Hello everybody,
after a very long period of "Should I? Not now, maybe later.", I finally bought an EF Civic.

It is an American ED6 1990 model, which is a rarity here in Europe (it was imported from USA in 1994). It has 270.000 miles.

After two weeks of driving, I decided to ask some question about quirks I've seen so far as I'm preparing to do the initial service:

1. The car seems to be oil-hungry. The previous owner used 10W-40 oil. Based on the mileage and noticeable oil consumption, should I maybe switch to a thicker oil, e.g. 15W-50?
2. I've also seen that Honda's recommendation for transmission oil is also in the similar range (10W-40). Can the same type of oil be used both for engine and transmission? Or, do I need to be careful about GL4, GL5, and similar tags? (I know Miatas are very picky about it, not sure about Civics)
3. I should buy NGK BCPR6E-11 spark plugs, as recommended by the service manual, right?
4. I've been losing some coolant, but looking from above, I cannot spot any obvious leaks. Is there some "usual spot" where coolant leaks are more likely to happen?
5. What type (color) of coolant do you use?
6. I plan to lower the car. I know the usual recommendation is GC + Koni yellows, but I have no idea where I can buy that in EU (Buying from USA means I need to pay taxes and import fees, which makes the whole thing ~40% more expensive) and I'm not seeking for "absolute best, no matter the cost". I was thinking about buying Eibach springs which lower the car 30 mm (1.2"). Any recommendations for (budget) shocks for that drop?

Thank you in advance!

 

1. The car seems to be oil-hungry. The previous owner used 10W-40 oil. Based on the mileage and noticeable oil consumption, should I maybe switch to a thicker oil, e.g. 15W-50?
sure, whatever you think is necessary, but its just a bandaid to the real leaks and blowby issue. some seafoam, carb cleaner, and checking for leaking seals is helpful to start.

2. I've also seen that Honda's recommendation for transmission oil is also in the similar range (10W-40). Can the same type of oil be used both for engine and transmission? Or, do I need to be careful about GL4, GL5, and similar tags? (I know Miatas are very picky about it, not sure about Civics)
this is a big debate, ppl have different camps. i dont think a manual written 35 years ago is considering modern oils. i recommend honda MTF, they started making it after the CRX was sold, and has changed a few times. in my opinion, its only gotten better, regardless of however you characterize it. no issue with it running thin, its a good thing to me.

3. I should buy NGK BCPR6E-11 spark plugs, as recommended by the service manual, right?
sure.

4. I've been losing some coolant, but looking from above, I cannot spot any obvious leaks. Is there some "usual spot" where coolant leaks are more likely to happen?
headgasket obviously. is the exhaust sweet? one other typical place is actually the intake manifold gasket might have an internal leak, allowing it in the combustion chamber.

5. What type (color) of coolant do you use?
green.

6. I plan to lower the car. I know the usual recommendation is GC + Koni yellows, but I have no idea where I can buy that in EU (Buying from USA means I need to pay taxes and import fees, which makes the whole thing ~40% more expensive) and I'm not seeking for "absolute best, no matter the cost". I was thinking about buying Eibach springs which lower the car 30 mm (1.2"). Any recommendations for (budget) shocks for that drop?
eibach prokits and tokico blues of KYB AGX is fine. i miss tokico illuminas... Progress suspension (USA again) is good. Bilsteins run stiff.

 

I don't think these questions are really specific to an EF, but more so any civic from the era up until 2000-ish.

1. I'd stick with factory. 10-30 i believe is the factory rec for all 88-00 D and B motors
2. I only use Honda MTF on my 88-00 D and B transmissions.
3.Again, assuming the motor is internally unmodified, I'd go with factory recommendation.
4. Probably a blown head gastket. Especially if you don't see any leaks. Not really surprising for a car with almost 300k miles.
5. Shoot, at this point whatever is on sale... Or, again get factory fluid.
6. Aren't there a plethora of European shock makers KYB, Bilstein, H&R? If you're only lowering 1.2", which is a good choice IMO, than you should be fine with any off-the-shelf, performance shocks you can get your hands on. Koni's erally are nice though, especially with only a 1.2" drop.

I also have a 90 civic hatch in my garage, sitting next to my 96 Teg GSR. Love em both. I've got the Progressive CSII on my hatch. I prefer Koni/GC, but they are a little more expensive.

 

I to was losing small amounts of coolant and found when I took the timing cover off that the water pump was actually where it was coming from, I assume over time the bolts had backed off some causing the slight leak. Never left a drop , must have burnt off during driving or was just fanned out with everything spinning.
Stick with the NGK plugs, seems to run the best. Only others I have used is Bosch Iridium plugs that worked very well, anything else did not get the same resulrt.

 

Thank you guys for the replies so far!

What would be considered "normal" (or: acceptable) oil consumption on these cars/engines?

 

Maybe a quart per 4k miles. That would be on the high end for me, but it comes down to preference. If it's running well otherwise, than you are probably fine.

 

I got my ED7 with 230k on the clock with a D16A6, it burned about a quart between oil changes at first but got worse. So check the oil frequently, and pay attention to if/when you see smoke. Mine would smoke badly on deceleration.

In my case it was solved by re-ringing the pistons and ran great until I swapped it out at around 290k

 

Well ****.... I've added half a quart (maybe a bit less) when I was filling the gas, that was 300-something miles.

Are worn valve stem seals the first suspect? Anything else I should check/replace?
(I can cheaply get another D15B2, should I think of swapping the engine?)

 

You would want to figure out your coolant loss situation first. If it does end up being a head gasket, it will be better to fix the valve seals and/or piston rings at the same time.

Also make sure you know where your oil is going. If there are no severe visible leaks it is likely burning it. The easiest thing to replace first (relatively) would be the valve seals. They can be done without removing the head. Piston rings would be next.

Re: replacing the engine entirely, that may end up being less involving overall but with the age of these engines you may end up in the same situation again.

 

After the initial loss in the first days after I bought the car, it seems that coolant level is now stable.



Local mechanics are telling me replacing valve seals cannot be done without removing the head. Maybe I need to find some other mechanics


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I've googled a bit more my symptoms — rough idle, high oil consumption, hard engine start — and I've seen several articles pointing to a stuck open PCV valve.
I've tried pressing PCV hose while the engine was idling, and I didn't hear any clicking (not sure how loud that should be). Top part of the hose looked not very well seated so I removed it and then I saw this:



It was completely clogged.

Now I'm trying to find a new PCV valve, but no luck so far. Is `17130-PM3-003` the correct part number (the engine is D15B2)? Can I put some other part, maybe from a 5th or 6th generation Civic?

EDIT: Wait, is this in the photo (located on the intake manifold) the PCV valve? Because the top of it moves down on the slight press. I thought PCV valve is a plastic piece on the other side of that hose, down below, on the engine.

 

It's hard to tell from the angle. D15B2 engines look to have a metal PCV valve that screws into the intake manifold.

Certainly before jumping into any bigger projects make sure the PCV system is working properly. A clogged PCV could be driving oil out of seals elsewhere. Check the valve cover breather lines, PCV valve (once you find it, what you have in the picture looks like a PCV valve but I'm not familiar enough with D15B2s to be sure), and clean out the oil breather baffle on the back of the block.

I would not have expected yours to be so clogged up so thats a good catch!

 

Here is a photo from a different angle, it seems it really is this vertical metal thingy:






I went back to the car, planning to remove the PCV valve to see if it rattles, but I didn't have a long enough wrench so I couldn't get it loose. But I found deposits AGAIN, after zero miles since I cleaned it couple of hours earlier.
It didn't take long to find out where is this coming from — the hose:



So I definitely need a new hose (and a way to remove/install the bottom clamp - I've tried reaching it from above, but it is too narrow even for my small hand), and maybe/probably a new PCV valve.


Here is the current valve cleaned up as best as I could. Not sure if this is the correct top-most position or if it should be higher to be properly closed?

 

Looks better, take the valve off when you can and clean it out with solvent. The hose should go to the breather box, which is easier to deal with under the car.

Best of luck, hope this clears up your oil consumption.

 

Here are compression test results:

Dry test: 1st cyl: 95 psi, 2nd cyl: 100 psi, 3rd cyl: 105 psi, 4th cyl: 130 psi
Wet test: 1st cyl: 150 psi, 2nd cyl: 140 psi, 3rd cyl: 135 psi, 4th cyl: 140 psi

Higher numbers on wet test were expected, but I'm a bit surprised at the amount of difference (50% for the first cylinder). Does this big difference still mean worn piston rings, or is there (also) something else that might be problematic?

 

Here's a new question:

When I turn the key to ON position (before starting the car), from the right-front (ECU?) I always hear six loud beeps. Is this a normal behavior or an indication of something wrong?

EDIT: This one was easy! The passenger side seatbelt needs to be "connected", even if nobody is sitting there.