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Power loss after changing T-belts


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Hello all,

My left timing belt recently broke why i was driving on my 91 Subaru Loyale with the EA82

I replaced both timing belts (they were done about 60K miles ago along with the water pump) following the EA82 T-Belt replacement guide by MilesFox

Once i got it put back together i started it up, it seemed to start and idle fine and i moved it out of the shop.

Next day i went to go to work, and let it warm up for a few mins, when i got in it to go i noticed it seemed kinda sluggish... I thought it was just because i wasn't used to driving it after driving a car that had quite a bit more power. After pulling out of the drive way, i started to accelerate and thats when i figured out something was really wrong with it.

At first i manged to get it into 3rd gear before it didn't have the power to go any faster, but the more it warmed up the weaker it got. After turning around about 1K feet down the road, i could only drive it back in first gear.

The Right cylinders seem to be running rough and backfiring. At first i figured i had my timing off by a bit, but i've double and triple checked it and had friends check it too, and it is perfectly on.

Has anyone else ever had anything like this happen? Any ideas?

Thanks in advance!

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It is important to check on 3 items.  Since you followed Miles' video.....I am gonna assume the first 2 are correct.

 

1)....You used the center of the 3 hash marks for belt alignment, not the TDC marks....correct?

 

2)....You did rotate the engine once between installing the belts....correct?  This should leave each Cam's "dot" mark 180 from eachother.

 

This is the one I suspect......

 

3)  The plastic covers distort over time.....moveing the marks slightly.  The drivers side espescially, it's easy to put the belt a tooth off trying to get it to point at the marks int eh plastic covers......but you can somewhat ignore them.....and place each "dot" excactly vertical when aligning......straight up and down......even if it's not pointing quite at the notch......

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Thanks for the replys!

I just redid them (lined them up with the marks on the covers again....) and it's still doing the same thing.

Yes, Gloyale, I did 1 and 2 perfectly. I'll try it again though without lining them up with the covers. It looks like they should line up pretty well with the crack between the valve covers and the heads?

1 tooth off can really have that much of an impact eh? I checked the temps on the exhaust. and the right side is much cooler then the left. Plus the right side will backfire every once in a while so it's the right side for sure that is the problem.

Anyways, i'll keep y'all updated!

Thanks so much!

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The line up notch is same line as the join of cam box on head - nice engineers :)

 

Recently done two sets, and once sort of broke the rule of never turn crank backwards and the dizzy side belt managed to skip a tooth even though I let the tensioner do its job!

 

Once both belts are on and correctly tensioned, I rotate a few turns more to ensure all markscontinue to line up and tensions are still good. Were you able to measure the torque on the cam drive cogs in anti clockwise with torque wrench? I had to use guess work as my torque wrench is damagable if I use ratchet in anti clock.

 

I lost the ease to rev to 6000,6500 once new belts were on, but power came back down rev range - maybe by 500rpm. Got my best fuel economy since doing them

 

Oh, I know it sounds absurd, but on ausub a member onsold his EA82T, that later did a belt and n.o. mechanic claimed valve had hit pistons, possibly due to a few shaves too much ?

 

Comp test coming up ?

Edited by jono
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silverback, my timing marks are that picture perfectly if i put my cams at that angle....

My marks line up with the top and bottom notches in the covers, and from what i can tell they are straight up and down, and they are in line with the grove between the valve covers, and the heads.

I can go take some pics and put them up if y'all think it'd be helpful.

I never turned it backwards, and I do the same thing of turning through a few times by hand to make sure they stay lined up...

No, i'm not able to measure my torque on the cams...

I don't see how my valves could have gotten damaged at all, as the side that is not running properly is the right side, and the left belt is the one that broke.

Edited by 206airmail
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I just checked everything again. My timing marks on my cam sprockets line up perfectly with the gap between the valve covers and the heads, and with the notches on the back covers.

It has been quite a while since i replaced my cap and rotor (new plugs and wires a few K ago) Someone was saying that the cap can get a crack in it and that could cause it to miss a couple of cylinders? It does not appear to be cracked at all...

Any other ideas as to what could cause this? I've had a couple of other people look at it and they all say it looks perfect to them too.

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Just to clarify......the picture posted shows the belt position in with the crank at TDC on compression #1.

 

They should be rotated (90 at the crank=45 of the Cam) to observe and set the Cam timing w/3 hash marks.

 

Also.....what you are calling Right and left are confusing......Are you  speaking looking into the engine bay from the front? or of the Car?........

 

Generally we refer to the directions of the car.....like sitting int eh drivers seat in the USA that's the "left" side of the car even though looking from up front it's on your right.

 

It is your left or right belt that broke?

 

All I can say is it's very easy to be a tooth off of excactly vertical w/ the crank and 180 from eachother.

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Yes, Left is the drivers side.

I've been lining everything up with the pointer in the flywheel hole pointing to the middle of the 3 hash marks. I checked it all again the timing holes are exactly vertical on both sides, and they are 180 deg opposite of each other... I'm going to go pull my valve covers off and see if i can see anything off in there....... I honestly am out of ideas... I had another friend come over this morning, and asked him to read the guide and double check me (without any input from me), and he said it looked perfect to him too.

I honestly have never been this stumped before, and I'm not totally new to the mechanic world, I've worked in aircraft mechanic shops, grew up doing mechanics with my dad..... I've never came across something like this...

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180 degree out dizzy engines don't even start do they ?

 

This one started and ran nice until operating temp, so I can see why you are stumped - especially after so many checks, so, I think I asked if you had a chance to check compression ...sort of takes you back to step one diagnostics so you can at least add good comp to the baffling mystery.

Sounds like someone dropped some coincidence while you were in there :(

 

It is a carby set up ?

 

Tell you what stumps me (for the moment) is how you can say it is the right side ( ie non dizzy side / cyl's 1 & 3) that is back firing ?

 

You got dual carb or exhaust ?

 

I admire your temperature taking diagnostic :)

 

Or another thought, when you have the three amigoes lll lined up from memory it is the non dizzy side that has the tiny hole in cam wheel that lines up with timing case mark/top of head - your rotor button is pointing towards firewall and #1 post inside dizzy - silly question because you said it started and idled nice

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Hi all, It is an EA82 SPFI engine. I have not yet checked compression, but i will when i get a chance. When the engine backfires it really sounds like it is on the right side (cyl 1 and 3)

I also checked my ignition timing yesterday with a light, and #1 cyl was firing at the correct time (or at least getting spark)

Edited by 206airmail
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another question .... did the leads or cap come off at any time ? and firing order is still 1 3 2 4 as you have #1 firing at correct time. I have done 3 1 2 4 before on an engine assembly in cramped conditions on the floor under a bench :) Think I have done 1 3 4 2 as well :)

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I just had the same thing happen to me, replaced the belts according to milesFoxs video. The first two times I ended up with the same results as yours. My solution is a bit trial and error, but if remember correctly, I aligned my pass side cam gear about a half a tooth counter-clockwise, rather than directly lined up. Worked like a charm. Maybe give it a shot on the drivers side? A bit off one direction, then the other.

Edited by ystrdyisgone
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you may have the plug wires crossed on the 1.3 side. firing order is 1-3-2-4. Rotation is counter clockwise. #1 on the cap is just to the right of the clip/screw on the rear of the cap. Cylinder arrangement is:

3 4

1 2

 

as long as you had not removed the disty, the disty timing should still be correct. An aftermarket cap may have mis marked positions as some cross reference with weird isuzu makes.

 

Please see the you tube videos if that will help clarify. (any 'milesfox', 'ea82' or 'subaru timing belt' search should find them.

 

There will be some slack in the cam belt that may make the notch on the cam be off by half a mark. be sure that the taught side of the belt is true withthe cam, and when you take the slack out and tighten the tensioner, it is ok if the cam moves to the left of the mark, as long as the belt does not skip.

 

Double check your plug wires order, especially if you get popping and backfires out of the throttle body.

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Double check your plug wires order, especially if you get popping and backfires out of the throttle body.

Just to add, I was a tooth off on one side and was getting backfires out the carb. Seems like it may just be as simple as being a tooth off.

 

And a bit more detail: My drivers side idler seized and shredded that belt, so I was simply doing an R&R and had the same issues, I didn't touch the disty, plug wires, etc..

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Well, I moved the right belt around some, and it seems to run quite a bit better with the right cam about 1.5 teeth to the left of where it's suppose to be (if your sitting in the drivers seat) Still backfires a bit though when it's idling and you have to step on the gas

I have the SPFI 1.8, not the carb

Edited by 206airmail
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I just had a thought.   Did you take the crank pulleys off?

 

There is a front and a back one......And if you mixed them up it can lead to this problem where you end up a half tooth off somewhere.  They are offset to eachother slightly.

 

If you have em back off to check.....the "back" one or drivers side has a bit of a depression on the back, whereas the "Front" passenger side one is flat both sides.

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No, the only pulley i took off was the v-belt pulley.

So I moved the belt around a little bit more, got it in a spot where the car was running just perfect, no backfiring, good rpm increase when you gave it gas. Then I tensioned the belt, and started it and let it warm up for a while, and as it warmed up it started running worse and worse until now it is back at the point where it backfires really bad, and really super slow rpm increase when you give it gas. If you just push the gas all the way down, it almost kills it.

Is it possible that my belt is stretching out somehow as it warms up and throwing the valve timing off? A defective belt maybe? Or is there something else that could be contributing to it?

One other thing, my radiator fluid level is wayyy down, like a couple inches below the neck of the radiator. I flushed it last year, and wasn't sure that I got it refilled all the way (didn't seem to take as much as it should have) but i checked it pretty regularly over the next few months and it was always full. I have not checked it recently, so don't know if this is something new or... It's not bubbling at all, is it possible for my head gasket to have gone out but the fluid not be bubbling? any other way to check? Does not really seem to be putting excess water out my tail pipe, although there might be slightly more then normal, but not by hardly anything.

I'm just really stumped...

I had it running just perfect, and then it just started running worse and worse... Any ideas?

Thanks in advance!

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hi,

  the coolent temp sensor for the fi system,   and it's connections,   they give symptoms similar to what you have described,   any chance you missed connecting it or knocked a wire loose and not notice.

  they do cause trouble like your symptoms, especially as the temp comes up,  and are known to give trouble on these cars.

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