Castrol TWS 10W60?

[Brit33]

Hi guys,

Just joined the forum. Always been reading around the subject of oils and get into debates on other forums.

I have an alfa romeo 33 1.7 carby. 1988 Series 2.
Factory recommendation is 10w50.

Currently rebuilt the engine myself. Original crankshaft just polished, not reground as it was just within specs.
It has new flat tappets, cams, oil pump gears, etc etc.

Alfas are infamous for having low idle pressure.

This summer was a scorcher and was using Motul 300v 20w/60.
Temps in the sun stuck in traffic reached 55 c easily. 40 in the shade.
The 60 viscosity oil worked just great.

But now winter is upon us (5-10 c most days).
I have in stock Motul 300v 15w/50 AND Castrol TWS 10w60.

The Castrol would definately be good for summer as I couldn't find any more motul 20w/60.
Does the castrol have higher zinc levels than the motul?

Also I'm thinking of using the 300v 15w/50 for winter.
Ideally I would like to stay with the same brand of oil and not keep changing.

So really my question is if the Castrol 10w60 would be ok for winter here instead of the 15w/50 motul(which gets too thin in summer).

I know TWS Castrol is recommended by BMW now. What kind of lifters/tappets do they have? Flat ones like in the alfa?
I have INA flat lifters installed.

Regards,

Chris

 

[Bandito440]

I think you'd be fine with either. It doesn't seem to get very cold where you are. If you want maximum protection and cold start performance, how about Mobil 1 Racing 0w-50? It's loaded with zinc.

 

[Brit33]

Thanks Bandito440.

I doubt very much that I'd be able to get hold of that oil here. There are some common Mobil grades around but I've never seen 0w/50.

Also going below the winter rating concerns me a little on start up. Is there a 10w50 mobil 1 grade with the same high zinc level?

It's a shame I can't get Castrol 10w50 and use the 10w60 for summer. Sticking to the same brand is important as not to mix the additive packages of the 2 different makes each time.

Also the Mobil racing specs sheets state;
"Mobil 1 Racing 0W-30 and 0W-50 were developed specifically for racing engines and are not recommended for street use"

Does it have very small amount of additives such as detergent, anti-foam, etc etc.?

 

[Bandito440]

Here's the 0w-30 racing. It seems very stout.

M1 0w-30 VOA

I don't think there's a 10-50. There is a M1 15-50 that's sold here. It has a strong additive package and I use it in my motorcycle. Can you order Red Line oils? They make a 5w-50 that's very stout.

 

[Brit33]

Red line no.

Do Castrol sell a lighter oil for winter?

Maybe a 10w/50 or 15w/50. Edge range for example. I could only dine 5w/40 and 10w/60!!

I really do want to stay with one brand. But also have a 60 oil for the summer.

 

[Bandito440]

I think there's a Castrol Edge 5w-50 that's sold here in the US, but I've never used it. Perhaps a Castrol user will speak up...

 

[Brit33]

5w-50 Castrol would be great for winter.

quick warm up for my wife and fast lubrication but also keeping the 50 for the heavy town driving with lots of starts and stops.

I've contacted Castrol Uruguay to see if they import this one.

 

[Lead Shoes]

I have used some 5w50 Castrol I got on sale in my d16 civic, not much I can say about it technically, but it seemed to work well in my civic.

 

[jaj]

Just go with the Castrol TWS 10w-60. It shears to a 10w-50 viscosity within the first 1000 KM in BMW engines, so your Alfa will probably see the same evolution. It's one of the few over the counter oils that has comparable film strength to Motul 300V. I've used it in my BMW's for ten years and they've started and run fine with it in zero Celsius or colder weather.

 

[Brit33]

5w-50 certainly does sound appealing reading their web page but of course a 24 year old boxer engine with double Dellorto carbs is quite a different beast compared with modern engines such as ones from a civic.

If I can get hold of it certainly worth a try in winter here.

 

[CATERHAM]

Originally Posted By: Brit33

Alfas are infamous for having low idle pressure.

This summer was a scorcher and was using Motul 300v 20w/60.
Temps in the sun stuck in traffic reached 55 c easily. 40 in the shade.
The 60 viscosity oil worked just great.

But now winter is upon us (5-10 c most days).
I have in stock Motul 300v 15w/50 AND Castrol TWS 10w60.

The Castrol would definately be good for summer as I couldn't find any more motul 20w/60.
Does the castrol have higher zinc levels than the motul?

Also I'm thinking of using the 300v 15w/50 for winter.
Ideally I would like to stay with the same brand of oil and not keep changing.

So really my question is if the Castrol 10w60 would be ok for winter here instead of the 15w/50 motul(which gets too thin in summer).

I know TWS Castrol is recommended by BMW now. What kind of lifters/tappets do they have? Flat ones like in the alfa?
I have INA flat lifters installed.

Hi Chris,

First the grade on the bottle is not the viscosity of the oil but represents a range of kinematic viscosities.
Oil pressure corresponds directly with the HTHSV rating of the oil regardless of the oil grade.
The 20W-60 300V you liked is a VERY heavy oil with a HTHSV of 7.17cP and 162 VI. Everything else you've mentioned will be much lighter; i.e., lower oil pressure.

The Motul 300V 15W-50 (HTHSV 5.33cP, VI 154) and TWS 10W-60 (HTRHSV 5.3cP, VI 168) have similar viscosity spec's but the Motul should be some what heavier than the TWS due to it's lower VI and the fact it won't shear as much as the TWS is known to.

Most 5W-50's like Castrol are GP III based and are lighter still with a HTHSV in the 4.3cP to 4.6cP range. Again this will be reflected in even lower oil pressure. They will be better for starting in the winter and may work assuming your oil temp's don't get too high.

Good Luck!

 

[Brit33]

Very interesting Caterham. An angle that I've never looked at oil before.

So the 10w/60 TWS with a HTRHSV 5.3 cP would actually be lighter for winter than the 15w/50 Motul?

Why is the Motul with a VI of 154 heavier than the Castrol with a VI of 168.
Appears also the castrol will retain it's thickness better than the motil 60 oil at working temp.

trying to understand the relation between the absolute viscosity and VI, viscosity index.

So the lower the VI, the more the drop in viscosity as the oil warms up. The higher the VI value, the less the drop in viscosity as the oil warms up.

A little confusing but something that interests me more.

Something to add remember the boxer engine is a high revving engine.

 

[CATERHAM]

It shouldn't come as a complete surprise that the 10W has a higher VI than the 15W.
Since these two oils have much the same HTHSVs with the Motul having a somewhat lower VI it will be heavier at all temp's below 150C. It should be slightly noticeably even at normal operating temp's, maybe 2-3 psi lower oil pressure but most noticeable on a cold start-up.

But since the TWS tend's to shear (loss viscosity) quite a bit in service that should be the most noticeable difference between the two oils.

BTW I didn't know Alfa ever made a boxer engine, just L4 and V6s?

 

[Brit33]

ah now you are referring to the winter rating with the VI. Now I understand. Yes that's clear.

So what would you recommend for the winter here? (av.8-10 c).
10w would be better but it's a 10w/60 but as you said similar HTHSV ratings. Much less HTHSV than the motul 20w/60 I see.
I think the Castrol may be a good choice as it's the thinnest 60 oil on the scale.

I change oil every 6 months and never really exceed 4000 kms in this time frame.

Just reading more of your threads and saw this great explanation also.

oh yes all the alfsuds, 33 models and sprints are 4 cylinder boxers in Europe. Very popular indeed and wonderful engines to drive and listen to. from early 70's - 94.

"Since the HTHS vis spec' correlates so well with the operating viscosity in an engine at typical operating temps and the KV100 spec' doesn't, the following guide might be useful to judge how thick or thin an oil actually will be in an engine:

HTHS Vis' Value

2.60 cP ...........a light 20wt oil
2.70 cP ...........a mid-grade 20wt oil
2.80 cP ...........a heavy (thick) 20wt oil
2.91 - 3.10 cP ... a light 30wt oil
3.20 - 3.40 cP ... a mid-grade 30wt oil
3.50 - 3.60 cP ... a heavy 30wt oil
3.70 - 3.80 cP ... a light 40wt oil
3.90 - 4.10 cP ... a mid-grade 40wt oil
4.11 - 4.20 cP ... a heavy 40wt oil
4.21 - 4.40 cP ... a light 50wt oil
4.50 - 4.70 cP ... a mid-grade 50wt oil
4.80 - 5.20 cP ... a heavy 50wt oil
5.3 .........cP entry point to a 60wt oil

For any given HTHS vis' you will have a range of possible KV100 values but it is the HTHS vis' that correlates with operating viscosity."

 

[Hessam]

dont know if you have access to liqui-moly products in urugay, but here are a couple suggestions from their line, which would work perfect in your alfa engine during hot summer months:

http://www.liqui-moly.de/liquimoly/produktdb.nsf/id/us_2035.html?OpenDocument&land=US

http://www.liqui-moly.de/liquimoly/produktdb.nsf/id/us_2024.html?OpenDocument&land=US

it also says on their site, that there's a dedicated uruguay site, so there should be some retailers in your country.


http://www.liquimoly.com.uy/

 

[Brit33]

Hessam, yes we do have these Liqui Moly oils here.
Did consider them but the cost put me off. The 10w60 was shocking. (150 USD for the 5 litres)

Why would would it offer benefits over the Castrol or Motul?

Thanks

 

[CATERHAM]

Brit33, so your winters certainly aren't very cold.
Obviously you don't want to run an oil any heavier than necessary, just enough to maintain the minimum required OP.
I'd probabily try the cheapest readily available 5W-50.

BTW, do you have an oil temperature gauge installed?
If the problem is high oil temp's, installing an oil cooler may be a solution?

 

[Brit33]

Originally Posted By: CATERHAM
Brit33, so your winters certainly aren't very cold.
Obviously you don't want to run an oil any heavier than necessary, just enough to maintain the minimum required OP.
I'd probabily try the cheapest readily available 5W-50.

BTW, do you have an oil temperature gauge installed?
If the problem is high oil temp's, installing an oil cooler may be a solution?


Temp can fall below freezing but yes never too cold. But I have noticed the 20w being harder to start as the winter has set in.

Funny you should mention that as I just got myself a VDO gauge and sensor to measure the oil temp.
Just got to find the time to fit it.
Got an issue with the idle progression I need to fix this weekend.

5w-50 oils don't seem to be available here, even if it was it would be pricey.. So it's a 15w/50, 10/60 or 20w/60. I've heard many good results from the 10w/60 from boxer owners in Europe.

I'm inclined to try the Castrol 10W/60.

 

[Brit33]

Caterham:

I found this that the Castrol RS 10w/60
only has a HTHS 3.7 !

So the TWS is a different beast?
Can you confirm the HTHS number for TWS?

Thanks

 

[CATERHAM]

Since you already have the Castrol 10W-60 why not; it will be a major improvement over the 20W-60 300V on start-up.
BTW the Castrol 10W-60 is a long drain oil and a 4,000 kms OCI would be a waste of this expensive oil. You could go 3 times that long without issue or two years. I'd at least run it into the heat of next summer to see how it holds up.
By then you'll have your new oil temp' gauge installed and you'll know if your low oil pressure problem is related to high oil temp's or simply loose bearings and/or a low capacity oil pump.