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Discussion Starter #1
OK guys - my 1982-era Green Cloverleaf engine has 1400 miles on the clock and was installed in the Green Machine last year. The engine was still crated from AR when I bought it, although for some reason in the intervening 20 years one of the inlet valves developed a crack and was replaced with parts raided from my 1978 Ti engine.

I don't want to ruin what is essentially a brand-new engine, so I would like to know what the best plan for routine servicing should be, such as...

1 - what oil to use? My Haynes manual says 10/50 or 10/40 mineral oil and I have been using 10/40 to date. I have heard a lot of talk about synthetic oils - are they really better for a 'Sud engine?

2 - cambelt replacement? I put new cambelts in last year, but I need to replace the camshaft oilseal on the LH bank anyway. Should the belts be changed every 12 months? I'm only asking because the procedure for replacement in Green Machine is even more entertaining than a normal 'Sud, involving mirrors and lots of cursing...:)

3 - still haven't got to the bottom of my carburation problem yet (been off sick for a couple of weeks), but how well do twin 36 IDF's stay in tune? Should I be investing in a synchronometer?

4 - my transaxle is easily the weakest link in the whole drivetrain. It is a 1978 Ti unit and 1st and 2nd synchromesh is very poor. I am nursing it by blipping the throttle on essential downchanges. I changed the oil completely about 500 miles ago. How long can I expect the 'box to last? Should I be thinking about getting a re-build/replacement?

5 - I still have the intended engine for Green Machine in pieces in the garage - it's a racing unit (never been assembled) from Warrior Racing and is allegedly a 1600cc (1.7 crank in a 1500 block) with Cosworth pistons, gas-flowed heads and stainless valves. I have seen a local company called A H Motorsports who deal in racing Boxer engines - does anyone know if these guys could build up my Warrior engine for fast road use?

Lots of questions I know, but I am looking to clock some more serious mileage this year and I don't want any mishaps in the engine department!

Thanks for your help,

Lauren
 

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all i know is dont use synthetic it is too thin for older engines, use either selenia or magnatec or some other good quality 10/40 or 15/40

nice find btw an engine with 1400 miles on it.
 

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oh and ah motorsport are very very good, they can do anything with your engine if you`ve got the bucks.
 

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(1)
I am no oil expert but I did experiment with an oil pressure gauge in my 1.7 Boxer and tried MotorWay10W40 semi, then 5W40 fully synthetic.

The pressure was good but obviously lower with the fully synthetic when cold (Around 40 PSI at idle) where the semi was 50 or more.

When hot and sitting in traffic the semi synthetic dropped to around 10 PSI at idle where the fully synthetic was around 12.

So from my findings fully synthetic was all round better in the viscosity stakes, runnier when cold, retaining viscosity when hot.

I think the '40' bit is the viscosity at 100C so mine must have been a little hotter than that- the boxer usually has no oil cooler.

(2) I have changed a camshaft oil seal with the engine in situ and without removing the cam cover.
I drilled through the metal shell of the oil seal, then used a screw to pull the old seal out.

(5) 1.7 crank in a 1.5 block making 1.6. This is correct.
I have used a 1.7 crank to replace one from a 1.6 8v Boxer and all was fine.

One last thing is that I have a 1.7 16v engine in my shed believed to be in good working order, but no Alfa to put it in. This chucks out about 129 BHP in the 145 and more in a pre-cat car- maybe 133 BHP?
 

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Discussion Starter #6
Thanks for your replies. Seeing as this engine is an un-modified stock unit I will probably stick with a quality mineral oil rather than experiment with synthetics - but I've got an idea of what viscosity I should consider for the Warrior engine when it finally goes in.

Stedee - the engine was zero miles when I got it; it was still in its original crate from Alfa Romeo. When the head came off to replace the cracked inlet valve it was confirmed that the engine had not been run since assembly. That's what made the cracked valve so strange...

Thanks Bodger for your additional comments; I am intrigued as to how you managed to remove your camshaft oil-seal without losing the cam timing; as far as I can see, I need to remove the plastic cambelt covers, cambelts and camshaft pulley, and then probably also the metal cambelt shroud before I can get at the oil-seal. That would lose cam timing for sure, or am I missing something???

Thanks for confirming that my Warrior engine is probably a stroker unit - and thanks for the offer of the 16v, which would be nice, but unfortunately the 16v heads are too tall to fit in my spaceframe chassis (standard 8v only just fits with acceptable cam-cover access). So its 8v for the Green Machine, but that doesn't mean I can't use big valves and a stroker crank... some fast road cams will probably squeeze a reliable 150 bhp which should work well enough!

Lauren
 

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If it is a brand new fresh engine then you don't want to use synthetic oil at the beginning anyway because it prevents the slight wear required to bed the piston rings to the cylinders.

If AHM are local to you then they would be ideal for you.
 

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Thanks for your replies. Seeing as this engine is an un-modified stock unit I will probably stick with a quality mineral oil rather than experiment with synthetics - but I've got an idea of what viscosity I should consider for the Warrior engine when it finally goes in.
I apreciate what you are saying but there are hundreds of thousands of Boxers running round on Semi Synthetic. Running in on mineral oil sounds good but the more synthetic it is the better IMHO. It would be interesting to cross-check things like main bearing clearances. I think I did this a while ago and there was no difference between the pre-and post synthetic clearances. A fair few boxers turn up on eBay with 125+ k miles on them and that must be down to better oil.

Thanks Bodger for your additional comments; I am intrigued as to how you managed to remove your camshaft oil-seal without losing the cam timing; as far as I can see, I need to remove the plastic cambelt covers, cambelts and camshaft pulley, and then probably also the metal cambelt shroud before I can get at the oil-seal. That would lose cam timing for sure, or am I missing something???
You definitely lose the timing. The covers, then the cam wheels need to come off. The cams are keyed so you can only put the cam wheels back in the correct position although I permanent markered Left and Right on my cam wheels to avoid mixing them up. Re-timing an 8v Boxer is child's play. Marks on the cam wheels line up with plugged holes in the top of the cam covers. TDC for the crank is found by removing the white plastic plug from the top of the bell housing and looking for the 'T' on the flywheel.

Thanks for confirming that my Warrior engine is probably a stroker unit - and thanks for the offer of the 16v, which would be nice, but unfortunately the 16v heads are too tall to fit in my spaceframe chassis (standard 8v only just fits with acceptable cam-cover access). So its 8v for the Green Machine, but that doesn't mean I can't use big valves and a stroker crank... some fast road cams will probably squeeze a reliable 150 bhp which should work well enough!

Lauren
Lots of people prefer the 8v anyway from what I understand and it can kick out as much power in a suitable state of tune.
 

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Discussion Starter #9
OK, this is good; so with 1400 miles on the engine I have effectively "run-in" with mineral oil, and for maximum longevity I can now switch to semi or full synthetic, of 15W50 viscosity or thereabouts? I'll do the oil and filter change when I replace the camshaft oil-seal and cam-belts.

Hopefully AHM can put the Warrior engine together and get some useful power from it; allegedly it is the spare engine kit for a Chris Knott Alfa Challenge championship winning team. It certainly has all the right bits - lightened flywheel, gas-flowed heads, new crank, pistons and valves and a pair of 44IDF-sized inlet manifolds. Should be good in the Green Machine, which is as light as the earliest 'Suds, but with 50% less frontal area :)

Thanks for your help!

Lauren
 

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I don't know if a 15W50 sounds like a mineral oil. I presume 10 and 5 W 50s are around with increased synthetic mix.
One suggestion to get your oil right is if you have an oil pressure gauge you need to see 1 bar or more at idle on a hot day. If a something W 40 doesn't do this, go thicker (xW50 etc).

Also on the gauge you'll see the point where it goes no further. This was about 60 PSI on my boxer. If you use thick oil, you should check that it doesn't hit this limit when you're cruising etc. or you will effectively be letting some of your oil flow through the pressure relief valve and not the crank. With a thinner oil you will get more flow.
I remember somebody at college had a Nova- it was a stunner but I haven't seen another for years.
 

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I don't know if a 15W50 sounds like a mineral oil.
15W50 Full Synthetic available from:
Motul (300V Competition)
Redline
Mobil 1 (Mobil1 Motorsport)

To name just three that are off the top of my head.

Amsoil make a 20W50, Redline also make a 20W50. Motul also make a 20W60.

Like I said earlier, not all synthetic oils are thin.
The ultra thin oils are nothing to do with protecting the engine either, it is all about very low emissions from startup. So not the way to go.
 

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You're getting onto a subject I wondered about. Is it better to have an oil that is thick enough not to drain back through the system when the engine's off, or one that's thin enough to move through the system quickly on startup?

I read somewhere that if you are gentle with the engine for the first minute or so it doesn't really matter whether you have a 5Wx or a 20Wx, so I have just chosen oil based on the second half of the number and ignored the first half.

I'm not an oil expert though and haven't tried the tastier oils mentioned above, just budget stuff.
 

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Discussion Starter #13
Thanks guys - with the current cold weather I am seeing up to 70 psi on the oil pressure gauge, but in the best Boxer tradition I am keeping the revs down until the cylinder head temperature exceeds 30°C. Pressure never drops below 18 psi when hot. It's nice to know there are synthetic oils out there that match the viscosity of mineral oil; I was worried that I would have to use 0W30 or something and have a smokey exhaust and then everyone would point at me and say "your valve guides have gone"...

Nova's seem to be getting very sparse these days - only about 1000 in the UK, of which maybe 50 actually on the road... and even fewer using the Alfa Boxer... and only Green Machine using Boxer engine, transmission and brakes!

Lauren
 
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