Engine install after rebuild + lots of questions

wehey

wehey

Ex. Club Member
i installed the rebuilt 1.3 today and it seems to be running well apart from an oil leak from the crankshaft pulley seal.

Before the questions, the engine internals are stock apart from a 1mm head skim to raise the compression.

So I got it all warmed up and went for a spin then checked the timing with a strobe. It was at 0 degrees so I went to alter it and the max it would advance to was 10 degrees.

So I set it there and went out for a drive. I noticed it was pinking, so went home and set it to 5 degree which seemed to sort it.

Next I checked the compression and was very suprised

All cylinders the same.

So the questions.
I've never used a strobe before. Do you set the timing with the engine on tickover?
Why couldn't I adjust to 15 degrees? Was this because I have used the strobe incorrectly
The compression seems very high to me. Is this what I would expect from a 1 mm head skim?
 
the ecu uses spark timing as a last resort to stabilise the idle wehey, so you need to lock it into base idle mode (as described in haynes) or else use a data lead and software (with the strobe)
 
frank said:
the ecu uses spark timing as a last resort to stabilise the idle wehey, so you need to lock it into base idle mode (as described in haynes) or else use a data lead and software (with the strobe)
Click to expand...
Sorry to sound dumb but what do you mean by "base idle mode"
 
if the idle screw is set too low, the ecu will advance the timing to stop the engine stalling.
so if you try to set the dizzy timing with a strobe while that is happening the base timing will be incorrect.
so you have to remove the tps and blip the throttle for the ecu to lock into base timing mode (then the ecu will hold the timing at a stable 15 deg btdc for you to set it with the strobe)
another way (my prefered way) is to use the data lead and lappy to see what the ecu is running, then i set the dizzy/strobe to the same setting :)
 
Ah yeah that makes sense now.
So disconnect the TPS lead, blip the throttle a few times then set the timing with the strobe.

So would that explain why I could only set it as high as 10 degrees and no further?

Also do the compression figures look normal?
 
yes, then set the idle at about 650 (i,m guessing the idle will stumble when you remove the tps)
and i would have expected 200+ with a 1mm skim and 1.3 cams personally (i would test the gauge against a tyre gauge)
 
I've just had a look at the Haynes and have realised that when I fitted the lower chain I didn't line up the dots and links as u should.
Could the idler sprocket be a tooth out? I can't get my head around whether it would throw out the cam timing a smidgen ?
 
unless the crank and idler sprocket stayed at exactly the same angle before & after fitting the chains, which I highly doubt, forgetting to sync the crank & idler sprocket together through the chain links means there's a high chance that the upper chain driving the two cams also isn't synced with the lower chain therefore the inlet/exh cam timing might be well offset and since the dizzy runs off the exh cam, that'll be well off too.

three ways to fix the timing.
- either remove the head & lower chain cover and realign the whole timing chain in or outside the bay,
- disconnect the upper timing chain and spin the crank several times until the coloured link in the lower timing chain lines up with the dot on the idler sprocket and then fit the upper chain matching the dots on the idler and cams,
- or if it was franks way, he'd prob just set the crank to tdc and judge the cams angle by eye or how many links the cam dots should be relative to a known locating point.
 
Thanks for the help Polly. You have confirmed what I expected and explains the dizzy timing issues I have. What a dumb ass eh.

The the thing is that I don't see how rotating the crank (with the top chain off) will magically correct the bottom chain. I would have thought that if the idle sprocket and chain are misaligned that they won't ever sync up again.

I can't remember off the top of my head but (with the top chain off and idler sprocket bolt removed) is there enough slack in the bottom chain to rotate the idler sprocket whilst the chain remains stationary?
 
you would have to turn the cams so that 4 valves are half open wehey (for piston/valve clearance) and i think you would have to turn the crank many times to get the dots to line up.
i often position that idler so that it advances the cams a bit (to compensate for chain wear, rather than line the dots up) :)
 
Last edited:
So what's the best way to tackle this?
Is it possible to remove the lower chain cover with the engine in the bay?
 
lower chain is a right mission, just check where the 12 o,clock tooth on the idler is at tdc, and if you need to advance or retard the cams, remove a cam sprocket and turn the engine a turn or two till the 12 o,clock cam tooth is where you need it (it,ll sit in a different position each time you turn it)
 
frank said:
you would have to turn the cams so that 4 valves are half open wehey (for piston/valve clearance) and i think you would have to turn the crank many times to get the dots to line up.
i often position that idler so that it advances the cams a bit (to compensate for chain wear, rather than line the dots up) :)
Click to expand...

I think its 38 times you'd have to rotate it all to get them back lined up Frank!
 
The timing is definitely out so I was planning on disconnecting the upper chain, then rotating the crank to TDC a few times until the idler is its correct position.
So which of the two positions in the pic above is correct?
 
the CG should be at 12,oclock iirc wehey, and the dots will line up every 720 deg (but the chain links will take many turns before they align)
 
Thanks. I'm not concerned with the links. Just as long as the idler teeth are in the correct positions
 
here,s the lobe position pic wehey (cyls 2 and 3 pointing at the side of the bolts)

as cam.JPG
 
So I have had a look at the timing today and it appears that the idler was 180 degrees out.
So I rotated the crank 360 so that the idler was as below and timed up the cams but I'm sure it doesn't look quite right?
What do you think
The exhaust looks advanced to me?
 
Last edited:
Ok, I have thought about this some more and I think (correct me if I'm wrong) that i have fecked it.
Looking at the idler sprocket there are 36 teeth on the larger sprocket and 23 on the smaller, so there are only a few possible ways that the teeth will be properly aligned as in the pic.
So for every 360 degree rotation of the crank the idler rotates 180 degrees and as I have the idler in an incorrect position in relation to the crank it won't ever be corrctect just by rotating the crank.

I can't imaging it will be possible to unbolt the idler and rotate it into the correct position with the crank remaining at TDC?
 
wehey said:
So I have had a look at the timing today and it appears that the idler was 180 degrees out.
So I rotated the crank 360 so that the idler was as below and timed up the cams but I'm sure it doesn't look quite right?
What do you think
The exhaust looks advanced to me?
Click to expand...


thats exactly where mine are set nowadays wehey, both slightly advanced :)
 
frank said:
thats exactly where mine are set nowadays wehey, both slightly advanced :)
Click to expand...
hmmmmm, so before I rotated the crank 360 and the idler 180 and reset it would I have been running retarded? Which could explain the high compression and lack of power?
 
frank said:
too advanced previously in theory mate, that would explain the high comp and pinking
Click to expand...
So just bolt it back together and see how it goes?
Is it possible to rotate the idler with the engine as it is or is there not enough slack in the bottom chain?
 
Right it's all back together. I took it out for a spin and it's definitely better than before but was still pinking.

So I unplugged the TPS and checked the timing. It's was waaaaaay advanced, off the end of the scale by miles. So I turned the dizzy to bring it back but with the dizzy against its stops I could only get it down to approx 18 BTDC.

So tightened it back up and went out for another run. It was better still but I'm still not happy. It pulled well but I was expecting more esp considering the other changes I have made to the engine. So I jumped in the red 1.3 which is completely bog standard and went out for a spin. Tbh it felt similar, if not quicker than the silver facelift.

So I think I will pull the motor and get it set up properly. It may well not make a difference but if I dont try I will never know.
 
Update:
I slotted the cam sprockets in the end and repositioned the cams as they should be.
This allowed me to set the dizzy timing correctly at last :)

It goes well but i guess the standard exhaust is holding it back a fair bit.
 
frank said:
if the idle screw is set too low, the ecu will advance the timing to stop the engine stalling.
so if you try to set the dizzy timing with a strobe while that is happening the base timing will be incorrect.
so you have to remove the tps and blip the throttle for the ecu to lock into base timing mode (then the ecu will hold the timing at a stable 15 deg btdc for you to set it with the strobe)
another way (my prefered way) is to use the data lead and lappy to see what the ecu is running, then i set the dizzy/strobe to the same setting :)
Click to expand...

I have just downloaded ECU talk and tried it for the 1st time :)
When I diconnect the TPS it reads 18 BTDC and when the TPS is plugged in it reads 3 BTDC. Does this sound about right?
 
wehey said:
I have just downloaded ECU talk and tried it for the 1st time :)
When I diconnect the TPS it reads 18 BTDC and when the TPS is plugged in it reads 3 BTDC. Does this sound about right?
Click to expand...
are you using a strobe to set the dizzy wehey ?
 
Oops, slight error, the throttle cable didn't have enough slack. So now it's slack I'm getting 15 with the TPS unplugged.

Yes Frank I'm setting it with the strobe
 
wehey said:
Oops, slight error, the throttle cable didn't have enough slack. So now it's slack I'm getting 15 with the TPS unplugged.

Yes Frank I'm setting it with the strobe
Click to expand...
and if you raise the rpm the strobe and screen dial move up and down together ?
 
wehey said:
Yes they do. I was just wondering of it was normal for the timing to drop down to 4 once the TPS is plugged back in?
Video below
Click to expand...
nah, it only ran 4 deg because the idle was too high mate, if you had adjusted the idle screw it would advance to 15 on its own
 
I have done all of that tho Frank.

Slackened off throttle cable
Disconnected TPS
Set idle speed to 625
Adjusted dizzy timing to match consult @ 15 degrees
Plugged TPS back in
Adjusted idle to 750

Consult now reads 4 BTDC ?
In must be ok because its drives fine
 
its using the timing to control the idle wehey (like mine does because i have no idle control valve) you need to drop the idle down so that the ecu is running 15 deg
the dizzy is synced to the ecu now so dont worry :)
 
1 or 2 turns in on the idle screw and blip the throttle and it should idle at 15 :) it might be because your idle control valve is fully open or fully shut, and needs setting (or seized maybe ?)
 

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