My Alfa Romeo 33 rebuild - FIRST TIMER

[Brit01]

They are hydraulic unfortunately.

Wish I had the mechanical tappets with the cam box lid easily accessible.

I will check the torque again of the exhaust manifold to eliminate easy possibilities. Ticking can come from here, but I doubt it can cause such a loud noise. Also wouldn't I feel and hear exhaust releases coming from below the car? This would be quite evident.

Regards,

Chris

[Guy Croft]

Might be good news.

I don't know if this reassures you any but hydraulic tappets are always VERY noisy until they fully charge-up with oil. This can take some time.

This is most alarming but if you carry on driving you may find the noise goes away.


G

[Brit01]

I really pray nothing serious has happened again Guy.

They did rattle on start up during the break in but then were quiet.

But after the 30 km ride home last night, I stopped in the garage, opened the bonnet and the right bank near the filter was ticking loudly when hot.
I did an oil change that morning.

Maybe when I start her again I'll run through the motion of charging them up. I heard revving up to 3000 rpm over 30 seconds and then idling.. repeating this.

Does the tappet near the oil filter tend to have less oil pressure than the others? Not sure how familiar you are with the Alfa boxer 8v.

Well my other 33 friend is coming over this weekend to compare his 'ticking' noise!
He's saving up money for a rebuild.

[Guy Croft]

Never worked on that engine, no.

Sorry but other than stripping the head on the affected side I have no other suggestions. You could re-use the head gasket I guess.

G

[Brit01]

I also have a spare tappet. If all fails I will place the spare tappet in.

Also a colleague is in USA right now. He'll be back in 18 days. Enough time to order new sets of gaskets from RockAuto.

Other than that maybe it is a small end bearing, when it gets very hot just enough clearance to tick/knock.

mmmmmm

Many thanks Guy.

I'll run it just a bit more and if I see no improvement I will remove the head to inspect the tappet.
I can't see any other way.

[Guy Croft]

Why do you suspect a small-end bush? Were the piston pins so loose you could rock them around in the rod?

G

[Brit01]

No rocking no, but just thinking about the heat expansion. Not sure how much of a clearance would be needed to start a knocking noise. That would be in my manual.

I guess they would also make a knocking sound rather than ticking.

My friend here suspects he has a small end knocking on his 33 so we plan to compare noises at the weekend.

If I remove the heads I may just well have new small ends put in to be on the safe side if I can get hold of them here.
I imagine they would have to manufacture them and install them to the correct clearance with the pins.

[Guy Croft]

I reamed the bushes on my 124 CSA too wide once and it rattled a fair bit but not under load, only on the over-run (lifting off the throttle). They never broke though and never got worse.

If you find the cam and tappet is the issue you better pause and consider the source of supply before changing them, I myself would trust few sources other than OE, there are some pretty poor quality cams and tappets available these days. My money would be on the cam lobe if indeed that is where the problem lies, poor quality blank, not hardened by chill-cast method. That kind of thing used to be quite common here in the 90s.

If you pull the head, check for any sign of piston-valve contact - though as I said that can only happen if you've machined the head radically (in which case you usually can't time her up without adjustable cam pulleys). However it can certainly happen if you get the cam timing wrong.

G

[Brit01]

Cams are OE from the Alfa romeo supplier in Argentina.
Tappets are INA.

I don't expect the cams here.

Possibly the tappets. But I had OE tappets in the engine previously installed before I purchased the car. Didn't last so I chose the well known German brand INA which are used in Bora/Golf/Passats/Beetles/Skoda etc.

Do you know BGA tappets? These can also be used for the Alfa boxer.

My heads haven't been touched.

Will give me piece of mind to remove the heads. My colleague has responded and will be able to bring back new gaskets from Dallas. BGA gaskets from Rockauto.

Chris

[Guy Croft]

Nothing wrong with INA, BGA I would not use.

Cam - OE, good. Unless for some unexplained reason the cam has gone dry during bedding in I cannot think of probable cause. It would be a shame to pull the head and find, well, nothing..

An good old tip I never tried but from an old garage hand from years back. Drain off a bit of regular engine oil and add a pint of EP90 gear oil to the engine in lieu and run her up hot and see what happens. EP 90 will not damage your motor. If the noise is coming from a lubricated part (cam/rod etc) it will go quieter.

If it's a mechanical contact it will stay noisy.

G

[Brit01]

Nothing wrong with INA, BGA I would not use.

Good to know. Almost bought a set of BGA tappets from UK.

An good old tip I never tried but from an old garage hand from years back. Drain off a bit of regular engine oil and add a pint of EP90 gear oil

Great thanks. I will try some 80w/90 gear oil. I need to replace my gearbox oil anyway.
So drain a pint and add a pint of this stuff to my engine.

If it's a damaged tappet/lobe it will go quiet then due to the higher viscosity.

Sorry for my ignorance what would be the mechanical parts that would stay noisy?

I assume after the test I would need to do a complete oil change (if I don't need to remove the head of course).

Also read a tip on an Alfa forum to check if a shell, small or big, is loose/worn. Pull the spark plug on the ticking side and if the noise disappears then it could well be one of the rod bearings.


Regards

Chris

[Urbancamo]

If there's a slightest possibility to capture some video about the noise, it would be lot easier to guess what's really wrong?

I have noticed in the past years that different noises are heard differently among people.

I think it's some kind of valvetrain noise. My parents own an old Mazda 626 and it has worn and maybe glogged hydraulic lifters and i have to say, the noise was sometimes terrible with hot oils! Wawe-like ticking that kept going and going...
Novadays it has no lifter noise anymore, found and oil that keeps old lifters quiet.

Pulling the plugs while idling is really great way to found if conrod bearings are bad. But i don't think it is your problem really..

And i really know what is it when your freshly builded engine starts to make unpleasant noises...

[Brit01]

Novadays it has no lifter noise anymore, found and oil that keeps old lifters quiet.

What oil did they use? A thicker oil? They do sell 60 viscosity here if that's what is needed in the end.
95% sure it's a lifter noise as the old lifter was totally destroyed and made the same horrible noise.

Once I get it hot again I will get the camera out.

Pulling the plugs while idling is really great way to found if conrod bearings are bad. But i don't think it is your problem really..

Great good to know and always best IMHO to rule out all possibilities.
Thanks.

And i really know what is it when your freshly builded engine starts to make unpleasant noises...

Was heartbreaking after all the late nights/cuts/bruises/ nights away from my wife and baby!

But I'm persistent and a perfectionist and will not give in to taking it to a mechanic who I don't know.

A mechanic here will never have taken so much time in cleaning all the parts/measuring, polishing, breaking in procedures etc etc.

I know you do but you are one of a kind. A GC does not exist here in Uruguay.

Can I drive the engine with the gear oil in? or just run it stationary until it warms up fully? Then empty it.

Just to add they do sell Liqui Moly 10w/60 racing oil here if you think my tappets are bleeding down too much when the engine gets hot and causing the ticking.
Currently using Valvoline 20w/50.
Have 5 litres of Motul 15w/50 ready to put in for it's regular oil but if we think a 10w/60 oil will help when the engine gets hot then this is available here. Many Alfa boxer owners have had success with similar race spec oils 10w/60.


Also just listened to a video with a leaking exhaust manifold and it was making a ticking noise - more muffled but very similar. Another thing to check.

[Guy Croft]

Keep it simple;

Put a pint of gear oil in the engine (obviously the rest to dipstick level will be whatever engine oil is already in there). this oil or that oil (of the types you mentioned) will not have any effect on hydraulic tappet behaviour.

Run up the engine or drive the car with the gear oil added to get it hot when the noise normally appears and see if there is any difference.

The tip about the plug lead is a good one, assuming it is actually making the noise at the time (eg: when hot and revved up), not much use if it only does it under load..



G

[WhizzMan]

If you are certain it's not a leaky exhaust, tappets are the most likely cause on this engine indeed.

Even INA can have a manufacturing defect every once in a while, but are you certain all oil channels to the tappets are cleaned out? Could it be that some debris found it's way into a channel or the tappet itself?

Yes, a slightly bent valve will cause the valve to either not close completely. However, a compression/leak down test would reveal that. Since you had good compression after building the engine, it must have occurred after you put it back together. That makes it very unlikely to be the cause.

I've had noisy tappets disappear "by themselves" after flushing a dirty engine (run once until up to temperature, make sure to drive and rev properly so oil gets all through the engine) with 1/5th of the engine oil replaced by ATF and subsequently putting new oil and oil filter on. Mind you, those were dirty engines, yours is fresh and clean. Even tho dirt can accumulate in the most inconvenient places, there is a good chance it will flush itself out and lodge itself in your oil filter as well. Don't be surprised if all of a sudden the engine becomes quiet again and a refresh of oil doesn't reveal any dirt.

Flushing a dirty engine always poses a risk of dislodging debris that will block an oil passage somewhere else. Keep a close eye on oil pressure, temperature and listen for new noises. If it's a racing engine, just don't flush it but pull it apart. If it's that dirty, it needs more than a flush for certain. This is for street cars that get driven short runs, never get up to temperature and never get serviced on time.

Guy says you can re-use the gasket if you want to do an inspection. I personally am not so certain (because of the thermosetting polymer) and with the availability and price of the part over here in the Netherlands, I wouldn't chance it. However, your situation is different, and the worst that can happen if you try, is that the gasket won't seal properly and you'll have to put a new one in after all.

I've cleaned out tappets in the past by slamming them on an old newspaper, on a table top, with the valve-end down. That way, the innards will come out and you can clean them and put them back together again. Be sure to work clean, use fresh engine oil to assemble them and when in doubt about the condition of the parts inside, toss them. Economically it doesn't make sense to do this, but if you really need the tappet and you don't have time to get new ones (11 pm on a Saturday, race on Sunday morning 9am!), this can work.