202 Holden Air Leak Issue

[MONARQ]

Okay, another question. Did you make sure your harmonic balancer hasn't slipped? The timing mark on the balancer won't line up with the mark on the timing cover properly if it has. That would mean that your ignition timing is not set correctly even with the timing light.

You can make sure that the mark lines up by taking the spark plug out on number one on the compression stroke, and putting a screwdriver in the hole and ensuring that the piston is on TDC. Then you can make a mark with a permanent texta or whiteout on the balancer where the timing cover mark says 0 btdc. THEN use the timing light again using your new mark as the reference point and see if it's any better.

Prior to this though, just try advancing the timing by loosening the bolt at the base of the distributor and twisting it a small amount at a time and see if you can get it to idle at all. I'd say that this is more than likely your problem. Larger cams like more initial advance in my experience

The end of the crankshaft has a 'key' for the harmonic balancer, so there is only one position this can be installed & this can not slip or move, due to the key. I think??
I will be trying your suggestion though, & re-time with timing light.
I set the distributor at about 6deg. (as it always was) & the mechanic increase this to about 12deg. but this didn't really help & still wont idle. When coming up to an intersection or slowing down, I have to use the accelerator & brake to try & stop it from stalling.

 

[EYY]

The end of the crankshaft has a 'key' for the harmonic balancer, so there is only one position this can be installed & this can not slip or move, due to the key. I think??
I will be trying your suggestion though, & re-time with timing light.
I set the distributor at about 6deg. (as it always was) & the mechanic increase this to about 12deg. but this still did not help & wont idle. When coming up to an intersection or slowing down, I have to use the accelerator & brake to try & stop it stalling.

The pulley is rubber mounted to the boss which has the keyway in it. The rubber breaks down over time and the outside 'ring' ends up slipping. It's a VERY common problem, even more common than those fiber gears turning to mush. Just give the dizzy a turn and see what it does (doesn't matter that you don't have a timing light at this stage, you just want it to idle). If it idles you've found your problem.

 

[MONARQ]

The pulley is rubber mounted to the boss which has the keyway in it. The rubber breaks down over time and the outside 'ring' ends up slipping. It's a VERY common problem, even more common than those fiber gears turning to mush. Just give the dizzy a turn and see what it does (doesn't matter that you don't have a timing light at this stage, you just want it to idle). If it idles you've found your problem.

Yes you are correct, the pulley is a two piece unit with rubber centre. And this rubber centre is perished & worn!
Thank you very much for your comments/suggestions!

 

[Big-Al]

EYY has a good point about the balancer. The outer ring can slip after time and cause inaccurate timing readings.

Still putting money on a bent valve though as this seems most likely and I've had it happen to me.

A compression test is the easiest way to check for a bent valve, I didn't mention it though as it can be misleading if compression is questionable already.
Visual inspection as I suggested is 100% dead set way to check but is more involved than a compression test.

 

[Dirbatua]

And the frustrating thing is, I didn't touch anything on the carb & manifold side of the engine during the rebuild (carb was covered in a sheet the whole time). And car run like a dream before the cam gear broke.

Any suggestions would be great help, im stuck!

So wait, you've installed a different cam shaft and you haven't re-tuned or re-jetted the carby to suit?

and i used to get carbon **** blocking up the vacuum lines on my old 202, would have to take the hoses off and get the **** outta em every 20,000km or so or the car would run like ass, not rev etc.

 

[EYY]

That's a pretty inaccurate way to find TDC. When degreeing a cam it requires a dial gauge to find the TDC.
Also if the balancer has timing marks, surely it would be keyed or something so it was accurately located on the crank?

You also need a degree wheel, but I was talking about finding a good starting point for setting the ignition timing. Totally agree with you though

 

[delcowizzid]

that cams a lot different than stock your gonna need to tweak the carby to run correctly its not as easy as fit the cam and go.did you run the cam in at 2000+rpm for 20 minutes to half an hour on first startup?.how much lifter preload does it have

 

[MONARQ]

So wait, you've installed a different cam shaft and you haven't re-tuned or re-jetted the carby to suit?

and i used to get carbon **** blocking up the vacuum lines on my old 202, would have to take the hoses off and get the **** outta em every 20,000km or so or the car would run like ass, not rev etc.

Hey,
Yea, the new cam is lumpier then the original one & I haven't touched the carb, apart from winding in the idle stop to try & get it to idle.
I have 'closed shut' all of the vacuum lines (one at a time) & doing this had not effect on how the car runs.
I will buy some new vacuum lines anyway just to be sure though.
Thank you for your feed back.

 

[the_boozer]

Big cam to be putting in an old motor does it have a vac leak or doesn't that cam make much vacuum at low revs? Are you shaw that cam can work with your current set up?
It looks pretty close to a crow 35666 we used to like them we'd change the carby, extractors recurve the distributor, high performance valve springs. While rebuilding the motor.
If its an auto will it need a high stall?

 

[MONARQ]

that cams a lot different than stock your gonna need to tweak the carby to run correctly its not as easy as fit the cam and go.did you run the cam in at 2000+rpm for 20 minutes to half an hour on first startup?.how much lifter preload does it have

Hey,
Thank you for your feed back!
Yes, the cam was run in at approx. 2200 revs for 30minutes on first start up.
I'm not sure how to 'tweak' the carby.... Haha I thought I did pretty well just getting the cam in! This may need to be done by a mechanic.
When the car is trying to idle, I put my hand over the carb butterflies & the rev's increase?? Suggesting it is still a vacuum issue?