Rebuilt 1.6 engine, problems advice required.

Hello all,

Just looking for some advice from some experienced engine mechanics.

I purchased a GSi a while back, which had a full engine rebuild prior to me purchasing. I was running the engine in and it was running poor and misfiring and getting excessive oil vapour from the fitted oil catch can.

I did a compression test, which identified one cylinder at 0psi, one at 80psi and I believe the other two were around 175psi. I handed the car to my local mechanic who confirmed the compression test and sent the head away to a machine shop.

The machine shop identified two stem seals not seated / fitted correctly and reground valves, skimmed the head and handed me it back. The head was refitted by the garage and I was told to put around 1000 miles on the car and return to get the head bolts re-torqued. They also told me I would continue to get a lot of oil vapour from the catch can until the carbon builds up around the valves.

I?ve yet to check the compression (will do some point this week), but its definitely running on 4 cylinders now. I?ve put on around 700 miles and still getting excessive oil vapour from the catch can. When the cars at tickover the oil vapour is coming out the catch can filter like vapour out the exhaust pipe.

So I?m really looking for some advice as to if I?m doing the correct thing by putting on miles on in the hope the carbon builds up in the head. Reading in other forum some people state this builds up can take 4-5000 miles not 1000! (This is going to take me ages at the nova isn?t a daily driver) When this happens will this definitely reduce the blow by I?m getting into the crank and seeing the vapour coming from the catch van filter? Or should I be looking further down with the possibility of the rings not sealing or need the cylinders rehoned?

It?s driving me mad as the garage is just saying to drive it and it should sort it . Has anyone else had this kind of issue and when was the point where I should pull the trigger to tear it down in the hope of identifying the root cause?

Any help or advice appreciated, thanks

Mostly, running in is bullsh!t and has been for decades.

is it getting decent power? Or are you still tickling around in it?

i’ve literally only ever taken it easy for a day or so because if it’s going to show any faults, they’d be pretty immediate.

I’d be interested in any pics of the breather setup