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After completing engine rebuild, car did not run normal. I am having misfire on cylinder 1 and 3 of my EJ25 SOHC. There is also knock noise from 1 or 3's side. Changing spark plugs did not help however I stopped there because I suspect I did not align the right side cam correctly. Attached picture shows how I aligned the right side cam sprocket. For some reason the dealership guys decided to leave 2 marks on cam after replacing the timing belt a year or so ago. I did not take pictures either prior to belt removal during the rebuild. Rookie mistake.. As you can see the slotted mark is not in top position and I am guessing that is what is causing the misfire and possible knock noise. If this is true does that mean that my valves are interfering and possible damaged now? FYI I have aligned slotted marks of the crank and left side sprockets to top position.

Thank you for help.
 

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I suspect I did not align the right side cam correctly. Attached picture shows how I aligned the right side cam sprocket. For some reason the dealership guys decided to leave 2 marks on cam after replacing the timing belt a year or so ago. .
It really doesn't matter how many paint marks are on the cam. The engine is timed when you have the crank notch lined up with the mark in the case and likewise for the cams: notches lined up with the marks on the heads.

Maybe the TB is off by 1-2 ribs? Turn the crank to the notch and check the cams for their notch alignment. Eliminate that part first. Looked at the pic again, and if you timed it the way it is pictured, definitely off. Looks to me like the timing notch is 3 ribs from the mark on the head (glare makes it tough to see)
 

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^^^^ what he said


find the tooth count for your engine, search on-line. good triple check for timing.
 

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According to that picture, your cam timing is off by 5-6 teeth. You should align the timing marks by the small line cast into the pulley, not by paint marks nor arrows.

Since the phase 2 EJ25 has very little tolerance for jumped time, you probably have bent a few valves at this point. A leak down test will tell you what sort of trouble you're in.

Chances are the dealership did not align the motor before removing the t-belt and just marked the then-current position of the cam gears for some backup.
 

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Discussion Starter #5
Thank you guys for fast response and help so far.

Now I am resenting the dealership guys for leaving unnecessary marks on cam sprocket. But I know I should have done my homework better.

If valves bent, that is a new head gasket and possibly the whole cylinder head down the drain. Sigh..

I don't have a leak tester nor compressor so I would like to fix the timing on the cam and run again for now. If valve bent, what symptoms should I look for when running again?
 

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It really doesn't matter how many paint marks are on the cam. The engine is timed when you have the crank notch lined up with the mark in the case and likewise for the cams: notches lined up with the marks on the heads.

The only way this will go sideways is if you turn the crank 1 turn, then things would be off 180 deg. Given the car runs, this isn't the case.

Maybe the TB is off by 1-2 ribs? Turn the crank to the notch and check the cams for their notch alignment. Eliminate that part first. Looked at the pic again, and if you timed it the way it is pictured, definitely off. Looks to me like the timing notch is 3 ribs from the mark on the head (glare makes it tough to see)
I'm curious what you mean by turning the crank one turn and being 180 deg out?

If the crank gear mark aligns with the mark on the crank position sensor holder, and you do one revolution and the crank gear mark aligns again, its exactly the same.
 

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Thank you guys for fast response and help so far.

Now I am resenting the dealership guys for leaving unnecessary marks on cam sprocket. But I know I should have done my homework better.

If valves bent, that is a new head gasket and possibly the whole cylinder head down the drain. Sigh..

I don't have a leak tester nor compressor so I would like to fix the timing on the cam and run again for now. If valve bent, what symptoms should I look for when running again?
Symptoms of lower compression in a cylinder (but not total loss of compression) is a slightly rocking engine.
I had a few cars with around 110 comp in one cylinder and the car ran fine and had decent power but the engine had a rock to it at idle, and would throw miss fire codes. Not a rough idle, just the engine would rock.
 

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Also I've had quite a few subaru's with blown timing belts that the valves survived.
How I test if the valves are bent,
1. align the crank gear mark (this insures the pistons will be clear of the valves)
2. put the cams in the unloaded position (where you have free play in the cams either way)
3. I grab the cam gears and flick the gear back and forth as fast and hard as I can, if there is a clicking sound in the valve train it is because the valves are bent and not fully seating, causing the valve lash to be way beyond spec. If the valves are fully seated it will not make any noise, since the lash is to tight to allow a clicking.
I've used this method on at least 15 cars and if there was no clicking sound the car ran fine. If it had a clicking noise, I pulled the heads and the valves were bent.
 

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Chances are the dealership did not align the motor before removing the t-belt and just marked the then-current position of the cam gears for some backup.
Yikes.... not aligning the timing marks sounds like a scary practice to me. I wouldn't surprise me with some of the shortcuts I have seen ..... do you suppose they actually do this? I guess if it ends up in time after they are finished, that's what counts? :|

Timing a Subaru SOHC is pretty easy with the belt markings and only having three timing marks. I don't mark them. I just did a four cam GM V-6 that has three cam chains and nine timing marks to align. I definitely put paint marks those on every time.
 

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I'm curious what you mean by turning the crank one turn and being 180 deg out?

If the crank gear mark aligns with the mark on the crank position sensor holder, and you do one revolution and the crank gear mark aligns again, its exactly the same.
Good point and catch. I was clearly thinking incorrectly there and not sure what was on my mind. Possibly thinking cams....
 

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Discussion Starter #11
Oh I just noticed more replies on this thread. Thank you guys.

A little update:

I re-aligned all timing marks and ran again. Power was normal and no misfire at all. I have attached some pictures of cam timing before and after. Maybe they come handy for someone else in future. Also I have attached some OBD II snapshots. Not sure if the info displayed useful at all.

I am not sure to be honest if I have bent valves. If clearance is very tight, I must have. Because I did run the car with the wrong cam timing for a few days while trying to de-bug the problem.

Aside from that, the car sounds a bit diesel-y now. Possible piston slap because I used after market pistons? I don't know.
 

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A little update:

I re-aligned all timing marks and ran again. Power was normal and no misfire at all. I have attached some pictures of cam timing before and after. Maybe they come handy for someone else in future.
Glad to hear things are better/good now. At least this was a cheap lesson learned! :grin2:
 

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Hahah I know! Whew!

Aside note: overall it was pretty fun this project. Now I want to do more hahah. It would be nice to play with a DOHC engine. I will need to save for this though lol.
 

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one - thanx for getting back to the thread with the pics.
 
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