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HELP! New head gaskets, now engine missfires.

Posted: Sun Apr 10, 2011 11:37 am
by Gruntus
OK!

so, i have just installed a VRS kit (inc head gaskets) and a new timing belt kit (tensioner ect) and finally got it all back together yesterday and the bastard doesn't want to run right.

the best i can do is max the timing advance and get 3 cyls firing,this made me think maybe my base timing was off, so i pulled all the timing cover off again and checked the base timing, all marks line up as they should (little hole is cam gears line up with slots in timing cover, and crank dowel directly up) as far as i know this is correct.

the head gaskets got replaced because it was leaking between the combustion chamber of no.1 cylinder and one of the cooling jackets, thus heating up the coolant very quick.

i have tried moving the leads around to different positions on the dizzy and the best i can get is 3 cyls, most of the time its on 2 :S

i have checked all vaccum lines and im starting to think something else is wrong.

to clarify i have spark at all cylinders and yet runs like poo.

tomorrow i will try borrow the compression tester from work to check compression across the board, but until then does any one have any ideas?

any help would be much appreciated.

Thankyou

Posted: Sun Apr 10, 2011 11:59 am
by TOONGA
1. What engine are we dealing with? ea82, EJ hybrid, EJ injected?

2. is the motor carby run or computerised?

TOONGA

Posted: Sun Apr 10, 2011 2:38 pm
by Gruntus
Carbie EA82

Posted: Sun Apr 10, 2011 3:30 pm
by discopotato03
Two hickups sometimes here .

Flat four firing order is 1324 unlike an inline 4 which is 1342 .

People sometimes use the ignition timing reference marks on the flywheel instead of the 3 lines close together a quarter of a turn past the ignition timing marks .
Easy way to tell is to line the correct marks up on the cam pulleys (need only outer covers off) and then look through the hole in the flywheel housing to see if the three parallel close spaced lines are bisected by the housing pointer .

Another issue from memory is not rotating the crankshaft 360 degrees after fitting the inner belt and before fitting the outer one .
The reason you do this is because one complete four stroke cycle is 720 degrees or two complete crankshaft revolutions . The right bank is phased 180 degrees around from the left bank meaning a piston rising on one side is a piston falling on the other side .

A .

Posted: Sun Apr 10, 2011 5:31 pm
by Gruntus
discopotato03 wrote:Two hickups sometimes here .

Another issue from memory is not rotating the crankshaft 360 degrees after fitting the inner belt and before fitting the outer one .
The reason you do this is because one complete four stroke cycle is 720 degrees or two complete crankshaft revolutions . The right bank is phased 180 degrees around from the left bank meaning a piston rising on one side is a piston falling on the other side .

A .
Can anyone verify this?
i just thought put it back on where you take it off, you know to avoid bending valves ect.

Posted: Sun Apr 10, 2011 6:52 pm
by El_Freddo
Gruntus wrote:Can anyone verify this?
i just thought put it back on where you take it off, you know to avoid bending valves ect.
As what Disco has said. You DO NOT line up both cams at the same time when doing the timing belt on the EA82 - install one belt as per instructions, rotate crankshaft once then install the other side as per instructions.

EA82s are non interference engines so there's no issues with bending valves. :D

This should sort out your issues - I bet it feels completely gutless at the moment.

Cheers

Bennie

Posted: Sun Apr 10, 2011 10:49 pm
by Gruntus
havent actually driven it since new head gaskets, because its been missing so bad i havent been keen.

so this will most probably be my problem? seeing as it was running smooth before?

Posted: Mon Apr 11, 2011 1:01 am
by steptoe
please, post up your firing order, where #1 lead is on dizzy cap in relation to firewall, should be closest to firewall, and compressions. New spark plugs and leads too ?

The first EA82 timing belts I replaced were done without turning engine over, simply marked old belts and reference ponts, counted teeth, marked new belts same, counted more teeth and was fine.

Posted: Mon Apr 11, 2011 9:02 am
by Gruntus
i have tried multiple firing orders, started with usual 1-3-4-2 then saw its ment to be 1-3-2-4 and still no good, spark plugs are about 1000k's old and leads are all still good (checked continuity) and yes number one is closest to the fire wall.

Posted: Mon Apr 11, 2011 10:12 am
by TOONGA
sounds like you will need to reset the timing belts

TOONGA

Posted: Mon Apr 11, 2011 11:54 am
by RSR 555
TOONGA wrote:sounds like you will need to reset the timing belts

TOONGA
+1 :)

I'd say you need to remove the timing belts and start again. The first step is to set the flywheel up to the correct position. This is 3 small lines after the TDC (timing light marks) on the flywheel. You'll need to setup to the centre of the 3 marks, then you'll need to move the camshaft pulley wheels to their correct positions. Now I'm sure 1 side points to the 12 o'clock mark and the other to the 6 o'clock mark. In the manual (going off memory here so could be a little sketchy) it has something like set the inner timing belt at 12 o'clock then rotate the engine 360deg(thus making the mark now at 6 o'clock) then set the outer timing belt to 12 o'clock. But as long as you have 1 dot at the top and 1 dot at the bottom then you'll be fine. If you haven't removed (turning it is ok) the dizzy then you should be fine there too. Firing order is 1-3-2-4 and the dizzy rotates in a anti-clockwise direction. If you have this all back together and it doesn't start then try moving all the leads on the cap around by 2 spots because it just means you are on the exhaust stroke and not the firing stroke.

Hope this helps and makes sense?

Cheers,
Paul

Posted: Mon Apr 11, 2011 1:19 pm
by discopotato03
Yes , have to forget all the inline four cylinder principles with flat fours .
Try to look at flat 4 engines as two 2 cylinder ones laying in opposite directions but sharing the same crankshaft . You set each cam belt for its own 2 cylinder engine .

Flat engines are about packaging , they are generally half a cylinder longer than half their number of cylinders which makes them shorter than inline ones and lower in height .
The downside is that the block or cases has to split to get the crankshaft in/out and there has to be twice as many heads and cam drives unless they have pushrods like an EA81 .

I think Subaru could have made better pushrod EA81 heads in the mid 80's and not bothered with SOHC per bank EA82s .
But , overhead cams were all the rage then so they went down the road of a cambox conversion and belt driven camshafts . A bit more work on those twin carb EA81 heads would have been a lot easier with I reckon no emissions/consumption penalty .

Posted: Mon Apr 11, 2011 1:31 pm
by Gruntus
Thanks to everyone that replied!
i reset the timing like disco potato said and it fired up beautifully first time.
runs unbelievably smooth now, with a bit of extra KW to boot.

once again thats to everyone who posted for the help, could have done it without ya's.