Finally got the car running today, some crap in the carb had blocked a jet. Once carb cleaner had done it's job (I sprayed it in at 4pm) it burst into life. Quite a shock, since I wasn't expecting it to start.

Anyway, it makes a real racket when running. This engine has had new pistons and rings, feels smooth, revs quite nicely (although it feels tight, which is to be expected I guess), but is very noisy. Mixed in with some noisy tappets is a scraping noise, like metal on metal? I can't see anything that could be rubbing externally, presumably there's no way that the engine would turn over if I hadn't got the rings in properly ?

I thought I'd give the tappets a check and torque the headbolts. Trouble is, either the headnut wouldn't tighten or my torque wrench is faulty. It felt like I had some resistance, but nowhere near enough. I backed off one head nut, and found this:



Looks like I've pretty much knackered the washer... all the headnuts were the same, some resistance but never tightening up. Any ideas?

Thanks, Ben

Ben,
are you sure you've got all of the cylinder head studs wound into the crankcase good and tight?

It's normal for the brass washers to look rather 'second hand' after the head nuts have been properly torqued down.

Almost forgot, maybe try removing the plugs then winding the engine over with the handle to listen for unusual noises?

ken

Thanks Ken,

Hmm - no, I'm not sure at all. Is two nuts locked together the order of the day then?

Yep, standard M8 x 1.25 pitch, iirc.

ken

Check the plugs are the right type, that was my own massive facepalm moment following rebuild
very loud tapping noise

just read your post, the plugs should be b6hs, the ones you put in where b6eas? i was told sometime ago, cant remeber by who that the h is the length?

anyway hope you get the problem sorted

Scrapey noises on turning over ....its worth looking at the rear of the engine cowling to see if they have touched the flywheel

b7hs plugs

and id agree with ken, 2 nuts on the head studs and tighten down fully before you start

the head nut looks rather mashed make sure its not been dammaged internally before you have another go with the torque wrench.

Sean

Scraping metal to metal sound when running is usually flywheel touching the captive nut things on the cowlings, like Sean says.

cheers chaps.

Just checked, and there is indeed a captive nut hitting the flywheel, or at least about 1mm away from it. I thought I had fixed that when I put the tinware back on, but I guess it slipped back when I fitted the manifold. I'll fix that when I'm torquing the heads.

Ben

Ben,
looking at that picture again, I wonder if the socket you're using is deep enough?

A standard 12mm socket won't usually do the job as there's not enough engagement with the hexagon, especially if the socket's a 12 point type...

ken.