Varnish in Honda 3.5 VTEC

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How many times have we heard here that "varnish is only a cosmetic stain"? I was even told i had a fetish for believing it can be a nightmare for modern high tech engines.
Seeing as i have a 2005 Honda here with an all to common varnish/sludge issue that basically disables 3 cylinders when the VTEC valve sticks i decided to document it and share it here.

Here is the valve itself,we removed it earlier,cleaned the screen only and reinstalled.We ran Kreen through the engine and the valve did begin to move.It still looks bad but it is much better than before.

sam0063e.jpg


This is the small filter that gets clogged.This is very small and takes very little to stop the flow of oil.

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The solenoid that gets also stuck when varnished.

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The passages in the head.

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This is proof that varnish is anything but cosmetic in some if not most modern engines.Most modern engines use some sort of oil fed actuated valves or tensioners to perform different jobs,while the effects may not be as extreme as in this engine the varnish can definitely stick some important components.

This engine had documented 7500 mi OCI with a major brand of synthetic oil, (i will not disclose the brand as it maybe taken as a bash,it is not.The issue here is with the engine design)The PCV had been serviced.

With these engines the question has to be is 7500 to long?
The oil filter had gone into bypass and dumped a lot of junk into the passages.
More passage pics to follow,we will be doing a pan drop for inspection only and will post pics.
 
How many miles on this engine? Was 5w-20 used in this engine?
 
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Wow 7500mi OCIs with syn was not sufficient? Why would the filter go into bypass so soon? Any idea on filter brand or if they were left on for 15k at a time?
 
Wow, imagine the guys who blindly extend OCI's to 25,000+ miles or a year because the oil company said they could. Yikes!
 
I guess one could say that's not varnish, and more like serious build up. These Honda engines are way harder on oil than people have assumed - be the people Amsoil or BITOGians. I believe the major cause is fuel in the oil and fairly high combustion temperatures.

Just as a seat of the pants thing, my wife's 3.5 V6 comes up to temp, like NOW. The temperature stabilizes just fine, but it gets hot and gets hot quickly.
 
82K on this engine,soccer mom van,short trips around town but lots of them.Severe service at its worst.
Yes 5w-20 but after we get it cleaned up Mobil 1 ESP 5w-30 will be used,this oil is recommended for this engine in the rest of the world.Its obvious the oil didn't hold up well in this application.

Quote:
Wow 7500mi OCIs with syn was not sufficient? Why would the filter go into bypass so soon? Any idea on filter brand or if they were left on for 15k at a time?


Look at the following pictures and you decide for yourself if it was sufficient.Oil filter was changed every OCI with OEM Honda.As far as i can tell there were a lot of deposits and minor sludge deposits that probably clogged the small oil filter sending it into bypass.Varnish and particulate matter appear to be the main culprit here

Oil filter mount.

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Engine where mount bolts on.

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Gaskets.Note the new one has an extra filter added. It makes me wonder if Honda is trying to address this issue with modified parts without openly admitting there is an issue.

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Parts clean and ready to be reinstalled.

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Oil pan drop pics to follow over the weekend.
Not the areas the Kreen did mange to get through to are beginning to come clean.It did in fact get oil back into the valve and got it functioning again.
 
Hmmm. I have the same type of driving wife with the same engine, but a 2008. We got it with 28k already used. I changed the dealer bulk to PP 5w20 and was planning 7500 OCI's. Perhaps I should shorten to 6k? I don't mind if it prevents this junk from happening.
 
Originally Posted By: Pablo
I guess one could say that's not varnish, and more like serious build up. These Honda engines are way harder on oil than people have assumed - be the people Amsoil or BITOGians. I believe the major cause is fuel in the oil and fairly high combustion temperatures.

Just as a seat of the pants thing, my wife's 3.5 V6 comes up to temp, like NOW. The temperature stabilizes just fine, but it gets hot and gets hot quickly.



There is build up for sure but the amount of varnish is incredible.IMHO varnish is a precursor to the formation of sludge.Again that's just my opinion.

I have done work to a few of these engines in Germany for friends of mine that were using the ESP for 15,000 KM (9K mi) OCI and none showed this kind of build up.
Oil quality issues along with an engine design issue?
I don't know but i would like to find the answer.

After doing so many of these and Nissan VQ engines i have learned a lot about them and what makes them tick but there sure does seem to be some lube related issues with both that causes all sorts of strange engine codes.
On the Honda the engine will drop to 3 cylinders,throw misfire codes all over the place and act like a plugged cat basically undrivable.

I pulled the injectors out of this one not to long ago and ran them on my flow bench,all were tight with no leaker's and a all 6 had a nice spray pattern.Fuel dilution doesn't seem to be a major issue on this particular engine anyway.
 
I don't think the 20 grade oil was to blame here. I think a shorter OCI is the ticket. It is obvious the mfg suggested OCI is not working! Based on what you're saying it looks like a design flaw, plain and simple. I wonder if a pint of MMO for the last 1000 miles of the OCI would have helped? Or a yearly treatment of MMO for a shorter winter OCI? Or an annual treatment of Kreen would have helped? My bet is yes. Hindsight is 20/20.

Nice job cleaning up that baby! Great pictures and report, thanks for posting!
 
My brother had these identical issues also at the 80k mark.
I would definitely run a shorter OCI maybe even 5k with a high quality filter.
Keep an eye out in the oil filler,if it begins to look dark brownish in there shorten the OCI dramatically until its clean.
Its been my experience that once this stuff gets a hold in the engine its a very slippery slope.
 
This thread makes me a bit nervous - as I've been doing 10K OCIs on a vehicle that sees a similar type of service.

One question - Can a Blackstone UOA detect when the oil is in a state likely to begin the formation of varnish?

My first thought was TBN and Total Solids, but then I suspect Total Solids wouldn't go up appreciably until sludge would begin to form. I suspect varnish would begin to form well before that.
 
Trav,

There are zillions of these Odysseys on the road. They have a list of "pattern failures" but this one is NOT one of them. I follow dedicated forum for Odyssey regularly and to best of my knowledge I do not see this problem being reported often enough.

There is something unique about this particular sample.

- Vikas
 
Originally Posted By: btanchors
This thread makes me a bit nervous - as I've been doing 10K OCIs on a vehicle that sees a similar type of service.

One question - Can a Blackstone UOA detect when the oil is in a state likely to begin the formation of varnish?

My first thought was TBN and Total Solids, but then I suspect Total Solids wouldn't go up appreciably until sludge would begin to form. I suspect varnish would begin to form well before that.


I doubt a B_S report can detect varnish. It would have been interesting to see a lab report of the oil taken from that engine to see if anything was suspect, and if there is a way to detect varnish. I always viewed heavy varnish as a primer for sludge. Light staining or discoloration is not an issue. I always felt varnish was the signal to start cleanup before its to late. This just proves that. My bet is a UOA would have shown that oil to be OK for more use.
 
Vikas I should say this is the iVTEC engine not the standard VTEC.This was only used in the EX with Leather and the Touring model.
The 2005-2006 models seem to be effected most.I don't know when Honda started using the additional filter in the filter housing exactly but i have to assume it is in regular production.The original gasket number is no longer available nor is it even offered as an alternative.

This would prevent most of the failures by catching the offending particles before they can partially plug the VTEC screen and allow varnish to form to the degree it would eventually stop the valve from functioning properly.
As you can see the filter in the housing is twice the size of the VTEC one.In early engines this filter was not installed.

The owner this van didn't think his would be effected either until one day right out of the blue the VSA and CEL came on and the engine ran horribly.
As far as i can tell 80-100K is the zone.
I think you may start seeing more of this issue as more of these vans get into that mileage area.

Also the issue seems to be more with really extreme service not the ones that get a decent run regularly.
What i call the soccer mom syndrome.

*Cold start allowing the engine to idle while "warming the car up"
*Repeated endless short trips with mostly cold engine.
*Long OCI for severe service.
 
Originally Posted By: Dan55
Short trips are murder on any oil and when people are still advocating 3K or 3mos on changes, it makes sense.


I agree! I can only imagine what that soccer mom engine would look like if the DIY soccer dad decided to buy an extended drain oil and follow the recommended drain interval. Lets say he ran a primo extended drain oil for 1 year logging 15,000 miles. Twice the amount in the pictures but still well within the limits of this extended drain oils suggested interval. The pictures we are looking at would be pristine! Extended drains aren't for everyone or every application. Caution should always be used. JMO
 
This looks more like a thin layer of sludge, not varnish. To me, the definition of varnish is when the metal is discolored and there is nothing to wipe off. If you wipe something off and the metal is not discolored below, that is sludge, not varnish.
 
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