Engine rebuild

Hi

Just finished rebuilding the engine in my Y reg golf 1600, after replacing all the bearings, gaskets and piston rings using rings from euro parts I went to start the car up and it did not start. So checked the basics fuel and spark. And then done acompression check. No compression at all valve clearence ok head all torqued down,timing ok. somehow recon its the rings but did check the free gap was ok. Anyone have any ideas or passed experience. :dontknow:

Cheers

Craig

Check that there is a gap between the cam followers and cam to ensure the valves are seating properly.

Check the cam timing is setup correctly.

Put a teaspoon of oil down each bore and do your compression check again.  If you get a little compression then suspect the rings.

let us know how you get on.

Took your advice on puting some oil down the bores and doing the compression test again only got about 3 p.s.i of pressure which isnt much.
So now I have decided to buy the origanl rings from vw.
But there on back order so have to wait a few weeks.
seems every part for the mk1's are either back order or obsolete.

I'd have though that you'd get more than that with oil down the bores - more like 50psi

Make sure you have eliminated other issues like valve seating and timing.  If the valves are not seating properly - only needs to be a small amount you will get poor compression (likely to be worse on ony one cyl though).  Valve timing could be way out - again check the timing before you rip the engine apart.

Have already checked valve timing with feeler gauges, and marks are spot on. I also took the sump off and turned engine by hand can here gass escaping through bottom end.
Only thing I can think is the piston rings are the wrong type
did notice new piston ring are stepped instead of flat would this make a diffrents, also have heard there are diffrent pistons K.S and mahle according to haynes manual maybe these have diffrent ring thickness.

As a side thought, when you put the rings in, did you make sure that the gaps in the rings weren't in line with each other ? I know it sounds daft, but if they are then this will also allow compression to escape passed the rings and give low compression.

Also when you put the new rings in, was the block rebored or given a light hone to help bed the new rings in?

All the piston rings were gapped at 120 degree intervals. Although the engine was not rebored it was honed out with a glaze buster, done by a engineering company.

Double and triple check the valve timing - check that the piston is at TDC (look through the spark plug hole) when both valves are closed (both lobes pointing up).

Rings are not normally an issue unless they are completely the wrong size - thickness should be less of an issue

Sounds tricky this one (!)

If the rings are 'wrong' and not sealing, presumably they'd allow oil past which would foul the spark plugs, so might be worth seeing if that's the case first. The rings would have to be a really poor fit for the car not to fire at all IMO. More likely a timing problem as Crazyquiff said. Is it noisy when you turn the engine over ?  Are you using fresh plugs ?

Good luck with it,

Mark

Have checked the timing by taking spark plug one out and turnig to t.d.c.
Then lined up the bottom pulley with the mark on timing cover. I als lined the top end up so both number one cam lobes are up and lined the mark up on the sprocket.
Have now taken the head off valves o.k(not bent)and took one of the pistons out.
Did notice that the top two rings seem a bit loose and slide left to right just by tilting the piston, is this right. :dontknow:
There is also no oil coming up past the piston.

If the piston is out of the engine then the rings should be a nice fit in the grooves.  They should easily slide sideways.

Did you use a ring compressor when you fitted the pistons to the block?

I'm a bit stumped on this one - even really badly worn/broken rings would give you about 20psi on a compression test.  That's why I keep on about valves etc

Sure you're doing the comp test right? Or your meter isn't faulty?