Spyder VVC Autumn Projects

[sanzomat]

Well, I'm finally making some progress with my engine. It only took me 5 months to move it from the pallet to the shed so the progress since then is flying by comparison.
I got the head off a couple of weeks ago and have now managed to get a bit of port work done. It's my first go at this so was a bit nervous but wanted to give it a go and having looked at lots of pics and vids I thought "how hard can it be" Decided to go for a basic removal of the rough bits with just a small amount of metal taken away around the valve guides and bifurcation. The valve guides were chipped with some biggish chunks missing, especially on the inlets. No sign of where the bits had gone or any damage from them having rattled around in the combustion chamber so I wonder if they were chipped while being installed. Whatever, the pics I'd seen of peoples porting projects had all shown the guides ground back to the alli so that what I did too. Here are a few before and after pics. Not sure how much benefit it will give but it was quite fun having a go.

Exhaust - before: (I'd given the right hand valve a bit of lapping before taking this as this is the cylinder that was down on compression. Seemed to lap up okay so all will be lapped as the next job.


Exhaust - after:


Inlet - before, note chipped valve guides:


Inlet - after:


Exhaust Port - before:

And after:


Inlet port - before:

And after:

[Iancider]

Good work.

I guess the valve guides were chipped on assembly.  Perhaps tapped in out of true.

Ian

[Moleman]

Nice work mate. If you need any little bits shot basted we have a little shot blaster in work that I can get done for you.
We also have a little rust cleaning solution tank. 

[sanzomat]

Finally felt well enough to venture out into the shed. I was thinking I really should give back the tools I've borrowed (valve spring compressors and compression gauge from Bri and torque wrench from Dave B) so I thought I'd give the engine a quick compression test now the head is back on so I can can return the gauge. I hadn't yet put back on the cam ladder, cams, pulleys, belts etc. I thought there's no risk of valves touching pistons if the valves are all closed. Just turning the engine by hand with a socket on the main cranckshaft pulley.

I was rather concerned to see that the compression readings were all crap and started to have a bit of a panic thinking what I might have done wrong. I'd spent bloody ages lapping those valves!

Then it struck me that as all the valves are staying closed it won't be able to suck in any air to compress, so it will be just sucking a vacuum then letting it back to atmospheric pressure again each stroke! Doh! Maybe I'm still not well enough to be re-assembing the engine!

Anyway, I thought it wouldn't hurt to do a dry run so I dropped in the cams/ladder and put on the pulleys with the old belts and tensioner. Its actually quite hard getting the 2nd belt (that drives the 2nd pair of the four VVC inlet cams) timed up as there is no tensioner so you have to offer the pulley up to the end of the cam with the belt on it and when the timing marks are all lined up one of the inlets is opening so it keeps wanting to turn due to the valve spring pushing on the cam. Kept getting it one tooth out so it was good to practice before doing the final go with the new belts.

Anyway, with the valves opening and closing the compression seems fine, well into the green even with just a slow hand crank. Now to take those bits back off again and re-assemble with sealant on the cam ladder and thread lock on the pulley bolts.

[Iancider]

Looking forward to the result!

Santa needs you!

Ian