.4%, I ran a HDEO combo with MMO(20% of the refill capacity/volume) for about 2,750 and it seemed to generate more gunk in the oil.

Currently, I have an Amsoil oil filter on there and I'm trying to see if that will help catch more of the crud that could have stayed behind after draining that oil.

I suppose I've got some cleanup going on in the engine, still, and it's caused me to hesitate extending the interval to date(longest so far has only been 5,000). I may have some ring related issues.

I may try a piston soak eventually(though I've used Amsoil's Power Foam twice now), and I hear Mobil1 is good at 'keeping' ring packs clean(though I don't know about actual cleanup compared to other oils). I have also considered taking Pennzoil up on their 'guarantee program' under another vehicle my parents own that would qualify for their rebate going on( http://pennzoilwarranty.com/our_warranty/)...so, that'd give me a chance to run Ultra for 5,000 or so in an attempt to clean things out more.

Currently using Amsoil 0w30, but I have some High mileage oil(Valvoline MaxLife Full Synthetic) and was going to use that next summer. I could alternative trying an idle engine flush before my next oil change as well.

It's possibly the breather chamber needs a good once over. Is it easy to pull that off? Any o-ring/gaskets to replace? I believe it may have an o-ring??? I was actually going to pull it off the next time I remove my oil filter from underneath the car and see how it looks. Judging by how dirty my actual PCV valve was seated into the breather chamber(oil separator), ben(IIRC) had asked me to remove it when I had the chance.

PS: Sorry for the confusion, I should watch how I say things, but it could have misfired and I didn't realize anyway knowing my level of car 'expertise'.
I see your well educated in the oil testing part of the program, me not so much. Its something I plan on learning in the near future. I'm also very interested in a way to soak the ring pack to loosing up them. If you come across anything let me know.

The black box is very easy to remove. You will have to get to it from the bottom of the car. They do get gummed up and then they don't scrub the oil properly. I recommend letting it soak in carb cleaner for a day or to then blow it out really well.

Quote:
^So, this leak down test is done with the engine off and attempting to determine if air is 'leaking' from various sources to identify a trouble spot

...but anything under 3% on the gauge, you're saying, is considered 'within tolerance' on stock setups anyway?
Yes engine off with the cylinder being check set to TDC.

EDIT Yes there is a o-ring where it goes into the back of the engine block. I have seen them become very brittle and need replacing. But most of the time there re-usable.
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Old 09-03-2011, 07:06 PM   #30
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Re: VX getting lousy FE lately, what are the causes?

Interesting that another plug would allow more air to pass even though it's seated into the threads?

As far as piston soaking:

Kreen is a big hit on the other forums for now. It's encouraged to order the stuff by the quart opposed to larger quantities as gallons or larger containers charge a ton more for shipping(haz. mats.)

I'd get a couple quarts of the stuff and try that for your next soaking experiments(plugs out, soak and then manual crank you know)...it's sold by KanoLabs(relatively expensive, cheaper than AutoRx).

http://www.kanolabs.com/engCle.html

PS: I'll post pics of the box when I pull it. ...oh and definitely some parts cleaner would be worth it as a true soaking. If the box is still in tact no cracking etc, I'll just clean it up and be done, also will check the PCV valve again. Thanks for the help!
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