Hi all,

Edit Update:The first page(s) of posts is old, current issue(s)/challenge(s) are on the last page(s) of the thread. First page(s) may be skipped if you are not after a long winded entertaining (maybe) storyline.

I already have a thread for my wifes car, the 93 Hatchback with the D15B carb transplant, so I thought maybe I should make a thread specifically for my car.

It's a 1995 Canadian EH2 hatchback with manual moonroof/sunroof (always thought sunroof opens completely while moonroof only flips up, FSM seems to indicate otherwise). Anyways, I had a D15B7 dropped in to refresh the aging D15B7 that was knocking mildly when I bought the car. I bought the used motor off the shelf and their test showed 200 PSI on all 4 cylinders at the time. Didn't smoke but has always consumed a bit of oil.

Oh and forgot, the only mods on the stock D15B7 motor is the noise maker mods of 2.25" 4-2-1 Header -> High flow 2.75" in Cat 2.5" out -> 2.5 Inch cat back exhaust and an AEM Short Ram CARB compliant intake tube with Dryflow air filter. So she breaths well and exhausts well and sounds like a lot more than she really is.

I've driven the motor pretty hard over the last year and half to two years. Anywyas, this last winter I notice she's starting to smoke. Not at start up or idle or take off or decel. Only at high RPM. Typically around 4500-5000 rpm.

Tonight I took her into the parking garage and slowly raised the RPM to 5000+ and sure enough there was a nice cloud behind her. The part that gets me is it is predominately whitish looking. I don't really see much blue hue in it (smoke hung around in the basement for me to get a good look). Also it didn't seem to have an oil smell nor did it smell sweet. Nor am I losing coolant. She is eating a significant amount of oil though. I believe I'm beyond Honda spec of 1 liter every 1500 Kilometers. Also of note, she puffs thin white smoke for a handful of seconds even after the idle drops back down to 650-750 idle range. I can pounce the gas up to 5500+ rpm, let off, walk to the back of the car, see the cloud in the air and see light grey/white puffing from the tailpipe for a short duration of idle before it disappears.

And lastly, I have a fair amount of oil residue on the bottom of the PCV valve. It still rattles so doesn't appear to be stuck open or closed but definitely shows passing oil through it. I recently replaced the grommet and o-ring on the breather box. Recently as in last fall/winter. Not sure if there is an easy way to rule out vacuum suction of oil through the PCV system without purchasing an additional oil catch can.

I'm hoping to do a compression test this weekend with my wifes help. I'm hoping my tester is still working. I seemed to have trashed the check valve in it and so I just put a check valve from a tire into it. Hoping the spring is not too stiff to let the cylinder push air into it. Anyways, once I have the numbers I'll post them up.

Figured I'd get a head start on the think tank side of things. I would think if it was from the typical ring wear (high rpm only smoking) it would be more blue in hue and smell of burnt oil, instead it smells kind fuelish and stinky exhaust like.

I think I might just undo the spring bolts and check that the honeycomb is still intact on my high flow cat. I have bottomed out pretty hard a couple of times and so thinking a malfunctioning cat might make visible exhaust in certain circumstances.

Anyways, if anyone has some theories that fits the scenario, feel free to share. Will post up compression numbers once I have them to continue the diagnostics.

Oh and I'm still getting solid fuel economy and power seems pretty much the same for summer weather on the short ram intake.

 

You could have a few causes of oil loss, all contributing to the overall high oil consumption going on with this old engine.

Any leaks at all? Is the oil pan totally dry?

These engines are old, so unless you're replaced the valve stem seals, they could be leaking oil directly into the intake tract while under vacuum (basically normal driving with the throttle plate slightly open). Very common oil consumption issue with these motors from the '90s.

I would go ahead and replace the PCV valve, just to rule it out.

The smoke could be from running rich at high rpm. You're description of the smoke's smell indicates that. Checking out the cat isn't a bad idea.
And how much smoke are we talking about? Sounds like a cloud coming out of the tail pipe.

The compression test may indicate low compression, but if it doesn't that's not an indication that the oil control rings are still healthy.
Also, when you pull the plugs for the comp. test, peer down the holes with a flashlight and see if the piston tops are shiny. This is a dead give-away sign of a leaky head gasket.

 

Thanks for the reply Bryan.

I didn't get to the compression test today, that's on the books for tomorrow. I'll also try to get some pics of the under belly so you can see the oil pan is dry. The rear main was replaced when the engine was installed as was the cam seal and the lower spark tower seals. Had all this done with the transfer of the new timing belt, new water pump and had a new clutch installed all at the same time. He reported the front main seal was still in good shape so didn't change that.

Needed the car back in a day or two so as to not lose much work so I paid my Honda Tech friend a grand to do all the work instead of me fumbling through it all without all the proper tools etc etc.

I understand valve seals but was under the impression those tend to show smoke during deceleration and take off from idle which I don't get. I usually get it under load, near wide open throttle and typically starting around the 4000+ rpm mark. Would bad seals work okay until high vacuum situations and then suck oil in like no tomorrow?

Also in the parking garage it didn't dissipate at all for a long time where steam on these hot dry days should. I'll still be checking the piston tops when I have the plugs out tomorrow and report back. Also think I may have to replace plugs.

The amount of smoke is what bothers me, it means a crap load of oil as dense white it is and not smelling sweet. It's like the smoke I got when I did the wet test a year ago. Took a good 5 minutes to burn off and it was plumes and plumes of white smoke.

Today when I shot the video below, I did see a little blue hue in it as it thinned out moving across the street.

As thick as the smoke is, I'm wondering if a broken ring would cause that much oil to pass.

I guess the compression test will tell more.

Please enjoy my polluting video below.



Found this snippet on Snap-On compression tester manual. Have to wait till the weekend is over before I can get a hold of our local Snap On guy for a set of six one way valves. Using a tire valve would give me improper results by the looks of it.

 

Mine does the same thing, the rings are good there's minimal leakage in the cylinders.

I think your problem has to do with high oil pressure, I bet its some internal gaskets inside of the head. Probably the valve stem seals, when the oil pressure raises it goes straight down the valves into the combustion chamber. Prolly from being beat or just high mileage

 

internal gaskets inside of the head? lol. looks just like the beginning of a blown headgasket. coolant pools in the combustion chamber and is then burned off. rent/buy a block tester. it does not take much coolant to make a smokeshow.

 

dunno man mine didnt have leakage out of the radiator and it did smoke like that. I'm not saying it cant be the head gasket I'm just relating his experience to mine. It doesn't really look like oil smoke as much as mine did

 

Looks like steam not oil smoke to me. When you pull the plugs, I'll bet you at least one is shiny steam cleaned.


It's not usually a big cause of oil burning. My point is that often there are a few small issues (high crankcase pressure, poor oil control, leaks etc) that contribute to the overall consumption. From what you said it sounds like this motor is in good shape and not leaking externally.

At part throttle when cruising vacuum is high enough to suck oil through failing valve guide seals.

 

Here is an update, will still be following up with a compression test sometime this week once I have the one way check valves from snap-on so that I can repar my compression tester.

Anyways, I pulled the plugs tonight and found an issue in #4. Beginnings of oil fouled and by the looks it's coming from the top the way the oil is all the way up in the thread of the plug and a bit more on one side of the plug for ash. I believe a valve guide or two are shot on #4 which in turn have really finished up the valve stem seals, and is probably why I've been consuming oil for quite some time.

The rings seem to be okay even though #4 was near BDC when I added a syringe full of Marvel Mystery Oil.

It's not steam. May look like it but it's high amounts of oil into the chamber. Steam dissipates quickly. This smoke in the parking garage lasts for several minutes like more than 5 minutes and can be smelled hours later. The garage smelled bad over 3 hours later when I went to check on the MMO in the cylinders. #1 had passed all the oil by the rings (it's near TDC) while #2 and #3 have a little bit to seep past the rings (they are somewhere in the middle) and #4 looked to be still full after 4 hours (near BDC). Which makes sense, the widest part of the cylinder on an aged motor is the top so is the loosest.

Anyways, I'll still be doing a compression test to verify the rings are still in decent shape.

Oh and none of the cylinders are shiny, all black with carbon as was the plugs. So with all the evidence, no shiny cylinders or plugs, no coolant loss, No mix of oil in coolant or coolant in oil, and the smoke hangs around for eternity, I am confident I can rule out head gasket. Here are the plugs for your viewing pleasure. In order #1, #2, #3 and then #4 last.






So now I'm looking at the Y8 head that I know is in good working order that my tech buddy gave me.

Either way I'm going to have to take the head off the block for repair. And being I wish to do a mini-me somewhere down the road, it makes sense to me to at least semi refresh the known good working Y8 head with new seals and use that as my head.

Upon looking at these specs though, it looks like the Y8's primary lobe is a bit smaller than the B7 but not by much. I'm thinking the impact in power shouldn't be all that noticeable. And then the head will already be installed once I get a chipped ECU with base maps and can go have it tuned. I don't really know what the longer exhaust will do though. I don't know enough about engine theory to really have a grasp of the impact it will have.





Thoughts anyone?

@Bryan, Forgot to mention, my pan has been dry but I have a new wet spot for the front main. Last summer and fall it was all dry. Saturday I stopped at the shop and walked under the car to see it is mostly dry but the front main has a drip on it. So I knew my consumption wasn't leaks and my recent valve cover leak wouldn't be enough to account for the amount of oil loss I've had for a long time now.

Also, what is the trick to figure out Compression Ratio with different HG thicknesses? (3 layer MLS vs 4 layer MLS)

 

TL; DR:

Appears to be bad valve guides/seals on D15B7. Requires head pull to fix.

Can a D16Y8 head be run as a replacement without vtec on the D15B7 ECU until wiring, chipped ecu and tuning can be done? (Specs for both cam lobes above this post)

 

I called it, h8rs gonna h8.

there's a tool to pull the springs off and change the guide seals without removing the head. I dunno where to get em tho, I want one incase my d16z6 head gasket isn't bad.

if you drive it without raising the oil pressure the leakage shouldn't really break anything for a long time

 

As bad as it is, it's more than likely more than just the seals. Just replacing the seals is probably only going to be a very short term fix. Valve guides themselves need to be fixed more than likely.

I'm just wondering if I can get a head start (excuse the pun) on my mini-me without doing the full 9 yards until I can scrape up more cash for the rest of it (chip, tune etc).

If I can't I have another B7 head that was recently gone over from my last motor that I can easily do up the seals and put on. And it has the D16A6 springs to boot being later year B7 head.

But if I can save myself from paying for new head gasket, new intake gasket and new exhaust gasket again just to do the mini-me that would save me over a hundred bucks.

But if not, then it's not a big deal. Just thinking ahead on my plans is all.

 

I dont remember if you need an adjustable cam gear to run the y8 head. And I can't think of anything else you need but I haven't really looked too far into mini-me head swaps.

 

You can. If you put any vtec head on it make sure you remove the oil control jet from the block, on the firewall side in between cylinders 2 and 3.

 

Thank you nub, I suspected as much but wanted a more experience opinion of the idea.

Your reminder brings up another question I've had for quite some time. Is there problems if that oil control jet is NOT replaced in the case of the original B7 head being put back onto the block later on down the road i.e. drop in oil pressure?

 

I don't have any experience with one being left out with a non vtec head and OBD0 or 1 block except a Y7 head on a B7 block. On 96-00 SOHC D's the oil control orifice is in the head on all versions. 95 and older, only the vtec heads had the control orifice in the head, all others were in the block.

These oiling systems are crank main priority, the head is secondary. The cam journals and rocker shafts are pressurized, everything else is "splash lubed".

Picture the control orifice like this:The oiling system is your houshold water hose, the control orifice is your thunb. What happens when you have water running through the hose and try to block it off with your thumb?

Flow and pressure have an inverse relationship. When one goes up the other goes down.

 

Shouldn't this require a vtec oil pump as well or is the b7 oil pump good enough? Any specs on that?

 

Vtec this, vtec that. There's alot of misunderstanding of what it is and what it takes to function.

For example, the D15B7 (non vtec), D15Z1 (vtec-e) and D16Z6 (vtec) use the same oil pump.

The Z6 is an odd ball when it comes to the distributor strictly having to do with its mounting ears. All other D series distributors will bolt to other heads and function minus differences in plug configuration and OBD0 not being compatible with OBD1 and 2 ecu's.

Take it to OBD2, the Y5, Y7 and Y8 all use the same oil pump (vtec-e, non vtec and vtec). The Y7 and Y8 use the same distributor with the Y5 being an odd ball Hitachi...but the Y5 and Y8 share the same head casting and distributor mounting pattern.

It really has more to do with the cam, rockers and ecu.

 

not to mention the y7 block is damn near identical to the y8. y7/y8 cam gear, belt for head. you will have a bump in compression as well.

 

Now I understand why it needs to be pulled. Would be double restricted reducing flow even further.

I get the feeling that oil jet is for the pressurized part of the head (cam journals and rocker shafts), more pressure required to pressurize the small spaces and since it's small spaces, doesn't need as much flow.

Logic would dictate that double controlled or no control would be detrimental in the long run. Double reducing flow too much and no control reducing pressure too much to be effective.

Gonna look at my unknown quality Y8 head and see how the control orifice is in it for that oil conduit. Might be interesting if it can be removed from there and effectively do the same thing as removing it from the block. I'm doubtful but will be interesting to look at.

Your explanations are always welcomed nub, I sincerely appreciate them in every thread I find them in, not just my own.

A little update with the car. I got a hold of my local snap-on guy and he has the compression tester repair kits (3 o-rings and 3 one way valves) for 8 bucks so I will be meeting up with him Wednesday, Thursday or Friday. Tuesday he's in a different city.

Also of note, I put a new plug into #4 and it didn't smoke as bad today when I ripped on it. Still did blow smoke but nothing like the video.

Tonight when I pulled the plugs for day 2 of the MMO treatment, #4 had signs of the beginnings of fouling. And it was mainly on one side of the plug. So tonight I'm going to clean up the plug, and I marked one side of the nut portion with a permanent marker. This way I can see the orientation of the plug before I pull it tomorrow and be able to decipher which side of the head is leaking oil.

Less than 6 months ago, the plugs looked good when I swapped them out and my concern was only #2 being a little darker than the others so running a little cooler. Now it's all about that oil leaking into #4.

Also of note, the MMO in one treatment has already made a difference in the piston tops except #4, it's pretty bad with carbon understandably. Quite impressed with how well it works and understand it's effectiveness in unsticking rings.

Here is the photos of #4 in one day of driving and only two short high rev bursts of making the car smoke just for a moment:





My next post will be with the compression numbers later this week or sometime this weekend.

Thanks again to everyone, you all make H-T the great resource it is.

 

Got the new check valve for my compression tester and first round on a hot engine I forgot to open the throttle. Results from 4->1 was 210,210,210,205. Took one pic of the 210.


So after I realized my stupidity, I parked the car in the parkade and setup to do it again, this time with WOT Results from 4->1 was 220,220,220,215 which can be seen in the following pics. #1 dropped closer to 210 by the time I got the phone to shoot the shot (gloved hands). The other three held a touch better.





Being a D15B7, the salvage yard got 200 on all four and I'm still getting 220-215 with my cheap gauge, I didn't think much change would happen with a wet test plus I didn't want to smoke out the parkade with oil smoke.

The symptoms of of WOT high rpm smoke doesn't fit valve seals. I did 3 days MMO treatment and it doesn't smoke like it did in the video. It stopped that after replacing the fouled plug.

Also the plugs are looking a nice tan. Still smokes a bit on WOT.

All my research says the rings are on the way out, the compression holding pretty well and being that high seems to indicate if it is rings, it's the oil control rings.

The real curve ball is most the ash is on one side of the plug (intake side I learned from marking the one plug). I originally thought that if the rings were not scraping oil it would coat the plug on all sides. One idea did occur to me, the rod pulls down on the exhaust side and pushes up on the intake side. Maybe there is just enough side force to scrape the exhaust side and opening up the intake side on the down stroke, then the rod pushes towards the intake side then scraping the oil straight up the cylinder wall up onto the plug on the intake side.

I just can't seem to believe it's valve related being it doesn't act anything like valve seals. No smoke on take off unless I slam WOT and it waits until close to 5K rpm before you see the smoke. No smoke on deceleration and no smoke idling.

Wife followed me and said she did see a little smoke when we were cruising down the highway, not a lot just a little. I might have been giving a little more by going to 3/4 throttle while already moving at a good clip but pushing gently to pick up a little more speed. Smoked so little couldn't see it in my rear view. WOT I see it in the rear view regardless of my speed.

The ash on one side of the plug(s) just throws me for a loop.

Still not sure how the motor could have such high compression when the crank, rods, rocker arms and head look so clean, no staining or build up so would indicate it shouldn't have a large carbon buildup either.

Also I realized the PCV valve goes into runner #2 and that is why that plug is always a little darker than the others but not fouled so I don't think it's getting a detrimental amount of oil from there.

Is there anyplace in the head that can crack that would let oil into a cylinder? If not I guess it just means my oil control rings are weak and that is causing my heavier consumption and smoking at high rpm's.

Engine still sounds solid, not sure what the long term affects of bad control rings are besides oil burning.

 

Mine had closer to 250 compression, except cyl 3 chipped valve. Tons of smoke at WOT, except mine was black/blue more than white.

after removing the head I found literally 1/8th inch hard nasty carbon built up on the valve faces. Lots of carbon on the back of the face/stem too.

I never considered oil control rings, though. If majestic ever finally delivers my parts I'll finally(!) put this POS back together and see if it still smokes with 100% new gaskets on the head.

and also my spark plugs were coated with oil one day after replacing them. Just cranking the car for the compression test coated em with oil

 

My plugs are now burning clean. After day 2 of 3 of the MMO treatment I wasn't getting oil on #4 anymore. Another indication that maybe it's the control rings.

 

Seems like you were right with the original idea that your rings are sad. What are your plans? Repair, replace, ignore ?

 

Stuck oil ring probably. Had that issue with my b20 and also used mmo and no more burning oil.

 

long term issues- mainly exhaust related. you will go thru plugs faster, but you will also burn out oxygen sensors/ ruin your cat from the oil.