Race Engine Forum UK

Hi all,

I'll start this thread as my project. I have an Alfa Romeo 33 1.7 QV 1988 Series 2 with twin Dellorto carbs 40DRLA.

A tappet sound started in Feb and just got worse. Tried changing oils, Liqui Moly products etc to eliminate the possibility of block oil passages.

It was time to rip it apart and see what's going on inside. It was not nice to see the damage.

I've always been mechanically minded but never tackled such a big project before so it's a learning curve for me.

I have plenty of pictures. I will start adding a few each day. Also of course some of my car.

Regards

cylinder cross hatch pattern.
smooth feel to them as I run my finger down them. Maybe too smooth. After de-glazing do you feel a slightly rough feel to the surface?
Still a good pattern showing.
Your opinions would be appreciated.

It's not what you see, or feel with your finger, when it comes to honing for new rings. It's about a very precise structure of the cylinder walls that is required for the new rings to bed in properly. This structure can really only be viewed when using microscopes and such. Every time you change piston rings, you need to re-create that precise finish, or the new rings will not bed in properly on the cylinder walls and you're worse off than re-using the old rings.

Having done a few of these myself, judging by your pictures, I'd say you have 5 of 8 tappets worn irregularly. That means that at least 5 of the lobes on your cams are worn. You can tell by the circular patterns on top of the tappets. Those are very typical for Alfa hydraulic tappets. I guess it's the same for other brands, but I haven't seen any of those myself so it may be different.

Thanks Whizzman.

Yes very true, quite a few tappets worn and lobes.
Have new cams and 8 new tappets, new oil seals, valves, gaskets and also new gears for the oil pump.
I imagine the oil pump sucked up bits of that lobe and pitted the gears.

Also my ex-mechanic put new tappets in the car 2 1/2 years ago but left the old cams in. No wonder the tappets only lasted a short time. He was the owner of the care at that time.

Flexi-Hone being shipped!

some more pics:

Great car, I love the Boxer engine what a fantastic sound, I have had a few Alfa Suds but never a 33. My Sud had a 33 1.7 16v engine and outboard front brakes too, the sound was like music to me and I would regularly find myself going for pointless drives just so I could hear the engine!
Were many Old Alfas imported to Uruguay?

Thanks mitch strada.

yes they have a beautiful addictive sound that just makes you drive them hard and the overun is sweet. (unless you have broken tappets!!)
Also the induction sound if you can release it is just sweet also.
I've opened up my airbox a little to release the induction sound more.

Foam socks are not really suited for our climate here. We have too much dirt and dusty roads.
K&N panel filter is fitted.

Not so many suds/sprints/33's.
Only a handful of 33's in good condition. mine is well known here.
My brother-in-law has a sud 1981 4 door 1.5 super and his father has a sprint for racing.

Great cars but in good climates due to their awful rust problems.

Nice - but more time your end should be devoted to reading about basic engine overhauling - and less to dressing and painting.

G

GC - this dressing was done due to extra time available in the house and not being able to get to the garage.
Wife and son responsibilities/issues.

Not because I was neglecting engine overhauling basics.

Regards

Don't feel got-at. There is a method to everything I write here.

I said it because having coached you here from the beginning I think that undertaking an engine overhaul with so little basic engine knowledge is a bad thing and again, with your evident interest, I think you should get into some good books on this. There are plenty around incl mine and even in my new book I have referred to others in a favourable light. Remember that whilst you may think you and I are the only ones reading your posts (this is a commonly held belief) in fact the site gets over 2 million hits a month so I and I am on a mission to improve folks' general understanding of what I believe to be an important DIY skill (for a bloke anyway) and from time to time I make these observations to 'jolt people'. The difference betw us - you understand - is that I write for all - and you write for yourself.



G

Oil vapor circuit 7 piece connector shattered (24 year old brittle plastic). Creating a new circuit. Pictures will be posted once installed.
Oil sump drain plug changed to hex bolt making it easier to take out. (damaged 12mm allen bolt previously installed).
Crowns cleaned up.
Outlet manifolds cleaned. Same size as gaskets so no modification needed. Kept as original size.
New big end shells.

Brit01 wrote:Oil vapor circuit 7 piece connector shattered (24 year old brittle plastic). Creating a new circuit. Pictures will be posted once installed.
New big end shells.

That part is not for oil vapor. It is the central "distributor" for engine vacuum. The carter ventilation is also hooked up to it, but it has much more function than just that.

I tend to disagree a little Whizzman sorry.
rethinking about it from a different angle yes this circuit has a role in crankcase pressure also.
I'm considering whether to take off the air intake tubes(trumpet inlets - not inlet manfiolds) and add a filter or oil catcher to reduce the hot oil vapor entering the carbs.

The main oil vapor pipe comes out of a connection on the oil fill pipe. This leads to 4 inlets on each carb.

1 small one on the inlet manifold that draws when idling and the carbs are closed, and the other attached to the trumpet which sucks the vapor through the carb when you open the throttle.

Sorry I made this diagram with names in Spanish for a friend here but it gives you an idea of the Alfa circuit.

This is the mod I'm thinking of making.

The small pipes on the inlet manifolds will have clean filtered air from the airbox flowing into them.
The inlets on the trumpets blocked off so carbs will keep clean and no contamination of the fuel will occur.

On the oil filler pipe, I have a catch tank and also a filter directed vertically to release crankcase pressure.

Just a small DIY oil catch container but I can check on it regularly to see how much it collects (honestly I have no idea how much will collect for now).
Other end will have a pipe attached leading to a filter.
I noticed on my brother in laws alfasud there is just a pipe pointing down to the ground and see lots of oil splatters on the front drive axle and rubber gaiters! No filter or anything just an escape pipe spitting it out to the ground. (we don't have emission tests here).